The effect of feed and water withdrawal on body weight and carcass characteristics of molted turkey breeders
1993
Lilburn, M.S. | Nestor, K.E. | Stonerock, R. | Wehrkamp, T.
In Experiment 1, turkey breeder hens from a randombred control line (RBC1) and a subline of RBC1 selected for increased egg production (E line) were exposed to one of four molting treatments: 1) decreased photoperiod and a shift from a breeder diet to holding diet, Control; 2) decreased photoperiod and no feed on Days 1, 2, 4, and 5, No Feed; 3) decreased photoperiod and no water on Days 1 and 2, No Water; 4) decreased photoperiod and a combination of Treatments 2 and 3, No Feed or Water. Control hens continued to lay following the molt but hens in each of the other treatments ceased egg production. Each feed withdrawal treatment resulted in a nonsignificant decrease in BW immediately postmolt, whereas hens in the Control and No Water treatments exhibited no change or a slight increase in postmolt BW. In both lines, the No Water treatment resulted in an increase in the relative amount of abdominal fat and in E-line hens this treatment also increased relative liver weight. The relative weight of the oviduct was significantly decreased by the No Feed and No Feed or Water treatments compared with the Control and No Water treatments. The loss in oviduct weight was accompanied by a significant decrease in oviductal protein concentration with no change in dry matter content. In Experiment 2, commercial turkey hens were deprived of feed for 7 days with ad libitum access to water. There were no differences in BW at the start of the molt (PRE) in comparison to 14 days following a return to ad libitum feeding (POST). In comparison to the PRE sampling, liver weight was increased and abdominal fat and oviduct weights were decreased at the POST sampling. At second cycle photostimulation, BW and liver weight were increased compared with the PRE sampling whereas abdominal fat did not change. The oviduct did not return to premolt size until 28 days following second cycle photostimulation.
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