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Lactogenesis in ewes exposed to neutral and cold environmental temperatures during the last week of gestation

Published online by Cambridge University Press:  02 September 2010

G. E. Thompson  and
Jane A. Goode
G. E. Thompson
Affiliation:
ARC Institute of Animal Physiology, Babraham, Cambridge CB2 4AT
Jane A. Goode
Affiliation:
ARC Institute of Animal Physiology, Babraham, Cambridge CB2 4AT
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Abstract

Five ewes, with a wool depth of approximately 5 mm, were placed in a neutral (20 + 2°C) environmental temperature on day 139 of pregnancy, and five similar ewes were placed in a cold (0±2°C) temperature. They remained in these environments until their lambs were 8 days old. Samples of udder secretions, when present, and right-atrial blood were taken from the ewes at 12-h intervals.

Milk from ewes in the neutral environment had a high fat concentration for a brief period after parturition, before the full development of lactose secretion occurred.

In ewes exposed to the cold environment, plasma cortisol concentration was increased during the 2 days before parturition. Cold exposure had no effect on the onset of milk lactose secretion but increased the concentration of fatty acids in milk during the period −0·5 to +4·5 days relative to parturition.

Type
Research Article
Information
Animal Production , Volume 32 , Issue 3 , June 1981 , pp. 245 - 250
Copyright
Copyright © British Society of Animal Science 1981

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