Download or read book Biological Basis for Variation in Residual Feed Intake in Beef Cattle written by Emma Richardson and published by . This book was released on 2002 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sources of Biological Variation in Residual Feed Intake in Beef Cattle written by Phillip Allan Lancaster and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Objectives of this study were to characterize residual feed intake (RFI) in growing calves and to examine relationships with growth, carcass composition, physiological indicators, energy metabolism and reproduction. To accomplish these objectives, multiple experiments were conducted. In all experiments, RFI was calculated as the difference between actual DMI and expected DMI from linear regression of DMI on mid-test metabolic BW and ADG. To examine the relationships between RFI and rate and composition of growth, and reproduction an experiment was conducted with postweaning Brangus heifers (N = 348). Measures of carcass composition (longissimus muscle area, LMA; and 12th rib fat thickness, BF) were obtained by ultrasound at the start and end of each experiment. To determine if serum IGF-I concentration is associated with RFI, two experiments were conducted with Angus bulls and heifers (N = 95) divergently selected for serum IGF-I concentration. To evaluate relationships with energy metabolism, calves with low and high RFI were selected for determination of heart rate as an indicator trait for energy expenditure (4 experiments) and liver mitochondrial function (3 experiments). Residual feed intake was not correlated with ADG, but was positively correlated with gain in BF such that the more efficient calves were leaner. Calves from the low IGF-I selection line had lower RFI suggesting that RFI and IGF-I are related and that IGF-I could be used as an indicator trait to aid in selection for improved RFI in Angus cattle. Calves with low RFI had lower energy expenditure and greater mitochondrial acceptor control ratios than calves with high RFI suggesting improved regulation of energy metabolism. A similar percentage of heifers with low RFI attained puberty as those with high RFI by the end of the experiment. Results from this study indicate that producers can utilize RFI to select for improved feed efficiency with minimal impact on growth, carcass composition and reproduction.
Download or read book Identifying Potential Sources of Variation in Residual Feed Intake in Beef Cattle written by Kevin S. Shaffer and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Feed Efficiency in the Beef Industry written by Rodney A. Hill and published by John Wiley & Sons. This book was released on 2012-09-11 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feed Efficiency in the Beef Industry provides a thorough and concise overview of feed efficiency in beef cattle. It frames the great importance of feed efficiency to the industry and details the latest findings of the many scientific disciplines that intersect and aim to improve efficient and sustainable production of nutritious beef. The vast majority of production costs are directly tied to feed. With increased demand for grains to feed a rapidly increasing world population and to supply a new demand for alternative fuels, feed costs continue to increase. In recent years, the negative environmental impacts of inefficient feeding have also been realized; as such feed efficiency is an important factor in both economic viability and environmental sustainability of cattle production. Feed Efficiency in the Beef Industry covers a broad range of topics ranging from economic evaluation of feed efficiency to the physiological and genetic bases of efficient conversion of feed to high quality beef. Chapters also look at how a fuller understanding of feed efficiency is leading to new selective breeding efforts to develop more efficient cattle. With wide-ranging coverage from leading international researchers, Feed Efficiency will be a valuable resource for producers who wish to understand the complexities, challenges, and opportunities to reduce their cost of production, for students studying the topic and for researchers and professionals working in the beef industry.
Download or read book Feed efficiency in swine written by John F. Patience and published by Springer Science & Business Media. This book was released on 2012-10-15 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: 'Feed efficiency in swine' has been prepared as a comprehensive treatise on the current state of our understanding of this topic which is so important to the pork industry. Each chapter is written by international authorities who understand both the science and application of their topic area. The book provides detailed insight into the many factors affecting feed efficiency, ranging from diet processing to herd health, from nutrition to physiology and from day-to-day barn management to the adoption of advanced technologies. The authors explain such practical aspects as the challenge of interpreting feed efficiency information obtained on farm or the role of liquid feeding. The authors also delve into more scientific topics such as amino acid or energy metabolism or animal physiology. This book is written for people who have a technical interest in pork production, including nutritionists, geneticists, farm management specialists, veterinarians, other academics and, of course, pork producers.
Download or read book Determining Biological Sources of Variation in Residual Feed Intake in Brahman Heifers During Confinement Feeding and on Pasture written by Robert O. Dittmar and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Objectives were to characterize residual feed intake (RFI) and determine the phenotypic correlation between performance, feed efficiency, and other biological measurements in Brahman heifers, as well as the relationship between RFI determined in confinement and measurements of grazing activity on pasture. Three separate 70 d feeding trials were performed, and RFI was determined as the residual between actual and predicted dry matter intake (DMI) for a given level of production. Brahman heifers (n = 103; 5-to-9 mo of age) were individually limit-fed a pelleted 12% CP complete ration daily in Calan gates. Weekly body weight (BW) and DMI data were collected, and predicted DMI was determined by linear regression of actual DMI on mid-test metabolic BW. Ytterbium chloride was used to evaluate digestive kinetics, and fecal samples were collected to determine fecal volatile fatty acids (VFA) concentration and determine apparent dry matter digestibility (DMD) utilizing acid insoluble ash as an internal marker. Measurements of temperament were evaluated on all heifers at weaning. High (n = 6) and low (n = 6) RFI heifers (Exp. I) grazed fescue and ryegrass to determine variation in grazing behavior, DMI, and apparent DMD. Data from all three experiments were pooled, and RFI was not correlated with average daily gain (ADG), DMI, BW, partial efficiency of gain, feed conversion ration, fecal VFA concentration, or any measures of temperament. There were no significant differences in digestive kinetics between the RFI efficiency groups. Fecal samples taken for acid detergent insoluble ash (ADIA) determination were not collected at frequent enough intervals to account for weekly variation in fecal ADIA concentration. Pasture measurements were not different between the efficiency groups for heifers evaluated for grazing behavior, as well as estimated intake as a proportion of BW, or apparent DMD. Results of this study suggest that Bos indicus cattle appear to have similar efficiency traits as Bos taurus and Bos indicus influenced cattle, making this measure of efficiency equally as valid for use in both types of cattle. This indicates that selection based on RFI can be made to increase feed efficiency without affecting ADG or BW in Brahman cattle.
Download or read book Biology of Domestic Animals written by Colin G. Scanes and published by CRC Press. This book was released on 2017-09-01 with total page 509 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is increasing interest in the biology of domestic animals ranging from genomics, transcriptomics, metabolomics, nutritional physiology, and systems biology. This book touches on all of these, with a particular focus on topics such as domestic animals as comparative models to humans, molecular regulation of growth, metabolic efficiency, reproduction, and the impact of stress on growth and development. The book concludes with a discussion on the current and future directions for researchers.
Download or read book Identification of Single Nucleotide Polymorphisms Associated with Economic Traits in Beef Cattle written by Mohammed K. Abo-Ismail and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Examining Mechanisms Contributing to the Biological Variation of Residual Feed Intake in Growing Heifers and Bulls and in Mid gestation Females written by Aimee Hafla and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this study were to characterize residual feed intake (RFI) in growing bulls and heifers and in mid-gestation females to examine relationships with performance, body composition, feeding behavior, digestibility (DMD) and heart rate (HR) and evaluate the impact of RFI on bull fertility and cow forage utilization. Additionally, use of the n-alkane method to predict individual animal variations in intake was investigated. To accomplish these objectives, multiple RFI studies were conducted. In all studies RFI was computed as the difference between actual and expected DMI from linear regression of DMI on mid-test metabolic BW and ADG. To evaluate phenotypic relationships between feed efficiency, scrotal circumference (SC) and semen-quality an experiment was conducted with yearling bulls (N=204). Residual feed intake was not correlated with BW and ADG, but was positively associated with 12th-rib back fat (BF) such that the more efficient bulls were leaner. Bulls with low RFI had similar SC and progressive motility of sperm compared to high-RFI bulls. However percent normal sperm were weakly associated with RFI in a negative manner. To examine phenotypic relationships between heifer postweaning RFI, and performance, efficiency, HR, and DMD of mid-gestation cows, RFI was measured in growing Bonsmara heifers (N=175). Forty-eight heifers with divergent RFI were retained for breeding. Subsequently, intake, performance and feeding behavior was measured on mid-gestation females. Pregnant females classified as having low postweaning RFI continued to consume 22% less feed, spent 25% less time eating, and had 7% lower HR while maintaining similar BW, ADG and body composition compared to high RFI females. A moderate association between RFI in growing heifers and subsequent efficiency of forage utilization in pregnant cows was found. Growing heifers identified as efficient had greater DMD, however DMD in mature cows was similar between RFI groups. The n-alkane method of predicting intake detected differences in intake between divergent RFI groups in mid-gestation females. Results from this study indicate that inclusion of RFI as a component of a multi-trait selection program will improve feed efficiency of growing animals and mid-gestation females with minimal impacts on growth, body composition, and fertility traits.
Download or read book Feed Efficiency in the Beef Industry written by Rodney A. Hill and published by John Wiley & Sons. This book was released on 2012-06-18 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feed Efficiency in the Beef Industry provides a thorough and concise overview of feed efficiency in beef cattle. It frames the great importance of feed efficiency to the industry and details the latest findings of the many scientific disciplines that intersect and aim to improve efficient and sustainable production of nutritious beef. The vast majority of production costs are directly tied to feed. With increased demand for grains to feed a rapidly increasing world population and to supply a new demand for alternative fuels, feed costs continue to increase. In recent years, the negative environmental impacts of inefficient feeding have also been realized; as such feed efficiency is an important factor in both economic viability and environmental sustainability of cattle production. Feed Efficiency in the Beef Industry covers a broad range of topics ranging from economic evaluation of feed efficiency to the physiological and genetic bases of efficient conversion of feed to high quality beef. Chapters also look at how a fuller understanding of feed efficiency is leading to new selective breeding efforts to develop more efficient cattle. With wide-ranging coverage from leading international researchers, Feed Efficiency will be a valuable resource for producers who wish to understand the complexities, challenges, and opportunities to reduce their cost of production, for students studying the topic and for researchers and professionals working in the beef industry.
Download or read book Feed Evaluation written by P. O. Osuji and published by ILRI (aka ILCA and ILRAD). This book was released on 1993-01-01 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Guidelines for Uniform Beef Improvement Programs written by Dixon D. Hubbard and published by . This book was released on 1981 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Relationships of Residual Feed Intake with Performance Profitability Digestibility and Carcass Traits in Individual and Group Pens written by Gustavo Durante Cruz and published by . This book was released on 2007 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Factors Contributing to Variation in Residual Feed Intake in Mature and Growing Beef Animals written by Claire Fitzsimons and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Phenotypic Relationships Between Residual Feed Intake Feeding Behaviour and Temperament in Western Canadian Beef Cattle written by Lindsey Lippens and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feed costs have led the cattle industry to examine the merit of selecting cattle for inputs (feed efficiency) rather than for outputs exclusively (growth). Residual feed intake (RFI) has become a preferred measure of biological efficiency. Feeding behaviour traits (feeding event duration, frequency, head-down time, length and eating rate) and temperament may provide insight into the variation in feed efficiency. Feeding behaviour, RFI (n = 868) and temperament (n = 58) were examined using five classes of beef cattle. Cattle were sorted into low, medium and high RFI groups. Feeding behaviour traits were moderately (-0.21 to 0.56; P 0.05) related to RFI. Bulls fed a grain-based diet spent longer periods lying down than bulls fed a forage-based diet. No relationships (P 0.1) were observed between RFI and bull temperament, indicating that temperament is not correlated with RFI and selecting for low RFI cattle will not negatively impact temperament.
Download or read book Genetics of Residual Feed Intake in Beef Cattle written by and published by . This book was released on 2010 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lawrie s Meat Science written by Fidel Toldra and published by Woodhead Publishing. This book was released on 2017-04-29 with total page 732 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lawrie’s Meat Science, Eighth Edition, provides a timely and thorough update to this key reference work, documenting significant advances in the meat industry, including storage and preservation of meat, the eating quality of meat, and meat safety. The book examines the growth and development of meat animals, from the conversion of muscle to meat and eventual point of consumption. This updated volume has been expanded to include chapters examining such areas as packaging and storage, meat tenderness, and meat safety. Furthermore, central issues such as the effects of meat on health and the nutritional value of meat are analyzed. Broadly split into four sections, the book opens with the fundamentals behind the growth of meat animals. The second section covers the storage and spoilage of meat products, with the third section exploring the eating quality of meat, from flavor to color. The final section reviews meat safety, authenticity, and the effect of meat on health. Encompasses the recognized gold- standard reference for the meat industry Brings together leading experts in each area, providing a complete overview of the meat sciences Includes all the latest advances, bringing this new edition completely up-to-date, including developments in meat quality, safety, and storage
