Effect of Sex and Pregnancy on Feed Intake Capacity of Growing Cattle
作者:
K.Lønne Ingvartsen,
H.Refsgaard Andersen,
J. Foldager,
期刊:
Acta Agriculturae Scandinavica, Section A — Animal Science
(Taylor Available online 1992)
卷期:
Volume 42,
issue 1
页码: 40-46
ISSN:0906-4702
年代: 1992
DOI:10.1080/09064709209410107
出版商: Taylor & Francis Group
关键词: voluntary dry matter intake;sex differences;prediction of intake;heifers;bulls;steers
数据来源: Taylor
摘要:
The effects of sex and pregnancy on feed intake capacity in growing cattle were studied in an experiment with fifteen bulls, steers and heifers, respectively, and designed with complete randomized blocks. All sexes were fed ad libitum with a complete diet based on chopped straw from three months of age to approximately 520 kg. At live weights below 250 kg heifers had higher feed intake capacities (IC) than bulls, and IC of steers was intermediary. Above 250 kg live weight sex differences in IC were small and not significant. The results support the hypothesis that early maturing animals (heifers and steers) have a higher IC than late maturing animals (bulls) at low live weight. Gestation decreases IC during the last 14 weeks of pregnancy and IC was depressed by 1.5% per week. During the last couple of weeks before calving the depression in IC may be even higher. The depression in IC is due to both physical limitation of the reticulorumen and gastrointestinal tract and hormonal regulation.
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