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引言对放牧牛采食量的间接估计有赖于对每日排粪量和采食日料消化率的估测。粪量可通过喂入稳定指示剂(如 Cr_2O_3)、收集具代表性的粪样和测定粪中指示剂的浓度来估测。日料消化率可通过用改良的外科手术法人工取得牧草样品,或通过以前建立的粪便成份与日料消化率的关系式来估测。英国草地研究所(1961)和 Gorbett(1977)已介绍过测定采食量的程序。本文报道近来对几种测定技术的比较。
INTRODUCTION Indirect estimates of feed intake of grazing cattle depend on estimates of daily fecal excretion and feed digestibility. The amount of manure can be estimated by feeding a stable indicator (such as Cr 2 O 3), collecting representative fecal samples, and determining the concentration of indicator in feces. The digestibility of Japanese material can be estimated by obtaining the forage sample artificially by a modified surgical method or by using the relationship between the previously established stool composition and the digestibility of the Japanese material. The British Grassland Institute (1961) and Gorbett (1977) have introduced procedures for the determination of feed intake. This article reports recent comparison of several assay techniques.