Evaluation of molt induction to body weight loss of fifteen, twenty, or twenty-five percent by feed removal, daily limited, or alternate-day feeding of a molt feed.
Postmolt egg production variables were compared among hens induced into molt by feed removal, by limited daily feeding of a low-density and low-energy molt feed at 22.8 g per hen, or by limited alternate-day feeding at 45.5 g per hen, until approximate body weight loss of 15, 20, and 25% was obtained. Hens were housed two per cage (25.4 x 45.7 cm) in a house of environmental design, and photoperiod was reduced to 8 h during the 28-d molt period. When target body weight loss was obtained, packed cell volume was determined and hens were maintained on 45.5 g/d of 1.2% calcium prelay feed through the 28-d molt period. Egg production and mortality were recorded daily; egg weight, egg specific gravity, body weight, and feed intake were recorded at 4-wk intervals postmolt. Packed cell volume of hens molted by feed removal (36.4%) was higher (P < .01) than that of alternate-day (34.1%) or daily limited (33.6%) hens. Hens that lost 25% of their body weight had higher packed cell volume (36.3%) than hens that had body weight loss of 20% (34.4%) or hens that lost 15% (33.4%). Postmolt mortality and egg production were not different (P > .05) as a result of molt induction method or percentage body weight loss. At the 4th wk postmolt, body weights were 50 and 57 g heavier for hens that had lost 15% body weight than those that lost 25 or 20%, respectively, and egg production was negatively linearly related to body weight loss.(ABSTRACT TRUNCATED AT 250 WORDS)
Buhr
R J
RJ
Department of Poultry Science, University of Georgia, Athens 30602-2772.
Cunningham
D L
DL
D000818:Animals; D002645:Chickens / Q000502:physiology*; D004435:Eating; D005241:Feathers / Q000502:physiology*; D005260:Female; D005508:Food Deprivation / Q000502:physiology*; D010058:Oviposition / Q000502:physiology*; D013997:Time Factors; D015431:Weight Loss / Q000502:physiology*