Download or read book Some Genetic and Environmental Factors Affecting the Hatchability of Hens Eggs written by John Bryant Lupton and published by . This book was released on 1926 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Environment on Nutrient Requirements of Domestic Animals written by National Research Council and published by National Academies Press. This book was released on 1981-02-01 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of Some Factors Affecting the Hatch ability of Chicken Eggs with Special Reference to Genetic Control written by P. Hunton and published by . This book was released on 1960 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Genetic and Environmental Factors Influencing Criteria for Measuring Egg Quality in the Fowl written by Sam Louis Scheinberg and published by . This book was released on 1950 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Domestication and early experiences in chickens written by Pia Katrine Løtvedt and published by Linköping University Electronic Press. This book was released on 2017-11-17 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: A number of animal species have undergone domestication, the process of becoming adapted to living in captivity and in proximity to humans. Common for these species is that they have all developed certain traits, including changes to coat color, body size and level of fearfulness. This has been termed the domestic phenotype. Among these traits is also an attenuation of the response to stress, both behaviorally and physiologically. Thus, release of glucocorticoids such as cortisol or corticosterone is lower in domesticated species. However, the underlying mechanism for this is not yet well understood. In this thesis, we have investigated genetic mechanisms for the attenuation of the physiological stress response in ancestral chickens, the Red Junglefowl, and domesticated chickens, the White Leghorn. We found a number of genes that differed in expression between the two breeds in several tissues involved in the stress response. Among the most interesting findings were lower expression of genes involved in production and secretion of ACTH in the pituitary, and in the production of glucocorticoids in the adrenal glands, in the domesticated White Leghorns. We also found higher expression of the glucocorticoid receptor in White Leghorns, indicating that they may have a more efficient negative feedback of the physiological stress response. We then investigated the transcriptome of the chicken pituitary more closely, and we discovered that a number of genes highly involved in several important physiological axes showed differential expression between the ancestral and the domesticated breed. Among these were genes involved in the stress response, the reproductive system, and in metabolism and growth. As these traits are modified in domesticated species, our results suggest that changes to gene expression in the pituitary may be an important underlying factor of the domestic phenotype. A separate aim of this thesis was to investigate effects of hatching time in chickens on their subsequent phenotype. Time of hatching constitutes an early experience that may differ between individuals, and we therefore hypothesized that differences in hatching time would affect chickens later in life. While a number of studies have been performed on hatching time and post-hatch growth, very little work has been done on effects on behavior. We found that the time of hatching had sex-specific effects. Hatching times in females were negatively correlated with body weight, whereas in males, behaviors such as reaction to novelty and spatial learning were affected. As time of hatching is governed by various hormones, including thyroid hormone and corticosterone, we suggest that changes to the levels of these hormones could affect both hatching time and post-hatch phenotypes. Understanding these mechanisms better would be beneficial in terms of production, where batch homogeneity is important, in research on early experiences and the potential for maternal programming, and in evolutionary questions on trade-off between different life strategies.
Download or read book Poultry Genetics Breeding and Biotechnology written by W.M. Muir and published by Lulu.com. This book was released on 2003 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Factors Affecting the Hatchability of Hen s Eggs with Special Reference to the Physical Factors written by Norma Augusta Frank and published by . This book was released on 1928 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Hatchability of Chicken Eggs as Influenced by Environment and Heredity written by Walter Landauer and published by . This book was released on 1961 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Environmental Heterogeneity on the Estimation of Genetic Value of Chickens written by Johannes Abplanalp and published by . This book was released on 1955 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The U S Egg and Poultry Magazine written by and published by . This book was released on 1933 with total page 828 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Some Factors Affecting the Weight Composition and Hatchability of Hen Eggs Classic Reprint written by Horace Atwood and published by Forgotten Books. This book was released on 2018-02-22 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Some Factors Affecting the Weight, Composition and Hatchability of Hen Eggs The tests indicate that when fowls are fed too scantily the fertility of the eggs will be low, but those which are fertile seem to hatch practically as well as the fertile eggs laid by the fowls fed heavily. Hatch 5 indicates that after fowls have been laying heavily for a considerable length of time their eggs are less fertile and do not hatch so well as eggs laid by fowls which are just reaching or have reached their maximum egg production for the season. There seems to be no great difference in the vigor of the chicks from the two lots of fowls, although what difference there is seems to be in favor of the chicks from the fowls fed scantily, ex cept in the case of the last hatch. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
Download or read book The National Poultry Journal written by and published by . This book was released on 1924 with total page 800 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Poultry Breeding and Genetics written by R. D. Crawford and published by Elsevier Science Health Science Division. This book was released on 1990 with total page 1123 pages. Available in PDF, EPUB and Kindle. Book excerpt: Poultry biology; Qualitative genetics; New directions in poultry genetics; Quantitative genetics and selection; Applied breeding and selection.
Download or read book U S Egg and Poultry Magazine written by and published by . This book was released on 1933 with total page 824 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Some Factors Affecting the Weight Composition and Hatchability of Hen Eggs written by Horace Atwood and published by . This book was released on 1914 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Commercial Chicken Meat and Egg Production written by Donald D. Bell and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 1422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Commercial Chicken Meat and Egg Production is the 5th edition of a highly successful book first authored by Dr. Mack O. North in 1972, updated in 1978 and 1984. The 4th edition was co-authored with Donald D. Bell in 1990. The book has achieved international success as a reference for students and commercial poultry and egg producers in every major poultry producing country in the world. The 5th edition is essential reading for students preparing to enter the poultry industry, for owners and managers of existing poultry companies and for scientists who need a major source of scientifically based material on poultry management. In earlier editions, the authors emphasized the chicken and its management. The 5th edition, with the emphasis shifted to the commercial business of managing poultry, contains over 75% new material. The contributions of 14 new authors make this new edition the most comprehensive such book available. Since extensive references are made to the international aspects of poultry management, all data are presented in both the Imperial and Metric form. Over 300 tables and 250 photos and figures support 62 chapters of text. New areas include processing of poultry and eggs with thorough discussions of food safety and further processing. The business of maintaining poultry is discussed in chapters on economics, model production firms, the use of computers, and record keeping. Updated topics include: breeders and hatchery operations; broiler and layer flock management; replacement programs and management of replacements; nutrition; and flock health. New chapters address flock behavior, ventilation, waste management, egg quality and egg breakage. Other new features include a list of more than 400 references and a Master List of the tables, figures, manufacturers of equipment and supplies, research institutions, books and periodicals, breeders, and trade associations. Commercial growers will find the tables of data of particular interest; scientists will be able to utilize the extensive references and to relate their areas of interest to the commercial industry's applications; and students will find that the division of the book into 11 distinct sections, with multiple chapters in each, will make the text especially useful.
Download or read book A Summary of Reported Estimates of Heritabilities and of Genetic and Phenotypic Correlations for Traits of Chickens written by Terry B. Kinney and published by . This book was released on 1969 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:
