PSXII-19 Organ and cellular contributions to heat production in Brahman and Angus steers

Abstract Reductions in basal metabolism and growth rate appear to contribute to decreased heat production of Bos indicus breeds. Lower metabolic rate may be due to smaller organ size and lower metabolic activity. Liver and heart account for high percentage of metabolic activity relative to their weight, and at a cellular level, mitochondria are responsible for producing energy for cellular maintenance. Our objective was to determine liver and heart weight and evaluate expression of key mitochondrial proteins in Bos indicus (80–100% Brahman) and Bos taurus (80–100% Angus) steers. Steers (n = 14 per breed) were harvested at the university meat laboratory. After evisceration, livers and hearts were weighed, and samples were frozen in liquid nitrogen for further analyses. Western blotting was used to determine expression of proteins in mitochondrial energy production: citrate synthase, a marker of mitochondria content; succinate dehydrogenase B (SDH-B), complex II; cytochrome c oxidase subunit IV, complex IV; and ATP synthase subunit 5A (ATP5A), complex V. Data were analyzed using an unpaired t-test in SAS-JMP. Although steers were similar age at slaughter (P = 0.84), Brahman steers weighed less (P < 0.0001) and thus produced lighter carcasses (P < 0.0001) and smaller livers and hearts (P < 0.0001). On a relative basis (kg organ/kg BW), Brahman tended to possess smaller hearts (P = 0.06) and smaller livers (P = 0.03). Expression of mitochondria proteins in heart did not differ between breeds (P > 0.3). However, Brahman exhibited lower expression of SDH-B (P = 0.005) but tended to have higher expression of ATP5A (P = 0.07) in liver. Altogether, this supports that smaller organ size is a contributing factor to lower heat production in heat-tolerant Brahman steers, and shifts in mitochondria protein expression in liver may impact energy metabolism at the cellular level.

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The effects of genotype, age, pregnancy, lactation and rumen characteristics on voluntary intake of roughage diets by cattle

Australian Journal of Agricultural Research ◽

10.1071/ar9860549 ◽

1986 ◽

Vol 37 (5) ◽

pp. 549 ◽

Cited By ~ 21

Author(s):

RA Hunter ◽

BD Siebert

Keyword(s):

Bos Taurus ◽

Bos Indicus ◽

Late Pregnancy ◽

Poor Quality ◽

Heteropogon Contortus ◽

Lactating Cows ◽

Significant Difference ◽

Pregnancy And Lactation ◽

Rate Of Decline ◽

Brahman Steers

The effects of genotype, age and liveweight, pregnancy and lactation on the voluntary feed intake by cattle of roughage diets of different qualities were studied in a number of experiments. The diets ranged from poor quality (low-nitrogen, high-fibre) spear grass (Heteropogon contortus) hay on which intakes were low ( 1 1 g DM/kg liveweight (LW)) to good quality lucerne (Medicago sativa) hay (26 g DM/kg LW). On the poorest-quality diet, differences in intake between Bos taurus and Bos indicus were not significant. However, on the higher quality diets Herefords (Bos taurus) ate significantly (P < 0.05) more than Brahmans (Bos indicus). In addition, as the quality of the diet improved from speargrass through to lucerne, the breed difference in favour of the Herefords became progressively greater and the variability between animals progressively smaller as a proportion of intake. Another study showed that with increasing age and liveweight of steers, intake per unit body weight declined, the rate of decline being significantly (P < 0.05) greater on good-quality lucerne compared to a poor-quality speargrass diet. There was no significant difference between Aberdeen Angus (Bos taurus) and Brahman steers in the rate of decline of intake of each diet with increasing age and liveweight of the steers. Another experiment which measured intake of pregnant and lactating heifers showed that the amount of feed eaten by pregnant heifers increased with increasing liveweight in late pregnancy, with intake per unit liveweight remaining constant. Lactating cows ate 35% more on a liveweight basis than their nonpregnant, non-lactating counterparts. These results are discussed in relation to mechanisms which control intake of roughage diets in ruminants, especially those associated with energy metabolism.

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Thermosensitivity of Bos indicus cattle and their F1, crosses with three breeds of Bos taurus

Animal Science ◽

10.1017/s0003356100005687 ◽

1991 ◽

Vol 52 (1) ◽

pp. 57-65 ◽

Cited By ~ 7

Author(s):

Khub Singh ◽

N. K. Bhattacharyya

Keyword(s):

Ambient Temperature ◽

Rectal Temperature ◽

Heat Production ◽

Bos Taurus ◽

Bos Indicus ◽

Metabolizable Energy ◽

Ambient Temperatures ◽

Brown Swiss ◽

Genetic Groups ◽

Holstein Friesian

ABSTRACTResting heat production (H), respiratory rate (RR) and rectal temperature (Tr) were measured at different controlled temperatures (Tt) in Hariana (Bos indicus) and its F, crosses with Jersey (JH), Brown Swiss (BH) and Holstein Friesian (FH) (Bos taurus) breeds and the values obtained were used to assess their relative thermosensitivity.The lowest Tt at which H significantly decreased from that at 17°c was 32°c for Hariana, JH and BH and 27°c for FH after exposure for 8 days. The corresponding values after exposure for 18 days were 37°c for Hariana and 32°c for all the three crossbred groups. Differences between the genetic groups were also significant. The lowest Tt at which metabolizable energy (ME) decreased significantly in comparison with those at 17CC was 32°c in all the genetic groups. The differences in ME intake between genetic groups were significant only at 32°c Tt. The lowest Tt at which RR significantly increased from those at 17°c were 32°c in Hariana, 27°c in JH, BH and FH for both 5 to 7 and 15 to 17 days of exposure. The corresponding Tt for increase in Tr was 37°c in Hariana, 32°c in JH and 27°c in BH and FH at both 5 to 7 and 15 to 17 days of exposure.The ambient temperature at which H would have significantly decreased and RR and Tr increased from the respective values at 17CC Tt were calculated curvilinearly for different genetic groups. There were differences in these values of calculated ambient temperatures between genetic groups and between exposure durations in respect of H, RR, and Tr, indicating differences in thermosensitivity.

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The performance of Brahman-Shorthorn and Sahiwal-Shorthorn cattle in the dry tropics of northern Queensland. 4. Postweaning growth and carcass traits

Australian Journal of Experimental Agriculture ◽

10.1071/ea9930531 ◽

1993 ◽

Vol 33 (5) ◽

pp. 531 ◽

Cited By ~ 3

Author(s):

G Fordyce ◽

ID Loxton ◽

RG Holroyd ◽

RJ Mayer

Keyword(s):

Bos Taurus ◽

Bos Indicus ◽

Meat Processing ◽

Wet Season ◽

Average Growth ◽

Longissimus Dorsi Muscle ◽

Dry Seasons ◽

The Difference ◽

Breed Crosses ◽

Brahman Steers

Postweaning growth to slaughter at 42 months of age in males and to initial mating at 27 months of age in females was studied in 4 inter se mated Bos indicus crosses in a dry tropical environment. Six-monthly growth periods from weaning (at about 6 months of age) generally coincided with wet and dry seasons. The cattle represented were second and subsequent generations of 112 Brahman and 112 Sahiwal crosses and first backcross and later generations of 314 Brahman and 314 Sahiwal crosses, The Bos taurus component of the crosses was primarily Beef Shorthorn. Annual growth averaged 300 g/day, with annual gain ranging from 60 to 180 kg. Average growth rates were about 50 g/day in the dry season (-352 to +374 g/day) and 500 g/day in the wet season (221-830 g/day). Postweaning growth of Brahman crosses was about 4% higher than Sahiwal crosses, with most of this advantage expressed in wet seasons. Sahiwal crosses were earlier maturing than Brahman crosses. Wet season growth was higher in 314 crosses than in 1/2 crosses, which probably reflected significant environmental stress in this period. Higher growth of 3/4 crosses tended to be maintained during dry seasons. Calves born late in a wet season grew more rapidly in dry seasons than early-born calves, so that liveweight differences which were apparent at weaning were reduced by one-third at 24 months of age. The difference between liveweights of weaners with young dams and those with mature dams was also reduced from 12-18 kg to 5-6 kg by 24 months. Dressing percentages of 3/4 cross steers at slaughter were 0.6 units higher than in half crosses, with no difference between Brahman and Sahiwal crosses. Sarcomere lengths, Warner-Bratzler shear force values, and Instron compression values together showed that M. longissimus dorsi muscle samples from 1/2 Brahman steers were the most tender of the breed crosses studied. Samples from Sahiwal cross and 3/4 Brahman steers appeared most affected by connective tissue toughness. Those from 3/4 Sahiwals appeared most affected by meat processing factors, causing them to be the least tender.

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The development of a dynamic, mechanistic, thermal balance model for Bos indicus and Bos taurus

The Journal of Agricultural Science ◽

10.1017/s002185961300049x ◽

2013 ◽

Vol 152 (3) ◽

pp. 464-482 ◽

Cited By ~ 5

Author(s):

V. A. THOMPSON ◽

L. G. BARIONI ◽

T. R. RUMSEY ◽

J. G. FADEL ◽

R. D. SAINZ

Keyword(s):

Heat Stress ◽

Heat Production ◽

Bos Taurus ◽

Physiological Responses ◽

Bos Indicus ◽

The Body ◽

Current Paper ◽

Wave Radiation ◽

Heat Flows ◽

Body Core

SUMMARYThe dynamic model presented in the current paper estimates heat production and heat flow between growing and mature cattle (Bos indicus and Bos taurus) and the surrounding environment. Heat production was calculated using the NRC (2000) and heat flows between the animal and the environment were based largely on existing models and physical principles. Heat flows among the body core, the skin, the coat and the environment were calculated. Heat flows from and to the environment included solar radiation, long wave radiation, convection and evaporative heat loss. Physiological responses of cattle (sweating, panting and vasodilation) were modelled through mechanistic equations. The model required weather (radiation, temperature, wind and vapour pressure), animal (body-core weight and genotype-specific parameters) and dietary inputs (dry matter intake rates and diet composition) and estimated heat balance and the physiological responses of the animal to within-day weather variation. The current paper has focused on heat stress, although the model was designed to run under both hot and cold climatic conditions. The model developed in the current paper provides researchers and livestock producers with the ability to predict heat stress and to evaluate mitigating procedures.

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Utilization of low-quality roughage by Bos taurus and Bos indicus cattle

British Journal Of Nutrition ◽

10.1079/bjn19850073 ◽

1985 ◽

Vol 53 (3) ◽

pp. 637-648 ◽

Cited By ~ 55

Author(s):

R. A. Hunter ◽

S. D. Siebert

Keyword(s):

Cell Wall ◽

Bos Taurus ◽

Bos Indicus ◽

Digestion Rate ◽

Heteropogon Contortus ◽

Breed Difference ◽

Cell Wall Constituent ◽

Brahman Steers

1. Six Hereford and six Brahman steers were fed ad lib. Pangola grass (Digztaria decumbens) and Spear grass (Heteropogon contortus) hay alone and supplemented with rumen-degradable nitrogen and sulphur and minerals. The rumen digestion of the two feeds was determined by reference to the disappearance of substrate from nylon bags suspended in the rumen and withdrawn after intervals ranging from 8 to 120 h.2. The digestion of the unsupplemented Pangola grass diet occurred more rapidly in Brahmans than in Herefords and was associated with higher rumen ammonia concentrations in Brahmans (40 v. 16 mg/l). The rumen NH3, concentrations were increased to over 100 mg/l by supplementation. The digestion rate increased in both breeds after supplementation and the breed difference disappeared. Increases in digestion rate were not achieved above NH3, concentrations of 60–80 mg/l.3. Spear grass, especially the cell-wall-constituent fraction, was more resistant to digestion than Pangola grass. Digestion of the unsupplemented Spear grass diet proceeded more rapidly in Brahmans than in Herefords. The digestion rate in Brahmans were similar irrespective of whether the diet was supplemented or not. Supplementation increased digestion rate in Herefords.

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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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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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