2012 BEEF IMPROVEMENT FEDERATION ANNUAL MEETING & RESEARCH SYMPOSIUM PROCEEDINGS
The annual meeting focused on the influence and role of Bos indicus genetics in America. The above link will provide you with scientific research presented at the 2012 BIF Annual Meeting and Research Symposium based on Bos indicus and Brahman influenced cattle.
The following articles are examples of modern research focusing on American Brahman cattle in the Journal of Animal Science, published by the American Society of Animal Science. Please click on each link for a copy of the research abstract.
BRAHMANS USED IN CROSSBREEDING
- Large Effects on Birth Weight Follow Inheritance Pattern Consistent with Gametic Imprinting and X Chromosome. R.M. Thallman*, J.A. Dillon†, J.O. Sanders‡, A.D. Herring‡, S.D. Kachman§, and D.G. Riley‡ – View PDF Abstract
Brahman (BR) cattle contribute substantially to beef production in the Southern and Southeastern regions of the United States, primarily through crossbreeding and Brahman-influenced composite breeds. Birth weights (BW) of calves produced from Brahman sires and Bos taurus dams are considerably heavier with greater differences between sexes than calves of the reciprocal cross (Cartwright et al. (1964); Roberson et al. (1986)). These results suggest that X chromosome inheritance and gametic imprinting should be considered in genetic evaluation of Brahman-influenced cattle and that genomic selection on breed-of-origin, especially for the X chromosome, could be highly effective in Brahman-influenced composites or breeds. At least from the perspective of birth weight, crossbreeding programs should emphasize Brahman contribution to the maternal part of a breeding system and B. taurus to the paternal part. Finally, it seems plausible that introgression of the Brahman X chromosome (or portions of it) and potentially limited autosomal regions responsible for major fractions of the gametic imprinting × sex effect into B. taurus breeds could provide a mechanism for reducing dystocia relative to growth rate through reducing sexual dimorphism for BW.
- IMPACT OF BRAHMAN INFLUENCE ON BREEDING FEMALE PRICES IN SOUTH TEXAS: RESULTS FROM A SPECIAL SALE IN BEE COUNTY, TEXAS
Levi A. Russell, Matthew T. Bochat, Brian D. Yanta, David P. Anderson, Joe C. Paschal, A. Mac Young- View PDF Abstract
Cattle with Brahman influence are of special interest in South Texas because crossbreeding them with British and European breed types typically produces offspring that tolerate heat better and are more resistant to insects and disease. Brahman influence also contributes to longevity, maternal ability, and maternal calving ease. Brahman cattle can be used as straightbreds, but are generally used as crosses to take advantage of the increased hybrid vigor they exhibit (heterosis), especially in the female.
- UTILIZING BRAHMAN GERMPLASM IN CROSSBREEDING SYSTEMS
Matthew L. Spangler, Phd. – View PDF Abstract
Greater than half of the cattle in the world are managed in tropical environments, while approximately 40% of beef cows in the United States are located in subtropical areas. Furthermore, approximately 80% of global beef production is Bos indicusbased. Given this, Bos indicus germplasm plays a critical role in both US and worldwide beef production particularly when used as part of a well-structured crossbreeding program.The decision of whether or not to utilize a particular strategic system of crossbreeding depends upon individual production goals. First must come the blinding realization that no one breed excels in all areas that lead to profitability. In order to take advantage of breed complementarity, breeds must be paired such that they excel in different areas that are critical to the overall production goals. The advantages of crossbreeding can be thought of as: 1) Taking advantage of breed complementarity, 2) Taking advantage of non-additive effects (dominance and epistasis) thus leading to heterosis (hybrid vigor).
- FLORIDA CROSSBREEDING RESEARCH
D.G. Riley, G.R. Hansen, J.R. Crockett, T.A. Olson, C.C. Chase, Jr., and D.E. Franke – View PDF Abstract
This review highlights the accomplishments of three University of Florida beef cattle research locations from the 1940s through the late 1980s. These locations produced estimates of breed effects and heterosis for a variety of traits in Brahman and a number of other breeds. Most importantly, these facilities investigated the crossbred superiority (heterosis retained or expressed) in several crossbreeding systems, including terminal crosses, two and three breed rotations, and inter se matings (including F-1 and 3/8-5/8 parents). Results generally supported the dominance model of heterosis expression for most reproductive and calf growth traits.
- RECIPROCAL DIFFERENCES IN BIRTH WEIGHT IN BRAHMAN X BOS TAURUS CROSSBRED CATTLE
Jasmine Dillon and David Riley – View PDF Abstract
Brahman and Brahman crossbred females have high value in commercial beef cattle herds in the Southern United States. Their improved parasite resistance, heat tolerance, fertility, longevity, and maternal effect on calf growth in addition to increased maternal calving ease make them a desirable cow type for the subtropical climate in the region. There exists a phenomenon related to calf birth weight that producers interested in producing Brahman x Bos taurus crosses should be aware of when making breeding decisions.
- IMPACT OF BOS INDICUS GENETICS ON THE GLOBAL BEEF INDUSTRY
L.V. Cundiff, R.M. Thallman and L.A. Kuehn- View PDF Abstract
More than half of the cattle in the world are maintained in tropical environments between the tropics of Cancer and Capricorn. The tropic of Cancer is located just south of the tip of Texas and Florida. About 40% of the beef cows in the United States are located in relatively hot and humid subtropics of the Southeast or more arid subtropics of the Southwest. Bos indicusgermplasm plays a critical role in providing for adaptation of cattle used for beef production in these regions. Experimental results documenting the importance of using both Bos indicus and Bos taurus breeds in crossbreeding programs or composite populations to exploit heterosis and match genetic potential of cow herds to the climatic environment will be reviewed based primarily on results from the cattle germplasm evaluation (GPE) program at the U.S. Meat Animal Research Center (USMARC), Clay Center, Nebraska conducted in cooperation with experiment stations in the Southern U.S.
- INFLUENCE OF BREED, HETEROZYGOSITY, AND DISEASE INCIDENCE ON ESTIMATES OF VARIANCE COMPONENTS OF RESPIRATORY DISEASE IN PREWEANED BEEF CALVES
G.D. Snowder, L.D. Van Vleck, L.V. Cundiff and G.L. Bennett – View PDF Abstract
The objective of this study was to characterize genetic and environmental factors influencing bovine respiratory disease (BRD) in beef cattle.Records from nine purebred and three composite breeds and a variety of F-1 and three way crosses including the progeny of 12 additional different sire breeds produced over a 20 year period were evaluated for breed and heterozygosity effects on the observed incidence of BRD. Heterozygosity fractions for calves and dams were defined by generalized breed origins: British, Continental and tropically adaptive. Calves that were British x Continental or tropically adaptive x British breeds had a lower incidence of BRD than did calves of British x British breeds.
- PREWEANING EFFICIENCY FOR MATURE COWS OF BREED CROSSES FROM TROPICALLY ADAPTED BOS INDICUS AND BOS TAURUS AND UNADAPTED BOS TAURUS BREEDS
T.G. Jenkins and C.L. Ferrell – View PDF Abstract
Production data was collected on mature cows produced by mating Angus and Hereford, Brahman, Boran and Tuli sires by AI or natural service to Hereford and Angus cows. Means for milk yield at peak lactation, total milk yields, calf birth weight, age-adjusted weaning weights, preweaning daily gain, and feed efficiency were established. Brahman crosses exhibited greater peak and total yield, lower birth weight, greater daily gain and adjusted weaning weight, and higher feed efficiency than did Bos taurus breed crosses.
- CHARACTERIZATION OF BIOLOGICAL TYPES OF CATTLE-CYCLE III: II. GROWTH RATE AND PUBERTY IN FEMALES
Keith E. Gregory, D.B. Laster, L.V. Cundiff, G.M. Smith and R.M. Koch – View PDF Abstract
Data on growth traits, puberty and pregnancy were analyzed on 490 crossbred females produced by artificial inseminationfrom Hereford and Angus dams by Hereford, Angus, Brahman, Sahiwal, Pinzgauer and Tarentaise sires. Brahman crosses were heavier at 200 and 500 days and had the highest pregnancy percentage at 550 days as compared to the other sire breeds.
- LIFE-CYCLE BIOLOGICAL EFFICIENCY OF BOS INDICUS X BOS TAURUS AND BOS TAURUS CROSSBRED COW-CALF PRODUCTION TO WEANING
R.D. Green, L.V. Cundiff and G.E. Dickerson – View PDF Abstract
A model was developed that accounted for all biological inputs and outputs for a theoretical herd of F-1 females at age equilibrium mated to produce three way cross terminal cross calves and for the required proportion of straightbred cows needed to produce replacements. The results obtained indicate that feed cost per unit of weaned calf plus cull cow beef output would be 4% higher using 1/2 blood Brahman cows as compared to other breed crosses due to their efficiencies.
- OUTPUT/INPUT DIFFERENCES AMONG NONPREGNANT, LACTATING BOS INDICUS-BOS TAURUS AND BOS TAURUS-BOS TAURUS F-1 CROSS COWS
R.D. Green, L.V. Cundiff, G.E. Dickerson and T.G. Jenkins – View PDF Abstract
Non-pregnant F-1 crossbred cows, progeny of either Hereford or Angus dams and sired by Brahman, Sahiwal, Pinzgauer, Hereford or Angus sires, were fed to maintain initial weight while rearing Charolais sired progeny for a period of 126 days in a dry lot beginning at about 48 days after calving. Cows and calves were weighed every 2 weeks and feed intake was adjusted to minimize the change in the cows weight. Milk production was estimated by weigh-suckle weigh at 58, 85, 125 and 170 days of lactation. Calf gain relative to cow weight was higher for Brahman cross calves as compared to the rest due to total milk production. The total efficiency of calf gain in weight was 11% greater for crossbred cows of Bos indicu x Bos taurus than for Bos taurus x Bos taurus cows in the 126 day lactation period.
- REPRODUCTIVE PERFORMANCE, CALF GROWTH, AND MILK PRODUCTION OF FIRST-CALF HEIFERS SIRED BY SEVEN BREEDS AND RAISED ON DIFFERENT LEVELS OF NUTRITION
H.C. Freetly and L.V. Cundiff – View PDF Abstract
This study evaluated heifers crossbred from seven breeds of sires (Hereford, Angus, Belgian Blue, Piedmontese, Brahman,Boran and Tuli) and three breeds of dams (Angus, Herefordand MARC III[four breed composite]). Each of the cross heifers was mated to a Red Poll bull to calve at 2 years of age. Measurements of age of calf at partuition, birthweights, calf age at weaning, calf ADG and milk poroduction from 50-200 days were taken. The results showed that milk production from 50 -200 days was the highest for the Brahman sired heifers and as a result their offspring had the highest ADG at weaning time.
- EFFECT OF BREED COMPOSITION ON PHENOTYPIC RESIDUAL FEED INTAKE AND GROWTH IN ANGUS, BRAHMAN, AND ANGUS X BRAHMAN CROSSBRED CATTLE – View PDF Abstract
M.A. Elzo, D.G. Riley, G.R. Hansen, D.D. Johnson, R.O. Myer, S.W. Coleman, C.C. Chase, J.G. Wasdin and J.D. DriverResearch from the ARS, USDA Subtropical Agricultural Research Station in Florida, the University of Florida, North Carolina State University at Plymouth and the North Florida Research & Education Center studied the effect of breed composition on phenotypic residual feed intake and growth in Angus, Brahman, and Angus x Brahman crossbred cattle. The influence of additive and nonadditive genetic effects and temperament on 4 postweaning feed intake and growth traits was evaluated in a group of 581 bull, heifer and steer calves born in 3 Florida herds in 2006 and 2007. Calves had breed composition ranging from 100% Angus to 100% Brahman. The results showed that Feed Efficiency tended to improve (decreased residual feed intake) as the percentage of Brahman increased.
- MATERNAL AND REPRODUCTIVE PERFORMANCE OF BRAHMAN X ANGUS, SENEPOL X ANGUS, AND TULI X ANGUS COWS IN THE SUBTROPICS
C. C. Chase, Jr., D. G. Riley, T. A Olson , S. W. Coleman and A. C. Hammond – View PDF Abstract
Research from the ARS, USDA Subtropical Agricultural Research Station in Florida and the University of Florida studied the maternal and reproductive performance of F-1 cows in the subtropics. This research compared Brahman x Angus cows, Senepol x Angus cows, and Tuli x Angus cows who were all bred to Angus bulls as first calf heifers, and then to Charolais bulls as 3 to 8 year old cows. This data found that the other breeds were comparable to Brahman as far as reproductive performance but that the Brahman crosses exhibited greater peak and total yield, lower birth weight, greater daily gain and adjusted weaning weight, and higher feed efficiency than did Bos taurus breed crosses. The Brahman crosses also had advantages in calf survival.
- PREWEANING EFFICIENCY FOR MATURE COWS OF BREED CROSSES FROM TROPICALLY ADAPTED BOS INDICUS AND BOS TAURUS AND UNADAPTED BOS TAURUS BREEDS
T. G. Jenkins and C. L. Ferrell – View PDF Abstract
This U.S. Meat Animal Research Center (MARC) data shows that tropically adapted Bos indicus were more efficient than Bos taurus. Bos indicus breed crosses exhibited greater peak and total yield, lower birth weight, greater daily gain and adjusted weaning weight, and higher feed efficiency than did Bos taurus breed crosses.
- PREWEANING GROWTH OF F1 TROPICALLY ADAPTED BEEF CATTLE BREEDS X ANGUS AND REPRODUCTIVE PERFORMACE OF THEIR ANGUS DAMS IN ARID RANGELAND
J.W. Holloway, B.G. Warrington, D.W. Forrest, and R.D. Randel – View PDF Abstract
The objective of this study was to determine the preweaning performance of F1 Brahman- Senepol- and Tuli- Angus calves under semiarid south Texas conditions and to evaluate the reproductive performance of their dams. Four hundred eighty-nine records collected over four years were analyzed. The statistical model for performance traits included the effects of breed of sire, year, sex, age of dam, and breed of sire x year. Brahman F1 were heavier at every measurement and appeared to be later-maturing and more able to excel under good forage conditions than the other two F1 breed types. Angus females were observed to have a relatively low reproductive rate and high apparent fetal loss at the first and second compared with the third or later pregnancy.
- DIRECT AND MATERNAL GENETIC EFFECTS DUE TO THE INTRODUCTION OF BOS TAURUS ALLELES INTO BRAHMAN CATTLE IN FLORIDA: I. REPRODUCTION AND CALF SURVIVAL
T.A. Olson, M.A. Elzo, M. Koger, W.T. Butts, Jr. and E.L. Adams – View PDF Abstract
Pregnancy rate, calf survival rate to weaning and calf age at weaning of several types of crossbred cows (2/3 or more Brahman) were compared to those of straightbred Brahman and Angus cows over a 12-year period. The purpose of this study was to determine the relative importance of additive vs. nonadditive effects on reproductive and calf survival traits in a population of cattle whose foundation was selected on the basis of superior reproductive performance under harsh environmental conditions.
- COVARIANCE COMPONENTS AND PREDICTION FOR ADDITIVE AND NONADDITIVE PREWEANING GROWTH GENETIC EFFECTS IN AN ANGUS-BRAHMAN MULRIBREED HERD
M.A. Elzo and D.L. Wakeman – View PDF Abstract
Estimates of covariances and sire expected progeny differences of additive and nonadditive direct and maternal genetic effects for birth and weaning weights were obtained using records from 1,581 straightbred and crossbred calves from the Angus-Brahman multibreed herd at the University of Florida. Sire additive and total direct and maternal genetic predictions for birth and weaning weight tended to increase with the fraction of Brahman alleles, where as non additive direct and maternal genetic predictions were similar for sires of all Angus and Brahman fractions. The results showed that it is feasible to evaluate sires for additive and non additive genetic effects in a structured multibreed population.
- COMPARISON OF CROSSBRED COWS CONTAINING VARIOUS PROPORTIONS OF BRAHMAN IN SPRING OR FALL CALVING SYSTEMS: I. PRODUCTIVITY AS TWO-YEAR-OLDS
M.N. McCarter, D.S. Buchanan and R.R. Frahm – View PDF Abstract
Productivity of two-year-old crossbred cows containing various proportions of Brahman breeding was evaluated using 203 spring-calving heifers over a three year period. All heifers were mated to Limousin sires. Percentage of cows exposed to breeding that weaned a calf was the only trait for which a significant crossbred cow group x season of calving interaction was found. Weaning conformation scores were similar for all calves. Age-adjusted weaning hip height increased as proportion of Brahman breeding increased. Based on numbers of weaned calves, spring calving was more advantageous than fall calving. Averaged across both calving seasons, weaning weight tended to increase as the proportion of Brahman increased.
- COMPARISON OF CROSSBRED COWS CONTAINING VARIOUS PROPORTIONS OF BRAHMAN IN SPRING OR FALL CALVING SYSTEMS: II. MILK PRODUCTION
M.N. McCarter, D.S. Buchanan and R.R. Frahm – View PDF Abstract
Monthly estimates of 24 hour milk yield were obtained on 160 spring-calving and 153 fall-calving crossbred cows containing various proportions of Brahman breeding, all bred to Limousin sires. Milk production was measured using weigh-suckle-weigh procedures. Interactions between crossbred group and season of calving were not significant. Across seasons, milk production rarely was affected by proportion of Brahman breeding; however, milk yield, averaged over six monthly measurements, estimated 24 hour milk yeild ranged from 5.3 kg for Hereford x Angus to 6.2 kg for Brahman x Hereford cows.
- COMPARISON OF CROSSBRED COWS CONTAINING VARIOUS PROPORTIONS OF BRAHMAN IN SPRING OR FALL CALVING SYSTEMS: III. PRODUCTIVITY AS THREE-, FOUR-, AND FIVE-YEAR-OLDS
M.N. McCarter, D.S. Buchanan and R.R. Frahm – View PDF Abstract
Productivity of three-, four-, and five-year-old crossbred cows containing various proportions of Brahman breeding out of Angus or Hereford dams was evaluated using 489 spring-calving and 427 fall-calving records collected over a four-year period. Cows were bred to Limousin sires for the first three years and to Limousin and Salers sires the fourth year. Interactions between crossbred cow group and season of calving were not significant. Percentage of cows exposed to breeding that weaned a calf increased as proportion of Brahman breeding increased, was higher for cows out of Angus dams than for cows out of Hereford dams, and was higher for spring calving cows. As the proportion of Brahman increased, the percentage requiring assistance at birth decreased. Preweaning ADG, adjusted weaning weight, weaning conformation, weaning condition, and adjusted weaning hip height increased as proportion of Brahman breeding increased. The data indicates that Brahman-cross dams can be used to improve reproductive rate and increase preweaning growth rate, and thus weaning weight.
- Development of Molecular Markers to Improve Future Selection Methods for Carcass Traits in Brahman and Brahman Influenced Steers A.M.Royer, C.Shivers, D. Riley, M. Elzo, and M.D. Garcia – View PDF Abstract
Brahman cattle are important in tropical regions due to the breed’s ability to tolerate excessive heat and parasite presence. However, Brahman cattle can exhibit lower carcass quality characteristics when compared to Bos taurus breeds. The objective of this study was to evaluate potential SNP associations on six candidate genes for carcass quality and composition traits in a population of Brahman and Brahman-influenced steers.
- AN EVALUATION OF GENETIC TRENDS OVER 10 YEAR PERIOD FROM DATA COLLECTED FROM THE ABBA CARCASS EVALUATION PROGRAMA.M. Royer, C.Shivers, D. Riley, M. Elzo, J. Paschal, D.E. Franke, and M.D. Garcia – View PDF Abstract
The ABBA carcass evaluation program and Brahman producers have made significant improvement in production, efficiency and carcass traits in a relatively short period of time. The fact that virtually all traits have seen a positive per year increase in performance indicates that Brahman producers are making a concerted effort to improve traits deemed valuable by the beef industry in Brahman cattle. In summary, the ABBA Carcass Evaluation Program has been a success. The program has not only made great strides in Brahman performance and efficiency in the feedlot, but has also shown that Brahman producers are capable of making the Brahman breed competitive with other breeds when it comes to carcass quality and merit.
- FACTORS INFLUENCING TENDERNESS IN STEAKS FROM BRAHMAN CATTLE
D.G. Riley, D.D. Johnson, C.C. Chase, Jr., R.L. West, S.W. Coleman, T.A. Olsen, A.C. Hammond- View PDF Abstract
The objective of this study was to identify a set of explanatory variables for Warner-Bratzler shear force and myofibril fragmentation indices after 7, 14 and 21 days of aging and sensory tenderness after 14 days of aging of steaks from Brahman cattle. Insoluable collagen was negatively associated with all tenderness traits across aging periods. Insoluable collagen may be of special importance and offer a unique opportunity to improve palatability of steaks from purebred Brahman cattle.
- ESTIMATED GENETIC PARAMETERS FOR CARCASS TRAITS OF BRAHMAN CATTLE
D.G. Riley, C.C. Chase, Jr., A.C. Hammond, R.L. West, D.D. Johnson, T.A. Olson and S.W. Coleman- View PDF Abstract
Heritabilities and genetic and phenotypic correlations were estimated from feedlot and carcass data collected from 504 Brahman calves in Central Florida from 1996-2000. It was found that the heritabilities were actually higher than most literature estimates and that sufficient genetic variation exists within the Brahman breed for design and implementation of effective selection programs for important carcass quality and trait yields.
- GENETIC VARIATION AND PREDICTION OF ADDITIVE AND NONADDITIVE GENETIC EFFECTS FOR SIX CARCASS TRAITS IN AN ANGUS-BRAHMAN MULRIBREED HERD
M.A. Elzo, R.L. West, D.D. Johnson and D.L. Wakeman – View PDF Abstract
Estimates of covariances and sire expected progeny differences of additive and nonadditive genetic effects for six carcass traits were obtained using records from 486 straightbred and crossbred steers from 121 sires in the Angus-Brahman multibreed herd of the University of Florida. Sire additive and total direct genetic predictions for longissimus muscle area, marbling, and shear force tended to decrease with the fraction of Brahman alleles, whereas those for hot carcass weight and fat thickness over the longissimus were higher, and those for kidney fat were lower in straightbreds and F-1 than in other crossbred groups. Nonadditive genetic predictions were similar across sire groups of all Angus and Brahman fractions. The results suggest that slaughtering steers on a similar carcass composition basis reduced variability of fat-related traits while retaining variability for non-fat-related traits comparable to slaughtering steers on a similar age or weight basis.
- GENETIC PARAMETERS FOR GROWTH AND CARCASS TRAITS OF BRAHMAN STEERS
T. Smith, J. D. Domingue, J. C. Paschal, D. E. Franke, T. D. Bidner and G. Whipple – View PDF Abstract
This research from faculty at University of Louisiana-Monroe, Louisiana State Agriculture Center, Texas A&M Research and Extension Cetner – Corpus Christi, and Central Community College focuses on EPDs for growth and carcass traits of Brahman steers. It evaluated 467 head of purebred Brahman bull calves, sired by 68 bulls in 17 private herds in Louisiana. The study looked at variation in growth, carcass, and tenderness traits.
PUREBRED BRAHMAN PRODUCTION
- INFLUENCE OF FRAME SIZE AND BODY CONDITION SCORE ON PERFORMANCE OF BRAHMAN CATTLE
C.A. Vargas, T.A. Olson, C.C. Chase, Jr., A.C. Hammond and M.A. Elzo – View PDF Abstract
The effects of frame size and body condition score on performance of Brahman cows were evaluated using records collected from 1984 to 1994 at the Subtropical Agricultural Research Station. The results indicate that the recommended cow size is moderate framed so that the cows can be maintained in adequate body condition under nutritional levels attainable under commercial conditions and produce steer progeny with acceptable carcass weights.
- GENETIC AND NONGENETIC INFLUENCES ON VIGOR AT BIRTH AND PREWEANING MORTALITY OF PUREBRED AND HIGH PERCENTAGE BRAHMAN CALVES
D.G. Riley, C.C. Chase, T.A. Olson, S.W. Coleman and A.C. Hammond – View PDF Abstract
The objectives of this study were to assess the risk associated with proportion Brahman inheritance, cow age, dystocia, and birthdate weather conditions on calf vigor at birth and preweaning mortality. It was found that very little improvements could be made through selection. It is suggested that improvement programs such as scheduling the calving season to avoid detrimental low temperatures, crossing unrelated bloodlines within the breed and cow calf behavior might improve vigor and survivability.
- EFFECTS OF RESTRICTED NURSING ON PHYSIOLOGICAL AND BEHAVIORAL REACTONS OF BRAHMAN CATTLE TO SUBSEQUENT RESTRAINT AND WEANING
Donald C. Lay, Jr., Ted H. Friend, Ron D. Randel, Cindy L. Bowers, Ken K. Grissom, Don A. Neuendorff, Omer C. Jenkins- View PDF Abstract
The influence of restricted nursing on physiological and behavioral reactions to later restraint and weaning was examined in Brahman calves. The calves were blocked for sex and randomly assigned at birth to one of two treatments: restricted nurse (RN), or ad libitum nurse (ALN). The effects of the restricted nursing regimen, which inherently includes handling, appears to alter the calf’s later response to restraint and weaning. However, due to the lack of a uniform response further research is required to determine the meaning and causal factors for this alteration.
- INTERRELATIONSHIPS AMONG GROWTH, ENDOCRINE, IMMUNE AND TEMPERAMENT VARIABLES IN NEONATAL BRAHMAN CALVES
N.C. Burdick, J.P. Banta, D.A. Neuendorff, J.C. White, R.C., Vann, J.C. Laurenz, T.H. Welsh, Jr., and R.D. Randel- View PDF Abstract
Interrelationships among growth, endocrine, immune, and temperaments variables were assessed in neonatal Brahman calves. The velocity upon exiting a working chute (exit velocity) of an animal was measured and used as an objective indicator of temperament to classify calves as calm, intermediate, or temperamental. Calves were weighed weekly and blood samples were collected for plasma and serum to measure concentrations of immunoglobulins. During the neonatal period in this study, there was no relationship of temperament with passive immunity or stress hormone concentrations; however, growth was positively associated with passive immunity and negatively associated with stress hormones. These data can be beneficial in developing best management practices in young calves.