- Author : Ann Laster McDonald
- Publisher :
- Release : 2008
- ISBN :
- Pages : pages
Morphological and Physiological Changes in Laying Hens in Various Stages of Non feed Withdrawal Molt
Download or read book Morphological and Physiological Changes in Laying Hens in Various Stages of Non feed Withdrawal Molt written by Ann Laster McDonald and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Molting is a natural occurrence in the Avian species that can include a period of fasting. Animal rights groups view the long-accepted standard industry practice as inhumane. Based on influences from these groups and the recommendation of its scientific committee, United Egg Producers (UEP) requires members of its Animal Care Certified Program use a non-feed withdrawal molting program, even though the morphological and physiological effects of this method have not been studied in depth and the existing literature provides contradictory results. Research regarding how to induce a non-feed withdrawal molt has been performed using feed that is nutrient deficient or contains an additive to cease egg production. Studies have shown subsequent egg production to be comparable to hens molted using feed withdrawal. This study was designed to determine the morphological and physiological changes that occur in a non-feed withdrawal molt. Two hundred hens divided into 40 groups of 3 birds each were molted in a staggered pattern so that the morphological and physiological effects of non-feed withdrawal molt could be measured with identical environmental and housing variables. Data was divided into 5 sections including Control (n=5), Start (n=7), Mid-Molt (n-7), Near End (n=7), and Over (n=15). Internal organs were examined and measured. Corticosterone levels were measured to determine if non-feed withdrawal molting causes less stress to hens. Pertinent blood parameters including cholesterol, glucose, O2, CO2, hemoglobin, and hematocrit were also measured. Results indicate internal organ weight changes due to non-feed withdrawal molt were as expected. Decreases in the oviduct length, ovary weight, follicle weight, and follicle number indicate regression of the reproductive tract. No differences (P