title: The potential of monensin for body weight control and ad libitum feeding of broiler breeders from day-old to sexual maturity.
abstract: A total of 180 male and 360 female day-old Indian River broiler breeder chicks were randomly allocated to 18 floor pens in an open-sided pullet brooding and growing house. The birds were subjected to six growing systems that were a combination of three levels of monensin (100, 300, and 400 ppm) and two levels of starter crude protein (CP) (14 and 18% CP) in a randomized complete block design. The basal diets were formulated to be isocaloric, containing 2920 kcal ME/kg. Birds fed 100 ppm of monensin were feed restricted and served as controls, while birds fed 300 or 400 ppm of the drug were fed ad libitum from day-old to sexual maturity. The parameters determined were biweekly individual body weights, feed consumption, internal organ weights, bone and serum mineral composition, and mortality to 21 weeks of age. In general, birds fed high levels of monensin plus ad libitum feeding from day-old were more variable in body weight compared to the feed-restricted controls. In the females, high levels of monensin in the diet were associated with significant reductions in body weight, even with ad libitum feeding, to 21 weeks of age. Male birds fed 300 ppm of the drug were significantly heavier than the feed-restricted controls but were still within the range recommended at this age. High levels of monensin in the diet were associated with a significant reduction in cumulative ad libitum feed consumption compared to the feed-restricted controls.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000375:Aging; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002118:Calcium / Q000097:blood; D002645:Chickens / Q000254:growth & development*; D004032:Diet; D005663:Furans / Q000494:pharmacology*; D006400:Hematocrit; D008274:Magnesium / Q000097:blood; D008985:Monensin / Q000494:pharmacology*; D012741:Sexual Maturation; D012964:Sodium / Q000097:blood
chemical_list: D005663:Furans; D008985:Monensin; D012964:Sodium; D008274:Magnesium; D002118:Calcium