Large White turkey breeder hens were used to evaluate the effect of three different levels of physical feed restriction on subsequent reproductive performance. The feed treatments were: 1) fed ad libitum throughout the study (CC), 2) feed-restricted from 16 to 24 wk (CR), 3) feed-restricted from 3 to 16 wk (RC), and 4) feed-restricted from 3 to 24 wk (RR). Feed restriction was implemented so that restricted-fed hens (RC and RR) achieved a 45% reduction in BW as compared to CC hens at 16 wk. From 16 to 24 wk, feed was allotted to RR and CR hens to maintain a slight increase in BW. At the completion of the respective restriction periods, hens were gradually returned to ad libitum feeding. At 30 wk of age, hens were photostimulated for a 20-wk summer season egg production cycle. Hens receiving RC and RR treatments laid significantly more eggs than did CC and CR hens for the first 5 wk of lay. However, once the house temperature increased to 26.7 to 29.4 C during 6 to 10 wk of lay, egg production of all hens decreased, resulting in a significant decrease in cumulative egg production for RR and RC hens compared to CC and CR hens. Egg and poult weights were less for RC and RR hens compared to those from CC and CR hens. In conclusion, age of breeder, season of implementation, and length of physical feed restriction have significant effects on the reproductive performance of turkey breeder hens.
Large White turkey breeder hens were used to evaluate the effect of three different levels of physical feed restriction on subsequent body and carcass composition. The four feed treatments were 1) ad libitum fed throughout the study (CC), 2) feed restricted from 16 to 24 wk (CR), 3) feed restricted from 3 to 16 wk (RC), and 4) feed restricted from 3 to 24 wk (RR). Feed restriction was implemented so that RC and RR hens achieved a 45% reduction in BW compared to CC hens at 16 wk. From 16 to 24 wk, feed was allotted to RR and CR hens to maintain a slight increase in BW. At the completion of each restriction period, hens were gradually returned to ad libitum feeding. At 30 wk, hens were photostimulated for a 20-wk summer season egg production cycle. Restricted fed hens had increased moisture levels at 16 and 30 wk and decreased fat levels at 16, 30, 39, and 54 wk (P < or = 0.05). Absolute and relative weights of the pectoralis major muscle were greater in hens fed ad libitum through 43 wk (P < or = 0.05). There were no differences in the number of maturing yellow follicles due to treatment. However, restricted fed hens had higher peak egg production during early lay but decreased subsequent and cumulative egg production. Changes in egg production were associated with changes in breast muscle weight. Prolactin levels were greater in hens in-production compared to hens out-of-production; however, there were no differences due to feed treatment. In conclusion, further research on quantitative feed-restriction programs, which result in body weight reductions as described in this study, should address specific physiological and nutritional requirements and not be implemented as general programs.
Large White turkey breeder hens were fed ad libitum (CC), feed-restricted from 16 to 24 wk (CR), feed-restricted from 3 to 16 wk (RC), or feed-restricted from 3 to 24 wk (RR). Feed restriction was implemented so that RC and RR hens achieved a 45% reduction in BW compared to CC hens at 16 wk. From 16 to 24 wk, feed was allotted to RR and CR hens to maintain a slight increase in BW. At the completion of each restriction period, hens were gradually released back to ad libitum feeding. At 30 wk of age, hens were photostimulated for a 20-wk summer season egg production cycle. Mean BW for all treatments were different (P < or = 0.05) at 16 and 30 wk. At the end of lay, hens on treatment CR were not different in BW from treatment CC hens, and treatment RR hens were not different in BW from treatment RC hens. Hens on treatment RR had the greatest BW gain and feed consumption leading into the production cycle. All treatment hens lost BW from the time of first egg until 47 wk of age. Hens on treatment CC lost significantly (P < or = 0.05) more relative BW (%) than those in any other treatment. Coefficient of variation for flock uniformity was similar for all treatments at time of photostimulation. At the end of the study, cumulative feed consumption was significantly less for restricted treatments: 86.5, 83.1, 75.8, and 70.7 kg/hen for treatments CC, CR, RC, and RR, respectively.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.