Fox M T, Gerrelli D, Pitt S R, Jacobs D E
Department of Veterinary Pathology, Royal Veterinary College, London, UK.
Vet Res Commun. 1991;15(2):127-33. doi: 10.1007/BF00405144.
Non-esterified fatty acid (NEFA) levels in housed, 3-month-old calves were monitored in two experiments designed to establish (i) the effect of diet and time of sampling in relation to feeding on blood levels; and (ii) the relationship between appetite and plasma NEFA in animals on chopped hay. In the first experiment, a significant drop in NEFA levels was recorded after feeding. Furthermore, the NEFA levels of calves maintained on concentrate were significantly lower than those on hay throughout the post-feeding period. In the second study, a significant negative correlation was established between NEFA levels and intake of chopped hay in (i) ad-lib-fed calves infected with the abomasal nematode Ostertagia ostertagi; (ii) worm-free animals pair-fed with those in group (i); and (iii) ad-lib-fed worm-free calves. Regression analysis of raw and transformed data from all three groups combined also yielded significant correlations. It is suggested that the measurement of blood NEFA may be a useful indirect indicator of feed intake in conditioned housed calves offered hay diets.
在两项实验中监测了圈养的3月龄犊牛的非酯化脂肪酸（NEFA）水平，这两项实验旨在确定：（i）日粮和采样时间与采食时间对血液水平的影响；以及（ii）采食切碎干草的动物的食欲与血浆NEFA之间的关系。在第一项实验中，采食后记录到NEFA水平显著下降。此外，在采食后的整个期间，以精料饲养的犊牛的NEFA水平显著低于以干草饲养的犊牛。在第二项研究中，在以下几类犊牛中均确定NEFA水平与切碎干草采食量之间存在显著的负相关：（i）感染皱胃线虫奥斯特他线虫的自由采食犊牛；（ii）与第（i）组动物配对饲养的无虫动物；以及（iii）自由采食的无虫犊牛。对所有三组的原始数据和转换数据进行的回归分析也得出了显著的相关性。研究表明，对于提供干草日粮的圈养条件下的犊牛，血液NEFA的测定可能是采食量的一个有用的间接指标。
