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1
Strydom, P. E., R. T. Naudé, M. F. Smith, M. M. Scholtz e J. B. van Wyk. "Characterization of indigenous African cattle breeds in relation to carcass characteristics". Animal Science 70, n. 2 (aprile 2000): 241–52. http://dx.doi.org/10.1017/s1357729800054709.
Testo completoAbstract (sommario):
AbstractCarcass traits of two indigenous African (Sanga) breeds (Afrikaner and Nguni), one indigenous African composite breed (Bonsmara), one foreign composite breed (Santa Gertrudis) and two continental European breeds (Brown Swiss and Pinzgauer) were compared. Treatment means were adjusted to the mean overall subcutaneous fat proportion (47 g/kg). Despite differences in maturity type, only the Afrikaner dressed out significantly (P < 0·05) lower than the foreign breeds. Both Sanga breeds and the Bonsmara had significantly higher muscle yields than the Santa Gertrudis and Pinzgauer, mainly due to the high intermuscular fat of the latter two breeds. When muscle yield was expressed per unit of bone, the Afrikaner and Bonsmara compared favourably with the larger breeds, due to their low bone and intermuscular fat yield, while the Nguni had a relatively high bone yield. The Santa Gertrudis had the lowest muscle yield due to its high bone and intermuscular fat yields, especially when compared with the smaller Bonsmara composite. Both Sanga breeds had significantly higher (P < 0·05) proportions of total weight, meat and bone (Afrikaner P > 0·05) in the high-priced cuts compared with the other breeds at the same subcutaneous fat level. Despite the statistical significance, differences were small in magnitude and probably of little commercial value. At the same time mean subcutaneous fat proportion, tissue yield and distribution patterns expected of late maturing breeds were observed for smaller indigenous breeds, suggesting that it was specific breed effects rather than maturity type effects, which were evident.
2
Haikukutu, L., T. O. Itenge, L. Bosman, C. Visser e E. van Marle-Köster. "Genetic variability of the major histocompatibility complex (MHC) class II (DRB3) in South African and Namibian beef cattle breeds". Advances in Animal Biosciences 8, s1 (ottobre 2017): s19—s21. http://dx.doi.org/10.1017/s2040470017001625.
Testo completoAbstract (sommario):
The major histocompatibility complex region has been implicated in explaining some of the variation observed in adaptability and tick susceptibility of cattle. The bovine leukocyte antigen region of 192 cattle representing indigenous, composite and exotic breeds used in commercial beef production in Namibia and South Africa was investigated using four microsatellite markers. Ticks counted under the tail were taken as an indicator of tick susceptibility. Tick scores of all but one population was low (11 to 20 ticks), with only the South African Bonsmara population having an average score of 31 to 40 ticks per animal. The observed variation based on four microsatellite markers ranged from 5.5 alleles in Namibian Afrikaner to 7.7 alleles in South African Nguni and Bonsmara cattle. Unbiased heterozygosity values ranged from 0.66 (Namibian Afrikaner) to 0.76 (South African Bonsmara). Structure analyses grouped the five populations into three indistinct clusters with limited genetic variation between the populations.
3
Mphaphathi, M. L., M. M. Seshoka, T. R. Netshirovha, Z. C. Raphalalani, N. Bovula, M. R. Thandavhathu, B. Raito, N. L. Kanuya, A. Maqhashu e T. L. Nedambale. "20 Assessment of Motion and Kinematic Characteristics of Semen from Four Cattle Breeds Using Computer-Aided Sperm Analysis". Reproduction, Fertility and Development 30, n. 1 (2018): 149. http://dx.doi.org/10.1071/rdv30n1ab20.
Testo completoAbstract (sommario):
Subjective semen evaluation using standard optical microscopy is the most common practice. Semen parameters routinely assessed are volume, concentration, progressive motility, and morphology. However, computer-aided sperm analysis (CASA) represents an objective evaluation, sperm assessment that are reproducible and reliable. Such semen parameters have not been evaluated in Afrikaner, Brahman, and Bonsmara bulls’ semen. The present study evaluated the sperm motion and kinematics characteristics of semen from stud Afrikaner, Brahman, Bonsmara, and Nguni bulls using CASA technology. The electro-ejaculator was used for semen collection from Afrikaner (n = 11), Brahman (n = 7), Bonsmara (n = 10) and Nguni (n = 16) bulls of known and proven fertility. Semen was collected following 4 days of resting period. The bulls ranged between 5 and 6 years of age. After collection, the semen samples were immediately transferred to a thermo-flask and maintained at 37°C for further evaluation in the mobile laboratory (Nedambale, 2014). The CASA-Sperm Class Analyzer® system (Microptic, Barcelona, Spain) was used to evaluate sperm motion, velocity, and kinematic parameters or characteristics of raw/fresh semen from 4 cattle breeds. Data were analysed using GenStat® statistical programme (VSN International, Hemel Hempstead, United Kingdom). Treatment means were compared using one-way ANOVA. The total sperm motility rate was similar for all breeds: Afrikaner (92.2 ± 4.2), Brahman (90.7 ± 9.0), Bonsmara (93.9 ± 4.0), and Nguni (96.0 ± 2.7). However, Brahman and Afrikaner bull semen had higher sperm cells moving in a progressive motility of 57.3 and 45.6%, respectively, compared with other breeds (P < 0.05). Nguni, Afrikaner, and Bonsmara had the highest sperm cells moving in a rapid movement of 73.7, 72.4, and 67.4% (P > 0.05), respectively. The bulls sperm trajectories had a variation, as they were recorded to be irregular and not linear (P < 0.05). The straight-line sperm velocity (µm s−1), wobbling %, and amplitude of lateral head displacement % was similar for the 4 breeds (P > 0.05). In conclusion, CASA technology was a useful technique for assessing differences in sperm motion and kinematic (motility and velocity characteristics) among different bull breeds.
4
Maré, Frikkie Alberts. "The Water–Economy Nexus of Beef Produced from Different Cattle Breeds". Water 13, n. 18 (14 settembre 2021): 2513. http://dx.doi.org/10.3390/w13182513.
Testo completoAbstract (sommario):
The sustainable use of water, or any other natural resource for that matter, is not the only factor that should be considered in terms of sustainability, as social equity and economic prosperity are equally important. The objective of this study was to analyse different breeds of beef cattle, following the same production method, in terms of their water footprint and economic value addition for different links in the value chain. A bottom-up approach was applied to identify the breed with the best economic water consumption in terms of beef production. The results indicated that the total WF/kg carcass revealed notable differences between the various breeds. The Bonsmara had the smallest WF/kg carcass, while the Limousin had the largest. The WF/kg of beef for the different cuts (rib eye, topside, and flank) showed large variations between the breeds and between the different cuts of beef from the same breed. In terms of the economic water consumption, the Angus consumed between 4% and 25% less water per rand of economic value addition than the Bonsmara, Simmentaler, Simbra, Limousin, Afrikaner, and Brahman. When the economic water consumption of the individual value links was considered, it was found that Bonsmara had the best figures for cow–calf production, while the Limousin and Simmentaler were the best in terms of feedlot finishing and processing, respectively. These contradicting results showed the importance of a bottom-up approach to ensure that the fallacy of division does not occur and, secondly, that possible problem areas in the value chain are identified and addressed separately.
5
Corbet, N. J., R. K. Shepherd, H. M. Burrow, J. van der Westhuizen, P. E. Strydom e D. J. Bosman. "Evaluation of Bonsmara and Belmont Red cattle breeds in South Africa. 1. Productive performance". Australian Journal of Experimental Agriculture 46, n. 2 (2006): 199. http://dx.doi.org/10.1071/ea05223.
Testo completoAbstract (sommario):
The productive performance of progeny by Bonsmara and Belmont Red sires was compared in contemporarily reared groups in South Africa. Measurements on 4279 pedigreed progeny of 96 Bonsmara sires and 18 Belmont Red sires were recorded over 15 years in 4 diverse climatic regions of South Africa. Growth traits were measured on growing stock from birth to 18 months at pasture. Weight gain, feed conversion rate, frame size, scrotal circumference and visually assessed ‘functional efficiency’ scores were recorded on male progeny fed high protein rations. Carcass traits were measured on a subset of the male progeny. Age at first calving, and repeated measurements of calving date and calving interval were recorded on breeding females as indicators of reproductive performance. Tick counts were made on males and females across a range of ages during times of heavy field infestation. There were differences in progeny performance for some traits. Bonsmara sired animals generally scored higher than Belmont Red progeny for functional efficiency. Belmont Red sired calves were lighter at birth (35.9 v. 37.3; P0.05) and cows by Belmont Red sires had a shorter average calving interval (440 v. 455; P<0.05). Sire breed by region interaction was not important. The differences in scored and measured traits generally reflected differences in selection policies adopted by the breed societies. Variation in growth and fertility traits due to sire was greater than variation due to breed and demonstrated the potential for identifying superior individuals. The performance of the sire breeds for the range of traits and environments studied advocated that selected Bonsmara and Belmont Red animals from South African herds would be suitable for inclusion in breeding programs in Australian Belmont Red herds.
6
Bó, G. A., I. Anduaga, B. Bernal, G. Moreira, A. Cedeño, J. Barajas, M. Pelizzari, S. Andrada e A. Tribulo. "176 SERUM ANTIMULLERIAN HORMONE CONCENTRATIONS AND IN VITRO EMBRYO PRODUCTION IN BEEF CATTLE". Reproduction, Fertility and Development 28, n. 2 (2016): 219. http://dx.doi.org/10.1071/rdv28n2ab176.
Testo completoAbstract (sommario):
The collection of high numbers of oocytes for in vitro embryo production in the cow depends on the number of antral follicles available for aspirations. The number of antral follicles varies significantly among cows and can be estimated by ovarian ultrasonography or measurement of serum concentrations of antimullerian hormone (AMH). The AMH is secreted by the granulosa cells of small antral follicles and serum concentrations are independent of the stage of the oestrous cycle. Therefore, it may be useful as a tool to select oocyte donors for in vitro embryo production. An experiment was designed to evaluate the effect of breed of cattle and the correlation of serum AMH concentrations on the number of viable oocytes and embryos produced in vitro. Cumulus-oocyte complex were collected during 44 ultrasound-guided follicle aspiration sessions performed at random stages of the oestrous cycle without superstimulation in 14 Bonsmara, 11 Braford, and 19 Brangus cows that were used for commercial in vitro embryo production using frozen-thawed semen from bulls of the same breed. Blood samples were collected by jugular venipuncture at the time of OPU, centrifuged at 3000 × g for 30 min for serum separation which was frozen at –20°C until AMH analysis. Serum AMH was evaluated using an ELISA (AnshLabs, Webster, TX, USA). The sensitivity of the AMH assay was 0.011 ng mL–1 and intra-assay CV were <5%. The number of viable oocytes collected and embryos produced in each breed were compared by ANOVA and means were compared by the protected l.s.d. test when ANOVA revealed statistically significant differences. Regression analysis and Pearson correlation were used to determine the relationship between the number of viable oocytes aspirated and the number of embryos produced. The mean (± SEM) number of viable oocytes collected was greater (P < 0.05) from Brangus (23.3 ± 4.3) and Braford (22.5 ± 3.6) than from Bonsmara donors (12.2 ± 2.5). Although not statistically different, the numbers of embryos produced followed the same pattern (Brangus, 4.4 ± 0.9; Braford, 3.4 ± 0.6; Bonsmara, 2.9 ± 0.5). Serum AMH concentration was positively correlated with the number of viable oocytes collected in all breeds (R2 = 0.63 for Bonsmara, 0.50 for Braford, 0.32 for Brangus; P < 0.01). Serum AMH concentrations were also correlated with the number of embryos produced in all breeds (R2 = 0.32 for Bonsmara, 0.16 for Braford, 0.39 for Brangus). However, AMH concentrations were not significantly correlated with the proportion of viable oocytes collected and embryos produced. Results demonstrate a breed effect on the number of oocytes collected per session and that circulating AMH concentrations are correlated with the number of viable oocytes collected per session in commercial in vitro embryo production programs.
7
Mamogobo, M. D., N. O. Mapholi, K. A. Nephawe, T. L. Nedambale, T. J. Mpofu, Y. P. Sanarana e B. J. Mtileni. "Genetic characterisation of non-descript cattle populations in communal areas of South Africa". Animal Production Science 61, n. 1 (2021): 84. http://dx.doi.org/10.1071/an20030.
Testo completoAbstract (sommario):
Context Indigenous cattle breeds represent an important genetic resource for livelihood of communal-area inhabitants. Indigenous breeds have the ability to withstand harsh climatic conditions, can adapt genetically to poor-quality forages and are resistant to parasites and diseases. These unique traits possessed by indigenous breeds are under threat because of unrestrained crossing with exotic commercial breeds, and this can lead to total loss of a breed. Aims The study was conducted to assess the genetic diversity and population structure of South African non-descript communal beef cattle populations by using 25 microsatellite markers. Methods Unrelated and non-descript animals (n = 150) were sampled from communal areas from five (5) provinces of South Africa, namely, Eastern Cape, KwaZulu–Natal, Limpopo, Mpumalanga and the North West, with 30 samples per breed taken. Six (6) known cattle breeds (n = 180) were used as a reference population. This included Angus, Afrikaner, Bonsmara, Brahman, Drakensberger and the Nguni, with 30 samples per breed. Key results High level of genetic diversity was found across the five non-descript populations, with an average heterozygosity of 75%. The Limpopo population was found to be the most diverse population, with the highest average number of alleles (8.5) and heterozygosity (ranging between observed heterozygosity of 70% and expected heterozygosity of 79%). STRUCTURE software assigned populations (2 ≤ K ≤ 20), with the most probable cluster being at K = 7. The Eastern Cape, KwaZulu–Natal and Limpopo populations had genetic material similar to those possessed by the Nguni and Bonsmara reference populations. Conclusions Results from the study showed that most genetic differentiation occurred within populations rather than among populations, and this might be due to the fact that there is no selection for or against any specific production trait expressed in the populations. Implications The obtained information will serve as a baseline for the development and implementation of sound breeding programs that will assist in controlling the gene flow, so as to lower the possible genetic dilution of the currently available genetic material.
8
Grobler, SM, MM Scholtz, H. Van Rooyan, M. Mpayipheli e FWC Neser. "Methane production in different breeds, grazing different pastures or fed a total mixed ration, as measured by a Laser Methane Detector". South African Journal of Animal Science 44, n. 5 (19 gennaio 2015): 12–16. http://dx.doi.org/10.4314/sajas.v44i5.3.
Testo completoAbstract (sommario):
Agriculture is responsible for 5% to 10% of the global anthropogenic greenhouse gas (GHG) emissions. Livestock contribute about 65% of agricultural GHG and enteric fermentation accounts for 90% of this. The global warming potential of CH4 is known to be 23 times more than that of carbon dioxide, resulting in it being a significant role player in the greenhouse gas family. The laser methane detector (LMD) is an instrument that has the potential to measure enteric CH4 emission from livestock under normal husbandry activities. This study was aimed at evaluating the efficiency and results, when using the LMD to measure CH4 production under normal production conditions. Twelve heifers, four each from the Bonsmara, Nguni and Jersey breeds, were subjected to grazing natural veld, forage sorghum under irrigation, oats pasture under irrigation or a total mixed ration. Measurements were taken late afternoon (18:00) when the animals were ruminating. Four repeated measurements, lasting 60 seconds each, were taken on 10 consecutive days on each of the production systems. The animals were adapted for a period of 14 days on the specific feed, before the measurements were taken. The Jersey heifers produced significantly less CH4 than the Bonsmara and Nguni on natural veld, with no significant differences between breeds on the forage sorghum. On natural veld the heifers generated 48% more CH4. These results thus indicate that the LMD produce sensible and repeatable measurements that can be interpreted in respect of CH4 production by cattle. The next step will be to increase the number of breeds, numbers per breed, and feeding strategies over all seasons in order to validate and build up a baseline data set on the use of the LMD to measure CH4 emissions from cattle under different grazing conditions.Keywords: Heifers, methane emission, pastures, total mixed ration
9
Corbet, N. J., R. K. Shepherd, H. M. Burrow, K. C. Prayaga, J. van der Westhuizen e D. J. Bosman. "Evaluation of Bonsmara and Belmont Red cattle breeds in South Africa. 2. Genetic parameters for growth and fertility". Australian Journal of Experimental Agriculture 46, n. 2 (2006): 213. http://dx.doi.org/10.1071/ea05224.
Testo completoAbstract (sommario):
Genetic parameters were estimated for growth and fertility indicator traits in a South African beef cattle population. Measurements on 5601 pedigreed progeny of 96 Bonsmara sires, 18 Belmont Red sires and 20 Bonsmara × Belmont Red cross sires were recorded over 19 years in 4 diverse climatic regions of South Africa. Growth traits were measured on growing stock from birth to 18 months at pasture. Cow weights were measured at calving and weaning. Age at first calving, and repeated measurements of calving day and calving interval were recorded on 1993 breeding females as indicators of reproductive performance. The traits were analysed using univariate and bivariate animal models with maternal effects fitted. Direct heritability of growth traits (0.11–0.42) and female fertility traits (0.02–0.13) suggested that genetic progress could be made by selection for some traits. Genetic correlations between growth and fertility traits were variable (–0.47–0.85) and indicated that multi-trait selection would be the best method of dealing with multidirectional forces on productivity traits. Genetic correlations between direct and maternal effects on liveweight traits were mostly negative indicating that genetic improvement of traits with strong maternal influence, such as weaning weight, would be complicated and supported the use of post-weaning weights with less maternal influence as selection criteria to improve the direct additive component of growth. The genetic parameter estimates provide useful reference values for estimation of breeding values in a proposed combined-breed genetic evaluation program.
10
Grobler, R., C. Visser, A. Capitan e E. van Marle-Köster. "Validation of the POLLED Celtic variant in South African Bonsmara and Drakensberger beef cattle breeds". Livestock Science 217 (novembre 2018): 136–39. http://dx.doi.org/10.1016/j.livsci.2018.10.003.
Testo completo
11
Pyoos, G. M., M. M. Scholtz, M. D. MacNeil, A. Theunissen e F. W. C. Neser. "Genetic effects from an Afrikaner, Bonsmara, and Nguni three-breed diallel and top-crosses of Angus and Simmental sires". South African Journal of Animal Science 50, n. 3 (26 agosto 2020): 366–77. http://dx.doi.org/10.4314/sajas.v50i3.3.
Testo completoAbstract (sommario):
Individual and maternal breed additive effects and heterosis exist for most economically important traits in cattle. Crossbreeding may therefore be valuable for emerging and commercial beef farmers in improving the productivity of their herds. Calves were produced by mating Afrikaner, Bonsmara and Nguni cows to Afrikaner, Bonsmara, Nguni, Angus and Simmental bulls. The cows used were from Vaalharts Research Station or were purchased from other herds. Data were collected over three years. Individual and maternal additive effects and individual heterosis were estimated simultaneously as continuous linear variates. The estimated genetic effects were then used to predict production levels that may be achieved through implementation of top-cross, two-breed rotation, and terminal sire crossbreeding systems. The individual estimates of the genetic effects were relatively small and in most cases were not different from zero, with the exception of the maternal additive effects of Nguni on preweaning traits and their individual additive effect on cow weight, which were less than those of Bonsmara. However, the alternative crossbreeding systems differed across traits. The straight-bred breeding system was least efficient, followed by the crisscross system (+2%) and the terminal sire system that utilized Simmental (+4%), with the terminal sire system utilizing Angus being on average most efficient (+8%). The inter-generational genetic differences in cow weight that resulted from the use of different breeds of sire increased its standard deviation by 5 to 6% in rotational crossing. Despite the relatively small magnitude of the genetic effects, advantages of crossbreeding systems became evident.Keywords: breed additive, crossbreeding, heterosis, post-weaning, pre-weaning
12
Strydom, P. E., L. Frylinck, J. van der Westhuizen e H. M. Burrow. "Growth performance, feed efficiency and carcass and meat quality of tropically adapted breed types from different farming systems in South Africa". Australian Journal of Experimental Agriculture 48, n. 5 (2008): 599. http://dx.doi.org/10.1071/ea06057.
Testo completoAbstract (sommario):
Two experiments measured the ability of tropically adapted beef breeds from resource-poor farmer herds in South Africa to produce high quality beef under commercial feedlot conditions. The resource-poor farming sector consists of ‘emerging’ and communal farmers. The herd and breed groups consisted of Sanga types (tropically adapted Bos taurus breed) including Nguni, Tuli, Bonsmara and Drakensberger, as well as Brahman and non-descript groups. The cattle were slaughtered after an average of 97 days in the first experiment and after an average of 92, 140 and 169 days on a grain-based diet in the second experiment. Growth performance, carcass quality and yield, occurrence of disease and meat quality were measured. The performance of the breeds groups was a function of their genetic potential and herd type (carcass weight and condition at arrival). Steers from emerging and communal farmer herds enter the feedlot at a lighter weight, but show similar growth performance to achieve acceptable, albeit lighter carcass weights, than their commercial counterparts. The incidence of disease was no different between commercial, emerging and communal herds. Carcass and meat quality analyses indicate small or no differences between herd types or breeds, except that Brahman produced tougher meat. It was concluded that cattle from resource-poor farmer herds have the ability to meet the specifications of South Africa’s commercial beef markets, indicating a genuine opportunity for import substitution, whereby the more than 5 million cattle in resource-poor farmer herds could be used to overcome the significant shortfall in South Africa’s domestic beef market demand.
13
Harrison, Blair E., Rowan J. Bunch, Russell McCulloch, Paul Williams, Warren Sim, Nick J. Corbet e William Barendse. "The structure of a cattle stud determined using a medium density single nucleotide polymorphism array". Animal Production Science 52, n. 10 (2012): 890. http://dx.doi.org/10.1071/an11267.
Testo completoAbstract (sommario):
Genetic progress depends on accurate knowledge of the genetic composition of a population or herd including level of inbreeding and parentage. However, in many circumstances, such as at an individual property level, the relationships between animals may be unknown, or at best, only partly known. In this study, we used DNA from 938 animals and genotypes from ~54 000 single nucleotide polymorphisms (SNP) to determine the genetic structure of a stud from Central Queensland. Animals on the study were bred using multi-sire mating in mobs of composite tropically adapted cattle of the Senepol, Belmont and Bonsmara breeds. Following genotyping using an array of 54 000 SNP, we were able to separate animals into breed groups using principal components and show that ~400 SNP were sufficient to separate animals into stable groups if the sample was genetically diverse. However, precise principal component values were only achieved when a few thousand SNP were used. We characterised the pedigree relationships between individuals using a genome relationship matrix. At least 3000 SNP were required to calculate accurate relationship coefficients between individuals. Around 19% of paired comparisons between animals showed similarity equivalent to sharing a great-grandparent or 1/64 shared ancestry. Approximately 8% of the individuals showed more than 10% inbreeding. To demonstrate the utility of calculating the relationship coefficients, we counted the tick burden on each animal at more than one time and then calculated the heritability of tick burden of h2 = 0.46 (±0.08). There was no significant genetic difference in tick burden between Belmont and Bonsmara cattle compared with Senepol on this property once a genetic relationship matrix was included to account for co-ancestry of individuals.
14
Mohleko, Helen Mapeka, Mpho Pilane Cyril, Treadwell Robert, Ng’ambi Jones e Banga Cuthbert. "Comparison of embryo developmental rates in Nguni, Bonsmara and Boran beef cattle breeds following in vitro fertilization and artificial insemination". African Journal of Biotechnology 18, n. 30 (31 ottobre 2019): 962–69. http://dx.doi.org/10.5897/ajb2019.16947.
Testo completo
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Falowo, Andrew Bamidele, Voster Muchenje e Arno Hugo. "Effect of sous-vide technique on fatty acid and mineral compositions of beef and liver from Bonsmara and non-descript cattle". Annals of Animal Science 17, n. 2 (1 maggio 2017): 565–80. http://dx.doi.org/10.1515/aoas-2016-0078.
Testo completoAbstract (sommario):
Abstract This study examined the fatty acid and mineral compositions of raw and cooked beef and liver from Bonsmara (BD) and non-descript (ND) cattle, raised on natural pasture. Samples were collected from 80 cows and thermal-processed at 65°C for 120 minutes and 85°C for 60 minutes using sous-vide techniques, and then analysed for fatty acid and mineral compositions. The results did not show differences in individual fatty acid composition of meat samples between the breed (P>0.05). However, the raw beef sample had higher content of monounsaturated fatty acids (MUFA , 40.22% ± 3.79 ND, 42.53% ± 2.39 BD) and lower content of polyunsaturated fatty acids (PUFA , 11.02% ± 5.47 ND, 10.13% ± 6.73 BD) than liver (MUFA , 20.11% ± 4.76 ND, 21.08% ± 2.46 BD; PUFA , 30.73% ± 5.20 ND, 31.11% ± 2.37 BD) (P<0.05). The PUFA /MUFA and n-6/n-3 ratios, atherogenicity and desaturase indices were comparable between breeds, but higher in beef than liver. The total percentage of saturated fatty acid, MUFA and PUFA retained after cooking were numerically higher in liver than in beef (P>0.05). The results further revealed higher contents of Na, Mg, and Zn in raw beef than liver. However, the content of Na, Mg, and Zn in the beef and liver were not significantly (P>0.05) affected after cooking. Based on the PUFA proportion of the total lipids in beef (11.02%) and liver (31.11%) and n-6/n-3 PUFA ratio in beef (2.54) and liver (1.34), consumption of liver and beef from cattle raised on pasture could be beneficial to human health. Additionally, application of sous-vide technique can be used to minimize the nutritional losses in beef and liver.
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Bernal, B., J. Revol, J. M. Oviedo, A. Tribulo, H. Tribulo, G. Moreria e G. A. Bó. "246 INFLUENCE OF BREED AND SEASON ON IN VITRO EMBRYO PRODUCTION". Reproduction, Fertility and Development 28, n. 2 (2016): 255. http://dx.doi.org/10.1071/rdv28n2ab246.
Testo completoAbstract (sommario):
A retrospective analysis of in vitro production (IVP) data was done to determine the influence of breed and season on the production of viable oocytes and embryos. Cumulus‐oocyte complexes (COC) were obtained from 1946 ultrasound-guided follicle aspiration (ovum pickup) sessions performed at random stages of the oestrous cycle without superstimulation in Bos taurus and Bos indicus donors in commercial IVP in Argentina. Frozen-thawed conventional semen was used in beef cattle and conventional (n = 139) and sexed-selected (n = 481) semen in dairy cattle. The COC were classified, matured in B-199 medium, fertilized in IVF-SOF medium (Day 0), and cultured in SOF medium supplemented with 0.4% BSA under oil at 38.8°C, 5.5% CO2, and saturated humidity for 7 days. The number of viable COC and transferable embryos in each breed and season were compared by ANOVA and means were compared by Fisher’s Least Significant Difference test. Proportions were first transformed by arcsin and then analysed by ANOVA. To simplify the interpretation of the results, breeds were grouped as follows: dairy Bos taurus (Holstein, n = 620), beef Bos taurus (Angus and Bonsmara, n = 229), Bos taurus × Bos indicus (Brangus and Braford, n = 1045), and Bos indicus (Brahman, n = 52). There was no interaction between breed and season for any of the end points analysed (P > 0.1). Mean (± standard error of the mean) numbers of viable COC and transferable embryos were higher (P < 0.01) in Bos indicus × Bos taurus (19.3 ± 0.4 and 5.3 ± 0.2, respectively) and Bos indicus (15.8 ± 1.4 and 6.8 ± 0.9, respectively) than in beef (11.6 ± 0.5 and 3.0 ± 0.2, respectively) and dairy (8.0 ± 0.2 and 1.6 ± 0.1, respectively) Bos taurus donors. Cleavage rates were higher (P < 0.01) in Bos indicus (72%) than in the other breeds (57% for Bos indicus × Bos taurus and dairy Bos taurus and 54% for beef). Transferable embryo rates were higher (P < 0.01) in Bos indicus (41%) and Bos indicus × Bos taurus (30%) than in beef Bos taurus (26%). Dairy Bos taurus had the lowest (P < 0.01) embryo rates of all breeds (21%). In dairy Bos taurus, cleavage rates, the number of embryos produced, and transferable embryo production rates were higher (P < 0.01) when conventional semen was used (62%, 2.8 ± 0.15, and 27%, respectively) compared to sexed-selected semen (55%, 1.3 ± 0.1, and 19%, respectively). With regards to season, the number of viable COC was highest (P < 0.01) in the spring (14.3 ± 0.5), lowest in the summer (11.3 ± 1.0), and intermediate in the fall (12.2 ± 1.2) and winter (13.7 ± 1.2), which did not differ. Although not affected significantly by season, the number of embryos produced was numerically lower in the summer (2.8 ± 0.4) than in the spring (4.2 ± 0.2), winter (4.5 ± 0.5), or fall (4.6 ± 0.5). In conclusion, in vitro embryo production was directly influenced by breed and season. Bos indicus influenced cattle and the spring season were preferable for commercial IVP programs that did not include superstimulation.
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Nyangiwe, Nkululeko, Sindisile Goni, Louis P. Hervé-Claude, Inga Ruddat e Ivan G. Horak. "Ticks on pastures and on two breeds of cattle in the Eastern Cape province, South Africa". Onderstepoort J Vet Res 78, n. 1 (24 febbraio 2011). http://dx.doi.org/10.4102/ojvr.v78i1.320.
Testo completoAbstract (sommario):
Many studies on the population dynamics of questing ticks on pastures and of parasitic ticks on cattle have been conducted. Few, however, have attempted to link the two in a single study. This study aimed to assess the population dynamics of questing ixodid ticks on pastures and of adult ticks on two breeds of cattle with different levels of susceptibility to tick infestation on the same pastures. Between January 2005 and December 2009 questing ixodid ticks were collected monthly from natural pastures at the Döhne Agricultural Development Institute and at the adjacent Campagna Production System in the Amahlathi District, Eastern Cape province, South Africa. Between February 2007 and January 2010 adult ticks were collected monthly from Bonsmara and Nguni cattle grazing these pastures. Ten tick species were collected from the pastures and 12 from the cattle. Significantly more questing larvae of Rhipicephalus appendiculatus, Rhipicephalus decoloratus, Rhipicephalus evertsi evertsi and Rhipicephalus microplus were recovered from the pastures grazed by Bonsmara cattle than from those grazed by Nguni cattle (p ≤ 0.05). Significantly more adult Hyalomma rufipes, Rhipicephalus follis, R. appendiculatus, R. decoloratus, R. evertsi evertsi and R. microplus were collected from the Bonsmara cattle than from the Nguni cattle (p ≤ 0.05). The study showed that Nguni cattle are less susceptible to tick infestation than are Bonsmara cattle and fewer questing ticks are collected from pastures grazed by Nguni cattle than by Bonsmara cattle.
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Jiyana, S. T., M. M. Ratsaka, K.-J. Leeuw e K. R. Mbatha. "Effects of dietary fibre level on rumen pH, total microbial count and methanogenic archaea in Bonsmara and Nguni steers". South African Journal of Animal Science 51, n. 1 (29 marzo 2021). http://dx.doi.org/10.4314/sajas.v51i1.8.
Testo completoAbstract (sommario):
A study was conducted to evaluate the effect of the level of dietary fibre on rumen pH, total microbial count and methanogenic archaeacount of Bonsmara (225 ± 10.0 kg live weight) and Nguni (215 ± 10.0 kg live weight) steers. Nine steers per breed were used, aged 8 to 9 months. A 3 x 2 factorial experiment was executed with treatments allocated in a completely randomized design. The treatments were diets which included 64.3% neutral detergent fibre (NDF) for diet 1, 40.4% NDF for diet 2, and 29.9% NDF for diet 3. Steers were fed for 90 days and housed in individual pens. Rumen fluid was collected from steers using a stomach tube. Rumen fluid samples were taken immediately to the laboratory for microbial assay. Data were subjected to analysis of variance (ANOVA). The various levels of dietary fibre did not affect rumen pH and methanogenic archaea count. However, a low-fibre diet yielded high rumen total microbial count for Bonsmara steers and low rumen total microbial count for Nguni steers. Therefore, a low-fibre diet can be applied as a viable strategy to enhance rumen total microbial count in exotic beef breeds and crossbred cattle such as Bonsmara. Nguni steers fed a high NDF diet had higher rumen total microbial count than Nguni steers fed a low-fibre diet. Therefore, a high NDF diet can be used efficiently by feeding it to indigenous breeds and purebred cattle such as Nguni.
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Malusi, N., A. B. Falowo e E. M. Idamokoro. "Herd dynamics, production and marketing constraints in the commercialization of cattle across Nguni Cattle Project beneficiaries in Eastern Cape, South Africa". Pastoralism 11, n. 1 (27 gennaio 2021). http://dx.doi.org/10.1186/s13570-020-00186-x.
Testo completoAbstract (sommario):
AbstractThis paper examines the challenges restricting the commercialization of cattle across Nguni Cattle Project beneficiaries in South Africa. Data were collected from one hundred and twenty (120) Nguni cattle beneficiaries using a structured questionnaire across six district municipalities of the Eastern Cape Province. Results revealed that majority of Nguni cattle beneficiaries were males, were above 60 years old, and have received formal training in livestock farming. Most of the beneficiaries reared cattle with other livestock species, with 45% owned non-descript breeds, 33% Nguni and 22% other breeds such as Bonsmara and Brahman. About 79.2% of the beneficiaries practised continuous grazing while 52.5% give their cattle supplements, with most commonly (48%) using rivers as the source of water. Most beneficiaries (38.4%) reported diseases as main production constraints, followed by stock theft (27.5%) and feed shortages (22.5%). Furthermore, results showed that 80.8% of beneficiaries market one to 10 cattle per year, 64.8% adult cattle (2+ years old) and 35.2% weaners (8 months to 1 year). Most beneficiaries (78.7%) used private marketing channels to sell their animals, while 4.3% used abattoirs. Factors identified as the main market constraints included low cattle numbers (41.7%), inability to meet formal market standards (25%) and inadequate government support. There was a strong association between formal livestock training and cattle marketing attributes as well as production constraints. In conclusion, more emphasis should be given to improve cattle production and commercialization through provision of more cattle, livestock trainings and market services to communal farmers.
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Collins-Lusweti, E. "The performance of the Nguni, Afrikander and Bonsmara cattle breeds in developing areas of Southern Africa". South African Journal of Animal Science 30, n. 4 (1 gennaio 2000). http://dx.doi.org/10.4314/sajas.v30i4.3895.
Testo completo
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Tsotetsi, A. M., e P. A. Mbati. "Parasitic helminths of veterinary importance in cattle, sheep and goats on communal farms in the northeastern Free State, South Africa". Journal of the South African Veterinary Association 74, n. 2 (27 giugno 2003). http://dx.doi.org/10.4102/jsava.v74i2.503.
Testo completoAbstract (sommario):
The purpose of the study was to record and determine intensities, seasonal incidence and distribution of helminth parasites of veterinary importance that occur in cattle, sheep and goats in the northeastern Free State. The study was conducted at Harrismith and Kestell and in Qwa-Qwa from March 2000 to May 2001. Cattle of various breeds (including Bonsmara, Simmentaler and Friesian), Merino sheep and Angora goats were sampled. Faecal samples were analysed using the McMaster and Visser sieve techniques for egg counts and faecal cultures for 3rd-stage nematode larvae identification. Haemonchus and Oesophagostomum were the dominant nematode genera found to be infecting the animals. The socioeconomic status of the farmers in the study area was determined through a questionnaire survey aimed at recording their management strategies. It indicated that 81 % of farmers take care of their livestock by feeding them with supplements. The low to moderate faecal egg counts from cattle showed that helminth infections in this region are still under control even though helminthosis seems to be a problem in small-stock, since EPG counts of more than >1000 were found. Cattle farmers in this region are encouraged to continue with good animal husbandry practices that have ensured that helminth infections rates are kept low. Small-stock farmers are, however, encouraged to control helminth infections in their sheep and goats by anthelmintic treatment.