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1
Lyon, Bruce E., and Daizaburo Shizuka. "Extreme offspring ornamentation in American coots is favored by selection within families, not benefits to conspecific brood parasites." Proceedings of the National Academy of Sciences 117, no. 4 (2019): 2056–64. http://dx.doi.org/10.1073/pnas.1913615117.
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Offspring ornamentation typically occurs in taxa with parental care, suggesting that selection arising from social interactions between parents and offspring may underlie signal evolution. American coot babies are among the most ornamented offspring found in nature, sporting vividly orange-red natal plumage, a bright red beak, and other red parts around the face and pate. Previous plumage manipulation experiments showed that ornamented plumage is favored by strong parental choice for chicks with more extreme ornamentation but left unresolved the question as to why parents show the preference. Here we explore natural patterns of variation in coot chick plumage color, both within and between families, to understand the context of parental preference and to determine whose fitness interests are served by the ornamentation. Conspecific brood parasitism is common in coots and brood parasitic chicks could manipulate hosts by tapping into parental choice for ornamented chicks. However, counter to expectation, parasitic chicks were duller (less red) than nonparasitic chicks. This pattern is explained by color variation within families: Chick coloration increases with position in the egg-laying order, but parasitic eggs are usually the first eggs a female lays. Maternal effects influence chick coloration, but coot females do not use this mechanism to benefit the chicks they lay as parasites. However, within families, chick coloration predicts whether chicks become “favorites” when parents begin control over food distribution, implicating a role for the chick ornamentation in the parental life-history strategy, perhaps as a reliable signal of a chick’s size or age.
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Porter, Elaine, David Anderson, and Elise Ferree. "Non-breeding Nazca Boobies (Sula Granti) Show Social and Sexual Interest in Chicks: Behavioural and Ecological Aspects." Behaviour 141, no. 8 (2004): 959–77. http://dx.doi.org/10.1163/1568539042360134.
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AbstractAdult Nazca boobies (Sula granti) show an unusual interest in both conspecific and congeneric nestlings, visiting them at their nest sites and performing mixtures of affiliative, aggressive, and sexual behaviours. Using a 20 year database from a large Nazca booby colony on Isla Española, Galápagos Islands, Ecuador, we describe the behaviour and the individuals performing the behaviour. Non-parental Adult Visitors ('NAVs') are typically 'unemployed' (non-breeding birds or recently failed breeders), and make visits of 1-60 min to unguarded chicks. Males and females are equally likely to exhibit the behaviour, if they are unemployed; since most unemployed birds are male, due to a sex ratio bias, most NAVs are male. Very young chicks and chicks nearing fledging are not visited, because young chicks are always attended by protective parents, and old chicks can defend themselves. When acting affiliatively, NAVs may simply stand by the chick, or may preen it and present gifts of pebbles and feathers. Aggression by the NAV often leaves scratches on the chick's body, but seldom causes the chick's death directly. However, landbirds take blood-meals from the scratches during food shortages, deepening the wound and eventually killing the chick. The least common NAV behaviour is sexual, in which adults perform male copulatory behaviour with the chick. Sexual behaviour occurs in 14.3% of visits by males, and 6.8% of visits by females. NAV behaviour is the direct or indirect cause of mortality of up to 24.6% of chicks, representing up to 41.6% of all deaths, in a given year. Approximately 80% of non-breeding birds in a given year show NAV behaviour, and since most adults are non-breeders at some point in life, most adults show NAV behaviour at some point. We propose a number of hypotheses to explain the causation of this puzzling and ecologically important behaviour.
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Li, Zeying, Tiemin Zhang, Kaixuan Cuan, et al. "Sex Detection of Chicks Based on Audio Technology and Deep Learning Methods." Animals 12, no. 22 (2022): 3106. http://dx.doi.org/10.3390/ani12223106.
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The sex detection of chicks is an important work in poultry breeding. Separating chicks of different sexes early can effectively improve production efficiency and commercial benefits. In this paper, based on the difference in calls among one-day-old chicks of different sexes, a sex detection method based on chick calls is designed. Deep learning methods were used to classify the calls of chicks and detect their sex. This experiment studies three different varieties of chicks. The short-time zero-crossing rate was used to automatically detect the endpoints of chick calls in audio. Three kinds of audio features were compared: Spectrogram, Cepstrogram and MFCC+Logfbank. The features were used as the input in neural networks, and there were five kinds of neural networks: CNN, GRU, CRNN, TwoStream and ResNet-50. After the cross-comparison experiment of different varieties of chicks, audio features and neural networks, the ResNet-50 neural network trained with the MFCC+Logfbank audio features of three yellow chick calls had the highest test accuracy of 83% when testing Three-yellow chicks’ calls. The GRU neural network trained with the Spectrogram audio features of native chick calls had the highest test accuracy of 76.8% when testing Native chicks’ calls. The ResNet-50 neural network trained with Spectrogram audio features of flaxen-yellow chick calls had the highest test accuracy of 66.56%when testing flaxen-yellow chick calls. Multiple calls of each chick were detected, and the majority voting method was used to detect the sex of the chicks. The ResNet-50 neural network trained with the Spectrogram of three yellow chick calls had the highest sex detection accuracy of 95% when detecting the three yellow chicks’ sex. The GRU neural network trained with the Spectrogram and cepstrogram of native chick calls and the CRNN network trained with the Spectrogram of native chick calls had the highest sex detection accuracy of 90% when detecting the native chicks’ sex. The Twostream neural network trained with MFCC+Logfbank of flaxen-yellow chick calls and the ResNet-50 network trained with the Spectrogram of flaxen-yellow chick calls had the highest sex detection accuracy of 80% when detecting the flaxen-yellow chicks’ sex. The results of the cross-comparison experiment show that there is a large diversity between the sex differences in chick calls of different breeds. The method is more applicable to chick sex detection in three yellow chicks and less so in native chicks and flaxen-yellow chicks. Additionally, when detecting the sex of chicks of a similar breed to the training chicks, the method obtained better results, while detecting the sex of chicks of other breeds, the detection accuracy was significantly reduced. This paper provides further perspectives on the sex detection method of chicks based on their calls and help and guidance for future research.
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Hébert, Percy N., and Robert M. R. Barclay. "Asynchronous and synchronous hatching: effect on early growth and survivorship of Herring Gull, Larus argentatus, chicks." Canadian Journal of Zoology 64, no. 10 (1986): 2357–62. http://dx.doi.org/10.1139/z86-351.
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The adaptive significance of asynchronous hatching in the Herring Gull, Larus argentatus, was examined during the summer of 1984 at Kent Island, New Brunswick. Chick growth and behaviour in 28 experimental three-egg clutches in which the eggs hatched synchronously (i.e., hatch interval ≤ 24 h between the first (A chick) and last (C chick) hatched) were compared with that of 15 control three-egg nests with normal hatching asynchrony (A–C hatch interval > 24 h). All chicks had similar hatch weights, except for control C chicks, which on average were significantly lighter than their nest mates and experimental chicks. Growth rates were also similar for all chicks within and between groups, except for control C chicks, which grew at a significantly slower rate compared with nest mates and experimental chicks. In control broods, C chicks disappeared first significantly more often than A or B chicks. In experimental broods, a similar proportion of A, B, and C chicks disappeared first. Survivorship, through to day 5 posthatch, was significantly lower for control C chicks than for control A and B chicks as well as experimental chicks. These results suggest that the benefit Herring Gulls achieve hatching their eggs asynchronously results from the competitive advantage accrued to the A chick (and the B chick to some degree), which allows them to obtain more food, especially during periods of food stress. Subsequently the probability of survival of the older, more fit chick(s) is enhanced.
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Wood, Samantha M. W., Scott P. Johnson, and Justin N. Wood. "Automated Study Challenges the Existence of a Foundational Statistical-Learning Ability in Newborn Chicks." Psychological Science 30, no. 11 (2019): 1592–602. http://dx.doi.org/10.1177/0956797619868998.
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What mechanisms underlie learning in newborn brains? Recently, researchers reported that newborn chicks use unsupervised statistical learning to encode the transitional probabilities (TPs) of shapes in a sequence, suggesting that TP-based statistical learning can be present in newborn brains. Using a preregistered design, we attempted to reproduce this finding with an automated method that eliminated experimenter bias and allowed more than 250 times more data to be collected per chick. With precise measurements of each chick’s behavior, we were able to perform individual-level analyses and substantially reduce measurement error for the group-level analyses. We found no evidence that newborn chicks encode the TPs between sequentially presented shapes. None of the chicks showed evidence for this ability. Conversely, we obtained strong evidence that newborn chicks encode the shapes of individual objects, showing that this automated method can produce robust results. These findings challenge the claim that TP-based statistical learning is present in newborn brains.
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Collias, Nicholas. "FILIAL IMPRINTING AND LEADERSHIP AMONG CHICKS IN FAMILY INTEGRATION OF THE DOMESTIC FOWL." Behaviour 137, no. 2 (2000): 197–211. http://dx.doi.org/10.1163/156853900502024.
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AbstractExperiments are reported on filial imprinting and leadership among white leghorn chicks in relation to family integration. Chicks hatched in isolation were given their first exposure to certain parental stimuli (a moving person or clucking sounds recorded from a broody hen) at various ages after hatching from the first to 10th day. Logistic regression and multiple likelihood analysis of the results showed that a significant tendency to follow or to be attracted to parental stimuli was much the greatest during the first day after hatching and then declined exponentially during the rest of the first week. There was a significant correlation between visual and auditory responses to parental stimuli, as well as between a chick's positive responses to clucking and the giving of distress cries by the chick when clucking ceased. Some individual chicks showed a significant tendency to lead the other chicks of a group to stimuli representing the mother, such as a source of warmth, or to the maternal voice (recorded clucking from a speaker).
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Morris, Ralph D., Michelle Woulfe, and G. D. Wichert. "Hatching asynchrony, chick care, and adoption in the common tern: can disadvantaged chicks win?" Canadian Journal of Zoology 69, no. 3 (1991): 661–68. http://dx.doi.org/10.1139/z91-097.
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In 1987 and 1988, common tern (Sterna hirundo) chicks at a colony near Port Colborne, Ontario, were individually colour banded according to known hatch order. Intraclutch hatch intervals produced size disparities among chicks at brood completion; third-hatched chicks were significantly lighter and at a significant survival disadvantage compared with their earlier-hatched siblings. There were differences in feeding rates according to hatch order and many third-hatched chicks obtained fewer or no feedings during our periods of observation. Sixty-five chicks known to have abandoned their home broods gained acceptance into foreign broods. Chicks that remained in the foreign brood for more than 2 days (average residency 11.9 ± 5.3 days; n = 26) were fed and brooded by the foster parents, were on average older than the youngest resident chick, but were not always the last hatched in their home brood. Conversely, chicks that were in a foreign brood for less than 2 days were no different in age from the youngest resident chick. Survival and fledging success was highest for chicks accepted into two chick broods in which they were older than the resident second chick; in effect, the adoptee became the second chick. Parents that accepted a foreign chick for more than 2 days experienced a seasonal fitness loss compared with nonadopting parents. As the only viable option available to them, selection favours movement away from home broods by chicks that may be disadvantaged there.
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Petek, M., A. Orman, S. Dikmen, and F. Alpay. "Physical chick parameters and effects on growth performance in broiler." Archives Animal Breeding 53, no. 1 (2010): 108–15. http://dx.doi.org/10.5194/aab-53-108-2010.
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Abstract. This study was made to compare physical chick quality indicators such as chick length and feather colour and their effects on the uniformity and subsequent growth performance in broiler. For this reason; 600 day old male chicks were used. Chicks were classified into two groups on the basis of their feather colour: deep and light yellow. Then, chicks in each group were further divided into three groups as small, middle and large according to their body length. The length of the middle group animals was varied between 18.0–18.3 cm, while that of the largest group was greater than 18.3 cm and the small group was lesser than 18.0 cm. A positive correlation between chick length and chick weight was observed in all groups at the 0 day of age. Body length uniformity in day old chick was more important than body weight uniformity. Longer chicks exhibited better growth potential throughout the experiment. The feeding efficiency and survival rate of longer chicks were numerically greater compared to smaller chicks. There were no significant differences for subsequent growth parameters in feather colour groups. Consequently; length of day old chick can be used as important criteria for selection of higher quality chicks having better growth performance.
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Gębczyński, Andrzej, Jan R. E. Taylor, and Marek Konarzewski. "Growth of Dovekie (Alle alle) chicks under conditions of increased food demand at the nest: two field experiments." Canadian Journal of Zoology 74, no. 6 (1996): 1076–83. http://dx.doi.org/10.1139/z96-119.
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To test whether Dovekies, Alle alle (small arctic alcids laying single-egg clutches), can increase parental effort, we increased food demand in their nests in two experiments. First, we introduced a second chick to the nests. Second, we rotated a number of chicks among a smaller number of nests, producing equivalents of 2, 1.5, and 1 (control) chicks per nest. Fledging success in the nests with twins (0.63 chick per nest) was higher than in unmanipulated broods of 1 chick (0.46 chick per nest). Chicks that fledged successfully in the two experiments grew at significantly lower rates and fledged at lower body masses and later than did rotated control chicks and unmanipulated single chicks. The latter two groups did not differ one from another. Growth rates and body masses of the chicks from the 2/1 rotation group (equivalent to 2 chicks per nest) were too low to indicate any substantial increase in the rate of provisioning by adults (over the rate satisfying the maximum energy consumption of an unmanipulated single chick). We associate this with the adults' energetically expensive mode of foraging and high field metabolic rates. However, the deferred fledging of rotated and twinned chicks might have considerably increased the total food demand in their nests (from hatching to fledging) that had to be met by the parents.
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Christensen, JW, and BL Nielsen. "Environmental enrichment for ostrich, Struthio camelus, chicks." Animal Welfare 13, no. 2 (2004): 119–24. http://dx.doi.org/10.1017/s0962728600026853.
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AbstractCommercially reared ostrich chicks are typically kept in barren, indoor environments. This experiment investigated the effects of environmental enrichment on the pecking behaviour, exploration, food consumption and novelty responses of ostrich chicks aged 10 to 21 days. Four groups of 20 randomly selected ostrich chicks were housed in heated huts at one day of age (Day 1), and at Day 10 were allowed access to sand-covered areas (30 m2) that were either barren (control: n = 2 groups) or enriched with cabbage, coniferous cones and sticks (enriched: n = 2 groups). Pecking behaviour was recorded by focal sampling the behaviour of five chicks per group for four 5 min periods per day on Day 10 and Day 13. All enriched chicks pecked at the cabbage, of which they consumed considerable amounts (26 ± 3 g/chick/day). The enriched chicks did not have higher overall pecking frequencies but tended to peck less at fixtures in the pen, compared to control chicks. Additionally, the enriched chicks showed increased exploration in terms of the percentage of chicks observed outside the heated huts. In a novel object test, enriched chicks stayed closer to and delivered more pecks at sorrel (Rumex acetosa) than did control chicks, whereas there was no difference between the treatment groups in their response to adult ostrich feathers. Enriched chicks consumed more food (79 ± 0.4 g/chick/day) than did control chicks (67 ± 09 g/chick/day) during the experimental period. We suggest that environmental enrichment improves the welfare of ostrich chicks in terms of increasing exploration and reducing pecking at fixtures in the pen, without compromising food consumption.
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Desrochers, Barbara A., and C. Davison Ankney. "Effect of brood size and age on the feeding behavior of adult and juvenile American Coots (Fulica americana)." Canadian Journal of Zoology 64, no. 7 (1986): 1400–1406. http://dx.doi.org/10.1139/z86-208.
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From 6 July to 12 August 1984 we studied the effects of chick age and brood size on the foraging behavior of American Coots (Fulica americana). Adults dove more frequently and fed a greater proportion of prey items, captured by diving and pecking, to their chicks when the chicks were young. Adults with large broods fed their young more frequently than did adults with small broods. The frequency of chick dives increased and pecking frequency decreased as the chicks matured. Diving efficiency was greatest in young chicks and in chicks from larger broods, but pecking efficiency was greatest in old chicks, with brood size having no effect. Chicks remained close to their parents, and to emergent vegetation, when they were young and foraged farther away as they grew older. These trends seem to result from increased self-feeding capabilities and decreased dependence on parents as the chicks matured; brood size did not affect most behaviors.
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Yeboah, P. P., L. A. Konadu, J. A. Hamidu, et al. "Comparative analysis of hatcheries contribution to poor development of day-old chicks based on biological and immunological performance." November-2019 12, no. 11 (2019): 1849–57. http://dx.doi.org/10.14202/vetworld.2019.1849-1857.
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Background and Aim: The quality of day-old chicks is a cornerstone to successful poultry production. Chicks with a poor quality start slowly in the field and may have high feed intake, poor growth rate, and poor feed conversion ratio. The current study aimed to assess chick quality challenges encountered from day-old chicks hatched in most commercial hatcheries in Ghana. Materials and Methods: A total of 300 day-old chicks each were obtained from commercial hatcheries in Ghana and Europe. The chicks were labeled as locally hatched broiler day-old chicks (LBDOC) and foreign hatched broiler day-old chicks (FBDOC), respectively. Chicks were reared and monitored from day old to 21 days post-hatch. Sample of chicks (n=25) from each hatchery was euthanized weekly at 1, 7, 14, and 21 days and blood samples collected for analysis. The parameters measured included physical, hematological, immunological, histological, and bacteriological characteristics. All data were analyzed by SAS Proc GLM at p<0.05. Results: The live weight of chicks was higher in FBDOC compared to LBDOC on the 1st day. The chick length and shank length of FBDOC were longer than the LBDOC. The 7-day chick mortality was 6% in LBDOC as compared to 1.5% in FBDOC. The LBDOC also had a higher wet and dry residual yolk sac percentages as well as higher residual yolk sac fluid volume than the FBDOC. The rate of yolk sac disappearance of the FBDOC was higher than the LBDOC. More than half of the LBDOC had developed navel strings and leaky navel compared to FBDOC. The LBDOC recorded Escherichia coli, Proteus, Streptococcus spp., and Gram-negative bacteria in the residual yolk sac isolated through the 21 days while FBDOC recorded E. coli, Proteus, and Gram-negative bacteria. The intestinal villi count, lengths, width, and surface area were all not significantly different. The blood monocyte levels appeared higher in FBDOC than LBDOC, which give evidence of higher immunity in FBDOC than LBDOC. Conclusion: The results indicate a challenging situation in maintaining the quality of locally hatched broiler day-old-chicks compared to foreign hatched broiler-day-old-chicks. The study demonstrates that chick quality impact goes beyond the physical characteristics of chick weight and chick length, and the higher performance of FBDOC may be influenced by compliance with international hatchery standards and vaccination protocols.
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Martijena, I. D., and A. Arce. "Transient benzodiazepine – GABAA receptor increase after a passive avoidance learning in synaptosomal membranes from chick forebrain." Canadian Journal of Physiology and Pharmacology 72, no. 3 (1994): 233–37. http://dx.doi.org/10.1139/y94-036.
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One-day-old chicks were exposed to a one-time passive avoidance learning task. After chicks peck a bead dipped in a bitter-tasting liquid, they learn to stop pecking the bead. Radioligand binding analysis of [3H]flunitrazepam was performed on crude synaptosomal membranes from forebrains, at 10, 30, and 60 min post-training. Water-trained chicks (control) pecked a bead dipped in water, and they did not learn to stop pecking the bead. The water control was complemented with a methyl anthranilate fed control chick to demonstrate that taste per se does not affect the [3H]flunitrazepam binding. At 30 min in relation to 10 min post-training, the Bmax increased 31% in water-trained chicks and 56% in taste-trained chicks, with Bmax of the taste-trained chicks reaching a value 22% higher than that in water-trained chicks. The difference, attributable to the learning, disappeared at 60 min post-training, and at all times the affinity remained unchanged. The Bmax increase in water-trained chicks might be attributable to psychological stress accompanying the task and the Bmax increase in taste-trained chicks attributable to the learning in addition to the stress accompanying the task. The results suggest that the receptor increase associated with learning is involved in early stages of memory formation.Key words: chick learning, stress, chick forebrain, flunitrazepam binding.
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Daisley, Jonathan Niall, Elena Mascalzoni, Orsola Rosa-Salva, Rosa Rugani, and Lucia Regolin. "Lateralization of social cognition in the domestic chicken ( Gallus gallus )." Philosophical Transactions of the Royal Society B: Biological Sciences 364, no. 1519 (2008): 965–81. http://dx.doi.org/10.1098/rstb.2008.0229.
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In this paper, we report on the ongoing work in our laboratories on the effect of lateralization produced by light exposure in the egg on social cognition in the domestic chick ( Gallus gallus ). The domestic chick possesses a lateralized visual system. This has effects on the chick's perception towards and interaction with its environment. This includes its ability to live successfully within a social group. We show that there is a tendency for right brain hemisphere dominance when performing social cognitive actions. As such, chicks show a left hemispatial bias for approaching a signalled target object, tend to perceive gaze and faces of human-like masks more effectively when using their left eye, are able to inhibit a pecking response more effectively when viewing a neighbour tasting a bitter substance with their left eye, and are better able to perform a transitive inference task when exposed to light in the egg and when forced to use their left eye only compared to dark-hatched or right eye chicks. Some of these effects were sex specific, with male chicks tending to show an increased effect of lateralization on their behaviours. These data are discussed in terms of overall social cognition in group living.
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Sola-Ojo, F. E., K. I. Ayorinde, A. A. Toye, et al. "Growth traits and performance of caged Fulani ecotype chickens fed commercial diets meant for broiler and pullet chicks." Nigerian Journal of Animal Production 41, no. 1 (2021): 68–76. http://dx.doi.org/10.51791/njap.v41i1.2692.
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Two Hundred and six day old Fulani Ecotype chicks (FEC)were used to investigate the effect of feeding two types of diet (Chick starter diet and Broiler starter diet formulated to meet standard nutritional requirement of pullets and broiler chicks) on growth traits and performance from O to 8 weeks. The broiler starter diet contained 23% Crude Protein (CP) and 3000Kcal/kg Metabolizable Energy (ME), and the Chick starter diet contained 21% CP and 2800Kcal/Kg ME. The growth traits measured were body weight (BW), body length (BL), body girth (BG), wing length (WL), thigh length (TL), drumstick length (DL), keel length (KL), and shank length (SL), while chicks performance were estimated from feed intake. feed efficiency, growth rate and weight gain. Average body weight of chicks fed broiler starter diet were significantly (P<0.05) higher from week 1 to 8. Chicks fed broiler starter diet exhibited numerically higher BL, BG, WL, TL, DL and KL than those fed chick starter diet at all ages and differences were significant (P<0.05) at some ages. Chicks fed broiler starter diet significantly (P<0.05) consumed more feed at week 1 and 2, and they gained more weight than those fed chick starter diet from 0 to 4 weeks (120.51 vs. 97.89g), and 5-8 weeks (255.11 vs. 239.13g). Feed efficiency in chicks fed broiler starter diet was relatively higher by 13.21% than observed in those fed chick starter diet from day old to 4 weeks and this translated to faster growth rate during the period in the former group (34.30% Vs.32.67%). This Study shows that the broiler starter diet produced superior growth traits and better feed efficiency in Fulani Ecotype chicks.
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Dilley, Ben J., Delia Davies, Alexander L. Bond, and Peter G. Ryan. "Effects of mouse predation on burrowing petrel chicks at Gough Island." Antarctic Science 27, no. 6 (2015): 543–53. http://dx.doi.org/10.1017/s0954102015000279.
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AbstractSince 2004 there has been mounting evidence of the severe impact of introduced house mice (Mus musculusL.) killing chicks of burrow-nesting petrels at Gough Island. We monitored seven species of burrow-nesting petrels in 2014 using a combination of infra-red video cameras augmented by burrowscope nest inspections. All seven camera-monitored Atlantic petrel (Pterodroma incertaSchlegel) chicks were killed by mice within hours of hatching (average 7.2±4.0 hours) with an 87% chick failure rate (n=83 hatchlings). Several grey petrel (Procellaria cinereaGmelin) chicks were found with mouse wounds and 60% of chicks failed (n=35 hatchlings). Video surveillance revealed one (of seven nests filmed) fatal attack on a great shearwater (Puffinus gravisO’Reilly) chick and two (of nine) on soft-plumaged petrel (Pterodroma mollisGould) chicks. Mice killed the chicks of the recently discovered summer-breeding MacGillivray’s prion (Pachyptila macgillivrayiMathews), with a chick mortality rate of 82% in 2013/14 and 100% in 2014/15. The closely-related broad-billed prion (P. vittataForster) breeds in late winter and also had a chick mortality rate of 100% in 2014. The results provide further evidence of the dire situation for seabirds nesting on Gough Island and the urgent need for mouse eradication.
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Inzani, Emma, Laura Kelley, Robert Thomas, and Neeltje J. Boogert. "Early-life diet does not affect preference for fish in herring gulls (Larus argentatus)." PeerJ 12 (July 11, 2024): e17565. http://dx.doi.org/10.7717/peerj.17565.
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Urban populations of herring gulls (Larus argentatus) are increasing and causing human-wildlife conflict by exploiting anthropogenic resources. Gulls that breed in urban areas rely on varying amounts of terrestrial anthropogenic foods (e.g., domestic refuse, agricultural and commercial waste) to feed themselves. However, with the onset of hatching, many parent gulls switch to sourcing more marine than anthropogenic or terrestrial foods to provision their chicks. Although anthropogenic foods may meet chick calorific requirements for growth and development, some such foods (e.g., bread) may have lower levels of protein and other key nutrients compared to marine foods. However, whether this parental switch in chick diet is driven by chicks’ preference for marine foods, or whether chicks’ food preferences are shaped by the food types provisioned by their parents, remains untested. This study tests whether chick food preferences can be influenced by their provisioned diet by experimentally manipulating the ratio of time for which anthropogenic and marine foods were available (80:20 and vice versa) in the rearing diets of two treatment groups of rescued herring gull chicks. Each diet was randomly assigned to each of the 27 captive-reared chicks for the duration of the study. We tested chicks’ individual food preferences throughout their development in captivity using food arrays with four food choices (fish, cat food, mussels and brown bread). Regardless of the dietary treatment group, we found that all chicks preferred fish and almost all refused to eat most of the bread offered. Our findings suggest that early-life diet, manipulated by the ratio of time the different foods were available, did not influence gull chicks’ food preferences. Instead, chicks developed a strong and persistent preference for marine foods, which appears to match adult gulls’ dietary switch to marine foods upon chick hatching and may reinforce the provisioning of marine foods during chick development. However, whether chicks in the wild would refuse provisioned foods, and to a sufficient extent to influence parental provisioning, requires further study. Longitudinal studies of urban animal populations that track wild individuals’ food preferences and foraging specialisations throughout life are required to shed light on the development and use of anthropogenic resource exploitation.
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Golet, Gregory H., Katherine J. Kuletz, Daniel D. Roby, and David B. Irons. "Adult Prey Choice Affects Chick Growth and Reproductive Success in Pigeon Guillemots." Auk 117, no. 1 (2000): 82–91. http://dx.doi.org/10.1093/auk/117.1.82.
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AbstractPigeon Guillemots (Cepphus columba) are diving seabirds that forage near shore and feed their chicks demersal and schooling fishes. During nine years between 1979 and 1997, we studied chick diet, chick growth rate, and reproductive success of Pigeon Guillemots at Prince William Sound, Alaska, to determine factors limiting breeding populations. We found evidence for prey specialization among breeding pairs and detected differences in reproductive success between specialists and generalists. Pairs that specialized on particular prey types when foraging for their chicks fledged more chicks than those that generalized, apparently because they delivered larger individual prey items. Reproductive performance also varied among guillemot pairs as a function of the proportion of high-lipid schooling fishes fed to the chicks. Pairs that delivered primarily high-lipid fishes (Pacific sand lance [Ammodytes hexapterus] and Pacific herring [Clupea pallasii]) had higher overall reproductive success than pairs that delivered primarily low-lipid demersal fishes (e.g. sculpins, blennies, stichaeids, and pholidids) and gadids. The proportion of high-lipid fishes in the diet was positively related to chick growth, suggesting that piscivorous seabird chicks benefit from eating species with high-energy densities during development. The diet of Pigeon Guillemot chicks showed high annual variation from 1979 to 1997, presumably because of fluctuations in abundance of Pacific sand lance, a high-lipid schooling fish. Regression analyses suggest that the percent occurrence of high-lipid fishes in the diet affected chick growth rate at the population level. We conclude that Pigeon Guillemots benefit by specializing when selecting prey for their chicks, and that high-lipid schooling fishes enhance chick growth and reproductive success.
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Gaston, Anthony J. "Influence of Chick Mass and Date at Departure from the Colony on Adult Characteristics in Ancient Murrelets (Synthliboramphus Antiquus), A Precocial Seabird." Auk 120, no. 3 (2003): 818–26. http://dx.doi.org/10.1093/auk/120.3.818.
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Abstract I investigated the effect of mass and date of departure of Ancient Murrelet (Synthliboramphus antiquus) chicks reared at two colonies in Haida Gwaii, British Columbia, on aspects of their adult biology. Chicks were captured, banded, and weighed while departing from their natal colony at two to three days old, during 1984–1998. Adults were recaptured at the same colonies during the breeding seasons of 1986–2000. Just under 1% of 13,055 chicks were recaptured as adults. Chicks that were heavier than average at colony departure were recaptured as adults at a younger age and were heavier as breeders than lighter chicks. However, chick departure mass did not affect adult mass of birds recaptured as nonbreeders. The date at which chicks left the colony had no effect on either adult mass or age at recapture. Correlation between chick mass at colony departure and adult mass as a breeder is rarely reported and is difficult to explain. However, if chick mass is determined by reproductive investment on the part of the parents and adult mass is a measure of reproductive investment by the individual, the correlation suggests that degree of parental investment could be a heritable trait.
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Colwell, Mark A., Susan J. Hurley, James N. Hall, and Stephen J. Dinsmore. "Age-Related Survival and Behavior of Snowy Plover Chicks." Condor 109, no. 3 (2007): 638–47. http://dx.doi.org/10.1093/condor/109.3.638.
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AbstractAbstract. Precocial young often experience high mortality prior to achieving flight, especially in the first days after hatching. We quantified relationships between chick age, survival, behavior, and response to natural and anthropogenic danger for the threatened Western Snowy Plover (Charadrius alexandrinus nivosus) in coastal northern California, USA. Plover chicks were most likely to die in the first three days of their 28-day prefledging period, especially on sandy ocean beaches compared to coarser substrates of river habitats. Chick survival in both habitats increased across the ∼120-day chick-rearing period. Improved survival of older chicks coincided with an age-related reduction in brooding and increased distance from the tending parent, which was not related to season. Lower survival of younger chicks was correlated with a tendency to lie motionless when approached by humans; nearly all older chicks responded to human approach by running to evade danger. Chicks of all ages were more likely to lie motionless when potential avian predators flew nearby. Age-dependent survival of Snowy Plover chicks paralleled a trend of increasing development, thermal independence from adults, and capability of evading predators.
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Lees, Daniel, Tom Schmidt, Craig D. H. Sherman, et al. "An assessment of radio telemetry for monitoring shorebird chick survival and causes of mortality." Wildlife Research 46, no. 7 (2019): 622. http://dx.doi.org/10.1071/wr18030.
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Abstract ContextMonitoring survival of free-living precocial avian young is critical for population management, but difficult to achieve. Perhaps the most promising technique available to track survival is the deployment of devices such as radio-transmitters or data loggers, which allow for tracking of the individuals. AimsTo understand if the deployment of radio-transmitters or the process of radio-tracking negatively impact chick survival by analysing survival of tagged chicks. MethodsFifty masked lapwing (Vanellus miles), 42 red-capped plover (Charadrius ruficapillus) and 27 hooded plover (Thinornis cucullatus) chicks were radio-tracked. Mortality between tagged and untagged chicks within broods was compared to examine whether radio-telemetry influenced chick survival. Key resultsThere was no statistically significant difference in survival between chicks with and without radio-transmitters. Radio-transmitters enabled the determination of cause of death for 0–28% of radio-tagged chicks. ConclusionThe survival of shorebird chicks does not appear to be affected by attachment of transmitters. ImplicationsRadio-tracking remains a promising way of studying the movement and survival of shorebird chicks, and is helpful but not reliable for assigning the cause of mortality.
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Chaplin, Susan B., Mora L. Cervenka, and Alison C. Mickelson. "Thermal Environment of the Nest During Development of Tree Swallow (Tachycineta bicolor) Chicks." Auk 119, no. 3 (2002): 845–51. http://dx.doi.org/10.1093/auk/119.3.845.
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Abstract We continuously recorded temperatures of the nest cup (Tn) and air (Ta) just outside the nest box throughout development of Tree Swallow (Tachycineta bicolor) chicks in east-central Minnesota. Brood size was manipulated (three or six chicks per nest) to study the effect of number of chicks in the nest on its thermal environment. From day 0 to day 4, Tn paralleled Ta, approximately 2–7°C higher, with nocturnal Tn maintained at 24°C and daytime Tn maintained at 26°C. From day 6 to day 12, Tn was relatively constant throughout the day, maintained at 32°C (day) and 29°C (night). The Tn became increasingly independent of Ta, as determined by regression analysis of Tn versus Ta with age. Nocturnal Tn of larger clutches (six chicks) was ∼2°C warmer than smaller clutches (three chicks), and Tn of larger clutches exhibited greater independence from Ta at day 10 than in smaller clutches. The occurrence of nest homeothermy at day 10 in six-chick nests correlates with near-maximal body mass of chicks and completion of feather insulation. Small (three-chick) clutches showed greater dependence of Tn on Ta at 10–12 days of age than large (six-chick) clutches; we propose that development of thermoregulatory capacity may have proceeded more slowly in chicks from those nests.
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Vigo-Trauco, Gabriela, Rony Garcia-Anleu, and Donald J. Brightsmith. "Increasing Survival of Wild Macaw Chicks Using Foster Parents and Supplemental Feeding." Diversity 13, no. 3 (2021): 121. http://dx.doi.org/10.3390/d13030121.
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The use of foster parents has great potential to help the recovery of highly endangered bird species. However, few studies have shown how to successfully use these techniques in wild populations. Scarlet Macaws (Ara macao macao) in Perú hatch 2–4 chicks per nest but about 24% of all chicks die of starvation and on average just 1.4 of them fledge per successful nest. In this study we develop and test new techniques to increase survival of wild Scarlet Macaw chicks by reducing chick starvation. We hypothesized that using foster parents would increase the survival of chicks at risk of starvation and increase overall reproductive success. Our results show that all relocated macaw chicks were successfully accepted by their foster parents (n = 28 chicks over 3 consecutive breeding seasons) and 89% of the relocated chicks fledged. Overall, we increased fledging success per available nest from 17% (2000 to 2016 average) to 25% (2017 to 2019) and decreased chick death by starvation from 19% to 4%. These findings show that the macaw foster parents technique and post relocation supplemental feeding provide a promising management tool to aid wild parrot population recovery in areas with low reproductive success.
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La Sala, L. F., A. M. Perez, J. E. Smits, and S. R. Martorelli. "Pathology of enteric infections induced by the acanthocephalan Profilicollis chasmagnathi in Olrog's gull, Larus atlanticus, from Argentina." Journal of Helminthology 87, no. 1 (2011): 17–23. http://dx.doi.org/10.1017/s0022149x11000721.
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AbstractAcanthocephalans can be pathogenic helminths of marine birds. Every year during the breeding season, there is variable mortality among prefledged chicks from the largest known Olrog's gull (Larus atlanticus) colony. Mortality has been associated with infection by the acanthocephalan Profilicollis chasmagnathi. Our aim was to study the role of chicks' size as a risk factor for intensity of infection and severe pathology, and to expand upon previous pathological findings reported in acanthocephalan-infected chicks. Size of the chick was associated with intensity of infection and number of intestinal perforations, which increased by 6.9% and 4.1%, respectively, for each millimetre increment in chick size. Infection was associated with inflammatory enteritis and granulomatous peritonitis. Complete intestinal perforations were observed in 85% and 97.3% of the studied chicks in 2005 and 2006, respectively, and they were observed very early during the post-hatching period. Our results show: (1) the presence of advanced pathology associated with acanthocephalan infections in chicks, beginning very early in the post-hatching period; and (2) significant increases in the intensity of infection and the associated pathology as a function of size of chicks, in dead chicks during this period.
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Oro, Daniel, and Meritxell Genovart. "Testing the intergenerational conflict hypothesis: factors affecting adoptions in Audouin's gulls, Larus audouinii." Canadian Journal of Zoology 77, no. 3 (1999): 433–39. http://dx.doi.org/10.1139/z98-218.
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We studied chick adoption in Audouin's gull, Larus audouinii, a ground-nesting seabird, to test several predictions made by the intergenerational-conflict hypothesis (ICH). The effects of food availability on adoptions were considered by comparing two breeding seasons with differing food supply. As predicted, adoptions were significantly more frequent when food was in shorter supply (48% of broods affected) than when it was more available (18.5%). Adoptions occurred during the first week of the chick-rearing stage; after that, aggression by adults towards intruding chicks increased significantly, which suggests that mechanisms of parent-offspring recognition were established. Foster parents incurred certain costs, since their offspring had lower chances of survival than those in control broods. However, contrary to the ICH hypothesis, adoptees did not select foster broods in relation to the age of the resident chicks. Survival of wandering chicks was no higher than that of chicks who stayed in their natal brood. Results suggest that chicks move only as a response to neighboring chicks being fed by an adult, and in Audouin's gulls, adoptions might be considered reproductive errors.
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G.E.O., Makinde, Agbato O., Awoyinka O.F., and Fasanmi O.G. "Quality Assessment of Broiler and Pullet Day-Old Chicks Hatched in Ibadan, Oyo State." African Journal of Agriculture and Food Science 6, no. 2 (2023): 75–85. http://dx.doi.org/10.52589/ajafs-i1vnyn4x.
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The quality of day-old chicks determines the foundation and performance of a flock on the farm. This study randomly selected five-day-old chicks from 8 commercial hatcheries within the Ibadan metropolis to assess the quality of day-old broilers and pullets produced. The chicks were subjected to physical examination and microbial screening. Physical parameters checked include chick weight, chick length and agility, while organ swabs cultured produced the following microbes viz., coliform and non-coliform bacteria, Escherichia coli, Shigella sp, Salmonella sp and Proteus sp.` The result shows that there were significant effects (P<0.05) of sources on chick body weight, with highest (39.66±0.54g) and lowest (31.80±0.54g), chick body length with highest (17.10±0.17cm) and lowest (13.70±0.17cm), and chick agility with lowest time (0.20±0.03min) and highest time (0.50±0.03min). In most of the hatcheries surveyed, microbial isolates are too numerous to count, which is an indication of contamination due to poor hygiene and sanitation in and around the hatcheries. This will have a negative effect on the quality of the chicks produced and hence their performance. It is hereby recommended that hatcheries should improve on-farm and hatchery hygiene and biosecurity.
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Nowak, B., E. Pawlina, K. Ilska, A. Mucha, and W. Kruszynski. "Breeder line and age affects the occurrence of developmental defects, the number of culled one-day old broiler chicks and their body mass." Veterinární Medicína 64, No. 7 (2019): 323–33. http://dx.doi.org/10.17221/137/2018-vetmed.
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The objective of this work was to study the reasons for culling one-day old broiler chicks and to examine the relationship between the age and line of the hens and the culled chick’s body mass. Hatching eggs and day-old chicks were collected from a commercial flock of the Cobb 500 and Ross 308 broiler lines. The eggs were collected when the hens were 32, 42 and 52 weeks old. The reasons for culling the chicks were assessed immediately after the chicks had been removed from the hatcheries. The four main groups of defects were distinguished, depending on the part of the chick’s body. A fifth group covered general developmental defects. Within each group, the structural defects were identified in detail. The statistical analysis was performed in the R project. Amongst 57 600 chicks evaluated, 1042 malformations disqualifying them from further rearing were found in 666. The most frequent developmental defects were associated with the structure of the abdominal wall and umbilical cord: these were found in 155 chicks from the Ross 308 line and in 107 from the Cobb 500 line. In turn, umbilical defects occurred in 95 and 104 chicks from the Ross 308 and Cobb 500 lines, respectively. Abdominal defects were the most common in 107 chicks from the 42-week-old layers and in 89 chicks from the 52-week-old layers. There were also correlations between the age of the parent flock and the following defects: glued down, lack of down on the wings, contorted hips, wry neck and spine, and lack of a wake-up reflex. The average body weights of the Ross 308 and Cobb 500 chicks were 44.00 g and 43.13 g, respectively, but these differences were not statistically significant. However, the age of the broiler breeders (42 or 52 weeks) did affect the chick’s body weight (P ≤ 0.05). The lightest chicks (40.75 g) came from the Ross 308 line (age 42 weeks) and were nearly 4 g lighter than all the other groups. Most relationships between the lines of the layer hens at a particular age and the occurrence of malformations in the chicks were found in the hens aged 32 weeks, which may indicate the need for changes in the management of the eggs from the youngest layers belonging to the different lines.
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Russell, James C., Jemma R. Welch, Rob Dunn, and Karen Bourgeois. "Chick Provisioning in Grey-Faced Petrel (Pterodroma gouldi) under Environmental Stress." Birds 3, no. 3 (2022): 285–92. http://dx.doi.org/10.3390/birds3030019.
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Grey-faced Petrels (Pterodroma gouldi) are colonial burrowing seabirds predominantly nesting on offshore islands of the upper North Island of New Zealand. We studied their chick provisioning on Te Hāwere-a-Maki during two years of unfavourable warmer La Niña conditions in 2011 and 2013. We intensively monitored chicks in each year, weighing chicks every 12 h for 10 consecutive days to estimate meal sizes following chick provisioning and to estimate 12-hourly body mass loss as a function of time since last feeding. We found a quadratic relationship of body mass loss with time since last feeding, with rapid digestion of meals following provisioning followed by a period of fasting from five days post feeding as chicks waited an unknown and variable amount of time until their next meal. The rate of body mass loss did not depend on chick age nor body mass, and did not differ between years, but heavier chicks included in our study were more likely to successfully fledge, suggesting a legacy of adult provisioning prior to our study commencing. Our regular handling of chicks for monitoring has no discernible impact on parent provisioning compared to a set of control chicks. The mean estimates of 100-gram meal sizes and 10-day foraging trip durations are likely to be below the break-even point for this species.
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Durmuş, Murat, Kadriye Kurşun, Mikail Baylan, and Hasan Rüştü Kutlu. "Ross 308 Etlik Piliçlerde Damızlık Yaşının Kuluçka Sonuçları ve Civciv Kalitesi Üzerine Etkisi." Turkish Journal of Agriculture - Food Science and Technology 9, no. 2 (2021): 362–67. http://dx.doi.org/10.24925/turjaf.v9i2.362-367.4005.
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The present study was planned to determine the effect of flock age on hatching results and chick quality in Ross 308 broiler parents. For this purpose, the eggs of three different flock age (30, 47, and 59 weeks of age) were used. A total of 450 eggs (50 × 3 for each group), including 150 eggs from each age group, were placed in the incubator as a coincidence. The number of alive chicks after hatching was determined and these chicks were classified into three quality groups as low quality, high quality, and discarded chicks. Non-hatched eggs were broken in order to control the fertility and determine the embryonic deaths. At the end of the study, the effect of the flock age on fertility rate (%), hatchability (%) and chick quality was found to be significant. However, the effect of flock age on hatchablity of fertile eggs and early, mid, and late-period embryo deaths were found to be insignificant. It was found that eggs obtained from the young breeders were higher in terms of fertility rate and hatchability than eggs obtained from old breeders. The chicks obtained from young breeders' eggs were determined as 33.60% high quality, 48.10% low quality, and 18.30% discarded chicks. These rates were 32.70%, 43.40%, and 23.90% in chicks obtained from middle-aged breeders, respectively, 56.10%, 36.40%, and 7.50% in chicks obtained from the old breeders. As a result, it was determined that there was a decrease in the hatching results in parallel with the increase in breeding age, but the chick quality increased.
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Samelius, Gustaf, and Ray T. Alisauskas. "Diet and growth of glaucous gulls at a large Arctic goose colony." Canadian Journal of Zoology 77, no. 8 (1999): 1327–31. http://dx.doi.org/10.1139/z99-091.
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We examined the diet and growth of glaucous gull (Larus hyperboreus) chicks at Karrak Lake goose colony in 1994 and were especially interested in how these factors were affected by geese leaving the colony after goose hatch. Insects and bird prey each occurred in about 80% of regurgitated pellets during the first week after hatch of gulls. Thereafter, the frequency of insects in pellets diminished to <20%, whereas the frequency of bird parts and eggshells increased to about 100 and 80%, respectively, and remained high in gull diets during the 6 weeks of this study. We observed no effect of laying order on the size of gull eggs, nor any effects of chick sequence on growth or survival of chicks, suggesting that food was abundant during egg-laying and possibly early in chick rearing. Overall, both the growth rate and final size of chicks varied among nests, and chicks from small broods grew larger than chicks from large broods. Egg size and hatch date had no effect on growth. We suspect that brood size emerged as an important effect on growth, because food abundance declined as gull chicks grew older and brood competition came in to play.
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Linhoss, John E., Joseph L. Purswell, and Jeremiah D. Davis. "Radiant Flux Preference of Neonatal Broiler Chicks During Brooding." Transactions of the ASABE 61, no. 4 (2018): 1417–23. http://dx.doi.org/10.13031/trans.12775.
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Abstract. Radiant heat is the most common method of providing supplemental heat in a broiler house. However, little information exists about chick preference for radiant flux. Identifying the ranges of radiant flux that chicks prefer would allow improved management of the thermal environment. The objectives of this study were to determine the radiant flux ranges preferred by broiler chicks during the first eight days of brooding. Three trials were conducted using straight-run broiler chicks. A total of 88 chicks were randomly allocated into two mixed-gender groups and placed into identical 1 m × 4 m pens for 8 d. Heat lamps were used to create radiant flux zones of 30, 70, 175, and 450 W m-2 in each pen. Chicks were allowed to move freely between the zones, and feed and water were available in each treatment area. Chick location was recorded with a camera at 5 min intervals. For each image, non-linear regression analysis was applied to the cumulative proportion of chicks in each treatment. The resulting equations were used to calculate the range of radiant flux values for which 80% of the chicks exhibited a preference. Chicks exhibited a preference for decreasing radiant flux with age. The mean maximum preferred radiant flux for all trials decreased from 409.4 W m-2 at 1 d to 304.4 W m-2 at 8 d. The mean minimum preferred radiant flux for all trials decreased from 114.5 W m-2 at 1 d to 31.4 W m-2 at 8 d. Keywords: Broiler chicks, Brooding, Radiant flux, Radiant heaters, Thermal preference.
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Ritchie, Branson W., Frank D. Niagro, Kenneth S. Latimer, et al. "Antibody response to and maternal immunity from an experimental psittacine beak and feather disease vaccine." American Journal of Veterinary Research 53, no. 9 (1992): 1512–18. http://dx.doi.org/10.2460/ajvr.1992.53.09.1512.
Full textAbstract:
SUMMARY Adult umbrella cockatoos, Moluccan cockatoos, African grey parrots, and a yellow-headed Amazon parrot were inoculated im or sc with β-propiolactone-treated psittacine beak and feather disease (pbfd) virus. Thirty- to 45-day-old African grey parrot, umbrella cockatoo, and sulphur-crested cockatoo chicks also were vaccinated with the same inoculum. The hemagglutination inhibition (hi) and agar-gel diffusion tests were used to assay for post-vaccination development of anti-pbfd virus antibodies. All adult vaccinates seroconverted and had increases in hi and precipitating antibodies. The vaccinated chicks had increased concentrations of hi antibodies, but precipitating antibodies could not be detected. To demonstrate that chicks from vaccinated hens are protected from pbfd virus challenge, 3 African grey parrot chicks and 2 umbrella cockatoo chicks from vaccinated hens and 1 African grey parrot chick and 1 umbrella cockatoo chick from nonvaccinated hens were exposed to purified pbfd virus. Chicks from the vaccinated hens remained clinically normal during the 50-day test period. Chicks from the nonvaccinated hens developed clinical and histologic lesions of pbfd. Infected tissues from these birds were confirmed to contain viral antigen, using immunohistochemical staining techniques. The pbfd virus was recovered from the affected birds. These findings indicate that adult and 30- to 45-day-old psittacine birds will seroconvert following vaccination with β-propiolactone-treated pbfd virus. Also, hens inoculated with β-propiolactone-treated pbfd virus produce chicks that are, at least temporarily, resistant to virus challenge.
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Barham, Peter J., Les G. Underhill, Robert J. M. Crawford, et al. "The efficacy of hand-rearing penguin chicks: evidence from African Penguins (Spheniscus demersus) orphaned in the Treasure oil spill in 2000." Bird Conservation International 18, no. 2 (2008): 144–52. http://dx.doi.org/10.1017/s0959270908000142.
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AbstractSome 2,000 orphaned chicks of African Penguins Spheniscus demersus were hand-reared and released back into the wild on Robben and Dassen Islands following the Treasure oil spill in June 2000. Of these chicks, 1,787 were flipper banded. This paper reports on the subsequent survival rate and breeding success of those individuals seen on Robben Island from 2001–2006. Survival to breeding age and their subsequent breeding success of hand-reared chicks was no different from that of naturally-reared chicks. Over a four-year period, pairs where at least one partner was a hand-reared chick produced an average of more than 1.6 chicks per year. Combining the data on survival with that on breeding success indicates that 1,000 hand-reared chicks will produce around 1,220 chicks themselves over their lifetimes, making this a worthwhile conservation intervention.
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Golet, Gregory H., David B. Irons, and Daniel P. Costa. "Energy costs of chick rearing in Black-legged Kittiwakes (Rissa tridactyla)." Canadian Journal of Zoology 78, no. 6 (2000): 982–91. http://dx.doi.org/10.1139/z00-026.
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We studied energy expenditure in adult Black-legged Kittiwakes (Rissa tridoctyla) with doubly labeled water to measure energy costs of chick rearing. We removed eggs from randomly selected nests and compared energy expenditure late in the chick-rearing period between adults raising chicks and adults whose eggs had been removed. Adults raising chicks expended energy at a rate 21% higher than adults from manipulated nests, apparently owing to differences in activity patterns while away from the colony. No sex-specific differences were detected in energy costs of chick rearing or energy expenditure, although statistical power for these analyses was fairly low. Among the unmanipulated group, energy expenditure tended to be positively related to natural brood size. An ancillary goal of our study was to test hypotheses that describe how population-level field metabolic rates (FMRs) vary during chick rearing. We compared FMRs among kittiwakes raising chicks at a colony in Alaska (61°09'N) with those reported for a colony in Norway (76°30'N). FMRs of adults raising chicks were nearly identical at the two colonies, suggesting that adults may have preferred levels of energy expenditure during chick rearing that are relatively invariant with environmental conditions, and that are not adjusted according to adult survival probabilities.
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Shanker, S., A. Lee, and T. C. Sorrell. "Experimental colonization of broiler chicks withCampylobacter jejuni." Epidemiology and Infection 100, no. 1 (1988): 27–34. http://dx.doi.org/10.1017/s0950268800065523.
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SUMMARYMinimal colonization inocula for two broiler strains ofCampylobacter jejuniwere determined in broiler chicks aged 2–3 days and 2 weeks. Individually housed chicks were exposed to a single oral or cloacal challenge. Diarrhoeal symptoms were absent in all 380 chicks included in the study. Chick susceptibility to the twoC. jejunistrains varied. Colonization was effected by < 102−104colony forming units (c.f.u.) via cloacal challenge and 104–106c.f.u. via the oral route. Colonization inocula for 2-to 3-day and 2-week-old chicks were similar. Treatment of 1-day-old chicks with fresh adult caecal flora or an anaerobic broth culture of adult caecal flora did not inhibit colonization after challenge with low-doseC. jejuni. Susceptible chicks were colonized rapidly.C. jejuniwas detected in 167 of 189 (88%) colonized chicks within 3 days of challenge and persisted during the 2-week monitoring period. Our data suggest that colonization of broiler chicks withC. jejuniis effected more easily by the cloacal than the oral route and is independent of age.
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Tveraa, Torkild, and Guttorm N. Christensen. "Body Condition and Parental Decisions in the Snow Petrel (Pagodroma Nivea)." Auk 119, no. 1 (2002): 266–70. http://dx.doi.org/10.1093/auk/119.1.266.
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Abstract In Procellariiformes, parents guard the chick for some time after it has attained homeothermy. Such a strategy may have evolved to protect the chick from predation or inclement weather, but it is costly because only one parent can forage at a time. Therefore, the decision to leave the chick seems to be a trade-off between the chick's ability to care for itself, body condition of the parent present at the nest, and ability of the bird out foraging to return to the nest before its mate's body condition has degraded. We studied chick growth and survival together with number of days Snow Petrel (Pagodroma nivea) chicks were guarded before being left alone for the first time in relation to the parents body condition and ability to return to the nest in time. Parents in good body condition were more likely to produce a chick that survived the guard stage. They also guarded their chick for a longer period (range 2–8 days, x̄ = 4.5) and finally left it alone with a higher body mass than those in poor body condition. However, whether the foraging bird was able to return to the nest in time to relieve its mate was also strongly related to number of days the chick was guarded and its body mass. The chicks' survival from when they were left alone and until day 10 posthatch was positively related both to number of days they were guarded and their body condition (body mass corrected for age).
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Qu, James S., and Jennifer Davis. "Distribution of Parental Investment and Sibling Competition in the Herring Gull, Larus Argentatus." Behaviour 134, no. 13-14 (1997): 961–74. http://dx.doi.org/10.1163/156853997x00331.
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AbstractHerring gulls, Larus argentatus, typically lay three eggs. The third laid egg is smaller, hatches later, and hatches a lighter, smaller chick than the first two. The third hatched chick also has a lower chance of survival. Observations of parent-chick and chick-chick interactions were conducted at two Ontario sites in the Great Lakes to determine whether and how parents might behaviorally bias investment in their chicks after the incubation period, and how interactions among chicks might add to the third chick disadvantage. Little evidence was found for behavioral discrimination against the third chick by either its parents or its siblings. The last hatched (C) chick was not less likely than its older siblings (A or B) to get to the food first, and while A and B were more likely to target C when initiating tugs-of-war over food, they were not more likely than C to initiate tugs-of-war in general. C pecked siblings the most, and, despite its younger age and smaller size, was not more likely to lose tugs-of-war with its siblings. It is likely that the locations where this study was conducted represent relatively benign environment in which to raise chicks compared to the marine populations observed in other studies. Given this, parents might be expected to reduce chick asymmetries if they are able. There was a high degree of hatching synchrony in Hamilton Harbor. In 7 out of 28 nests the C chick hatched on the same day as the B or A and B chicks.
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Seal, Hayley E., Sigmund J. Lilian, Anastas Popratiloff, June C. Hirsch, and Kenna D. Peusner. "Implementing the chick embryo model to study vestibular developmental disorders." Journal of Neurophysiology 122, no. 6 (2019): 2272–83. http://dx.doi.org/10.1152/jn.00434.2019.
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Children with congenital vestibular disorders show delayed motor development and challenges in maintaining posture and balance. Computed tomography images reveal that these children have abnormal inner ears in the form of a sac, with the semicircular canals missing or truncated. Little is known about how this inner ear abnormality affects central vestibular development. At present, mice with the chromodomain helicase DNA-binding protein 7 mutation are the most common model for studying congenital vestibular disorders, despite forming multiple diverse inner ear phenotypes and inducing abnormal cerebellar and visual system development. To identify the effects of a sac-like inner ear on central vestibular development, we have designed and implemented a new model, the anterior-posterior axis rotated otocyst (ARO) chick, which forms a sac-like inner ear in 85% of cases. The ARO chick is produced by anterior-posterior rotation of the otocyst at embryonic day 2. Here, we describe for the first time the 15% of ARO chicks that form three small semicircular canals and rename the ARO chicks forming sacs (ARO/s chicks). The basic features of the vestibular sensory organs in ARO/s chicks are similar to those found in patients’ sacs, and ARO/s hatchlings experience balance and walking problems like patients. Thus, ARO/s chicks have a reproducible inner ear phenotype without abnormalities in vestibular-related structures, making the model a relatively simple one to evaluate the relationship between the sac-like inner ear pathology and formation of the central vestibular neural circuitry. Here, we describe unpublished details on the surgical approaches to produce ARO chicks, including pitfalls and difficulties to avoid. NEW & NOTEWORTHY This paper describes simple techniques for chick otocyst rotation resulting in a sac-like inner ear (85%), the common phenotype in congenital vestibular disorders. We now describe anterior-posterior axis rotated otocyst chicks, which form three small canals (15%), and rename chicks forming a sac (ARO/s chicks). Basic protocols and potential complications of otocyst rotation are described. With the use of ARO/s chicks, it will be possible to determine how the vestibular neural circuit is modified by sac-like inner ear formation.
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Ricklefs, Robert E. "Response of Adult Leach's Storm-Petrels to Increased Food Demand at the Nest." Auk 104, no. 4 (1987): 750–56. http://dx.doi.org/10.1093/auk/104.4.750.
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Abstract In a colony of Leach's Storm-Petrels (Oceanodroma leucorhoa) on Kent Island, New Brunswick, i chicks were rotated on a daily basis through n nests to produce i/n chick-equivalents of food requirement, increasing by small increments from 1 (i = 6, n = 6) to 2 (i = 2, n = 1), between ages 10 and 50 days. Food delivered each night (SUM) was estimated by 24-h increments in chick mass. In nonexperimental nests SUM varied significantly among pairs, and chick mass varied in direct relation to SUM. Adults tending experimental nests did not respond to increased food demand, and chick mass decreased with increasing chick-equivalent per nest. After rotations were terminated, the mass of most chicks increased quickly to normal levels. These results suggest that the average amount of food delivered daily by each parent is determined independently of food demand and that chicks attain a mass that balances a fixed food intake against food requirement, which varies in direct relation to mass.
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Mermoz, Myriam E., and Juan C. Reboreda. "Reproductive Success of Shiny Cowbird (Molothrus Bonariensis) Parasitizing the Larger Brown-and-Yellow Marshbird (Pseudoleistes Virescens) in Argentina." Auk 120, no. 4 (2003): 1128–39. http://dx.doi.org/10.1093/auk/120.4.1128.
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Abstract Shiny Cowbirds (Molothrus bonariensis) often parasitize larger hosts. It has been proposed that larger hosts are preferred by that parasite because they provide higher reproductive success, but available data are quite variable. We studied the reproductive success of Shiny Cowbirds in nests of Brown-and-yellow Marshbirds (Pseudoleistes virescens), a larger and often multiply parasitized host. To estimate the extent of interspecific competition, we compared the hatching success of parasite eggs in nests with and without reduction of the clutch size of the host as a result of egg punctures inflicted by the parasite, and the survival and growth of parasite chicks reared with and without host chicks. To estimate the extent of intraspecific competition, we compared Shiny Cowbird egg losses, hatching success, and chick survival in singly versus multiply parasitized nests. Reproductive success of Shiny Cowbirds was 8% with depredation causing 80% of losses. Clutch reduction due to egg punctures were higher in multiply than in singly parasitized nests, but it did not improve hatching success of parasite eggs. Neither survival nor growth of parasite chicks was affected by the presence of host chicks. Shiny Cowbird hatching success and chick survival did not differ between singly and multiply parasitized nests. Parasite chicks were smaller than same-age Brown-and-yellow Marshbird chicks. However, because parasite chicks hatched one or two days before host chicks and had a higher growth rate, they were the larger chicks in the nest. Overall Shiny Cowbird reproductive success in Brown-and-yellow Marshbird nests was apparently higher than that reported in other smaller or similar-sized hosts. We think that host life-history traits like large clutch size, a longer incubation period, and slower growth rate of chicks are responsible for the high reproductive success of Shiny Cowbirds with Brown-and-yellow Marshbirds.
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Nakazawa, Ken, Yutaka Kusuya, and Koki Shigenobu. "Developmental increase in the inotropic and cyclic AMP response to isoproterenol in embryonic and newly hatched chicks." Canadian Journal of Physiology and Pharmacology 67, no. 9 (1989): 1109–11. http://dx.doi.org/10.1139/y89-176.
Full textAbstract:
The cyclic adenosine 3′,5′-monophosphate (cyclic AMP) levels of ventricles isolated from 15- to 20-day-old chick embryos and 0- to 3-day-old hatched chicks were compared to clarify the mechanism underlying the change in sensitivity to isoproterenol during perinatal developmental stages when the functional sympathetic innervation has been completely achieved. Isoproterenol produced a positive inotropic effect on ventricles isolated from both embryonic and hatched chicks, but the ventricles from the hatched chicks were more sensitive. At both developmental stages sotalol was an equipotent antagonist of isoproterenol. 3-Isobutyl-1-methylxanthine (IBMX) produced an increment in the contractile force of the ventricles at both stages, but the ventricles from the hatched chicks responded to lower doses of IBMX. The reactivity to isoproterenol in increasing cyclic AMP level was significantly higher in the hatched ventricles than in the embryonic ventricles. The results suggest that the different sensitivities to isoproterenol between embryonic and newly hatched chick ventricles may be due to some changes in the process for cyclic AMP production.Key words: chick ventricle, development, β-adrenergic sensitivity, cyclic AMP.
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Gaglo-Disse, Adjovi, Kokou Tona, Sakibou Aliou, et al. "Effect of delayed feed access on production and blood parameters of layer-type chicks." Acta Veterinaria Hungarica 58, no. 2 (2010): 211–19. http://dx.doi.org/10.1556/avet.58.2010.2.7.
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A total of 684 Hisex Brown day-old chicks were studied. The chicks were randomly assigned into three groups as follows: (1) chicks with immediate feed access; (2) chicks with 48 h delay in feed access, and (3) chicks with 72 h delay in feed access. For each group, chicks were assigned into 4 replications of 57 birds each. Prior to feed access, the chicks were weighed. Samples of chicks were used to weigh yolk sac at 1, 3 and 7 days and to collect blood at 1, 3, 7, 14 and 56 days. Also, reared chicks were weighed weekly. The results indicated that chick weights decreased during the holding period. Yolk sac utilisation was similar between groups, while morbidity and mortality increased linearly with the duration of delay in feed access. At 56 days, chicks having delayed access to feed were lighter than those without delay in feed access. Serum concentration of glucose up to 14 days and of total protein and triglycerides until 56 days decreased with the increasing duration of delay in feed access. It can be concluded that delayed feed access is detrimental to the juvenile performance of layer-type chicks and has a negative age-related effect on the serum concentrations of glucose, triglycerides and total protein.
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Jeong, Min-Su, Chang-Young Choi, Woo-Shin Lee, and Ki-Sup Lee. "Age-dependent shifts and spatial variation in the diet of endangered Black-faced Spoonbill (Platalea minor) chicks." PLOS ONE 16, no. 7 (2021): e0253469. http://dx.doi.org/10.1371/journal.pone.0253469.
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The endangered Black-faced Spoonbill (Platalea minor) strictly breeds in marine environments and is threatened by the rapid loss of coastal wetlands within its breeding range. Adults with chicks are thought to gradually switch feeding sites from freshwater wetlands to coastal mudflats as the chicks’ osmoregulatory system develops. We investigated age-dependent shifts in the diet of Black-faced Spoonbill chicks at four breeding colonies with varying freshwater habitat availability by examining stable isotopes (δ13C, δ15N) between the tip (grown at the age of 10 days) and middle (grown at the age of 22 days) portions of their primary feathers. The δ13C value of the middle portions was significantly higher than that of the tips, which suggested that the ratio of marine resources increased with the growth and development of chicks. A Bayesian isotope mixing model revealed that the diet proportion of marine prey in the early-chick rearing season was slightly higher than in the late-chick rearing season at three colonies in inshore areas, although this proportion was approximately 60% even in the early chick-rearing period. In contrast, isotopic values and reconstructed diet composition suggested that chicks in an offshore colony with limited freshwater wetlands relied more heavily on freshwater diets for both chick-rearing periods (>80%). Our results suggest that the shifts in feeding sites seen in previous studies might be related to the age-dependent dietary shift of chicks, highlighting the importance of freshwater wetlands for spoonbills on offshore islands without an inflow of freshwater in nearby intertidal mudflats. These findings emphasize the importance of freshwater prey and wetlands even for the endangered marine-breeding spoonbills, even though the negative impact of salt stress remains inconclusive.
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Noh, Hee-Jin, Ros Gloag, and Naomi E. Langmore. "True recognition of nestlings by hosts selects for mimetic cuckoo chicks." Proceedings of the Royal Society B: Biological Sciences 285, no. 1880 (2018): 20180726. http://dx.doi.org/10.1098/rspb.2018.0726.
Full textAbstract:
Brood parasitic cuckoos lay their eggs in other birds' nests, whereafter the young cuckoo hatches, ejects its nest-mates and monopolizes the care of the host parents. Theory predicts that hosts should not evolve to recognize and reject cuckoo chicks via imprinting because of the risk of mistakenly imprinting on a cuckoo chick in their first brood and thereafter always rejecting their own chicks. However, recent studies have revealed that some hosts do reject cuckoo chicks from the nest, indicating that these hosts’ recognition systems either do not rely on first brood imprinting, or use cues that are independent of chick phenotype. Here, we investigate the proximate mechanisms of chick rejection behaviour in the large-billed gerygone ( Gerygone magnirostris ), a host of the little bronze-cuckoo ( Chalcites minutillus ). We find that gerygones use true template-based recognition based on at least one visual chick trait (the number of hatchling down-feathers), and that this is further mediated by experience of adult cuckoos at the nest during egg-laying. Given the theoretical constraints of acquiring recognition templates via imprinting, gerygones must possess a template of own-chick appearance that is largely innate. This true recognition has facilitated the evolution of very rapid hatchling rejection and, in turn, striking visual mimicry of host young by little bronze-cuckoo chicks.
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Gilliland, S. G., C. D. Ankney, and P. W. Hicklin. "Foraging ecology of Great Black-backed Gulls during brood-rearing in the Bay of Fundy, New Brunswick." Canadian Journal of Zoology 82, no. 9 (2004): 1416–26. http://dx.doi.org/10.1139/z04-124.
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We studied nesting ecology of Great Black-backed Gulls (Larus marinus L., 1758) in the Bay of Fundy, New Brunswick, in 1988 and 1989. We documented diet, feeding rate, and meal size for chicks from hatching to fledging. In 1989, colonies consisted of about 350 nests on five islands. Brood size declined with chick age, and by the end of the first week of the nestling period, 11%, 22%, 31%, and 36% of nests consisted of broods of 0, 1, 2, and 3 chicks, respectively. Average meals size increased and feeding frequency declined slightly with chick age. We estimated that 619.6 kg (dry mass) of food was fed to chicks during the nestling period in 1989. The composition of the chicks' diet changed with age and was most varied early in the nestling period, when they were fed relatively equal proportions of major food types. Overall, Atlantic herring (Clupea harengus L., 1758) was the most important prey item and contributed 63% of the energy consumed by chicks during the nestling period. Northern krill (Meganyctiphanes norvegica (M. Sars, 1857); 11.9%), lumpfish (Cyclopterus lumpus L., 1758; 10.4%), and waste (fisheries and domestic; 4.7%) were also important foods. Gull chicks and Common Eider (Somateria mollissima (L., 1758)) ducklings made up 1.9% and 0.8%, respectively, of the chicks' energy budget. We conclude that the primary factor effecting productivity of the Great Black-backed Gull was food availability, and the amount of food available varied little over the nesting period in 1989.
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Rossell, Jr., C. Reed, Christine D. Hamilton, Louise M. Weber, and Stephen W. Kress. "Chick provisioning by common terns in the southern Gulf of Maine, U.S.A." Canadian Journal of Zoology 78, no. 1 (2000): 158–60. http://dx.doi.org/10.1139/z99-184.
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We examined chick provisioning by common terns (Sterna hirundo) in relation to hatching order, chick stage, and weather on Stratton Island, Maine, U.S.A., during the summer of 1997. Provisioning rates, recorded at 10 nests during 30-min observation sessions (n = 256), were calculated for first-, second-, and third-hatched chicks in three age-classes (1-5, 6-10, and 11-15 days). Mean provisioning rates did not differ significantly with hatching order of chicks. However, a trend toward differential provisioning was evident during the earliest chick stage. Mean provisioning rates increased significantly from age-classs 1 to 2 and decreased significantly from age-classes 2 to 3. Weather had no significant effects on provisioning rates, owing to the unusually mild and consistent conditions. These results indicate that during the earliest chick stage, older siblings in a brood may have an advantage in obtaining food, even when weather conditions are highly favorable for provisioning chicks.
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Kent, J. P. "Experiments On the Relationship Between the Hen and Chick (Gallus Gallus): the Role of the Auditory Mode in Recognition and the Effects of Maternal Separation." Behaviour 102, no. 1-2 (1987): 1–13. http://dx.doi.org/10.1163/156853986x00018.
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AbstractIn a series of 6 experimental studies, the means by which a chick recognises its mother, and the reversibility of filial attachments were examined using bantam hens and their chicks. In a simultaneous discrimination test it was determined that the chick could discriminate between own and alien hens by means of the hens' cluck vocalizations, on the 4th and 8th days post hatching, (Experiment 1). The chicks could make this discrimination more efficiently when live hens were presented (Experiment 2). On separating the hen and chicks for 4 h on the 4th day, the chicks could no longer discriminate between own and an alien live hen (Experiment 3) while they would accept an alien hen, (Experiment 4). These findings suggest that maternal-filial bonds may be reversed with little difficulty. Thus Experiment 5 was designed to examine the stability of these later maternal filial bonds. Chicks spent the first 3 days post hatching, with the hen who incubated the eggs. Then they spent 3 days with an alien hen, after which 3 days isolation followed. It was found that chicks could discriminate in favour of their own hen after the first period of exposure, and in favour of the alien hen after the second period of exposure. Following 3 days isolation they showed no preference for either hen. Experiment 6 was essentially a replication of Experiment 5, but included a control for familiarity. Only one test took place after the 3 days isolation. The chicks were presented with the 1st 2nd and an unfamiliar alien hen. The chicks did not discriminate in favour of any particular hen. It is concluded that after 4 h or 3 days isolation, the chicks did not discriminate between the hens presented, yet they remained responsive to hens.
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Bogenschutz, Todd R., Chris S. Jennelle, Mark W. McInroy, and Steven D. Roberts. "Use of Surgical Tissue Adhesive and Body Mass Change to Assess Ring-necked Pheasant Brood Foraging Habitat." Journal of the Iowa Academy of Science 126, no. 1-4 (2019): 1–5. http://dx.doi.org/10.17833/0896-8381-126.1.1.
Full textAbstract:
Foraging rates (arthropod consumption [g/min/chick]) of human-imprinted chicks provide a reasonable metric for assessing the quality of brood-rearing habitats for gallinaceous species. Arthropod foraging rates have been estimated using dry mass or allometric equations of crop and gizzard contents, and internal surgical ligature of the crop. Current methods are time- and labor-intensive. We describe a new method to estimate foraging rate using chick mass change (g/min) during a 30-min foraging trial. Our technique requires surgical tissue adhesive be applied to the cloaca to prevent bias in mass change measurements caused by defecation. We compare our mass change technique to a published internal surgical ligature technique using human-imprinted ring-necked pheasant chicks. Chicks treated with tissue adhesive had rates of mass gain (0.012 g/min, SE = 0.004) similar to ligatured chicks (0.006 g/min, SE = 0.004, F1,58 = 3.16, P = 0.0805). In contrast to the surgical ligature procedure, we found tissue adhesives can be applied quickly in the field and provide an efficient means to evaluate foraging quality of brood-rearing habitats. We provide suggestions for a set of standardized protocols for the use of imprinted chicks.
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Cornec, C., Y. Hingrat, V. Planas-Bielsa, H. Abi Hussein, and F. Rybak. "Individuality in houbara chick calls and its dynamics throughout ontogeny." Endangered Species Research 47 (January 27, 2022): 61–73. http://dx.doi.org/10.3354/esr01163.
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In many taxa, breeding success depends heavily on reliable vocal recognition between parents and offspring. Although the acoustic basis of this recognition has been explored in several species, few studies have examined the evolution of acoustic cues to identity across development. Here, in a captive breeding program, we investigated for the first time the acoustic signals produced by North African houbara bustard Chlamydotis undulata undulata chicks. Two call types (contact and distress) were recorded from 15 chicks in 4 age classes. Acoustic analyses showed that the acoustic parameters of the calls varied systematically with age in both contact and distress calls. However, both call types remained highly stereotyped and individualized between chicks at every tested age, indicating that calls encode reliable information about individual identity throughout development, thus potentially enabling the mother to distinguish her own chicks through their development up to fledging. Playback experiments are now needed to verify such parent-chick recognition in houbara bustards and its efficiency across chick ontogeny.
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Bhanja, Subrat K., Asit Baran Mandal, Sushil K. Agarwal, and Samir Majumdar. "Modulation of post hatch-growth and immunocompetence through in ovo injection of limiting amino acids in broiler chickens." Indian Journal of Animal Sciences 82, no. 9 (2012): 993–98. http://dx.doi.org/10.56093/ijans.v82i9.23652.
Full textAbstract:
Early post-hatch growth and immunity was assessed through in ovo injection of some critical amino acids on 14th d of incubation at the broad end of the egg using 25 mm needle. Percent hatchability in lysine (lys) and arginine (arg) injected groups were better than un-injected control group. Threonine (thr) and methionine (met) injected eggs had higher chick weight and chick to egg weight ratio and met and arg injected chicks had higher fourth and seventh week body weight than un–injected control chicks. No significant difference was recorded for FCR of in ovo amino acids injected birds. Met and glycine (gly) injected chicks had higher bursa weight, whereas, those injected with met thr, gly and isoleucine (ile) had higher spleen weight on the day of hatch. Humoral immune response (SRBC titre) was higher in most of the amino acid injected chicks except lys group. Cell mediated immunity (response to PHAP mitogen) was higher in lys, arg, gly and ile injected chicks. The chicks injected with amino acids invariably had higher plasma protein and lower plasma glucose on the day of hatch. It may be concluded that met and thr were critical for the growth of chicken embryo, however, during post–hatch period met and arg played major role. In ovo injected amino acids can also act as immunomodulator but their role in gastrointestinal development needs further research.