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Simple Summary: This study aimed to compare and analyze the metabolic differences in perirenal adipose tissue between Angus cattle and Chinese Simmental cattle. The results showed that the perirenal fat of Angus cattle had a larger cell area and stronger lipid deposition ability than that of Chinese Simmental cattle. Subsequently, 12 metabolites that may cause differences were screened out by liquid chromatography–tandem mass spectrometry technology. This study provides some basic data for further understanding the metabolic pattern of perirenal fat. The aim of this experiment was to investigate the differences in metabolites in perirenal fat (PF) between Chinese Simmental cattle and Angus cattle. Six healthy 18-month-old male Angus cattle and Chinese Simmental cattle were selected, and the perirenal adipose tissue was collected after slaughtering. HE staining, a triglyceride assay kit, and liquid chromatography–tandem mass spectrometry (LC-MS/MS) technology were used to compare and analyze the differences in the cell morphology, lipid accumulation, and metabolites of the two types of PF. The results showed that the PF of Angus cattle had a larger cell area and stronger lipid deposition ability than that of Simmental cattle. A total of 567 metabolites were detected by LC-MS/MS technology, of which 119 were significantly upregulated in Angus cattle PF and 129 were significantly upregulated in Simmental cattle PF. Differential metabolites were enriched in pathways such as fatty acid biosynthesis, polyunsaturated fatty acid biosynthesis, regulation of adipocyte lipolysis, and oxidative phosphorylation. Finally, 12 metabolites that may cause phenotypic differences between the two types of perirenal adipose tissue were screened out from these pathways. This study has preliminarily screened out biomarkers that may affect lipid metabolism in PF, providing basic data for the further exploration of the metabolic characteristics of PF. [ABSTRACT FROM AUTHOR]

The purpose of this experiment was to explore the effect of cross between Dashishan district cattle and different foreign excellent beef cattle breeds, so as to improve the production performance and beef quality of Dashishan district cattle. Limousin, Charolais, and Angus frozen semen were used to improve Dashishan district cow, and the reproductive performance of cows, fattening performance of calves and beef quality were measured. The results showed that the conception rate, calving rate, calving number, and calf survival number in Limousin group were significantly higher than those in Angus group and Charolais group (P<0.05), while the abortion rate was significantly lower than that in other hybrid groups (P<0.05). The birth weight, body weight at the end of each stage, weight gain at each stage, average daily gain from six months of age to slaughter, average daily gain at the whole stage, total feed intake, and average daily feed intake of F1 generation of the three hybrid groups were extremely higher than those of Dashishan group (P<0.01). The slaughter weight of Limousin group at 24 months was significantly higher than that of other hybrid groups (P<0.05). The live weight, carcass weight, and net meat weight before slaughter of the three hybrid groups were extremely higher than those of Dashishan group (P<0.01), among which Limousin group was the highest. The slaughter rate and net meat rate of Limousin group were significantly higher than those of Angus group and Dashishan group (P<0.05), and the carcass meat yield was slightly higher than that of other experimental groups (P>0.05). Crude fat content and marbling in Angus group were significantly higher than those in other groups (P<0.05). Sixteen amino acids and fifteen fatty acids were detected in each group. In the non-essential amino acids (NEAA), the contents of aspartate and serine in Dashishan group were significantly lower than those in other groups (P<0.05). There was no significant difference in the contentrations of essential amino acids (EAA), various fatty acids, saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA) in each group (P>0.05). The study indicates that Limousin group is superior to the other two hybrid combinations in reproductive performance, growth and finishing performance, and slaughtering performance, and Angus group is better in beef quality. [ABSTRACT FROM AUTHOR]

Simple Summary: Virtual fencing is an alternative to the ubiquitously used physical fences. It uses GPS to determine the location of livestock relative to a virtual line. The system deters livestock from leaving the enclosure by using an auditory warning followed by an electric impulse during approach and crossing of the fence line. This paper assessed the social effects on learning between cattle with and without prior experience with virtual fencing through three case studies: one with a gradual and two with an instant introduction method. These were applied to assess if improvements in associative learning could be made. Due to the non-standardised experiments, it was not possible to analyse the effect across the case studies and therefore to conclude whether the number of experienced cattle or the different introduction methods influenced the inexperienced cattle. Agricultural industries rely on physical fences to manage livestock. However, these present practical, financial, and ecological challenges, which may be solved using virtual fencing. This study aimed to identify how experienced cattle through social facilitation and the introduction method influence inexperienced cattle. Based on three stocks held in Fanø, Denmark, containing 12, 17 and 13 Angus (Bos taurus), we examined the virtual fence learning in three case studies using one gradual introduction with zero experienced cattle (A) and two different instant introductions with one (B) and ten (C) experienced cattle. Gradual introduction had the virtual fence moved 20 m every other day for eleven days, and in the two instant introductions, the physical fence was removed in one day. Warnings and impulses were recorded during an 11-day learning period and a 26-day post-learning period, using the impulses per warning to quantify if the cattle adapted. Case studies A and B showed a significant reduction in the warnings and impulses, but only A showed a significant reduction in the impulses per warning when comparing the learning period to the post-learning period. Due to the non-standardised experiments, it was not possible to conclude if the number of experienced cattle or the introduction method had an effect on the results. [ABSTRACT FROM AUTHOR]

Objective: This study aims to investigate the genetic structure and characteristics of the Angus cattle population in Hungary. The survey was performed with the assistance of the Hungarian Hereford, Angus, Galloway Association (HHAGA). Methods: Genetic parameters of 1,369 animals from 16 Angus herds were analyzed using the genotyping results of 12 microsatellite markers with the aid of PowerMarker, Genalex, GDA-NT2021, and STRUCTURE software. Genotyping of DNA was performed using an automated genetic analyzer. Based on pairwise identity by state values of animals, the Python networkx 2.3 library was used for network analysis of the breed and to identify the central animals. Results: The observed numbers of alleles on the 12 loci under investigation ranged from 11 to 18. The average effective number of alleles was 3.201. The overall expected heterozygosity was 0.659 and the observed heterozygosity was 0.710. Four groups were detected among the 16 Angus herds. The breeders' information validated the grouping results and facilitated the comparison of birth weight, age at first calving, number of calves born and productive lifespan data between the four groups, revealing significant differences. We identified the central animals/herd of the Angus population in Hungary. The match of our group descriptions with the phenotypic data provided by the breeders further underscores the value of cooperation between breeders and researchers. Conclusion: The observation that significant differences in the measured traits occurred among the identified groups paves the way to further enhancement of breeding efficiency. Our findings have the potential to aid the development of new breeding strategies and help breeders keep the Angus populations in Hungary under genetic supervision. Based on our results the efficient use of an upcoming genomic selection can, in some cases, significantly improve birth weight, age at first calving, number of calves born and the productive lifespan of animals. [ABSTRACT FROM AUTHOR]

The aim of this experiment is to investigate the composition and relative abundance of microbial species in the gastrointestinal tract of beef cattle associated with different residual feed intake (RFI), and the functional annotation and enrichment characteristics of microbial genes. Thirty cattle were selected for the 81-day feeding experiment, and at the end of the experiment, five individuals each with extreme RFI were selected for slaughter, and rumen fluid and intestinal end fecal samples were collected for macrogenome sequencing. The results showed that a total of 259 045.47 Mb valid data were obtained, 4 318 393 Scaftigs were assembled, and 7 008 053 open reading frames (ORFs) were obtained from gene prediction. Species annotation revealed no difference in the relative abundance of Top 10 species in the fecal samples between High Residual Feed Intake (HRFI) and Low Residual Feed Intake (LRFI) groups (P>0.05), and the relative abundance of Top 10 microorganisms in the rumen fluid in the LRFI group was lower than in the HRFI group; the dominant phylum in both feces and rumen fluid was the phylum Bacillus and the thick-walled phylum; the dominant genus in the feces was Bacteroides and the dominant genus in the rumen fluid was Prevotella. LefSe analysis showed a significant enrichment of Erysipelotrichia in the feces in the LRFI group (P<0.05), the most significant difference in rumen fluid was in the Methanobacterium class, and the relative abundance of this organism in the HRFI group was significantly higher than in the LRFI group (P<0.05). Functional annotation analysis using the KEGG, eggNOG and CAZy databases showed that the abundances of some functional genes of microorganisms in the gastrointestinal tract was associated with the grouping of RFI. In conclusion, the microbial structures in the rumen fluid and feces of beef cattle with different RFI varied significantly, and the Erysipelotrichia and Methanobacterium phyla may be among the potential biomarkers for differentiating feed efficiency in beef cattle. [ABSTRACT FROM AUTHOR]

The experiment was to study the effect of different forage ratio on growth and development, carcass trait and meat quality of Angus cattle. A total of 64 healthy six-month-old Angus cattle (half bulls and half cows) with similar body weight were randomly divided into four groups with four replicates in each group and four cattle in each replicate. Each group cattle was fed a total mixed diet with different forage proportions. The pre-test lasted for 15 d and the formal test lasted for 360 d. The results showed that the body weight of bull and cow in group 1 was significantly higher than that in group 3 and control group at 12 and 18-month-old (P<0.05), the body weight of bull in group 2 was significantly higher than that in group 3 and control group at 12 and 18-month-old (P<0.05), and that in group 2 was significantly higher than that in group 3 and control group at 18-month-old. Average daily gain of bulls and cows in group 1 was significantly higher than that in control group and group 3 at 7~12-month-old (P<0.05), average daily gain of bulls and cows in group 1 was significantly higher than that in group 3 at 13~18-month-old (P<0.05), average daily gain of bulls and cows in group 1 was significantly higher than that in group 3 at 7~18-month-old (P<0.05). The pre-slaughter weight, carcass weight and slaughter rate of bulls in group 1 were significantly higher than those in control group and group 3 (P<0.05), and the eye muscle area and back fat thickness of bulls in group 1 were significantly higher than those in other groups (P<0.05). Muscle and fat color in group 1 and group 2 were significantly lower than those in control group (P<0.05). The study indicates that the forage and feed ratio of group 1 is better for improving the growth and meat quality of Angus cattle. [ABSTRACT FROM AUTHOR]

Simple Summary: Grass-fed beef industry is booming in the USA. Compared to grain-fed, the rumen microbiome profiles and features in a grass-fed regimen have yet to be identified. In this study, we found that the rumen microbiome in the grass-fed cattle demonstrated greater species diversity and harbored significantly higher microbial alpha diversity than that of grain-fed cattle. The abundance of multiple unclassified genera, such as those belonging to Planctomycetes, LD1-PB3, SR1, Lachnospira, and Sutterella, were significantly enriched in the rumen of grass-fed steers. A rumen microbial predictor accurately distinguished the two feeding schemes. Multiple microbial signatures or balances strongly correlated with various levels of SCFA in the rumen. The results of this study provided deep insights into microbial interactions in the rumen under different feed schemes, which will help to develop rumen manipulation strategies to improve feed conversion ratios and average daily weight gains in beef practice. The health benefits of grass-fed beef are well documented. However, the rumen microbiome features in beef steers raised in a grass-fed regimen have yet to be identified. This study examined the rumen microbiome profile in the feeding regimes. Our findings show that the rumen microbiome of the grass-fed cattle demonstrated greater species diversity and harbored significantly higher microbial alpha diversity, including multiple species richness and evenness indices, than the grain-fed cattle. Global network analysis unveiled that grass-fed cattle's rumen microbial interaction networks had higher modularity, suggesting a more resilient and stable microbial community under this feeding regimen. Using the analysis of compositions of microbiomes with a bias correction (ANCOM-BC) algorithm, the abundance of multiple unclassified genera, such as those belonging to Planctomycetes, LD1-PB3, SR1, Lachnospira, and Sutterella, were significantly enriched in the rumen of grass-fed steers. Sutterella was also the critical genus able to distinguish the two feeding regimens by Random Forest. A rumen microbial predictor consisting of an unclassified genus in the candidate division SR1 (numerator) and an unclassified genus in the order Bacteroidales (denominator) accurately distinguished the two feeding schemes. Multiple microbial signatures or balances strongly correlated with various levels of SCFA in the rumen. For example, a balance represented by the log abundance ratio of Sutterella to Desulfovibrio was strongly associated with acetate-to-propionate proportions in the rumen (R2 = 0.87), which could be developed as a valuable biomarker for optimizing milk fat yield and cattle growth. Therefore, our findings provided novel insights into microbial interactions in the rumen under different feed schemes and their ecophysiological implications. These findings will help to develop rumen manipulation strategies to improve feed conversion ratios and average daily weight gains for grass- or pasture-fed cattle production. [ABSTRACT FROM AUTHOR]

Simple Summary: This study identified several variants and candidates with strong associations to coat color in Angus cattle by using genome sequencing data. In particular, the MC1R variants, which are a truncated MC1R protein obtained by altering the MCIR coding sequence region, result in lighter coat color and further enrich the genetic basis between DNA damage and melanin production caused. This study not only helped understand the hereditary basis of different coat colors, but also provided new ideas for future research on meat phenotypes. However, the putative candidate genes or markers identified in this study require further investigation to confirm their phenotypic causality and potential effective genetic relationships. Angus cattle have made remarkable contributions to the livestock industry worldwide as a commercial meat-type breed. Some evidence supported that Angus cattle with different coat colors have different feed-to-meat ratios, and the genetic basis of their coat color is inconclusive. Here, genome-wide association study was performed to investigate the genetic divergence of black and red Angus cattle with 63 public genome sequencing data. General linear model analysis was used to identify genomic regions with potential candidate variant/genes that contribute to coat color and feed conversion rate. Results showed that six single nucleotide polymorphisms (SNPs) and two insertion–deletions, which were annotated in five genes (ZCCHC14, ANKRD11, FANCA, MC1R, and LOC532875 [AFG3-like protein 1]), considerably diverged between black and red Angus cattle. The strongest associated loci, namely, missense mutation CHIR18_14705671 (c.296T > C) and frameshift mutation CHIR18_12999497 (c.310G>-), were located in MC1R. Three consecutive strongly associated SNPs were also identified and located in FANCA, which is widely involved in the Fanconi anemia pathway. Several SNPs of highly associated SNPs was notably enriched in ZCCHC14 and ANKRD11, which are related to myofiber growth and muscle development. This study provides a basis for the use of potential genetic markers to be used in future breeding programs to improve cattle selection in terms of coat color and meat phenotype. This study is also helpful to understand the hereditary basis of different coat colors and meat phenotypes. However, the putative candidate genes or markers identified in this study require further investigation to confirm their phenotypic causality and potential effective genetic relationships. [ABSTRACT FROM AUTHOR]

In this study, we explored the gene expression patterns of the pituitary gland and hypothalamus of Angus cows at different growth and developmental stages by deep sequencing and we identified genes that affect bovine reproductive performance to provide new ideas for improving bovine fertility in production practice. We selected three 6-month-old (weaning period), three 18-month-old (first mating period), and three 30-month-old (early postpartum) Angus cattle. The physiological status of the cows in each group was the same, and their body conformations were similar. After quality control of the sequencing, the transcriptome analyses of 18 samples yielded 129.18 GB of clean data. We detected 13,280 and 13,318 expressed genes in the pituitary gland and hypothalamus, respectively, and screened 35 and 50 differentially expressed genes (DEGs) for each, respectively. The differentially expressed genes in both tissues were mainly engaged in metabolism, lipid synthesis, and immune-related pathways in the 18-month-old cows as compared with the 6-month-old cows. The 30-month-old cows presented more regulated reproductive behavior, and pituitary CAMK4 was the main factor regulating the reproductive behavior during this period via the pathways for calcium signaling, longevity, oxytocin, and aldosterone synthesis and secretion. A variant calling analysis also was performed. The SNP inversions and conversions in each sample were counted according to the different base substitution methods. In all samples, most base substitutions were represented by substitutions between bases A and G, and the probability of base conversion exceeded 70%, far exceeding the transversion. Heterozygous SNP sites exceeded 37.68%. [ABSTRACT FROM AUTHOR]

The regulatory mechanisms controlling the ovary development in the Xiangxi cattle are still largely unknown, yet the growth and development of ovary is a complex process that plays a crucial role in reproduction. In this study, we performed a transcriptome analysis based on the RNA sequencing (RNA-Seq) of Xiangxi cattle and Angus cattle tissue obtained from 8 months of age to identify which genes are differentially expressed and to investigate their temporal expression profiles. The results showed that a total of 165 differential genes were annotated, of which 58 were annotated in the GO database and 73 were annotated in the KEGG database. A total of 12 comparatively concentrated signal pathways were obtained. Among them, the osteoclast differentiation signaling pathway (ko04380) was the most involved in differentially expressed genes. The other signaling pathways were amphetamine addiction, herpes simplex infection, caffeine metabolism, cocaine addiction, pertussis, ECM-receptor interaction, toll-like receptor signaling pathway, and glycosphingolipid biosynthesis - ganglio series. Functional analysis also showed that the differentially expressed genes were involved in various Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. GO annotations indicated that the genes related to biological processes, and molecular events were significantly active. KEGG pathway analysis showed that the osteoclast differentiation signaling pathway in Xiangxi ovary transcriptome data, at the end ECM-receptor interaction pathways. Moreover, several novel pathways, were significantly enriched despite having no evident associations with the reproductive function. Our findings provide a molecular resource for further investigation of the general molecular mechanism of Xiangxi cattle ovary and offer new insights to understand comprehensively the specificity of local cattle breeds reproduction. [ABSTRACT FROM AUTHOR]

Melatonin is an indoleamine, a neurotransmitter and neurohormone mainly produced in pineal gland but also in the ovary. It has an important role in reproduction, antioxidant, immune system and circadian behavior. Industrial hemp is increasingly being included in animal feeds and it is therefore important to evaluate the effect of industrial hemp supplementation on the profiles of melatonin following different phases of reproductive cycle. Twenty apparently healthy Angus heifers, aged 19 months with average body weight of 363 kg and body condition score of 6.5 were randomly divided into two groups of ten heifers each in a completely randomized design. Group 1 (n = 10) were supplemented with grounded industrial hemp at 20/200mg of the concentrate, and group 2 (n = 10) no industrial hemp supplementation. Hay and water were provided ad libitum. The animals were acclimatized for 1 week after which they were synchronized using the 7-day CO-Synch protocols. Salivary samples were collected at preestrus, during estrus and at post estrus. Melatonin in the saliva was assayed with a competitive ELISA kit. The salivary melatonin concentrations were greater (P > 0.05 in the treated groups at estrus (25.29 ± 1.48 pg/mL), pro-estrus (23.98 ± 2.3 pg/mL) and post-estrus (20.31 ± 3.0 pg/mL) compared with the untreated groups at pre-estrus (18.9 ± 1.5 pg/mL), estrus (20.4 ± 2.22 pg/mL) and post estrus (17.22 ± 2.6 pg/mL). The profiles of the salivary melatonin were greater (P > 0.05) at estrus phase in the hemp treated groups compared with the pre-estrus and post estrus phase of the treated groups; however, numerical but nonsignificant increases were observed in the untreated group at estrus phase compared with the pre-estrus and post estrus phases. It was concluded that industrial hemp supplementation could improve melatonin concentrations and hence improve reproductive, antioxidant and immune function of the cattle. [ABSTRACT FROM AUTHOR]

Summary: Bioeconomic models were developed to calculate economic values (EV) for economically important traits in beef cattle, to evaluate the impact of these traits on production profitability, to assess possible market changes with a payment system and to develop economic selection indexes for Angus cattle for two production systems. Two beef cattle production systems were simulated as follows: a cow‐calf cycle (CC) and a complete cycle (CoC). Following selection, positive changes in the EV were observed. In the CC, each 1.0% increment in weaning weight (WW), weaning rate (WR) and pregnancy rate (PR) resulted in increases in US$ 1.30, US$ 3.68 and US$ 3.55 per cow/year in profit, respectively. In the CoC, EV of US$ 1.01, US$ 1.79, US$ 1.19, US$ 1.34, US$ 6.84 and US$ 7.86 per cow/year were obtained for WW, year weight, yearling weight, final weight, WR and PR, respectively. The payment system for carcass quality showed that the scenario considering that 100% of the animals displayed uniform carcasses exhibited the highest EV and was considered optimal. Considering the sensitivity analysis, the price paid per animal was the factor that most affected the EV in both systems. The selection indexes obtained may be used in similar production systems, and the use of EV and selection indexes are important tools for any production system with positive change in profit after selection. [ABSTRACT FROM AUTHOR]

Pulmonary arterial pressure (PAP) is an indicator trait for pulmonary hypertension and for the risk of developing high-altitude disease (HAD) in cattle. Pulmonary arterial pressures provide a tool for selection of breeding cattle for tolerance to high altitude in mountainous regions of the United States. The objective of this study was to evaluate relationships between growth performance traits and yearling PAP (42.4 ± 9.9 mmHg; n = 5,776; elevation 2,150 m) using data from 1993 to 2014 in the John E. Rouse Colorado State University Beef Improvement Center (CSU-BIC) Angus herd. The breeding program used sires (n = 299) from both low- and high-elevation environments. We hypothesized that little to no genetic relationship exists between PAP and birth weight (BWT; direct and maternal), weaning weight (WW; direct and maternal), yearling weight (YW; direct and maternal), and postweaning gain (PWG). Historic selection of natural service sires from within the herd required a PAP of ≤ 42 mmHg. Outside AI sires (n = 156) used in this breeding program were not PAP tested and therefore were used with little knowledge of these sires’ high-altitude adaptability. Performance traits (± SD) routinely recorded included BWT (36.2 ± 5.1 kg; n = 8,695), WW (213.5 ± 31.8 kg; n = 8,010), YW (345.6 ± 83.8 kg; n = 5,580), and PWG (122.0 ± 63.7 kg; n = 5,449), where PWG represented the total weight gained from weaning to yearling age. Four-trait analyses using REML were conducted with an animal model. The heritability estimates (± SE) for PAP (0.26 ± 0.03), BWT direct (0.42 ± 0.04) and maternal (0.14 ± 0.02), WW direct (0.29 ± 0.04) and maternal (0.19 ± 0.03), YW direct (0.45 ± 0.04) and maternal (0.23 ± 0.03), and PWG (0.14 ± 0.02) were in the range of those reported in previous literature. Estimates of genetic correlations (± SE) revealed weak relationships between PAP and direct and maternal BWT, direct and maternal WW, direct and maternal YW, and PWG of 0.15 ± 0.09, 0.14 ± 0.10, 0.23 ± 0.09, −0.01 ± 0.10, 0.12 ± 0.08, 0.00 ± 0.09, and −0.10 ± 0.10, respectively. The results of this study suggest that selection for lower PAP measures should have minimal influence on the growth performance of yearling Angus bulls and heifers at the CSU-BIC, supporting our hypothesis. [ABSTRACT FROM AUTHOR]

Advances in genomics, molecular biology, and statistical genetics have created a paradigm shift in the way livestock producers pursue genetic improvement in their herds. The nexus of these technologies has resulted in combining genotypic and phenotypic information to compute genomically enhanced measures of genetic merit of individual animals. However, large numbers of genotyped and phenotyped animals are required to produce robust estimates of the effects of SNP that are summed together to generate direct genomic breeding values (DGV). Data on 11,756 Angus animals genotyped with the Illumina BovineSNP50 Beadchip were used to develop genomic predictions for 17 traits reported by the American Angus Association through Angus Genetics Inc. in their National Cattle Evaluation program. Marker effects were computed using a 5-fold cross-validation approach and a Bayesian model averaging algorithm. The accuracies were examined with EBV and deregressed EBV (DEBV) response variables and with K-means and identical by state (IBS)-based cross-validation methodologies. The cross-validation accuracies obtained using EBV response variables were consistently greater than those obtained using DEBV (average correlations were 0.64 vs. 0.57). The accuracies obtained using K-means cross-validation were consistently smaller than accuracies obtained with the IBS-based cross-validation approach (average correlations were 0.58 vs. 0.64 with EBV used as a response variable). Comparing the results from the current study with the results from a similar study consisting of only 2,253 records indicated that larger training population size resulted in higher accuracies in validation animals and explained on average 18% (69% improvement) additional genetic variance across all traits. [ABSTRACT FROM AUTHOR]

The pedigree chart is a cornerstone technology for producing bodies and value in livestock pure breeding. It organizes a cluster of processes, technologies, and discourses gathered under the rubric ‘pedigree practices’. Angus breeders commonly use artificial insemination to import performance ‘genetics’ into their herds, using the ‘expected progeny differences’ predicted by massive pedigree databases that now also contain phenotype data reported by cattle growers. Discourses of biological inheritance, good breeding, and pedigrees arose in the eighteenth century, concomitant with a fascination with races, species, and other biological kinds. A case study from Angus cattle breeding illustrates pedigree practices and the bodies made through them, showing how information and computing technologies, assisted reproductive technologies, and discourses of good breeding, purity, health, and disease leveraged a single bull and the two genetic diseases he carried into the pedigrees of up to 10% of the Angus herd. Technologies now widely used in human reproductive medicine were developed for use in livestock animals, especially cattle, extending a long relationship between cows and humans. While the development of these pedigree practices represents increased control over animal reproduction and bodies, it has also been instrumental in rendering all animal bodies, including human bodies, not only more technically but also more rhetorically available for reproductive interventions. These interventions may amplify anxieties about health, species, breed, and kin while also providing opportunities for contesting the boundaries of these nature–cultural categories. [ABSTRACT FROM AUTHOR]

Abstract: A study was conducted to compare cholesterol and fatty acid levels of beef from three cattle breeds raised on natural pasture. Thirty-four, twenty-nine and fourteen steers each of Nguni, Bonsmara and Angus, respectively, were slaughtered at 18 months. There were no (P >0.05) breed differences for the cholesterol and intramuscular fat (IMF) levels. The fatty acid profiles were similar (P >0.05) among the three breeds except that beef from Nguni steers had higher (P <0.05) docosahexaenoic acid content than beef from the other two breeds while beef from Bonsmara steers had the highest (P <0.05) heptadacenoic acid content. It can be concluded that there were no breed differences on cholesterol and most fatty acids. [Copyright &y& Elsevier]

• Means of metabolic heat production were 2.24 W kg−1 for crossbred and 1.09 W kg−1 for Nellore. • The rectal temperature oscillated 0.6°C for the crossbred and 0.3°C for the Nellore. • The heat storage was higher for crossbred cattle. • Crossbred cattle maintained their thermal balance with high cutaneous evaporation. In this study we compared the bio-thermal responses of a crossbred (F1, Nellore x Angus) and purebred Bos indicus (Nellore) cattle kept under moderate thermal conditions. Specifically, we assessed if they were different in their daily pattern of metabolic heat production, regulation of body temperature and use of evaporative heat transfer pathways. Six Nellore bulls with 669 ± 65 kg of body weight and twelve crossbred bulls (F1, Nellore x Angus) with 606.5 ± 25.09 kg of body weight, were evaluated in two experiments. Individual bulls were secured and attached to instruments in the biometeorology laboratory to enable recording of the proportion of respiratory gases in the exhaled air (oxygen, O 2 ; carbon dioxide, CO 2), saturation pressure of the exhaled air (P S {T EXP }, kPa) and skin surface (P S {T SKIN }, kPa), respiratory rate (R R , breath min−1), ventilation rate (V E , L s−1); skin (T SKIN ,°C), hair coat (T S ,°C), rectal (T R ,°C) and exhaled air temperatures (T EXP ,°C) from 0600 to 1800 h. The air temperature over the two experiments ranged from 16 to 30°C. The mean of metabolic heat production was higher for crossbred (2.24 W kg−1) than Nellore cattle (1.09 W kg−1) (P <0.0001), as the crossbred had higher values ​​for ventilation rate (P <0.0001), and proportion of the oxygen extracted from the inhaled air. Slight differences for thermal storage and daily fluctuation of daytime rectal temperature (0730 and 1630 h) were also observed, ranging from 39 to 39.30°C for Nellore cattle and from 39.12 to 39.62°C for the crossbred. Both genotypes increased heat loss through cutaneous evaporation with rising air temperature, which was slightly higher for the crossbred cattle. In conclusion, under the moderate thermal conditions of the present study, the crossbred cattle had higher levels of heat production, thermal storage and cutaneous evaporation than the purebred Nellore cattle. Further, it appears that both genotypes were able to maintain their thermal balance with relatively low energy demand for thermoregulation. [ABSTRACT FROM AUTHOR]