Progress 10/01/99 to 07/15/02
Outputs
1. What major problem or issue is being resolved and how are you resolving it? Compatibility between beef cattle type (i.e., breed) and the environment is critical in harsh environmental zones such as the subtropics. Cattle breeds adapted to warm climates are limited to the Zebu breeds (Bos indicus), primarily the American Brahman. Several characteristics of purebred Brahman cattle are undesirable and include poor reproductive and feedlot performance, carcass quality including meat tenderness, temperament, and neonate survivability. Solving these problems requires that we first gather knowledge about the genetic variation for important traits (i.e., carcass quality) in breeds currently being used in the subtropical U.S.A. Identification of tender Brahman sire lines or families would allow cow-calf producers to select bulls from these families to improve product quality and marketability. Another approach is the introduction of improved genetics from other countries of
the world that are adapted to tropical environments. 2. How serious is the problem? Why does it matter? From an economic standpoint, over 50% of cash receipts from farm marketings (90 billion dollars per year) are from livestock and livestock products. Nearly 45% of cash receipts from farm marketings of livestock and livestock products are cattle and calves (40 billion dollars per year). Nearly thirty percent of the cattle in the U.S.A. are estimated to have some percentage Brahman breeding. The widespread use of Brahman breeding by commercial beef producers throughout the southern regions of the U.S.A. demonstrates the economic value placed on tolerance to heat, humidity, and diseases including parasites. Due to perceived problems primarily associated with poor feedlot performance and carcass quality including meat tenderness, crossbred feeder calves exhibiting Brahman characteristics, such as long ears or humps, are often heavily discounted by cattle buyers. 3. How does it
relate to the national Program(s) and National Program Component(s) to which it has been assigned? This research evaluates and preserves tropically adapted beef cattle breeds in the subtropics with potential for increasing production efficiency and improving marketability with emphasis on reproductive efficiency and product quality, which contributes to National Program 101, Food Animal Production. The evaluations of different beef cattle breeds are conducted in cooperation with other ARS locations and universities across a range of nutrient and location variables in the subtropics. Research on developing cattle production systems for the subtropical U.S.A. is in cooperation with USDA-ARS Meat Animal Research Center. 4. What was your most significant accomplishment this past year? A. Single Most Significant Accomplishment during FY 2001: The feasibility of selection programs for beef carcass yield, quality, and palatability traits needed to be assessed for Brahman cattle, because the
breed has been persistently criticized for poor performance in these traits as straightbreds and crossbreds. Over 500 steer and heifer progeny sired by 22 Brahman bulls and out of Brahman cows in the STARS herd were produced and fed to 10 mm backfat target at STARS, and carcass and palatability traits were assessed and collected by STARS and University of Florida personnel (R. L. West and D. D. Johnson) after slaughter. We produced the first estimates of heritability and genetic correlation for palatability traits including tenderness for straightbred Brahman cattle. These estimates can be used to design selection programs and(or) to develop EPDs (Expected Progeny Differences) for important carcass traits. B. Other Significant Accomplishment(s), if any: C. Significant Accomplishments/Activities that Support Special Target Populations. 5. Describe your major accomplishments over the life of the project, including their predicted or actual impact? This CRIS consists of three major
studies and there have been major accomplishments for each. We have established a herd of Romosinuano cattle in the U.S.A. through embryo importations from Costa Rica and Venezuela. Purebred Romosinuano from Venezuela are being used to upgrade those from Costa Rica in order to conduct a valid breed evaluation. Genetic differences were established between lines of Romosinuano, and among Romosinuano, Angus, Brahman, and Senepol breeds. In initial evaluations, we demonstrated that Romosinuano bulls and heifers reached puberty earlier than Brahman and at lighter body weights. Being observed to be as heat tolerant as Brahman, Romosinuano have the potential to provide new genetics with improved reproductive efficiency to the region. In the evaluation of beef traits in the Brahman breed, carcass yield and quality were determined to be highly responsive to selection. In our evaluation of reproductive and maternal traits of tropically adapted crossbred (with Angus) beef cows, the
reproductive performance of Tuli crossbred cows was as high or nearly as high as that for Brahman crossbred cows for many traits. The smaller mature size of Tuli crossbreds relative to the other breed groups may be advantageous for subtropical production environments. Weaning weights for calves of Tuli crossbreds were lower than those for calves from both Brahman and Senepol crossbreds, but probably still at an acceptable level. The lower reproductive performance of Senepol crossbreds and the higher birth weight of their calves were undesirable. 6. What do you expect to accomplish, year by year, over the next 3 years? In FY 2003, final results of comparisons among Brahman, Senepol, and Tuli crossbred cows for reproductive and maternal traits, and preweaning performance of their calves will be completed, published, and transferred to cattle producers. In FY 2003, the final analyses for the Carcass Merit Project of carcass traits in Brahman cattle will be completed, and publication
and transfer of results to cattle producers will ensue. 7. What technologies have been transferred and to whom? When is the technology likely to become available to the end user (industry, farmer other scientist)? What are the constraints, if known, to the adoption durability of the technology? Results of analyses of carcass data of progeny from different sires were given to the owners of the sires. Carcass data of progeny were transferred to representatives of the American Brahman Breeders Association (ABBA) and to officials of the National Cattlemen's Beef Association (NCBA): Carcass Merit Project. A major constraint to technology transfer of beef cattle germplasm in the United States is the different adaptation requirements of calves in different phases of the beef production system, (e.g., born and weaned in the humid subtropics, then transported and fed in arid and [or] temperate areas), necessitating long term genotype x environment interaction studies across multiple
environments. 8. List your most important publications and presentations, and articles written about your work (NOTE: this does not replace your review publications which are listed below) "Reproduction in Heat Tolerant Cattle," Annual Meeting for the Southern Section American Society of Animal Science, Orlando, FL, February 3-5, 2002. "The Search for a Combination of Carcass and Productivity Traits in Brahman Cattle," 2002 Beef cattle Short Course, Gainesville, FL, May 1-3, 2002. "Subtropical Agricultural Research Station Field Day 2002," Brooksville, FL, May 23, 2002. "Searching for Tender Brahman Sires," Florida Cattlemen's Association Annual Meeting, Marco Island, FL, June 19-21, 2002. "A Tough Perception," by L. W. Cantu, The Brahman Journal, July 2002, p. 15-16.
Impacts
(N/A)
Publications
- Coleman, S. W., Phillips, W. A., Chase, C. C., Jr., Riley, D. G., Morgan, B., Nelson, J., Olson, T. A. Organ weights and internal fat of Angus or Romosinuano steers finished in the feedlot or with grain-on-pasture. Journal of Animal Science. 2002. v. 80(Suppl. 1): Abstract p. 147.
- Phillips, W. A., Grings, E. E., Coleman, S. W., Short, R. E., Riley, D. G., Chase, C. C., Mayeux, H. S., Heitschmidt, R. K. Winter and spring performance of steer calves reared in temperate or sub-tropic environments and used as stockers on winter wheat pasture in Oklahoma. Journal of Animal Science. 2002. v. 80(Suppl. 1): Abstract p. 147.
- Riley, D. G., Chase, C. C., Jr., Pringle, T. D., West, R. L., Johnson, D. D., Hammond, A. C., Olson, T. A., Coleman, S. W. Effect of sire on rate and extent of postmortem increase in myofibrillar fragmentation indices of Brahman longissimus steaks. Journal of Animal Science. 2002. v. 80(Suppl. 1): Abstract p. 322.
- Brenneman, R. A., Chase, C. C., Jr., Riley, D. G., Olson, T. A., Coleman, S. W. Genetic diversity among the Angus, the American Brahman, the Senepol, and the Romosinuano cattle breeds. Journal of Animal Science. 2002. v. 80(Suppl. 1): Abstract p. 378.
- Brenneman, R.A., Chase, C.C., Jr., Coleman, S.W., Olson, T.A., Rohrer, G.A. Detectionof origin between two bloodlines of Romosinuano cattle using microsatellite screening. Tropical Agriculture (Trinidad). 2001. v. 78. p. 255-262.
- Chase, C. C., Jr. Embryo transfer in tropically adapted cattle in the semitropics. Fields, M. J., Sand, R. S., Yelich, J. V., editors. CRC Press, Boca Raton, FL. Factors Affecting Calf Crop: Biotechnology of Reproduction. 2002. p. 145-155.
- Spicer, L. J., Chase, C. C., Jr., Rutter, L. M. Relationship between serum insulin-like growth factor-I and genotype during the postpartum interval in beef cows. Journal of Animal Science. 2002. v. 80. p. 583- 590.
- Riley, D. G., Chase, C. C., Jr., Hammond, A. C., West, R. L., Johnson, D. D., Olson, T. A., Coleman, S. W. Estimated genetic parameters for carcass traits of Brahman cattle. Journal of Animal Science. 2002. v. 80. p. 955-962.
- Landaeta-Hernandez, A. J., Yelich, J. V., Lemaster, J. W., Fields, M. J., Tran, T., Chase, C. C., Jr., Rae, D. O., Chenoweth, P. J. Environmental, genetic and social factors affecting the expression of estrus in beef cows. Theriogenology. 2002. v. 57. p. 1357-1370.
- Block, J., Chase, C. C., Hansen, P. J. Importance of maternal versus paternal contributions for resistance of bovine preimplantation embryos to heat shock. Biology of Reproduction. 2002. v. 66(Suppl. 1): Abstract p. 154.
- Riley, D. G., Chase, C. C., Jr., Hammond, A. C., Olson, T. A., Coleman, S. W. Genetic parameters for calf birth vigor and calf survival to weaning in a Florida Brahman herd. Journal of Animal Science. 2002. v. 80(Suppl. 2): Abstract p. 4.
- Coleman, S. W., Phillips, W. A., Riley, D. G., Chase, C. C., Mayeux, H. S. Stocker and feedlot performance of Angus and Romosinuano steer calves. Journal of Animal Science. 2002. v. 80(Suppl. 2): Abstract p. 4-5.
- Strauch, T. A., Abbey, C. A., Koch, J. W., Tatman, S. R., Chase, C. C., Jr. , Randel, R. D., Welsh, T. H., Jr. Expression of mRNA for growth hormone receptor, IGF-I, FSH-receptor, and LH-receptor in testis tissue of Angus, Brahman, and Romosinuano bulls. Journal of Animal Science. 2002. v. 80(Suppl. 2): Abstract p. 19.
- Chase, C. C., Jr., Riley, D. G., Hammond, A. C., Olson, T. A., West, R. L., Johnson, D. D., Coleman, S. W. The search for a combination of carcass and productivity traits in Brahman cattle. Proceedings of the 51st University of Florida Beef Cattle Short Course. 2002. p. 51-59.
|
Progress 10/01/00 to 09/30/01
Outputs
1. What major problem or issue is being resolved and how are you resolving it?
Compatibility between beef cattle type (i.e., breed) and the environment is critical in harsh environmental zones such as the subtropics. Cattle breeds adapted to warm climates are limited to the Zebu breeds (Bos indicus), primarily the American Brahman. Several characteristics of purebred Brahman cattle are undesirable and include poor reproductive and feedlot performance, lower carcass quality including meat tenderness, temperament, and poor neonate survivability. Solving these problems requires that we first gather knowledge about the genetic variation for important traits (i.e., carcass quality)in breeds currently being used in the subtropical U.S.A. Identification of tender Brahman sire lines or families would allow cow-calf producers to select bulls from these families to improve product quality and marketability. Another approach to resolving the problem is by introducing improved genetics from other countries of the world that are adapted to tropical environments.
2. How serious is the problem? Why does it matter?
From an economic standpoint, over 50% of cash receipts from farm marketings (90 billion dollars per year) are from livestock and livestock products. Nearly 45% of cash receipts from farm marketings of livestock and livestock products are cattle and calves (40 billion dollars per year). Nearly thirty percent of the cattle in the U.S.A. are estimated to have some percentage Brahman breeding. The widespread use of Brahman breeding by commercial beef producers throughout the southern regions of the U.S.A. demonstrates the economic value placed on tolerance to heat, humidity, and diseases including parasites. Due to perceived problems primarily associated with poor feedlot performance and carcass quality including meat tenderness, crossbred feeder calves exhibiting Brahman characteristics, such as long ears or humps, are often heavily discounted by cattle buyers.
3. How does it relate to the National Program(s) and National Component(s)?
This research evaluates and preserves tropically adapted beef cattle breeds in the subtropics with potential for increasing production efficiency and improving marketability with emphasis on reproductive efficiency and product quality, which contributes to National Program 101, Food Animal Production. The evaluations of different beef cattle breeds are conducted in cooperation with other ARS locations and Universities across a range of nutrient and location variables in the subtropics. Research on developing cattle production systems for the subtropical U.S.A. is in cooperation with USDA-ARS Meat Animal Research Center.
4. What were the most significant accomplishments this past year?
A. Single Most Significant Accomplishment during FY 2001: The feasibility of selection programs for beef carcass yield, quality, and palatability traits needed to be assessed for Brahman cattle, because the breed has been persistently criticized for poor performance in these traits as straightbreds and crossbreds. Over 500 steer and heifer progeny sired by 22 Brahman bulls and out of Brahman cows in the STARS herd were produced, fed to 10 mm backfat target, and slaughtered. Genetic parameters, including heritabilities and correlations between traits, were estimated for carcass traits such as marbling score and quality grade, and these indicated that substantial genetic variation exists within the breed. These parameters could be used to design selection programs and(or) develop EPDs (Expected Progeny Differences) for important carcass traits. B. Other Significant Accomplishment(s), if any: None to report. C. Significant Accomplishments/Activities that Support Special Target
Populations. None to report.
5. Describe the major accomplishments over the life of the project including their predicted or actual impact.
This CRIS consists of three major studies and there have been major accomplishments for each. We have established a herd of Romosinuano cattle in the U.S.A. through embryo importations from Costa Rica and Venezuela. Purebred Romosinuano from Venezuela are being used to upgrade those from Costa Rica in order to conduct a valid breed evaluation. DNA marker analyses were used to establish genotypic uniqueness between the two bloodlines. In initial evaluations, we demonstrated that Romosinuano bulls and heifers reached puberty earlier than Brahman and at lighter body weights. Being observed to be as heat tolerant as Brahman, Romosinuano have the potential to provide new genetics with improved reproductive efficiency to the region. In our evaluation of reproductive and maternal traits of tropically adapted crossbred beef cows, a greater percentage of Tuli x Angus cows calved as five- and six-year-olds than did Brahman x Angus or Senepol x Angus cows, but no differences were observed
at earlier ages. Brahman x Angus cows were larger and heavier than cows of the other breed crosses, and their calves are heavier at weaning.
6. What do you expect to accomplish, year by year, over the next 3 years?
In FY 2002, final analyses of comparisons of Brahman, Senepol, and Tuli crossbred cows for reproductive, maternal traits, and preweaning performance of their calves will be completed. Microsatellite (DNA marker) screening of the Romosinuano, Senepol, Angus, and Brahman will be completed, and genetic distances based on the herd samples will be estimated among these breeds under evaluation. Also in FY 2002, the first calves will be born to determine heterosis among Romosinuano, Angus, and Brahman cattle. In FY 2003, the final analyses for the Carcass Merit Project of carcass traits in Brahman cattle will be completed. In FY 2004, initial estimates of heterosis for preweaning traits among Angus, Brahman, and Romosinuano calves will be determined.
7. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end user (industry, farmer, other scientists)? What are the constraints if known, to the adoption & durability of the technology product?
Technology transfer of research findings and potential impacts was discussed with various producers, producer groups (e.g., National Cattlemen's Beef Association and Florida Cattlemen's Association), and international visitors. Scientists at the unit interacted with several Brahman breeders from throughout the southern U.S.A. and with representatives of the American Brahman Breeders Association and Florida Brahman Association to discuss current and future research studies. Scientists at the unit were also involved in technical interaction with private Romosinuano cattle breeders from Venezuela and with representatives from the Romosinuano breed association of Venezuela. A major constraint to technology transfer of beef cattle germplasm is that maximal production efficiency may only be achieved when animal genetic resources are matched to environmental resources. This is difficult in the subtropics where cows and calves must be adapted to hot and humid weather but after weaning,
calves are transported to other areas of the country and fed in feedlots in cooler climates. Therefore, genetics and breeding programs that take these factors into account are of extreme importance; however, relatively long generation intervals and genotype x environment interactions necessitate longer term breeding projects conducted across multiple environments.
8. List your most important publications in the popular press (no abstracts) and presentations to non-scientific organizations and articles written about your work (NOTE: this does not replace your peer-reviewed publications which are listed below)
"Searching for Tender Brahman Sires," Florida Brahman Association Annual Meeting, St. Cloud, FL, May 26, 2001. "Searching for Tender Brahman Sires," Florida Cattlemen's Association Annual Meeting, Marco Island, FL, June 20-22, 2001.
Impacts
(N/A)
Publications
- Chase, C.C., Jr., Chenoweth, P.J., Larsen, R.E., Hammond, A.C., Olson, T.A., West, R.L., Johnson, D.D. Growth, puberty, and carcass characteristics of Brahman-, Senepol-, and Tuli-sired F1 Angus bulls. Journal of Animal Science. 2001. v. 79. p. 2006-2015.
- Paula-Lopes, F.F., Chase, C.C., Jr., Al-Katanani, Y.M., Krininger, C.E., III, Rivera, R.M., Tekin, S., Majewski, A.C., Ocon, O.M., Olson, T.A., Hansen, P.J. Breed differences in resistance of bovine preimplantation embryos to heat shock. Theriogenology. 2001. v. 55. Abstract p. 430.
- Koch, J.W., Chase, C.C., Jr., Tatman, S.R., Neuendorff, D.A., Wilson, T.W., Strauch, T.A., Randel, R.D., Welsh, T. H., Jr. Comparison of endocrine and reproductive tissue weights in tropically-adapted Bos taurus, temperate Bos taurus and tropically-adapted Bos indicus bulls. Journal of Animal Science. 2001. v. 79(Suppl. 2): Abstract p. 4.
- Tatman, S.R., Chase, C.C., Wilson, T.W., Neuendorff, D.A., Lewis, A.W., Brown, C.G., Randel, R.D. Comparison of traits at puberty of four recently introduced breeds to Angus and Brahman bulls. Journal of Animal Science. 2001. v. 79(Suppl. 2): Abstract p. 4.
- Riley, D.G., Chase, C.C., Jr., Coleman, S.W. Sire effects on feedlot growth of straightbred Brahman calves in Central Florida. Journal of Animal Science. 2001. v. 79(Suppl. 2): Abstract p. 7.
- Krininger, C.E., III, Block, J., Al-Katanani, Y.M., Rivera, R.M., Chase, C.C., Jr., Hansen, P.J. Differences in resistance to heat shock between 2-4 cell Brahman and Holstein embryos produced in vivo. Journal of Animal Science. 2001. v. 79(Suppl. 1): Abstract p. 10.
- Tatman, S.R., Chase, C.C., Neuendorff, D.A., Lewis, A.W., Wilson, T.W., Brown, C.G., Randel, R.D. Comparison of traits at sexual maturity of recently introduced breeds to Angus and Brahman bulls. Journal of Animal Science. 2001. v. 79(Suppl. 1): Abstract p. 229.
- Koch, J.W., Livingston, K.N., Tatman, S.R., Alberts, D., Stocco, D.M., Chase, C.C., Jr., Randel, R.D., Welsh, T.H., Jr. Comparison of adrenal and testis content of the steroidogenic acute regulatory (StAR) and P450 side-chain cleavage enzyme proteins in Angus, Brahman and Romosinuano bulls. Journal of Animal Science. 2001. v. 79(Suppl. 1): Abstract p. 229-230.
- Strauch, T.A., Koch, J.W., Tatman, S.R., Chase, C.C., Jr., Abbey, C.A., Bryan, T.M., Randel, R.D., Welsh, T.H., Jr. Evaluation of somatotrophic axis gene expression and function in Angus, Romosinuano, and Brahman bulls. Journal of Animal Science. 2001. v. 79(Suppl. 1): Abstract p. 230.
- Koch, J.W., Tatman, S.R., Neuendorff, D.A., Wilson, T.W., Lewis, A.W., Chase, C.C., Welsh, T.H., Randel, R.D. The effects of management stressors on cortisol production in various breeds of bulls. Journal of Animal Science. 2001. v. 79(Suppl. 1): Abstract p. 278.
- Brenneman, R.A., Chase, C.C., Jr., Olson, T.A., Riley, D.G., Coleman, S.W. Genetic variation between two tropically adapted Bos taurus breeds, the Romosinuano and the Senepol. Journal of Animal Science. 2001. v. 79(Suppl. 1): Abstract p. 408.
- Chase, C.C., Jr., Larsen, R.E., Sheerin, P.C., Williams, M.J., Hammond, A.C., Olson, T.A., Coleman, S.W. Postweaning growth and puberty of Angus and Romosinuano bulls in Florida. Journal of Animal Science. 2001. v. 79(Suppl. 1): Abstract p. 467.
- Prieto, I., Goetsch, A.L., Banskalieva, V., Cameron, M., Puchala, R., Sahlu, T., Dawson, L.J., Coleman, S.W. Effects of dietary protein concentration on postweaning growth of Boer crossbred and Spanish goat wethers. Journal of Animal Science. 2000. v. 78. p. 2275-2281.
- Phillips, W.A., Brown, M.A., Brown, A.H., Jr., Coleman, S.W. Genotype x environment interactions for postweaning performance in crossbred calves grazing winter wheat pasture or dormant native prairie. Journal of Animal Science. 2001. v. 79. p. 1370-1377.
- Hansen, P.J., Drost, M., Rivera, R.M., Paula-Lopes, F.F., Al-Katanani, Y.M., Krininger, C.E., III, Chase, C.C., Jr. Adverse impact of heat stress on embryo production: Causes and strategies for mitigation. Theriogenology. 2001. v. 55. p. 91-103.
|
Progress 10/01/99 to 09/30/00
Outputs
1. What major problem or issue is being resolved and how are you resolving it?
Compatibility between beef cattle type (i.e., breed) and the environment is critical in harsh environmental zones such as the subtropics. In contrast to the abundance of beef cattle genotypes in the U.S.A. that are adapted to temperate climates, sources of germplasm with adaptation to warm climates, including the subtropics, are generally limited to the Zebu breeds (Bos indicus) and within these primarily the American Brahman. Several characteristics of purebred Brahman cattle are undesirable and include poor reproductive and feedlot performance, carcass quality including meat tenderness, temperament, and neonate survivability. Solving these problems requires that we first gather knowledge about the genetic variation for important traits (i.e., carcass quality)in breeds currently being used in the subtropical U.S.A. Identification of tender Brahman sire lines or families would allow cow-calf producers to select bulls from these families to improve product quality and
marketability. Another approach is the introduction of improved genetics from other countries of the world that are adapted to tropical environments.
2. How serious is the problem? Why does it matter?
From an economic standpoint, over 50% of cash receipts from farm marketings (90 billion dollars per year) are from livestock and livestock products. Nearly 45% of cash receipts from farm marketings of livestock and livestock products are cattle and calves (40 billion dollars per year). Nearly thirty percent of the cattle in the U.S.A. are estimated to have some percentage Brahman breeding. The widespread use of Brahman breeding by commercial beef producers throughout the southern regions of the U.S.A. demonstrates the economic value placed on tolerance to heat, humidity, and diseases including parasites. Due to perceived problems primarily associated with poor feedlot performance and carcass quality including meat tenderness, crossbred feeder calves exhibiting Brahman characteristics, such as long ears or humps, are often heavily discounted by cattle buyers.
3. How does it relate to the National Program(s) and National Component(s)?
This research evaluates and preserves tropically adapted beef cattle breeds in the subtropics with potential for increasing production efficiency and improving marketability with emphasis on reproductive efficiency and product quality, which contributes to National Program 101, Food Animal Production. The evaluations of different beef cattle breeds are conducted in cooperation with other ARS locations and Universities across a range of nutrient and location variables in the subtropics. Research on developing cattle production systems for the subtropical U.S.A. is in cooperation with USDA-ARS Meat Animal Research Center.
4. What were the most significant accomplishments this past year?
A. Single Most Significant Accomplishment during FY 2000 year: The Romosinuano, a tropically adapted and purportedly highly fertile beef cattle breed native to Colombia, was introduced to the U.S.A. from embryo importations from Costa Rica and Venezuela during the last decade. In order to conduct valid evaluations of this breed there was a need to evaluate differences between these two imported lines using both traditional breeding methods and advanced molecular technologies. Using microsatellite markers we demonstrated that significant genetic differences exist between the two bloodlines. These results are directly applicable to our breeding scheme for the evaluation of the Romosinuano because, beyond historical information regarding the development of the two bloodlines, there is now the genetic evidence that the two lines are distinguishable across our sample of the genome and should be evaluated for differences in reproductive, growth, nutritional, and carcass merit traits.
These results demonstrate the application of using information from bovine gene mapping studies and across breed diversity studies to assess genetic diversity within breeds at the bloodline level. B. Other Significant Accomplishment(s), if any: None to report. C. Significant Accomplishments/Activities that Support Special Target Populations. None to report.
5. Describe the major accomplishments over the life of the project including their predicted or actual impact.
This CRIS is new, but in reality a continuation of the previous one. Historically, there has been at least one major accomplishment for each of three major studies being conducted. First, significant sire effects on tenderness and USDA quality grade were observed in a progeny test of Brahman sires. Of fourteen Brahman sires evaluated in the first three years of a five year study, progeny from one sire were most tender and progeny from three sires were ranked the highest for USDA quality grade. These results indicate that selection of Brahman sires for tenderness and carcass quality traits may lead to more acceptable tenderness and higher USDA quality grades (higher price) for their progeny. Second, we have established a herd of Romosinuano cattle in the U.S.A. through embryo importations from Costa Rica and Venezuela. Purebred Romosinuano from Venezuela are being used to upgrade those from Costa Rica in order to conduct a valid breed evaluation. In initial evaluations, we
demonstrated that Romosinuano bulls and heifers from Costa Rica reached puberty earlier than Brahman and at lighter body weights. Being observed to be as heat tolerant as Brahman, Romosinuano have the potential to provide new genetics with improved reproductive efficiency to the region. Third, in our evaluation of reproductive and maternal traits of tropically adapted crossbred beef cows, a greater percentage of Tuli x Angus cows calved as five- and six-year-olds than did Brahman x Angus or Senepol x Angus cows, but no differences were observed at earlier ages. Brahman x Angus cows were larger and heavier than cows of the other breed crosses and their calves are heavier at weaning.
6. What do you expect to accomplish, year by year, over the next 3 years?
In FY 2001, the final data (feedlot and carcass data) analysis for the five year progeny test to determine genetic control of tenderness in Brahman cattle will be completed, and information transferred to producers on potential for breeding Brahmans to improve performance and carcass quality. In FY 2002, ARS will release comparisons of Brahman, Tuli, and Senepol crossed cows for reproductive, maternal traits and post-weaning performance of the offspring. Microsatellite screening of the Romosinuano, Senepol, Angus, and Brahman will be completed and genetic distances based on the herd samples will be estimated between these breeds under evaluation. Also in FY 2002, the first calves will be born to determine heterosis among Romosinuano, Angus, and Brahman cattle. Heterosis will be evaluated with respect to genetic distances between breeds to determine the correlation between genetic diversity and heterosis for different traits.
7. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end user (industry, farmer, other scientists)? What are the constraints if known, to the adoption & durability of the technology product?
Technology transfer of research findings and potential impacts were discussed with various producers, producer groups (e.g., National Cattlemen's Association and Florida Cattlemen's Association), and international visitors. Scientists at the unit interacted with several Brahman breeders from throughout the southern U.S.A. and with representatives of the American Brahman Breeders Association and Florida Brahman Association to discuss current and future research studies. Scientists at the unit were also involved in technical interaction with private Romosinuano cattle breeders from Mexico, Costa Rica, and Venezuela and with representatives from the Romosinuano breed association of Venezuela. A major constraint to technology transfer of beef cattle germplasm is that maximal production efficiency may only be achieved when animal genetic resources are matched to environmental resources. This is difficult in the subtropics where cows and calves must be adapted to hot and humid weather
but after weaning, calves are transported to other areas of the country and fed in feedlots in cooler climates. Therefore, genetics and breeding programs that take these factors into account are of extreme importance; however, relatively long generation intervals and genotype x environment interactions necessitate longer term breeding projects conducted across multiple environments.
8. List your most important publications in the popular press (no abstracts) and presentations to non-scientific organizations and articles written about your work (NOTE: this does not replace your peer-reviewed publications which are listed below)
Forty-Ninth Annual Beef Cattle Short Course, May 3-5, 2000, Gainesville, FL (over 500 registered producers, consultants, and dealers).
Impacts
(N/A)
Publications
- Vargas, C.A., Olson, T.A., Chase, C.C., Jr., Hammond, A.C., Elzo, M.A. Influence of frame size and body condition score on performance of Brahman cattle. Journal of Animal Science. 1999. v.77.p.3140-3149.
- Chase, C.C., Jr., Hammond, A.C., Olson, T.A., West, R.L., Johnson, D.D. Effects of sire on feedlot performance and carcass characteristics in purebred Brahman cattle: an update. XVI Reunion Latinoamericana de Produccion Animal y III Congreso Uruguayo de Produccion Animal, Montevideo, Uruguay. Marzo 28-31, 2000. [CD-ROM].
- Olson, T.A., Lucena, C., Chase, C.C., Jr. Evaluation of the impact of hair coat type on rectal temperatures, milk production and calving interval in Holstein x Carora crossbred cows in Venezuela. XVI Reunion Latinoamericana de Produccion Animal y III Congreso Uruguayo de Produccion Animal, Montevideo, Uruguay. Marzo 28-31, 2000. [CD-ROM].
- Chase, C.C., Jr. Embryo transfer in tropically adapted cattle in the semitropics, p.121-130. 49th Annual Beef Cattle Short Course Proceedings, "Biotechnologies of Reproductive Biology," University of Florida, Gainesville. May 3-5, 2000. p.170.
- Chase, C.C., Jr., Hammond, A.C., Olson, T.A. Effect of tropically adapted sire breeds on preweaning growth of F1 Angus calves and reproductive performance of their Angus dams. Journal of Animal Science. 2000. v.78.p.1111-1116.
- Alvarez, P., Spicer L.J., Chase, C.C., Jr, Payton, M.E., Hamilton, T.D., Stewart, R.E., Hammond, A.C., Olson, T.A., Wettemann, R.P. Ovarian and endocrine characteristics during an estrous cycle in Angus, Brahman, and Senepol cows in a subtropical environment. Journal of Animal Science. 2000. v.78.p.1291-1302.
- Chenoweth, P.J., Chase, C.C., Jr., Risco, C.A., Larsen, R.E. Characterization of gossypol-induced sperm abnormalities in bulls. Theriogenology. 2000. v.53.p.1193-1203.
- Liu, J., Boyd, C.K., Kobayashi, Y., Chase, C.C., Jr., Hammond, A.C., Olson, T.A., Elsasser, T.H., Lucy, M.C. A novel phenotype for Laron dwarfism in miniature Bos indicus cattle suggests that the expression of growth hormone receptor 1A in liver is required for normal growth. Domestic Animal Endocrinology. 1999. v.17.p.421-437.
- Brenneman, R.A., Chase, C.C., Jr., Olson T.A., Rohrer, G.A., Coleman, S.W. Detection of origin between two bloodlines of Romosinuano cattle using microsatellite screening, D029. 27th International Conference on Animal Genetics, Animal Genomics: Synthesis of Past, Present, and Future Directions, University of Minnesota. July 22-26, 2000. [CD-ROM].
- Chase, C.C., Jr., Williams, M.J., Hammond, A.C., Olson, T.A. Effect of source of Romosinuano germplasm and preweaning creep grazing on postweaning growth and puberty in heifers. Journal of Animal Science. 2000. v.78 (Suppl. 1).p.222.
- Eastridge, J.S., Solomon, M.B., West, R.L., Chase, C.C., Jr. Tenderizing meat from Brahman cattle: Hydrodynamic pressure process and within-muscle effects for bottom round. Journal of Animal Science. 2000. v.78 (Suppl. 1).p.161.
|
|