Farmer M, Roland D A, Brake J, Eckman M K
Poult Sci. 1983 Mar;62(3):459-64. doi: 10.3382/ps.0620459.
Dry matter and calcium content of the digestive tract were determined on two groups of broiler breeders during a 24-hr period. The individually caged hens were fed either ad lib or restricted to 122 g of feed during a 4-hr feeding period each day from 0700 to 1100 hr. The hens received artificial light from 0700 to 2300 hr. On Day 14 of the feeding program a total of 100 hens, 10 from each group, were necropsied at selected intervals (0700, 1100, 1900, 2300, 0300 hr), and the contents of the various segments of the digestive tract and feces were collected and analyzed for dry matter and calcium. The calcium analysis also included any endogenous excretions and, therefore, absorption values are apparent. Hens restricted to 122 g feed per day had only 51.7% of the dry matter and 64.2% of the calcium consumed during the 4-hr feeding period remaining in the digestive tract at 1100 hr. By 2300 hr only 20.6% of the feed and 28.1% of the calcium remained. Hens had only approximately 14% (14.2 g) of their total dry matter intake and 16% (.70 g) of the calcium available for absorption from 0300 hr. The ad lib group, with an average intake of 171 g feed per day, had consumed only 26% of their daily feed intake by 1100 hr. Fifty-five percent of the dry matter consumed and 22% of the calcium remained in the digestive tract at 1100 hr. It was concluded that broiler hens restricted to morning feeding do not maintain a constant and equal metering of dry matter or calcium from the crop into the digestive tract throughout a 24-hr period.
在24小时内测定了两组肉种鸡消化道的干物质和钙含量。单独笼养的母鸡要么自由采食，要么每天在07:00至11:00的4小时喂食期内限制采食122克饲料。母鸡在07:00至23:00接受人工光照。在喂食计划的第14天，每组选取10只母鸡，共100只，在选定的时间间隔（07:00、11:00、19:00、23:00、03:00）进行剖检，收集消化道各段内容物和粪便，分析干物质和钙含量。钙分析还包括任何内源性排泄物，因此，吸收值是表观值。每天限制采食122克饲料的母鸡，在11:00时消化道中仅留存4小时喂食期内所采食干物质的51.7%和钙的64.2%。到23:00时，仅留存20.6%的饲料和28.1%的钙。从03:00时起，母鸡可用于吸收的干物质仅占其总干物质摄入量的约14%（14.2克），钙占16%（0.70克）。自由采食组平均每天采食171克饲料，到11:00时仅采食了其日采食量的26%。11:00时，消化道中留存了所采食干物质的55%和钙的22%。研究得出结论，限制在上午喂食的肉种鸡在24小时内无法维持从嗉囊到消化道的干物质或钙的持续且等量计量。
