Seasonal fluctuations in plasma concentrations of luteinizing hormone and progesterone in Brahman (Bos indicus) and Hereford-Shorthorn (Bos taurus) cows grazing pastures at two stocking rates in a subtropical environment

Abstract To evaluate how the inclusion of Bos indicus genotype influences early fetal development in cattle, a reciprocal embryo transfer approach was used in a completely randomized design with a 2×2×2 factorial arrangement of treatments in order to generate 55 pregnancies (n = 55). Recipient cows were randomly assigned to 1) a diet that met daily energy maintenance requirements (MAINT), or 2) a diet that restricted intake to 70% of the energy maintenance requirements (RESTR). Angus (AN) and Brangus (BN) embryo donors were superovulated and artificially inseminated with female sexed-sorted semen from the same breed. Embryos were then randomly transferred to either AN or BN recipients fed their respective diets for 28d. Recipients remained on the dietary scheme until d91 of gestation, and were then comingled and fed a common diet that met their requirements. Measurements included pregnancy establishment at d28 of gestation, pregnancy-associated glycoproteins (PAG; using 2 commercial [A1 and A2] and 1 in-house assay), and fetal size (CRL). Recipients in the RESTR diet had lower BW and BCS (diet×day; P < 0.01) than MAINT recipients. Energy-restricted AN recipients experienced greater (recipient breed×diet, P < 0.01) pregnancy failure by d28 than the other recipient breed × diet combinations. Restricted recipients that received AN embryos experienced greater pregnancy failure than RESTR recipients receiving BN embryos (embryo breed×diet; P = 0.03). Brangus embryos resulted in greater plasma concentrations of PAG in both A1 (embryo breed×day, P < 0.01) and A2 (embryo breed P < 0.01). Alternatively, recipients that received AN embryos had greater plasma concentrations of PAG for the in-house assay (embryo breed×day; P < 0.01). In addition, fetuses from AN recipients had greater CRL on d91 (breed×day, P < 0.01). In summary, Bos taurus cows experienced greater pregnancy failure when nutrient restricted. Furthermore, fetal size and profile of PAG production during early gestation differed between Bos indicus-influenced and Bos taurus cattle.

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Reduction of energy requirements of steers fed on low-quality-roughage diets using trenbolone acetate

British Journal Of Nutrition ◽

10.1079/bjn19870115 ◽

1987 ◽

Vol 58 (3) ◽

pp. 477-483 ◽

Cited By ~ 25

Author(s):

R. A. Hunter ◽

J. E. Vercoe

Keyword(s):

Metabolic Rate ◽

Bos Taurus ◽

Plasma Concentrations ◽

Bos Indicus ◽

Live Weight ◽

Lower Plasma ◽

Trenbolone Acetate ◽

Low Protein ◽

Experiment Control ◽

The Difference

1. Six steers implanted with 300 mg trenbolone acetate and six steers not implanted were fed on low protein, low-quality-roughage dietsad lib.in two experiments. The steers were Hereford (Bos taurus) × Brahman (Bos indicus) crossbreds (50:50), initially of about 400 kg mean live weight (LW). In the first experiment of 8 weeks duration roughage was given alone. In the second experiment of 6 weeks duration the diet was supplemented with 100 g urea and 4.6 g sulphur daily. The same steers were implanted in each experiment. At the conclusion of each experiment metabolic rate was measured after a 72 h fast.2. In the first experiment control and implanted steers had similar rates of LW loss (0.57 and 0.59 kg/d respectively). Implanted steers had significantly (P < 0.01) lower feed intakes (12.8v.10.9 g dry matter (DM)/kg LW), significantly (P < 0.01) lower fasting metabolic rates even after adjustment for intake (83.3v. 74.5 kJ/kg per d) and significantly (P < 0.01) lower plasma insulin concentrations (24v.19 μunits/ml). Differences in plasma concentrations of free 3,5,3′-triiodothyronine (T3), non-esterified fatty acids and urea-nitrogen were not significant.3. In the second experiment intake of the supplement diet was similar in both control and trenbolene acetate treated steers (19.5 and 20.0 g DM/kg LW respectively). LW gains were 0.23 and 0.41 kg/d for control and implanted steers respectively, the difference being s ignificant (P < 0.05). Fasting metabolic rate (76.9v.70.7 kJ/kg per d) was significantly (P < 0.05) lower in implanted steers.

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Genome-wide identification of cyclin-dependent kinase (CDK) genes affecting adipocyte differentiation in cattle

BMC Genomics ◽

10.1186/s12864-021-07653-8 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Cuili Pan ◽

Zhaoxiong Lei ◽

Shuzhe Wang ◽

Xingping Wang ◽

Dawei Wei ◽

...

Keyword(s):

Gene Family ◽

Expression Analysis ◽

Adipocyte Differentiation ◽

Bos Taurus ◽

Adipogenic Differentiation ◽

Critical Role ◽

Bos Indicus ◽

Specific Expression ◽

Genome Wide ◽

A Genome

Abstract Background Cyclin-dependent kinases (CDKs) are protein kinases regulating important cellular processes such as cell cycle and transcription. Many CDK genes also play a critical role during adipogenic differentiation, but the role of CDK gene family in regulating bovine adipocyte differentiation has not been studied. Therefore, the present study aims to characterize the CDK gene family in bovine and study their expression pattern during adipocyte differentiation. Results We performed a genome-wide analysis and identified a number of CDK genes in several bovine species. The CDK genes were classified into 8 subfamilies through phylogenetic analysis. We found that 25 bovine CDK genes were distributed in 16 different chromosomes. Collinearity analysis revealed that the CDK gene family in Bos taurus is homologous with Bos indicus, Hybrid-Bos taurus, Hybrid Bos indicus, Bos grunniens and Bubalus bubalis. Several CDK genes had higher expression levels in preadipocytes than in differentiated adipocytes, as shown by RNA-seq analysis and qPCR, suggesting a role in the growth of emerging lipid droplets. Conclusion In this research, 185 CDK genes were identified and grouped into eight distinct clades in Bovidae, showing extensively homology. Global expression analysis of different bovine tissues and specific expression analysis during adipocytes differentiation revealed CDK4, CDK7, CDK8, CDK9 and CDK14 may be involved in bovine adipocyte differentiation. The results provide a basis for further study to determine the roles of CDK gene family in regulating adipocyte differentiation, which is beneficial for beef quality improvement.

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Expression of candidate genes for residual feed intake in tropically adapted Bos taurus and Bos indicus bulls under thermoneutral and heat stress environmental conditions

Journal of Thermal Biology ◽

10.1016/j.jtherbio.2021.102998 ◽

2021 ◽

pp. 102998

Author(s):

Bianca Vilela Pires ◽

Nedenia Bonvino Stafuzza ◽

Luara Afonso de Freitas ◽

Maria Eugênia Zerlotti Mercadante ◽

Ester Silveira Ramos ◽

...

Keyword(s):

Heat Stress ◽

Candidate Genes ◽

Feed Intake ◽

Environmental Conditions ◽

Bos Taurus ◽

Bos Indicus ◽

Residual Feed Intake

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87 Evaluation of two stocking rates for grazing heifers on mixed sward native warm-season grass pastures in the Black Belt Prairie region

Journal of Animal Science ◽

10.1093/jas/skz397.061 ◽

2020 ◽

Vol 98 (Supplement_2) ◽

pp. 27-27

Author(s):

Jane A Parish ◽

Kalisha C Yankey ◽

Libby S Durst

Keyword(s):

Nutritive Value ◽

Bos Taurus ◽

Warm Season ◽

Stocking Rate ◽

Sorghastrum Nutans ◽

Study Objective ◽

Little Bluestem ◽

Year Effect ◽

Plant Persistence ◽

Stocking Rates

Abstract Optimal use of native warm-season grasses in pasture systems involves stocking grazing livestock at suitable rates. The study objective was to evaluate forage nutritive value and heifer ADG at two stocking rates on mixed-sward pastures of big bluestem (Andropogon gerardi Vitman), little bluestem (Andropogon scoparius), and indiangrass (Sorghastrum nutans L.). Pastures (3 replications) were stocked for 56 d during June and July in 2 yr with crossbred (Bos taurus) heifers (n = 24 heifers/year) stratified by initial BW (288.3 ± 1.7 kg) to one of two continuous stocking rates: 1.9 heifers/ha (HIGH) and 1.2 heifers/ha (LOW). Mean forage nutritive values on a DM basis were not different between HIGH and LOW stocking rates, respectively, for CP (7.0 ± 0.2% vs 6.7 ± 0.2%; P = 0.27), ADF (41.0 ± 0.6 vs. 41.4 ± 0.6; P = 0.64), NDF (69.9 ± 0.5 vs. 68.7 ± 0.5; P = 0.09), or relative feed value (RFV) (76.0 ± 1.0 vs. 76.9 ± 1.0; P = 0.53). There was a year effect (P < 0.01) and stocking rate x day effect (P < 0.01) for TDN. At LOW, TDN decreased from day 0 to day 28 (P = 0.02) and day 28 to day 56 (P = 0.02). At HIGH, TDN decreased (P < 0.01) from day 0 to day 28 but remained steady until day 56 (P = 0.21). There was a stocking rate x day interaction (P < 0.01) with ADG: LOW day 28 to 56 (1.20 ± 0.08 kg/day), HIGH day 0 to 28 (0.89 ± 0.08 kg/day), HIGH day 28 to 56 (0.44 ± 0.08 kg/day), and LOW day 0 to 28 (0.30 ± 0.08 kg/day). Further assessment of cattle ADG using more divergent stocking rates and plant persistence measures is warranted to inform ideal native grass stocking rate recommendations.

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Differences in copper and selenium metabolism between Angus (Bos taurus) and Brahman (Bos indicus) cattle

Journal of Animal Science ◽

10.1093/jas/skab048 ◽

2021 ◽

Author(s):

J Ranches ◽

R Alves ◽

M Vedovatto ◽

E Anne Palmer ◽

P Moriel ◽

...

Keyword(s):

Bos Taurus ◽

Bos Indicus ◽

First Trimester ◽

Beef Cows ◽

Experimental Unit ◽

University Of Florida ◽

Brahman Cattle ◽

Research And Education ◽

The University ◽

Se Status

Abstract A two-year study was conducted at the University of Florida – IFAS, Range Cattle Research and Education Center (Ona, FL) to evaluate differences in the metabolism of Cu and Se of Angus (Bos taurus) and Brahman (Bos indicus) cattle. Thirty-two pregnant beef cows (n = 8 Brahman and 8 Angus/year) were enrolled in the study in the first trimester of gestation. The study consisted of 3 phases: (1) restriction (d 0 to d 90); (2) supplementation (d 91 to 150), and (3) calving. During all 3 phases, cows were individually fed and housed in partially covered drylot pens. During the restriction and supplementation phases cows were provided a 1.5 kg/d of a grain-based concentrate supplement, which was fortified with flowers of S (50 g of supplemental S/cow daily; restriction phase) or Cu and Se (100 and 3 mg/d of Cu and Se, respectively; supplementation phase). Blood and liver samples were collected from all cows on 30 d intervals and from both cows and calves within 24 h of calving. Colostrum and milk samples were collected at calving and 7 d after birth. All data were analyzed using the MIXED procedure of SAS, where cow and calf were the experimental unit. During the restriction phase, a breed × day effect (P = 0.03) was observed where Brahman had greater liver Cu concentration than Angus cows in all sampling days. For liver Se concentration, a tendency (P = 0.07) for a breed effect was observed where Angus cows tended to have greater liver Se concentration than Brahman. During the supplementation phase, breed (P < 0.001) and day (P < 0.01) effects were observed, where Brahman cows had greater liver Cu concentration than Angus. For liver Se concentration, a day effect (P < 0.001) was observed, where liver Se concentration increased (P < 0.001) from d 90 to 120 and remained unchanged (P = 0.86) until d 150. At calving no effects of breed (P = 0.34) were observed for liver Cu concentration of cows, however, Brahman calves tended (P = 0.09) to have greater liver Cu concentration than Angus calves. For Se liver concentration at calving, Angus cows tended (P = 0.07) to have greater liver Se concentration than Brahman cows, however no breed differences (P = 0.70) were observed for liver Se concentration of calves at birth. In summary substantial differences in multiple indicators of Cu and Se status were observed between Angus and Brahman cattle, implying that Angus and Brahman cattle possibly have different mechanisms to maintain adequate Cu and Se status.

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