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Strydom, P. E., R. T. Naudé, M. F. Smith, M. M. Scholtz, and J. B. van Wyk. "Characterization of indigenous African cattle breeds in relation to carcass characteristics." Animal Science 70, no. 2 (April 2000): 241–52. http://dx.doi.org/10.1017/s1357729800054709.
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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.
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Uza, D. V. "THE REPRODUCTIVE PERFORMANCE OF SANTA GERTRUDIS BEEF CATTLE IMPORTED INTO NIGERIA." Nigerian Journal of Animal Production 13 (January 16, 2021): 81–87. http://dx.doi.org/10.51791/njap.v13i.2392.
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An analysis of some reproductive performance traits was carried out for the period 1983 to 1985, in a herd of 168 Santa Gertrudis beef cattle imported from Oklahoma, U.S.A. in 1981 into lkyogen cattle ranch in Nigeria. Three calf crops were obtained during the period. Mean pregnancy rate and calving percentage were 63.24 and 55.72% respectively; with pregnancy rate increasing from 54.23 to 70,41% while calving percentage increased from 48.42 to 61.11% during the period. Mean calf mortality rate of 40.83% was high and increased from 36.34 to 45.15%. Mean adult mortality rate was 5.68% of which 16.99% was recorded in the first year of introduction but this declined sharply to 0O2% in the next two years. Mean weaning rate was 50.08% and this declined from 55.71 to 44.32% during the period under study. Mean birth weight, weaning weight and calving interval were 27.8 t 0.29 kg, 174 ± 4.6kg and 451 days respectively It was concluded that with the exception of weaning weight, the reproductive traits of the imported Santta Gertrudis cattle reported in this study were not superior to those of the predominant indigenous cattle breeds of Nigeria. The implications of these results in the beef cattle industry of Nigeria are discussed.
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Marestone, Bruna Silva, Carolina Amália Souza Dantas Muniz, Edson Luis de Azambuja Ribeiro, and Sandra Maria Simonelli. "Environmental effects on pre-weaning traits in Santa Gertrudis cattle." Semina: Ciências Agrárias 40, no. 3 (May 21, 2019): 1297. http://dx.doi.org/10.5433/1679-0359.2019v40n3p1297.
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We aimed to evaluate environmental effects on pre-weaning traits of Santa Gertrudis cattle. We used 213 standardized records for adjusted 205-day weight at weaning (W205), average daily gain from birth to weaning (AGD), and number of days to gain 160 kg from birth to weaning (D160), obtained from the Santa Gertrudis Breeders' Association for animals born between 1990 and 1997. The files were edited with information regarding cow age at calving (CAC) and contemporary group (CG), for which the effects of year and season of birth, animal category, herd, and sex were considered. It was observed that cow age at calving, which had linear and quadratic effects, and effect of contemporary group were significant (P < 0.0001) for the evaluated traits. Estimated averages were 198.05 ± 40.64 kg, 0.790 ± 0.198 kg day-1, and 288.05 ± 67.18 days for W205, ADG, and D160, respectively. Males were 4.67 kg heavier (197.17 kg) than females, on average. Regarding the animal category effect, the classified females were 2.3% heavier than the unclassified, on average. On average, animals born in the dry season were 1.6% lighter than those born in the rainy season (197.18 kg). Thus, environmental effects are important and should be considered in any analysis model.
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Constantinoiu, C. C., A. Lew-Tabor, L. A. Jackson, W. K. Jorgensen, E. K. Piper, D. G. Mayer, L. Johnson, B. Venus, and N. N. Jonsson. "Local immune response to larvae ofRhipicephalus microplusin Santa Gertrudis cattle." Parasite Immunology 40, no. 4 (February 15, 2018): e12515. http://dx.doi.org/10.1111/pim.12515.
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Pivaro, Thiago Martins, Wignez Henrique, Emanuel Almeida Oliveira, José Luiz Viana Coutinho Filho, Roberto Molinari Peres, and Victor Galli Carvalho. "Carcass characteristics of purebred and crossbred Nellore females fed solely pasture." Semina: Ciências Agrárias 37, no. 6 (December 14, 2016): 4213. http://dx.doi.org/10.5433/1679-0359.2016v37n6p4213.
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This research aimed to compare carcasses of purebred and crossbred Nellore females reared uniquely on pasture (Brachiaria decumbens and Brachiaria brizantha cv. Marandu). Breeds assessed consisted of purebred Nellore (16) and Nellore x Santa Gertrudis crossbred (16), being 32 ± 1.5 months old. All animals were slaughtered as they reached 450 kg. Crossbred females showed higher slaughter, hot and cold carcass weights and longer lengths (P < 0.05). Conversely, purebred animals attained greater carcass yields (P < 0.05). Nonetheless, crossbred females had higher primal cut weights and plate/ flank percentage (P < 0.05). Also, non-carcass components as kidneys, liver, kidney-pelvic-heart fat showed higher weights for crossbred females (P < 0.05). Thus, regarding beef cattle reared and finished exclusively on grazing areas, crossbred females (Nellore x Santa Gertrudis) may be the most profitable ones for cattle raisers, since they produce heavier slaughtering carcasses. Notwithstanding, they might be interesting for meat industry, for yielding more in prime cuts than purebreds, even if raised at the same conditions and slaughtered at same age.
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Schutt, K. M., P. F. Arthur, and H. M. Burrow. "Brahman and Brahman crossbred cattle grown on pasture and in feedlots in subtropical and temperate Australia. 3. Feed efficiency and feeding behaviour of feedlot-finished animals." Animal Production Science 49, no. 6 (2009): 452. http://dx.doi.org/10.1071/ea08083.
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The objective of this experiment was to quantify differences in feed efficiency and feeding behaviour of 470 heifers and steers by Brahman, Belmont Red, Santa Gertrudis, Angus, Hereford, Shorthorn, Charolais and Limousin sires mated to Brahman dams. Animals were bred in subtropical Queensland and finished in a temperate New South Wales feedlot. Animals averaged 598 days of age and 425.8 kg at the start of the feed intake test period. Sire breeds did not differ for eating rate, feed conversion ratio or relative growth rate. Generally, higher daily feed intakes (DFI) corresponded with higher average daily gains (ADG). Straightbred Brahmans fed the most frequently (16.6 ± 0.8 sessions/day; P < 0.05) but spent the least time eating of all breeds (67.4 ± 2.7 min/day; P < 0.001). Least squares means for Brahman, Belmont Red, Santa Gertrudis, Angus, Hereford, Shorthorn, Charolais and Limousin sired progeny, respectively, for residual feed intake (RFI; P < 0.05) were 0.02 ± 0.16, 0.14 ± 0.13, –0.10 ± 0.23, 0.54 ± 0.17, –0.27 ± 0.18, 0.29 ± 0.18, –0.46 ± 0.16 and –0.21 ± 0.13 kg/day, and for ADG (P < 0.001) were 1.06 ± 0.05, 1.17 ± 0.04, 1.52 ± 0.08, 1.47 ± 0.06, 1.46 ± 0.06, 1.46 ± 0.06, 1.35 ± 0.06 and 1.38 ± 0.05 kg/day. While straightbred Brahmans did not differ from all other sire breeds for RFI, their lower appetite relative to crossbred contemporaries resulted in the lowest DFI (P < 0.001) and lowest ADG (P < 0.001) overall. Angus sired crosses were the least efficient feeders and spent the most time eating, consumed the most feed and had the highest RFI, but were not significantly different to Santa Gertrudis and Shorthorn crosses for these traits. Angus sired crosses spent 24.1 and 15.4 min/day more time eating (P < 0.001) than straightbred Brahmans and Charolais crosses, and consumed 35 and 13% more feed (P < 0.001) respectively. Charolais sired crosses were the most feed efficient with the lowest RFI and intermediate DFI, and did not differ significantly from the highest ranking sire breeds for ADG or Kleiber ratio. While Belmont Red crosses did not differ from all breeds for RFI, they had significantly lower DFI than British and Santa Gertrudis crosses resulting in lower ADG (P < 0.001) relative to these sire breeds. Therefore, selection of Charolais, Hereford, Limousin and Santa Gertrudis sire breeds would result in the most feed efficient (low RFI) crosses with Brahman without any sacrifice in ADG.
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Aaron, D. K., F. A. Thrift, and N. R. Parish. "Genetic Parameter Estimates for Preweaning Growth Traits in Santa Gertrudis Cattle." Journal of Animal Science 65, no. 6 (December 1, 1987): 1495–99. http://dx.doi.org/10.2527/jas1987.6561495x.
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Kemenes, Paola Augusta, Luciana Correia de Almeida Regitano, Artur Jordão de Magalhães Rosa, Irineu Umberto Packer, Alexander George Razook, Leopoldo Andrade de Figueiredo, Nirlei Aparecida Silva, Maria Antônia L. Etchegaray, and Luiz Lehmann Coutinho. "k-Casein, b-lactoglobulin and growth hormone allele frequencies and genetic distances in Nelore, Gyr, Guzerá, Caracu, Charolais, Canchim and Santa Gertrudis cattle." Genetics and Molecular Biology 22, no. 4 (December 1999): 539–41. http://dx.doi.org/10.1590/s1415-47571999000400012.
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The genotypes for k-casein (<FONT FACE="Symbol">k</FONT>-CN), <FONT FACE="Symbol">b</FONT>-lactoglobulin (<FONT FACE="Symbol">b</FONT>-LG) and growth hormone (GH) were determined by polymerase chain reaction (PCR) and restriction enzyme digestion in seven breeds of cattle (Nelore, Gyr, Guzerá, Caracu, Charolais, Canchim and Santa Gertrudis). <FONT FACE="Symbol">k</FONT>-Casein had two alleles with the A allele occurring at a higher frequency in Bos indicus breeds (0.93, 0.92 and 0.91% for Gyr, Guzerá and Nelore, respectively). The <FONT FACE="Symbol">b</FONT>-lactoglobulin locus had two alleles in all of the breeds. European breeds had a higher frequency of the <FONT FACE="Symbol">b</FONT>-LG A allele than Zebu breeds. The GH locus had two alleles (L and V) in Bos taurus and was monomorphic (L allele only) in all of the Bos indicus breeds evaluated. The highest frequency for the V allele was observed in Charolais cattle. The markers used revealed a considerable similarity among breeds, with two main groups being discernible. One group consisted of Zebu and Santa Gertrudis breeds and the other consisted of European and Canchim breeds.
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Piper, E. K., N. N. Jonsson, C. Gondro, M. E. Vance, A. Lew-Tabor, and L. A. Jackson. "Peripheral cellular and humoral responses to infestation with the cattle tickRhipicephalus microplusin Santa Gertrudis cattle." Parasite Immunology 39, no. 1 (January 2017): e12402. http://dx.doi.org/10.1111/pim.12402.
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Gotti, J. E., L. L. Benyshek, and T. E. Kiser. "Reproductive Performance in Crosses of Angus, Santa Gertrudis and Gelbvieh Beef Cattle." Journal of Animal Science 61, no. 5 (November 1, 1985): 1017–22. http://dx.doi.org/10.2527/jas1985.6151017x.
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Gotti, J. E., and L. L. Benyshek. "Growth Characteristics in Crosses of Angus, Santa Gertrudis and Gelbvieh Beef Cattle." Journal of Animal Science 66, no. 7 (1988): 1585. http://dx.doi.org/10.2527/jas1988.6671585x.
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Khan, R. N., and L. L. Benyshek. "Carcass quality traits among crosses of angus, Santa Gertrudis and Gelbvieh beef cattle." Asian-Australasian Journal of Animal Sciences 6, no. 2 (June 1, 1993): 219–23. http://dx.doi.org/10.5713/ajas.1993.219.
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Khan, R. N., and L. L. Benyshek. "Carcass quality traits in crosses of Angus, Santa Gertrudis and Gelbvieh beef cattle." Asian-Australasian Journal of Animal Sciences 6, no. 2 (June 1, 1993): 225–34. http://dx.doi.org/10.5713/ajas.1993.225.
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Pantoja, Jessica de Carvalho, Aline Pacheco, Jean Kaique Valentim, Cristiane Rebouças Barbosa, Yasmin dos Santos Picanço, Kedson Alessandri Lobo Neves, Tayrine Bianca da Silva Pacheco, and Gustavo da Silva Claudiano. "Avaliação Produtiva e Reprodutiva de Bovinos Santa Gertrudis Sobre Diferentes Condições Alimentares." Ensaios e Ciência C Biológicas Agrárias e da Saúde 25, no. 4 (December 14, 2021): 501–5. http://dx.doi.org/10.17921/1415-6938.2021v25n4p501-505.
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O presente ensaio teve por objetivo avaliar características produtivas e reprodutivas de bovinos da raça Santa Gertrudis em diferentes condições de alimentação. Foram utilizados oito bovinos machos, não castrados, com peso médio de 271 kg e idade média de 15 meses. O experimento teve duração de 98 dias, sendo os animais mantidos em regime de confinamento distribuídos em dois tratamentos, sendo um com dieta de 100% de concentrado e outro com dieta de 70% de concentrado. A pesagem dos animais foi feita quinzenalmente e durante o período foram realizadas duas coletas de sêmen. Foram avaliados aspectos físicos macroscópicos (volume e aspecto) e microscópico (motilidade progressiva, vigor e turbilhonamento) do sêmen. Para as características morfológicas foram avaliados defeitos maiores, defeitos menores e defeitos totais. Para realizar as análises estatísticas dos dados tabulados foi utilizado o software SAS Learning Edition 4.1 ® do SAS Institute. As médias foram comparadas pelo teste SNK ao nível de 5% de probabilidade. Não houve diferença entre as dietas para o peso dos animais. Os bovinos alimentados com restrição de volumoso (T1) consumiram menos, porém apresentaram o mesmo ganho em peso que o grupo com menor restrição (T2). As dietas não influenciaram nas características seminais. Foi encontrada uma porcentagem elevada de defeitos maiores (32,83%) nos parâmetros morfológicos do sêmen. Com os resultados encontrados se pode concluir que a dieta não afetou o peso destes animais e que a maioria ainda estava em fase pré-púbere e inaptos à reprodução, em função de serem animais jovens com características ainda indesejáveis para reprodução. Palavras-chave: Nutrição. Melhoramento Genético. Morfologia Espermática. Abstract The work aimed to evaluate productive and reproductive characteristics of Santa Gertrudis cattle breed at different feeding conditions. Eight male cattle were used, not castrated, average weight of 271 kg and an average age of 15 months. The experiment lasted 98 days, being animals kept in feedlot regime distributed in two treatments, being the (T1) diet with 100% concentrate and (T2) with 70% concentrate diet. The animals weighing was carried out every two weeks and during the period two semen samples were performed. Macroscopic physical aspects were evaluated (volume and aspect) and microscopic (progressive motility, vigor and breaking up) of semen. For the morphological characteristics minor defects, major defects and total defects were assessed . To perform statistical analyses of the data tabulatedSAS Learning Edition 4.1® software (SAS Institute, 2006) was used. The means were compared by SNK. There was no difference between the diets for the animals weight. Cattle fed with bulky constraint (T1) consumed less, but showed the same gain in weight that the group with fewer restrictions (T2). Diets did not influence on seminal characteristics. A high percentage was found of major defects (32.83%) in the semen morphological parameters. With the results it can be concluded that the diet did not affect the weight of these animals and that most were still in prepuberal phase and unfit for breeding, because they are young animals still with undesirable features for reproduction. Keywords: Genetic Improvement. Nutrition. Sperm Morphology.
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Lombard, W. A., F. A. Maré, and H. Jordaan. "The influence of animal traits on feedlot profitability of Santa Gertrudis cattle in South Africa." Agrekon 57, no. 2 (April 3, 2018): 101–7. http://dx.doi.org/10.1080/03031853.2018.1477606.
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Saied, Ahmad A., Laura K. Bryan, and David C. Bolin. "Ulcerative, granulomatous glossitis and enteritis caused by Rhodococcus equi in a heifer." Journal of Veterinary Diagnostic Investigation 31, no. 5 (July 26, 2019): 783–87. http://dx.doi.org/10.1177/1040638719867120.
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Rhodococcus equi infection in horses is common and is characterized by pyogranulomatous pneumonia and ulcerative enterocolitis. R. equi clinical disease in cattle, however, is rare and typically manifests as granulomatous lymphadenitis discovered in the abattoir. A 19-mo-old female Santa Gertrudis had a history of intermittent inappetence and weight loss for a 3-mo period before euthanasia. Gross and histologic examination revealed severe, chronic, ulcerative, and granulomatous inflammation in the tongue, pharynx, and small intestine. Also, the heifer had severe, granulomatous pharyngeal and mesenteric lymphadenitis. Bacterial cultures from the ileum, tongue, and liver yielded numerous-to-moderate numbers of R. equi. PCR analysis of the isolate detected the linear virulence plasmid vapN, which is often identified in bovine isolates ( traA- and vapN-positive). The bacteria also lack the circular plasmids vapA and vapB that are associated with virulence in horses and swine, respectively. We report herein an atypical and unusual clinical presentation of R. equi infection in cattle, which has zoonotic potential.
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Raza, Ali, Peter James, and Ala Tabor. "Proteomics as a Potential Tool for Identifying Biomarkers for Host Resistance to Cattle Tick." Proceedings 36, no. 1 (March 21, 2020): 131. http://dx.doi.org/10.3390/proceedings2019036131.
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The cattle tick, Rhiphicephalus microplus, and the diseases it transmits lead to massive economic losses to cattle industries in tropical and subtropical countries. The emergence of widespread resistance to acaricide drugs and the absence of an effective vaccine for tick control had led to genetic selection of host resistance as a method of choice for non-chemical control of cattle tick. Research to identify host genetic markers associated with tick susceptibility or resistance has been limited to the comparison of local breeds in specific geographic regions. Previous studies have also focused on gene expression profiles, localizing cellular and humoral immune responses, and genome-wide association studies (GWAS) to identify functional genetic variants associated with tick resistance/susceptibility. Given the fact that gene expression results and actual dynamics occurring at the protein level often do not correlate due to post-transcriptional, post-translational and degradation regulation, host proteomics may provide reliable biomarkers to assist in selection to support traditional breeding programs. The present study aims to investigate the variation in protein profiles among tick resistant and susceptible cattle following tick infestation. Preliminary findings suggest that different serum proteins exist between tick resistant and susceptible Santa Gertrudis cattle. This research is supported by Meat & Livestock Australia.
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Barendse, William, Rowan J. Bunch, and Blair E. Harrison. "Variation at CPE but not CEBPA appears to be associated with intramuscular fat deposition in the longissimus muscle of cattle." Animal Production Science 49, no. 7 (2009): 558. http://dx.doi.org/10.1071/ea08307.
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An important step in the localisation of quantitative trait loci is the confirmation of trait-marker associations in independent studies. In this report, we test three single nucleotide polymorphisms (SNP) of two genes for associations to intramuscular fat (IMF) measurements in cattle. We genotyped SNP of carboxypeptidase E (CPE) and ccaat/enhancer binding protein, α (CEBPA) in a sample of a total of 813 cattle of taurine, composite and indicine breeds. All three polymorphisms showed significant differences between breeds, with the widest range found in CEBPA:g.271A > C where the A allele frequency ranged from P = 0.07 in Brahman to 0.88 in Shorthorn. The taurine breeds showed high linkage disequilibrium between the pair of CPE SNP, with all four breeds showing r2 = 1.0. The Brahman and Santa Gertrudis showed r2 ≤ 0.17. Both CPE:g.445C > T and CPE:g.601C > T SNP showed significant allele substitution effects to IMF in animals of taurine ancestry, with an allele substitution effect of α = 0.22, P = 0.020 for CPE:g.445C > T, explaining 0.4% of the phenotypic variance.
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Schutt, K. M., H. M. Burrow, J. M. Thompson, and B. M. Bindon. "Brahman and Brahman crossbred cattle grown on pasture and in feedlots in subtropical and temperate Australia. 1. Carcass quality." Animal Production Science 49, no. 6 (2009): 426. http://dx.doi.org/10.1071/ea08081.
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Brahmans are known to have poorer carcass quality relative to Bos taurus breeds and crossbreds under temperate environments; however, little is known of their performance in subtropical environments. The Cooperative Research Centre for Cattle and Beef Industry (Meat Quality) initiated a crossbred progeny test experiment to compare straightbred Brahmans with Brahman crossbreds finished on pasture and grain, in subtropical and temperate environments, to carcass quality specifications of Australian domestic and export markets. Brahman, Belmont Red, Santa Gertrudis, Angus, Hereford, Shorthorn, Charolais and Limousin sires were mated to Brahman females in subtropical Queensland over 3 years to produce 1750 progeny. At a common age at slaughter, Charolais crossbreds had the highest hot carcass weight (CWT) but were not significantly heavier than Limousin or British crossbred progeny. At common carcass weights, breeds within breed type (British, Continental, tropically adapted) performed similarly. British and Santa Gertrudis crossbreds had the fattest carcasses and lowest yields. British and Belmont Red crossbreds had the highest intramuscular fat percentage (IMF). Continental crossbreds had the highest retail beef yield (RBY), kilograms of retail primals (RTPM) and percent retail primals (pcRTPM) and leanest carcasses. Brahmans had the lowest CWT, intermediate subcutaneous fat cover, high yields and low IMF. Animals finished in the subtropics on pasture were significantly older, leaner and had higher RBY, RTPM and pcRTPM than subtropical feedlot-finished contemporaries. Temperate feedlot animals had significantly more IMF, less subcutaneous fat at the P8 site and slightly lower yields than subtropical feedlot contemporaries, indicating possible effects of postweaning growth path on fat distribution. Belmont Red crossbreds demonstrated the advantages of adaptation with the highest IMF in both subtropical finishing regimes, while Angus progeny had the highest IMF in the temperate feedlot environment and highest IMF overall when analysed across finishing regimes. Significant interactions were mainly the result of scale effects rather than breed re-ranking for carcass traits across markets and finishing regimes. Therefore, breeds that performed well for certain carcass traits in subtropical environments performed consistently for those traits in temperate environments relative to other sire breeds, regardless of market endpoint or finishing nutrition.
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Duarte-Ortuño, A., W. Thorpe, and A. Tewolde. "Reproductive performance of purebred and crossbred beef cattle in the tropics of Mexico." Animal Science 47, no. 1 (August 1988): 11–20. http://dx.doi.org/10.1017/s0003356100036990.
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AbstractRecords of beef cows on a ranch in south-east Mexico gave 1377 ages at first calving (AFC) and 3932 calving intervals (CI) for the comparison by least-squares analysis of the genetic groups: commercial zebu (CZ), Brahman, other zebu breeds and their zebu crosses (zebu), F, crosses born to zebu dams by Bos taunts or Santa Gertrudis sires, and 3/4 bred zebu and 3/4 Bos taurus. Subsamples of 1090 ages at first calving and 3154 intervals were analysed considering the breed groups: CZ, Brahman, Guzerat, Gyr and Indo-brazil, and the F1 crosses resulting from matings between these zebu breeds, Santa Gertrudis and Charolais as sire breeds and the CZ as the dam breed. Three populations were analysed for each model, the original ranch population and two populations reduced by retrospective culling. The original population had a mean AFC and CI of 1226 and 489 days respectively reduced by the first and second culling by 24 and 37 days and by 62 and 83 days respectively. Repeatability of CI increased from 0·06 to 0·11 and 0·14 respectively.Genetic group significantly influenced AFC. In the original population F1 heifers had a significantly younger AFC than Brahman and zebu heifers but not significantly younger than the other genetic groups. Heifers with 0·25, 0·75 and 1·00 zebu genes did not have significantly different AFCs. After the retrospective culling only the 3/4 bred zebus were significantly superior to the worst group, the zebus. The effect of breed group was only significant in the original population but generally the same rank order was maintained after the retrospective culling. F, Charolais × CZ heifers had the youngest AFC, a superiority of 67 days over CZ and 92 days over Brahman. Purebred zebus and their F, crosses with CZ did not calve earlier than CZ dams. Genetic group had a highly significant effect on CI. Females with 0·50 and 0·75 Bos taurus genes had shorter CIs than females with 0·75 and 1·00 zebu genes. The superiority was maintained after culling. Breed group had a significant effect in each population. F1 Charolais × CZ dams had the shortest CI. CZ had equivalent or shorter CI than all zebu breeds and their F1 crosses with CZ. Heterosis effects for AFC and CI in the zebu crosses were generally advantageous but small, while the heritabilities for the zebu population were negative for AFC and 0·05, 0·22 and 0·06 for CI in the original and two culled populations respectively.
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Kramarenko, A. S. "Genetic structure of the Southern meat cattle breed based on microsatellite markers." Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 21, no. 91 (November 6, 2019): 21–28. http://dx.doi.org/10.32718/nvlvet-a9104.
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The Southern Meat cattle is a composite breed developed by crossing Cuban zebu (Bos indicus) with different cattle breeds (Bos taurus) – local the Red Steppe, Hereford, Charolais, Santa Gertrudis, Dairy Shorthorn. Genetic structure of the Southern meat cattle breed from the State Enterprise Experimental Farm “Askaniyske” NAAS Ukraine (Kherson region) were investigated based on the microsatellite DNA loci. Analysis included 192 animals. A panel of 12 bovine-specific microsatellite markers (TGLA227, BM2113, TGLA53, ETH10, SPS115, TGLA122, INRA23, TGLA126, BM1818, ETH3, ETH225 and BM1824), recommended of the ISAG for cattle genetic diversity studies, was selected for genetic characterization and revealing the extent of genetic diversity in the Southern Meat cattle breed. Genomic DNA was extracted from tissue samples using Nexttec column (Nexttec Biotechnology GmbH, Germany) following the manufacturer's instructions. All laboratory tests were conducted in the laboratory of Molecular Genetics, Animal Center of Biotechnology and Molecular Diagnostics, All-Russian Research Institute for Animal Husbandry named after academy member L.K. Ernst. We report the distribution and the frequency of a taurine and an indicine specific alleles in the Southern Meat cattle breed using literature data about the Zebu and different cattle breeds genetic structure based on microsatellite loci from our list. It can be assumed that the TGLA22777, BM2113141-143, ETH10209-211, TGLA122149, INRA23194-198, TGLA126123, ETH225156-158-160 alleles among the Southern Meat cattle breed examined individuals were inherited from a B. indicus ancestor. On the other hand, the TGLA53156, ETH10217-219, TGLA122143, INRA23202, TGLA126115, ETH225148-150, BM1824188-190 alleles in the Southern Meat cattle gene pool may be inherited from a B. taurus ancestor (i.e., taurine breeds diagnostic alleles).
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Smith, Stephen B. "42 Carcass quality of cattle raised in tropical/subtropical environments." Journal of Animal Science 97, Supplement_3 (December 2019): 33. http://dx.doi.org/10.1093/jas/skz258.065.
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Abstract Cattle raised in tropical/subtropical environments typically are Bos indicus full blood or crossbred cattle. While they are ideally suited for reproductive performance in hot and humid climates, they frequently produce carcasses with lesser marbling scores than Bos taurus cattle. Early research from our laboratory compared subcutaneous (s.c.) and intramuscular (i.m.) adiposity and lipogenic capacity in Angus and Santa Gertrudis and Angus and Braford steers.; cattle with predominantly Bos indicus has lower marbling scores and smaller i.m. adipocytes. These and other studies suggested that genetic differences in adipose tissue metabolism between B. taurus and B. indicus breed types were expressed only when there were visible differences in marbling score and adjusted fat thickness (AFT). A subsequent study suggested that fatty acid Δ9 desaturase enzyme activity [stearoyl-CoA desaturase (SCD)] was greater in adipose tissue from Bos indicus cattle than in Bos taurus cattle, thereby resulting in a greater proportion of oleic acid (18:1n-9). We recently reported a comprehensive study comparing three-fourths Brahman progeny to three-fourths Angus progeny, in which progeny were raised to a constant age and constant AFT. Subcutaneous adipocyte cell was similar between Brahman and Angus progeny (276 vs 288 pL) but i.m. adipocytes were smaller in Brahman progeny than in Angus progeny (170 vs 207 pL). This was consistent with the lower marbling scores of the Brahman progeny. There was no difference between the proportions of stearic acid (18:0) and oleic acid between Brahman and Angus progeny; nor was there a difference in s.c. or i.m. adipose tissue SCD activity. We conclude that time on feed and/or animal age has a greater impact on fatty acid than genetics (Brahman vs Angus). However, research has demonstrated consistently that i.m adipose tissue in Bos indicus cattle does not develop to the same extent as in Bos taurus cattle.
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Okamoto, Lillian L., Caleb C. Reichhardt, Anthony F. Alberto, Laura A. Motsinger, Sarah A. Bayles, Bryce W. Roholt, Matthew D. Garcia, and Kara J. Thornton. "PSII-A-3 Effect of Beef Breed Type Relative to Feedlot Performance, Feeding Behavior, and Carcass Characteristics." Journal of Animal Science 100, Supplement_3 (September 21, 2022): 263. http://dx.doi.org/10.1093/jas/skac247.477.
Full textAbstract:
Abstract Cattle production in the U.S. is being impacted by the changing global climate and limited availability of natural resources. Improving the efficiency of cattle production is imperative to make the most of these limited resources. Increasing the percentage of Bos indicus (BI) genetics within cattle herds is one potential method to address these issues, as they are able to withstand higher temperatures, are better adapted to nutritional stress, and consume less water than Bos taurus (BT) influenced cattle. The objective of this study was to examine steers of different breed types relative to feedlot performance, feeding behavior, and carcass characteristics. This study utilized a total of 115 steers of two different breeds: Angus (AN; n=83; 100% BT) and Santa Gertrudis influenced (SG; n=32; 19% BI, 81% BT). Steers were stratified by weight and randomly divided into one of four covered pens. Each pen was equipped with two GrowSafe bunks and all steers were fed the same typical ration. All steers were harvested at a commercial facility once industry average backfat standards were met. Individual dry matter intake and feeding behaviors were collected through the GrowSafe system. Weight, ribeye fat thickness, marbling score, and USDA yield grades were also assessed. Breed did not have an effect (P >0.10) on dry matter intake, average daily gain, ribeye fat thickness, hot carcass weight, or USDA yield grade. There was a tendency (P=0.09) for SG steers to spend more time with their heads down during individual GrowSafe bunk visits. Intramuscular fat was increased (P=0.0019) in AN steers compared to SG steers. Further research focused on genomic differences between cattle of different breed types is warranted to better understand the relationship between breed type and production performance characteristics.
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Brown, Bailee, Laura A. Motsinger, Caleb C. Reichhardt, Gordon K. Murdoch, Brenda M. Murdoch, Matthew D. Garcia, and Kara J. Thornton. "PSII-A-4 Effects of Beef Cattle Breed Type and Steroid Hormones on Proliferation Rates of Bovine Satellite Cells." Journal of Animal Science 100, Supplement_3 (September 21, 2022): 262. http://dx.doi.org/10.1093/jas/skac247.475.
Full textAbstract:
Abstract As the population increases, it is necessary to improve the sustainability of beef production. Bos indicus (BI) cattle are better adapted to nutritional stress, consume less water, and are better able to withstand thermal stress when compared to Bos taurus (BT) cattle. Additionally, anabolic implants, which typically contain the steroid hormones trenbolone acetate (TBA) and/or estradiol (E2), are commonly administered to beef cattle in the U.S. to improve production. The objective of this study was to determine the effects of cattle breed type and steroid hormones on proliferation of primary bovine satellite cells (BSC). Primary BSC were isolated from the Semimembranosus muscle of Angus (AN; n=2; 100% BT) and Santa Gertrudis (SG; n=2; 19% BI, 81% BT) yearling backgrounded steers and cultured. After the cells reached 70% confluency, cultures were treated with 1% fetal bovine serum (control), 10 nM TBA, 10 nM E2, or 10 nM TBA and E2 and proliferation rates were compared to control cultures. No treatment x breed interaction (P=0.17) was observed. Cultures from AN steers had increased (P=0.007) proliferation rates compared to cultures from SG steers. Steroid hormones increased (P=0.08) proliferation rates, regardless of breed. However, based on this preliminary data, trends are indicating that a breed*treatment interaction is present such that BSC isolated from AN steers are more responsive to treatment than BSC isolated from SG steers. Additional research needs to be completed to determine whether this interaction is still present once more replicates are completed, whether different hormone concentrations affect BSC from cattle of different breed types, and/or the effects of hormone treatment and breed type on BSC relative to differentiation and protein synthesis rate.
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Santana, Márcia Cristina Araújo, Bruno Ramalho Vieira, Diogo Fleury Costa, Paulo Henrique Moura Dian, Giovani Fiorentini, Roberta Carrilho Canesin, Gener Tadeu Pereira, Ricardo Andrade Reis, and Telma Teresinha Berchielli. "Source and frequency of dry season lipid supplementation of finishing grazing cattle." Animal Production Science 55, no. 6 (2015): 745. http://dx.doi.org/10.1071/an13458.
Full textAbstract:
The objective of this study was to evaluate the effects of sources of soybean oil [ground soybean (GS), soybean oil (SO) and calcium salts of soybean oil (CS)] on DM intake (DMI), ingestive behaviour and average daily gain (ADG) of heifers grazing marandu palisadegrass (Brachiaria brizantha cv. Marandu) supplemented in two frequencies [daily and 3 days a week (Monday, Wednesday and Friday – MWF)]. The experiment was conducted from July until November of 2007. Forty-two crossbred heifers (1/4 Nellore × 1/4 Santa Gertrudis × 1/2 Braunvieh), 17-months old and 297.1 kg ± 30.5 BW ± s.e.m., were used. Supplements were offered at 0.75% BW.day. Treatments were allocated in a completely randomised design and distributed in a factorial arrangement (3 × 2 – SO from three different sources and two supplementation frequencies). Total DMI was greater in August and October (2.2 kg DM/kg BW) than in November (1.5 kg DM/kg BW). There was an effect of SO source on total DM, herbage and nutrients intake, but no effects of supplementation frequency. The animals supplemented with SO had greater DMI (P < 0.05) than the ones fed GS and CS. Average daily gain (0.580 g) was not affected by supplement sources or feeding frequency. Therefore, GS and CS are more efficient supplements. Supplementation frequency altered grazing time differently according to source. The MWF treatment resulted in a decreased grazing time when GS and SO were fed. However, in days when supplements were not offered, grazing time was increased for GS and CS. It was concluded that a decreased frequency of supplementation may be implemented without effect on weight gain and will reduce labour and machinery costs.
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Robinson, D. L., D. M. Ferguson, V. H. Oddy, D. Perry, and J. Thompson. "Genetic and environmental influences on beef tenderness." Australian Journal of Experimental Agriculture 41, no. 7 (2001): 997. http://dx.doi.org/10.1071/ea00039.
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Mechanical tenderness measurements of M. longissimus (LM) and M. semitendinosus (ST) were analysed from 1392 tropically adapted (Brahman, Belmont Red and Santa Gertrudis) cattle grown out and finished in both tropical and temperate environments, and 2408 temperate breed (Angus, Hereford, Murray Grey and Shorthorn) cattle grown out and finished in a temperate environment. Groups of cattle from both environments were managed under 2 finishing systems (pasture and feedlot) to market liveweights of 400, 520 (steers and heifers) and 600 kg (steers only). Carcasses were electrically stimulated and care was taken to minimise stress before slaughter. Estimated genetic variation (GV) of compression of unaged LM and ST muscles was 0.006 and 0.018 kg2 respectively in tropically adapted and 0.004 and 0.009 kg2 in temperate breeds (phenotypic means 1.7, 2.1, 1.6, 2.1 kg; heritabilities, h2 = 0.16, 0.24, 0.10, 0.16). Estimated GV for LM and ST shear force was 0.24 and 0.12 kg2 in tropically adapted and 0.06 and 0.02 kg2 in temperate breeds (means 4.3, 4.6, 4.0 and 4.7 kg; h2 = 0.38, 0.40, 0.11, 0.06). Genetic correlations among shear and compression forces of the ST and LM ranged from 0.28 to 0.95 in tropically adapted and –0.20 to 0.60 in temperate breeds. The fixed effects model (market, finish, breed, birth herd, management group and interactions) explained about half the variation in compression measurements, but only 16% and 27% of the variation of LM shear force in tropically adapted and temperate breeds. The relatively low genetic variation and inconsistent genetic correlations in temperate breeds suggest genetic improvement in tenderness may be less important than effective pre- and post-slaughter management protocols. The higher additive genetic variances and moderate heritabilities in tropically adapted breeds suggest genetic improvement is possible but this will be most effective if combined with effective control of slaughter protocols.
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Corbet, N. J., J. M. Allen, A. R. Laing, G. Fordyce, M. R. McGowan, and B. M. Burns. "Using ultrasound to derive new reproductive traits in tropical beef breeds: implications for genetic evaluation." Animal Production Science 58, no. 9 (2018): 1735. http://dx.doi.org/10.1071/an16616.
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Key components of female fertility in tropically adapted beef breeds are age at puberty and interval from calving to conception. Presence of an ovarian corpus luteum or stage of pregnancy were recorded using trans-rectal ultrasonography in 4649 heifers and 2925 first-lactation cows in seven herds of either Brahman, Droughtmaster or Santa Gertrudis tropical beef cattle breeds in northern Australia. The traits derived from a single ultrasonographic examination were incidence of corpus luteum at ~600 days of age in heifers, and weeks pregnant 5 weeks post-mating in heifers at ~2.5 years of age and in first-lactation cows at either 2.5 or 3.5 years of age. At 600 days of age, the bodyweight of heifers averaged 340 kg and 40% had a corpus luteum. At 2.5 years of age bodyweight of heifers averaged 452 kg and 80% were pregnant. First-lactation cows averaged 473 kg and 64% were pregnant. Considerable between-herd variation in traits reflected differences in climate and management at each site. However, estimates of heritability of incidence of corpus luteum at 600 days (0.18–0.32) and weeks pregnant in lactating cows (0.11–0.20) suggested that a significant proportion of the variation was due to additive gene action. Small to moderate genetic correlations with other economically important traits and the range in estimated breeding values indicate substantial opportunity for genetic improvement of the traits. The study provided evidence to accept the hypothesis that strategically timed ultrasound examinations can be adopted to derive useful traits for genetic evaluation.
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Santana, M. C. A., G. Fiorentini, J. D. Messana, P. H. M. Dian, R. C. Canesin, R. A. Reis, and T. T. Berchielli. "Different forms and frequencies of soybean oil supplementation do not alter rumen fermentation in grazing heifers." Animal Production Science 57, no. 3 (2017): 530. http://dx.doi.org/10.1071/an14608.
Full textAbstract:
Over the productive cycle, the performance of cattle in grazing systems may be compromised, and feed supplementation is a strategy to establish nutritional balance and maximise the performance of grazing animals. The objective of this study was to evaluate the effect of different supplementation frequencies (i.e. daily supplementation (DS) versus Monday, Wednesday and Friday (MWF)) with different forms of soybean oil (i.e. soybean grain (SG), soybean oil (SO) and rumen-protected fat (RPF)) on the nutrient digestion and rumen fermentation of heifers grazing Brachiaria brizantha cv. Marandu pastures. Twelve crossbred heifers (1/4 Nellore × 1/4 Santa Gertrudis × 1/2 Braunvieh) with an initial bodyweight of 236.3 ± 27.6 kg were distributed in a completely randomised design with a factorial arrangement 3 × 2 (three diets and two supplementation frequencies). There was no interaction among the SO form or supplementation frequency on dry matter intake and dry matter digestibility (P > 0.05). The animals supplemented with SG exhibited lower nitrogen intake and absorption compared with animals that were fed SO (P < 0.05). The efficiency of microbial synthesis was not influenced by the diet or supplementation frequency (P > 0.05). Forms of SO affected the rumen pH; animals fed SO showed pH values similar to those of animals receiving SG but lower values than animals fed RPF (P < 0.05). Animals supplemented with DS exhibited higher levels of rumen ammonia nitrogen relative to those supplemented MWF. The reduction of supplementation frequency (from DS to MWF k) in our experimental conditions can be used to increase the efficiency of pasture utilisation without effects in fermentation activity of the rumen microbial population. Supplementation with SO is a strategy to increase propionic acid concentration and reduce A : P ratio, which is an indicator of improvement of the efficiency of the ruminal energy utilisation.
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Kadel, Meridy J., David J. Johnston, Heather M. Burrow, Hans-U. Graser, and Drewe M. Ferguson. "Genetics of flight time and other measures of temperament and their value as selection criteria for improving meat quality traits in tropically adapted breeds of beef cattle." Australian Journal of Agricultural Research 57, no. 9 (2006): 1029. http://dx.doi.org/10.1071/ar05082.
Full textAbstract:
Flight time, an objective measure of temperament, was recorded in 3594 Brahman, Belmont Red, and Santa Gertrudis heifers and steers. Two subjective measures of temperament (crush score and flight speed score) were also available for over 2000 of these animals. Temperament measures were recorded post-weaning (average age 8 months) and again at the start of finishing (average age 19 months) on a subset of the animals. Nine meat quality traits were measured on these animals and included measures on 2 different muscles [M. longissimus thoracis et lumborum (LTL) and M. semitendinosus (ST)]. The heritability of flight time measured post-weaning and at the start of finishing was 0.30 and 0.34, respectively, with a repeatability of 0.46 across the measurement times. Heritabilities for scored temperament traits were 0.21, 0.19, and 0.15 for post-weaning flight speed score, post-weaning crush score, and start of finishing crush score, respectively. Genetic correlations across measurement times for flight time were 0.98 and 0.96 for crush score, indicating a strong underlying genetic basis of these temperament measures over time; however, the corresponding phenotypic correlations were lower (0.48 and 0.37, respectively). Longer flight times (i.e. better temperament) were genetically correlated with improved tenderness (i.e. lower shear force and higher tenderness scores), with genetic correlations of –0.42 and 0.33 between LTL shear force, and Meat Standards Australia (MSA) tenderness, respectively. Genetic correlations between post-weaning crush score and the same meat quality traits were 0.39 and –0.47, respectively. However, genetic and phenotypic correlations between measures of temperament and other meat quality traits were generally low, with the exception of crush scores with LTL Minolta a* value (–0.37 and –0.63 for post-weaning and start of finishing measurement time, respectively). Predicted correlated responses of –0.17 kg LTL shear force and 2.6 MSA tenderness points per generation were predicted based on the genetic parameter estimates and a recording regime of both flight time and crush scores. Selection based on the measures of temperament described in this study could be used to improve temperament itself and correlated improvements can also occur in meat tenderness and eating quality traits in tropically adapted breeds of cattle.
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Shackelford, Steven D., Andy King, Warren Snelling, Tara G. McDaneld, Larry A. Kuehn, Gary L. Bennett, and Tommy Wheeler. "118 Awardee Talk - Genomic control of fatty acid profile in beef." Journal of Animal Science 97, Supplement_3 (December 2019): 108. http://dx.doi.org/10.1093/jas/skz258.222.
Full textAbstract:
Abstract Steers (n = 868) were raised, feedlot-finished with ad libitum access to a high-energy diet and harvested to determine if there is genomic control of fatty acid profile traits in beef breeds common to the United States. Cattle included purebred and crossbred progeny of Angus, Red Angus, Hereford, Shorthorn, Simmental, Charolais, Limousin, Gelbvieh, Maine Anjou, Chiangus, Braunvieh, Salers, Brahman, Brangus, Santa Gertrudis, and Beefmaster as well as three composite lines. Either directly or through imputation, genotypes were determined for > 133,000 functional single nucleotide polymorphisms (SNP). At approximately 38 h postmortem, a 2.54-cm-thick longissimus steak was obtained from the 13th rib region of the left side of each carcass. At 14 d postmortem, steaks were cooked and subsequently longissimus was pulverized in liquid nitrogen. Fatty acid profile was determined by gas chromatography and mass spectrometry. A genome-wide association study was conducted for fatty acid profile traits expressed as a deviation from the contemporary group mean using the Mixed Linear Model Analysis of SNP & Variation Suite 8.8.3 (Golden Helix) and Pre-computed Kinship Matrix using the GBLUP Genomic Relationship Matrix. A SNP in coiled coil domain containing 57 (CCDC57; Chromosome 19 at 51,349,695) affected the percentage of C14:0 (P < 10–46), short-chain fatty acids (P < 10–36), and saturated fatty acids (P < 10–17). Also, a SNP in thyroid hormone responsive (THRSP; Chromosome 29 at 18,090,403) affected the percentage of C14:0 (P < 10–16) and short-chain fatty acids (P < 10-10). The percentage of polyunsaturated fatty acids was affected by SNP in myostatin (Chromosome 2 at 6,213,980; P < 10–15). These results show that fatty acid profile of beef can be changed through genetic selection but, it is not clear if the level of change will be great enough to impact human health.
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Schutt, K. M., H. M. Burrow, J. M. Thompson, and B. M. Bindon. "Brahman and Brahman crossbred cattle grown on pasture and in feedlots in subtropical and temperate Australia. 2. Meat quality and palatability." Animal Production Science 49, no. 6 (2009): 439. http://dx.doi.org/10.1071/ea08082.
Full textAbstract:
Market demand for a reliable supply of beef of consistently high eating quality led the Cooperative Research Centre for Cattle and Beef Industry (Meat Quality) to initiate a crossbreeding progeny test program to quantify objective and sensory meat quality differences between straightbred and first-cross Brahman cattle. Brahman, Belmont Red, Santa Gertrudis, Angus, Hereford, Shorthorn, Charolais and Limousin sires were mated to Brahman females over 3 years to produce 1346 steers and heifers in subtropical northern Australia. Calves were assigned within sire by age and weight to one of three market endpoints (domestic, Korean or Japanese), one of two finishing environments (subtropical or temperate) and one of two finishing diets (pasture or feedlot). Average carcass weights were 227, 288 and 327 kg for domestic, Korean and Japanese markets respectively. Only steers were finished for the Japanese market. The effects of sire breed, finishing regime, market endpoint and sex on sensory meat quality of four attributes score (CMQ4), ossification score and Warner-Bratzler shear force (SF), instron compression (IC), ultimate pH and percent cooking loss (CL) on the M. longissimus thoracis et lumborum (LT) and M. semitendinosus (ST) were determined. Straightbred Brahmans had the highest SFLT (5.39 ± 0.07; P < 0.001), ICLT (1.89 ± 0.02; P < 0.05) and CL in both muscles (P < 0.05). Straightbred Brahmans were the only genotype that failed to meet minimum CMQ4 grading standards (38.3; P < 0.001). Progeny with up to 75% Brahman content successfully met minimum objective and sensory meat quality consumer thresholds for tenderness (IC <2.2 kg, SF <5.0 kg; CMQ4 >46.5). There was little difference between crossbred progeny for most meat quality traits. All feedlot-finished animals were slaughtered at domestic, Korean and Japanese market weights by 24 months of age, with minimal differences in objective measures of meat quality between markets. The IC measures for all sire breeds were below 2.2 kg, indicating connective tissue toughness was not an important market consideration in feedlot-finished animals slaughtered by 24 months of age. Pasture finishing adversely affected all meat quality traits (P < 0.001) except CLST, with Korean and Japanese market animals having unacceptably tough SF, IC and CMQ4 measures. This was attributed to their older age at slaughter (31 and 36 months respectively), resulting from their seasonally interrupted growth path. While domestic animals slaughtered at 25 months of age off pasture had unacceptably high SF and IC, CMQ4 was acceptable. Subtropical feedlot animals had slightly more desirable (n.s.) SF and IC relative to temperate feedlot animals, whereas temperate feedlot animals had higher CMQ4 (P < 0.001). Genotype × environment interactions were not important.
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Johnson, Jocelyn R., Gordon E. Carstens, Wimberly K. Krueger, Phillip A. Lancaster, Erin G. Brown, Luis O. Tedeschi, Robin C. Anderson, Kristen A. Johnson, and Arieh Brosh. "Associations between residual feed intake and apparent nutrient digestibility, in vitro methane-producing activity, and volatile fatty acid concentrations in growing beef cattle1." Journal of Animal Science 97, no. 8 (June 7, 2019): 3550–61. http://dx.doi.org/10.1093/jas/skz195.
Full textAbstract:
Abstract The objectives of this study were to examine the relationship between residual feed intake (RFI) and DM and nutrient digestibility, in vitro methane production, and volatile fatty acid (VFA) concentrations in growing beef cattle. Residual feed intake was measured in growing Santa Gertrudis steers (Study 1; n = 57; initial BW = 291.1 ± 33.8 kg) and Brangus heifers (Study 2; n = 468; initial BW = 271.4 ± 26.1 kg) fed a high-roughage-based diet (ME = 2.1 Mcal/kg DM) for 70 d in a Calan-gate feeding barn. Animals were ranked by RFI based on performance and feed intake measured from day 0 to 70 (Study 1) or day 56 (Study 2) of the trial, and 20 animals with the lowest and highest RFI were identified for subsequent collections of fecal and feed refusal samples for DM and nutrient digestibility analysis. In Study 2, rumen fluid and feces were collected for in vitro methane-producing activity (MPA) and VFA analysis in trials 2, 3, and 4. Residual feed intake classification did not affect BW or BW gain (P > 0.05), but low-RFI steers and heifers both consumed 19% less (P < 0.01) DMI compared with high-RFI animals. Steers with low RFI tended (P < 0.1) to have higher DM digestibility (DMD) compared with high-RFI steers (70.3 vs. 66.5 ± 1.6% DM). Heifers with low RFI had 4% higher DMD (76.3 vs. 73.3 ± 1.0% DM) and 4 to 5% higher (P < 0.01) CP, NDF, and ADF digestibility compared with heifers with high RFI. Low-RFI heifers emitted 14% less (P < 0.01) methane (% GE intake; GEI) calculated according to Blaxter and Clapperton (1965) as modified by Wilkerson et al. (1995), and tended (P = 0.09) to have a higher rumen acetate:propionate ratio than heifers with high RFI (GEI = 5.58 vs. 6.51 ± 0.08%; A:P ratio = 5.02 vs. 4.82 ± 0.14%). Stepwise regression analysis revealed that apparent nutrient digestibilities (DMD and NDF digestibility) for Study 1 and Study 2 accounted for an additional 8 and 6%, respectively, of the variation in intake unaccounted for by ADG and mid-test BW0.75. When DMD, NDF digestibility, and total ruminal VFA were added to the base model for Study 2, trials 2, 3, and 4, the R2 increased from 0.33 to 0.47, explaining an additional 15% of the variation in DMI unrelated to growth and body size. On the basis of the results of these studies, differences in observed phenotypic RFI in growing beef animals may be a result of inter-animal variation in apparent nutrient digestibility and ruminal VFA concentrations.
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Kozyr, V. S. "FORMATION OF PHENOTYPICAL FEATURES OF BULLS OF IMPORTED MEAT BREEDS OF DIFFERENT ECOLOGICAL AND GENETIC ORIGIN IN THE STEPPE OF UKRAINE." Animal Husbandry of the Steppe of Ukraine 1, no. 1 (October 11, 2022): 6–12. http://dx.doi.org/10.31867/2786-6750.1.1.2022.6-12.
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To studied the meat productivity of bulls of Men-Anjou, Kian and Santa Gertrude breeds in the Experimental Farm “Polyvanivka” of SЕ Institute of Grain Crops of NAAS. Growing condition, keeping technology, level of feeding were the same. Up to 18 months, animals were kept loose, and later – on a leash. The diet was balanced according to the norm of A-UIL traditional forages for Steppe zone. Animals were slaughtered at 18, 24 and 30 months of age by 5 bulls from each group. The studies used zootechnical, biological, analytical, biochemical, morphological, biometric methods.
It is proved that in order to make more efficient use of livestock and obtain high-quality competitive beef to improve the supply of meat to the population, it is advisable to grow bulls up to 2.5 years of age. At the same time, clinical indicators and indicators of animals’ blood biochemistry were normal. In terms of growth energy and feed conversion at all ages, Men-Anjou dominates, bulls reach a weight of 600 kg (or more) earlier than other peers due to the massiveness and habitus of their body, they have a greater mass of carcasses, internal fat, offal and skin, resulting in higher slaughter yield. The differences in the coefficient of meat, chemical composition of beef, and its culinary and taste qualities are insignificant. Under the conditions of the Ukrainian steppe, bulls of Men-Anjou, Kian and Santa Gertruda breeds showed productive and slaughter qualities characteristic of their genotypes during the formation of phenotypic traits. Imported breeds can be a source of genetic diversity in the development of beef cattle breeding in Ukraine.
The beef of all studied bulls’ breeds meets is in a widely commercial demand. These breed of bulls steady pass on their positive traits to offspring, which can be used in the formation of Beef Cattle Breeding in Ukraine. Raising animals of the Men-Anjou, Kian and Santa Gertrude breeds up to 2.5 years of age will increase the production of high-quality beef in order to improve the supply of meat to the population and strengthen the country's food security.
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Reverter, A., D. J. Johnston, D. Perry, M. E. Goddard, and H. M. Burrow. "Genetic and phenotypic characterisation of animal, carcass, and meat quality traits from temperate and tropically adapted beef breeds. 2. Abattoir carcass traits." Australian Journal of Agricultural Research 54, no. 2 (2003): 119. http://dx.doi.org/10.1071/ar02086.
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A total of 11 abattoir carcass measures were recorded on 7854 carcasses in temperate (TEMP) and tropically adapted (TROP) beef breeds. Breeds for TEMP included Angus, Hereford, Murray Grey, and Shorthorn; Brahman, Belmont Red, and Santa Gertrudis accounted for TROP breeds. Measurements included carcass weight (CWT), retail beef yield percentage (RBY), intramuscular fat percentage (IMF), subcutaneous fat depth at the P8 site (P8) and at 12/13th rib (RIB), eye muscle length by width (ELW), deep butt temperature (DBTEMP), fat colour score (FATC), meat colour score (MEATC), marbling score (MARB), and carcass muscle score (MUSC). Animals were finished to 3 different market weight endpoints, either on pasture or in a feedlot, and in different geographic regions for the TROP breeds. Both the phenotypic and genetic expressions of the traits were estimated at each level of market weight endpoint and finishing regime. Heritabilities (h2), and genetic (rg) and phenotypic (rp) correlations between traits were estimated for TEMP and TROP separately. The design effects of market weight endpoint and finishing regimes were the most important sources of variation for continuously measured traits. Main effects for the scored traits were finishing regime for FATC and MEATC and market weight endpoint for MARB and MUSC. Feedlot finished cattle had the whitest FATC and the lightest MEATC. For TEMP, estimates of h2 for CWT, RBY, IMF, P8, RIB, ELW, DBTEMP, FATC, MEATC, MARB, and MUSC were 0.39, 0.57, 0.38, 0.36, 0.27, 0.30, 0.10, 0.05, 0.11, 0.17, and 0.14, respectively. In comparison, h2 for the same order of traits for TROP were 0.36, 0.50, 0.39, 0.30, 0.41, 0.32, 0.04, 0.09, 0.11, 0.25, and 0.11. The direction and magnitude of rg between traits were similar for TEMP and TROP, particularly between CWT, RBY, IMF, P8, and RIB. Genetic correlations of RBY were moderate and negative with all measures of fatness, including IMF (–0.38 TEMP and –0.43 TROP). Positive rg existed between all measures of fatness, with MARB and IMF close to unity. Negative rg was estimated between CWT and all fat measurements. Also negative were the rg and rp estimates between CWT and MEATC. For all traits in both TEMP and TROP, domestic weight carcasses exhibited lower additive variance than export market carcasses. However, genetic correlations between traits across market weight endpoints were positive and close to unity, with the exception of RBY for TROP. For TEMP breeds, genetic correlations between finishing regimes were close to unity. However, possible genotype by environment interactions were found for TROP for P8, MEATC, and MARB between finishing in different geographic regions, and between feedlot and pasture finished animals for RBY and MEATC. Genetic improvement of carcass traits is a possibility given the moderate heritabilities, moderate to strong genetic correlations, and little evidence of genotype by environment interactions.
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Baimukanov, D. A., V. G. Semenov, S. D. Nurbaev, M. Prmanshayev, M. A. Kalghimbayeva, and A. B. Nazarbekov. "Inter-population genetic diversity of cattle of the Kazakhstan population of Santa Gertrude Breed of Zhetysu type by microsatellite DNA." IOP Conference Series: Earth and Environmental Science 604 (December 2, 2020): 012043. http://dx.doi.org/10.1088/1755-1315/604/1/012043.
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Fortes, Marina, Wei Liang Andre Tan, Laercio R. Porto-Neto, Antonio Reverter, and Gry B. Boe-Hansen. "272 Proposing a combination of heritable fertility traits for bull selection." Journal of Animal Science 98, Supplement_4 (November 3, 2020): 83–84. http://dx.doi.org/10.1093/jas/skaa278.153.
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Abstract Traits such as sperm morphology and motility are routine in veterinarian evaluations of bull fertility. However, they rarely are included in livestock breeding programs, which typically use only scrotal circumference (SC) and some female traits for fertility selection. We studied 25 male fertility traits measured in two research populations of bulls (1,099 Brahman, and 1,719 Tropical Composite) and one commercial population (2,490 Santa Gertrude bulls). Measurements included standard semen evaluation (e.g. sperm motility and morphology) and SC. In the research data, we also measured sperm DNA fragmentation and sperm protamine deficiency for about 50% of the bulls. Using a mixture of genomic and pedigree analyses, we estimated heritabilities and genetic correlations for all traits, in each population. Our analyses suggest that bull fertility traits have a heritable component, which makes selective breeding possible. The phenotype variation in sperm DNA fragmentation and sperm protamine deficiency traits also have a heritable component (h2 ~ 0.05–0.22). These first estimates for heritability of sperm chromatin phenotypes require further studies, with larger datasets, to corroborate present results. In all three populations, we observed genetic correlations across traits that were favorable, but not high. For example, the percentage of normal sperm (PNS) from the sperm morphology evaluation was positively correlated with SC. In the research data, sperm DNA fragmentation was negatively correlated with PNS (r2 ~ 0.23–0.33), meaning that bulls with a higher PNS had less DNA fragmentation, being therefore more fertile according to both indicators. Given the favorable and yet not high genetic correlations between traits, it is possible to envision that sperm chromatin phenotypes might form a panel, together with PNS and SC, for a comprehensive bull fertility index. Selection indices that include fertility traits are being implemented in the dairy industry and could be recommended for beef cattle, too. An index that benefits from the favorable genetic correlations between traits that describe different aspects of bull fertility is a sensible approach to selective breeding. The clinical use of complementary indicators for male fertility is largely accepted, when deciding on bull fitness for the mating season. We propose extending this rationale to create a multi-trait index that captures genetic merit for bull fertility. In addition, we performed genome-wide association analyses in the research data and identified eight QTLs in the X chromosome. Correlations and shared SNP associations support the hypothesis that these phenotypes have the same underlying cause: abnormal spermatogenesis. In conclusion, it is possible to improve bull fertility through selective breeding, by measuring complementary fertility traits. Genomic selection for bull fertility might be more accurate if the X chromosome mutations that underlie the discovered QTL are included in the analyses. Polymorphisms associated with fertility in the bull accumulate in the X chromosome, as they do in humans and mice, thus suggesting specialization of this chromosome.
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Vahedi, Seyed Milad, Siavash Salek Ardestani, Kian Pahlevan Afshari, Seyed Mohammad Ghoreishifar, Sima Moghaddaszadeh-Ahrabi, Mohammad Hossein Banabazi, and Luiz Fernando Brito. "Genome-Wide Selection Signatures and Human-Mediated Introgression Events in Bos taurus indicus-influenced Composite Beef Cattle." Frontiers in Genetics 13 (May 30, 2022). http://dx.doi.org/10.3389/fgene.2022.844653.
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Genetic introgression from interbreeding hybridization of European Bos taurus taurus (EBT) and Indian Bos taurus indicus (IBI) cattle breeds have been widely used to combine the climatic resilience of the IBI cattle and the higher productivity of EBT when forming new composite beef cattle (CB) populations. The subsequent breeding strategies have shifted their initial genomic compositions. To uncover population structure, signatures of selection, and potential introgression events in CB populations, high-density genotypes [containing 492,954 single nucleotide polymorphisms (SNPs) after the quality control] of 486 individuals from 15 cattle breeds, including EBT, IBI, and CB populations, along with two Bos grunniens genotypes as outgroup were used in this study. Then, in-depth population genetics analyses were performed for three CB breeds of Beefmaster, Brangus, and Santa Gertrudis. Neighbor-joining, principal components, and admixture analyses confirmed the historical introgression of EBT and IBI haplotypes into CB breeds. The fdM statistics revealed that only 12.9% of CB populations’ genetic components are of IBI origin. The results of signatures of selection analysis indicated different patterns of selection signals in the three CB breeds with primary pressure on pathways involved in protein processing and stress response in Beefmaster, cell proliferation regulation and immune response in Brangus, and amino acids and glucose metabolisms in Santa Gertrudis. An average of >90% of genomic regions underlying selection signatures were of EBT origin in the studied CB populations. Investigating the CB breeds’ genome allows the estimation of EBT and IBI ancestral proportions and the locations within the genome where either taurine or indicine origin alleles are under selective pressure. Such findings highlight various opportunities to control the selection process more efficiently and explore complementarity at the genomic level in CB populations.
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Raza, Ali, Benjamin L. Schulz, Amanda Nouwens, Lousie A. Jackson, Emily K. Piper, Peter James, Nicholas N. Jonsson, and Ala E. Tabor. "Serum proteomes of Santa Gertrudis cattle before and after infestation with Rhipicephalus australis ticks." Parasite Immunology 43, no. 7 (April 11, 2021). http://dx.doi.org/10.1111/pim.12836.
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Ribeiro, André Mauric F., Leticia P. Sanglard, Warren M. Snelling, R. Mark Thallman, Larry A. Kuehn, and Matthew L. Spangler. "Genetic parameters, heterosis, and breed effects for body condition score and mature cow weight in beef cattle." Journal of Animal Science 100, no. 2 (January 19, 2022). http://dx.doi.org/10.1093/jas/skac017.
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Abstract Understanding the genetic relationship between mature cow weight (MWT) and body condition score (BCS) is useful to implement selection programs focused on cow efficiency. The objectives of this study were to estimate genetic parameters, heterosis, and breed effects for MWT and BCS. In total, 25,035 and 24,522 overlapping records were available for MWT and BCS on 6,138 and 6,131 cows, respectively, from the Germplasm Evaluation program, a crossbred beef population at the U.S. Meat Animal Research Center. Pedigree was available for 48,013 individuals. Univariate animal models were used to estimate heritabilities for each trait by parity. Bivariate animal models were used to estimate genetic correlations between parities within a trait and between traits within parities. Bivariate repeatability animal models were used to estimate genetic correlations between traits across parities. Estimates of heritability for different parities ranged from 0.43 ± 0.05 to 0.55 ± 0.07 for MWT and from 0.12 ± 0.03 to 0.25 ± 0.04 for BCS and were lower with the repeatability model at 0.40 ± 0.02 and 0.11 ± 0.01 for MWT and BCS, respectively. Estimates of repeatability were high for MWT (0.67 ± 0.005) and low for BCS (0.22 ± 0.006). Estimates of genetic correlation for MWT and BCS between parities were, in general, high, especially between consecutive parities. Estimates of genetic correlation between MWT and BCS were positive and moderate, ranging from 0.32 ± 0.09 to 0.68 ± 0.14. The direct heterosis estimates were 21.56 ± 3.53 kg (P ≤ 0.001) for MWT and 0.095 ± 0.034 (P ≤ 0.001) for BCS. Ordered by decreasing MWT, the breeds ranked Brahman, Charolais, Angus, Simmental, Salers, Hereford, Santa Gertrudis, Chiangus, Brangus, Red Angus, Shorthorn, Maine-Anjou, Gelbvieh, Beefmaster, Limousin, and Braunvieh. Ordered by decreasing BCS, the breeds ranked Brahman, Red Angus, Charolais, Angus, Hereford, Brangus, Beefmaster, Chiangus, Salers, Simmental, Maine-Anjou, Limousin, Santa Gertrudis, Shorthorn, Gelbvieh, and Braunvieh. Estimates of breed differences for MWT were also adjusted for BCS (AMWT), and in general, AMWT depicted smaller differences between breeds with some degree of re-ranking (r = 0.59). These results suggest that MWT and BCS are at least moderately genetically correlated and that they would respond favorably to selection. Estimates of breed differences and heterotic effects could be used to parameterize multibreed genetic evaluations for indicators of cow maintenance energy requirements.
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Crum, Tamar E., Robert D. Schnabel, Jared E. Decker, and Jeremy F. Taylor. "Taurine and Indicine Haplotype Representation in Advanced Generation Individuals From Three American Breeds." Frontiers in Genetics 12 (October 18, 2021). http://dx.doi.org/10.3389/fgene.2021.758394.
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Development of the American Breeds of beef cattle began in the 1920s as breeders and U. S. Experiment Station researchers began to create Bos taurus taurus × Bos taurus indicus hybrids using Brahman as the B. t. indicus source. By 1954, U.S. Breed Associations had been formed for Brangus (5/8 Angus × 3/8 Brahman), Beefmaster (½ Brahman × ¼ Shorthorn × ¼ Hereford), and Santa Gertrudis (5/8 Shorthorn × 3/8 Brahman). While these breeds were developed using mating designs expected to create base generation animals with the required genome contributions from progenitor breeds, each association has now registered advanced generation animals in which selection or drift may have caused the realized genome compositions to differ from initial expected proportions. The availability of high-density SNP genotypes for 9,161 Brangus, 3,762 Beefmaster, and 1,942 Santa Gertrudis animals allowed us to compare the realized genomic architectures of breed members to the base generation expectations. We used RFMix to estimate local ancestry and identify genomic regions in which the proportion of Brahman ancestry differed significantly from a priori expectations. For all three breeds, lower than expected levels of Brahman composition were found genome-wide, particularly in early-generation animals where we demonstrate that selection on beef production traits was likely responsible for the taurine enrichment. Using a proxy for generation number, we also contrasted the genomes of early- and advanced-generation animals and found that the indicine composition of the genome has increased with generation number likely due to selection on adaptive traits. Many of the most-highly differentiated genomic regions were breed specific, suggesting that differences in breeding objectives and selection intensities exist between the breeds. Global ancestry estimation is commonly performed in admixed animals to control for stratification in association studies. However, local ancestry estimation provides the opportunity to investigate the evolution of specific chromosomal segments and estimate haplotype effects on trait variation in admixed individuals. Investigating the genomic architecture of the American Breeds not only allows the estimation of indicine and taurine genome proportions genome-wide, but also the locations within the genome where either taurine or indicine alleles confer a selective advantage.
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Jonsson, Nicholas N., David K. Cox, Emily K. Piper, Emily F. Mantilla Valdivieso, Constantin Constantinoiu, Louise A. Jackson, Michael J. Stear, Elizabeth M. Ross, and Ala E. Tabor. "Allelic Variation in Protein Tyrosine Phosphatase Receptor Type-C in Cattle Influences Erythrocyte, Leukocyte and Humoral Responses to Infestation With the Cattle Tick Rhipicephalus australis." Frontiers in Immunology 12 (July 9, 2021). http://dx.doi.org/10.3389/fimmu.2021.675979.
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The protein tyrosine phosphatase receptor type-C (PTPRC) gene encodes the common leukocyte antigen (CD45) receptor. CD45 affects cell adhesion, migration, cytokine signalling, cell development, and activation state. Four families of the gene have been identified in cattle: a taurine group (Family 1), two indicine groups (Families 2 and 4) and an African “taurindicine” group (Family 3). Host resistance in cattle to infestation with ticks is moderately heritable and primarily manifests as prevention of attachment and feeding by larvae. This study was conducted to describe the effects of PTPRC genotype on immune-response phenotypes in cattle that display a variable immune responsiveness to ticks. Thirty tick-naïve Santa-Gertrudis cattle (a stabilized composite of 5/8 taurine and 3/8 indicine) were artificially infested with ticks weekly for 13 weeks and ranked according to their tick counts. Blood samples were taken from control and tick-challenged cattle immediately before, then at 21 d after infestation and each subsequent week for 9 weeks. Assays included erythrocyte profiles, white blood cell counts, the percentage of cellular subsets comprising the peripheral blood mononuclear cell (PBMC) population, and the ability of PBMC to recognize and proliferate in response to stimulation with tick antigens in vitro. The cattle were PTPRC genotyped using a RFLP assay that differentiated Family 1 and 3 together (220 bp), from Family 2 (462 bp), and from Family 4 (486 bp). The PTPRC allele frequencies were Family 1/3 = 0.34; Family 2 = 0.47; Family 4 = 0.19. There was no significant association between PTPRC genotype and tick count. Each copy of the Family 1/3 allele significantly decreased total leucocyte count (WCC) and CD8+ cells. Increasing dosage of Family 2 alleles significantly increased red blood cell count (RCC), haematocrit (PCV), and haemoglobin (Hb) concentration in blood. Increasing dosage of the Family 4 allele was associated with increased WCC, reduced RCC, reduced PCV and reduced Hb. Homozygote Family 1/3 animals had consistently lower IgG1 in response to tick Ag than homozygote Family 2 animals. The PTPRC genotype influences the bovine immune response to ticks but was not associated with the observed variation in resistance to tick infestation in this study.
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Feuz, R., C. C. Reichhardt, R. Larsen, K. J. Thornton, and M. D. Garcia. "Comparing net returns in the feedlot: Bos Taurus vs. Bos Indicus influenced steers with varying anabolic implant intensity." Translational Animal Science, August 21, 2022. http://dx.doi.org/10.1093/tas/txac111.
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Abstract There are two main beef cattle breed types: Bos Taurus (BT) and Bos Indicus (BI). Past research has demonstrated various expected differences in growth, temperament, feeding behavior, and carcass characteristics between these breed types when administered varying levels of anabolic implant. However, little is known about the differences in expected economic returns between these cattle types. The objective of this research is to simulate and compare the expected net returns of BT, Angus (AN) steers and BI influenced, Santa Gertrudis (SG) steers, with moderate or high intensity levels of implants relative to a control with no implant. The animal performance and carcass data for this economic analysis was provided from a recent feeding experiment of AN and SG influenced steers. In the experiment, sixty steers were stratified by weight and breed in a 2 x 3 factorial design examining the two different breeds: AN (n=38) or SG influenced (n=22), and three implant strategies: no implant (n=20), a moderate intensity implant protocol (d0 implant: Revalor-G, d56 implant: Revalor-IS, d112 implant: Revalor-S; n=20), or a high intensity implant protocol (d0 implant: Revalor-IS, d56 implant: Revalor-S, d112 implant: Revalor-200; n=20). The steers performance and carcass data were used together with publicly available price and input costs data in the simulation of net returns per animal for each of the treatment groups. Results demonstrated that both moderate and high intensity implanted BT steers have higher expected net return ($78.70/hd. and $75.84/hd. respectively) compared to BI moderate and high intensity implanted steers ($47.03/hd. and $6.98/hd. respectively). Stochastic efficiency analysis with respect to a function demonstrated when certainty equivalent values are constrained to those ≥$0, only the moderate implanted BT steers would be included in the efficient set.
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Reichhardt, Caleb C., Chandler D. Stafford, Jocelyn M. Cuthbert, David S. Dang, Laura A. Motsinger, Mackenzie J. Taylor, Reganne K. Briggs, et al. "Cattle breed type and anabolic implants impact calpastatin expression and abundance of mRNA associated with protein turnover in the longissimus thoracis of feedlot steers." Journal of Animal Science 100, no. 8 (August 1, 2022). http://dx.doi.org/10.1093/jas/skac204.
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Abstract Two methods that the beef cattle industry can use to improve efficiency, sustainability, and economic viability are growth promotants and crossbreeding cattle of different breed types. In the United States, over 90% of cattle receive an anabolic implant at some point during production resulting in an overall increase in skeletal muscle growth. Recent research suggests that the two main cattle breed types, Bos indicus and Bos taurus, respond differently to anabolic implants. The objective of this study was to characterize changes that occur in skeletal muscle following implanting in Bos indicus influenced steers or Bos taurus steers. Twenty steers were stratified by initial weight in a 2 × 2 factorial design examining two different breeds: Angus (AN; n = 10) or Santa Gertrudis influenced (SG; n = 10), and two implant strategies: no implant (CON; n = 10) or a combined implant containing 120 mg TBA and 24 mg E2 (IMP; n = 10; Revalor-S, Merck Animal Health). Skeletal muscle biopsies were taken from the longissimus thoracis (LT) 2 and 10 d post-implantation. The mRNA abundance of 24 genes associated with skeletal muscle growth were examined, as well as the protein expression of µ-calpain and calpastatin. Succinate dehydrogenase mRNA abundance was impacted (P = 0.05) by a breed × treatment interaction 2 d post-implanting, with SG-CON having a greater increased abundance than all other steers. A tendency for a breed × treatment interaction was observed for calpain-6 mRNA (P = 0.07), with SG-CON having greater abundance than AN-CON and SG-IMP. Additionally, calpastatin protein expression was altered (P = 0.01) by a breed × treatment interaction, with SG-CON and SG-IMP steers having increased expression (P = 0.01) compared with AN-CON steers. At 2 d post-implanting, a breed × treatment interaction was observed with SG-CON steers having greater (P = 0.05) mRNA abundance of mitogen-activated protein kinase compared with AN-CON steers. Furthermore, breed affected (P = 0.05) calpastatin abundance with AN steers having increased (P = 0.05) abundance 2 d post-implanting compared with SG steers. Meanwhile, implants tended to affect (P = 0.09) muscle RING finger protein-1 mRNA abundance, with CON steers having increased (P = 0.09) abundance compared with that of IMP steers. These findings suggest that cattle breed type and anabolic implants impact calpastatin expression and mRNA abundance associated with protein turnover in the LT of feedlot steers 2 and 10 d post-implantation.
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Zimmermann, Madeline J., Larry A. Kuehn, Matthew L. Spangler, R. Mark Thallman, Warren M. Snelling, and Ronald M. Lewis. "Breed and heterotic effects for mature weight in beef cattle." Journal of Animal Science 99, no. 8 (July 14, 2021). http://dx.doi.org/10.1093/jas/skab209.
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Abstract Cow mature weight (MWT) is heritable and affects the costs and efficiency of a breeding operation. Cow weight is also influenced by the environment, and the relationship between the size and profitability of a cow varies depending on production system. Producers, therefore, need tools to incorporate MWT in their selection of cattle breeds and herd replacements. The objective of this study was to estimate breed and heterotic effects for MWT using weight-age data on crossbred cows. Cow’s MWT at 6 yr was predicted from the estimated parameter values—asymptotic weight and maturation constant (k)—from the fit of the Brody function to their individual data. Values were obtained for 5,156 crossbred cows from the U.S. Meat Animal Research Center (USMARC) Germplasm Evaluation Program using 108,957 weight records collected from approximately weaning up to 6 yr of age. The cows were produced from crosses among 18 beef breeds. A bivariate animal model was fitted to the MWT and k obtained for each cow. The fixed effects were birth year-season contemporary group and covariates of direct and maternal breed fractions, direct and maternal heterosis, and age at final weighing. The random effects were direct additive and residual. A maternal additive random effect was also fitted for k. In a separate analysis from that used to estimate breed effects and (co)variances, cow MWT was regressed on sire yearling weight (YWT) Expected Progeny Differences by its addition as a covariate to the animal model fitted for MWT. That regression coefficient was then used to adjust breed solutions for sire selection in the USMARC herd. Direct heterosis was 15.3 ± 2.6 kg for MWT and 0.000118 ± 0.000029 d−1 for k. Maternal heterosis was −5.7 ± 3.0 kg for MWT and 0.000130 ± 0.000035 d−1 for k. Direct additive heritabilities were 0.56 ± 0.03 for MWT and 0.23 ± 0.03 for k. The maternal additive heritability for k was 0.11 ± 0.02. The direct additive correlation between MWT and k was negligible (0.08 ± 0.09). Adjusted for sire sampling, Angus was heaviest at maturity of the breeds compared. Deviations from Angus ranged from −8.9 kg (Charolais) to −136.7 kg (Braunvieh). Ordered by decreasing MWT, the breeds ranked Angus, Charolais, Hereford, Brahman, Salers, Santa Gertrudis, Simmental, Maine Anjou, Limousin, Red Angus, Brangus, Chiangus, Shorthorn, Gelbvieh, Beefmaster, and Braunvieh. These breed effects for MWT can inform breeding programs where cow size is considered a key component of the overall profitability.