Forestomach and whole tract digestibility for lactating dairy XXXX as influenced by feeding frequency.

@entity6135 @entity72434 @entity1568 @entity4336 @entity1460 @entity62 @entity291
Three lactating Holstein @entity291 , averaging 510 kg and fitted with T-type duodenal cannulae in the proximal duodenum, were in a 3 X 3 Latin-square experiment to measure digestion in forestomachs and whole tract of feed @entity1568 and neutral detergent fiber components as influenced by frequency of feeding. @entity291 were fed one diet containing 65% chopped grass legume hay, 26% cracked @entity4336 , and 8% @entity1460 meal. Mixed ration was fed either once daily, four times daily, or the concentrate portion of the diet was fed once daily and the forage portion four times. Ytterbium, as @entity72434 , was included with diets to allow calculation of flow rates of @entity62 . Assayed ratios of @entity1568 to @entity6135 in ruminal bacteria and duodenal digesta or fecal bacteria and feces were used to calculate duodenal and fecal bacterial @entity1568 flows respectively. Ratios of @entity1568 to @entity6135 in ruminal and fecal bacteria averaged 4.15 and 2.38 g/mmol. Apparent digestibility of organic matter in the forestomachs and whole tract averaged 43.7 and 66.4%. Forestomach and whole tract digestibility of cellulose, hemicellulose, and lignin averaged 56.1, 52.0, 14.7, and 58.7, 58.5, and 16.8. Bacterial @entity1568 flows averaged 255 and 91 g/day at the duodenum and in the feces. Bacterial @entity1568 yield in the rumen averaged 36.6 g/kg organic matter apparently digested in the forestomachs. Frequency of feeding had no effect on almost all measures and components of rumen and whole tract metabolism and digestion. For these intakes, frequency of feeding had little effect on feed intake and nutrient utilization.
