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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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References

REFERENCES

Alexander, G. 1961. Temperature regulation in the new-born lamb. III. Effect of environmental temperature on metabolic rate, body temperatures, and respiratory quotient. Aust. J. agric. Res. 12: 1152–1174.CrossRefGoogle Scholar
Alexander, G. and McCance, I. 1958. Temperature regulation in the new-born lamb. I. Changes in rectal temperature within the first six hours of life. Aust. J. agric. Res. 9: 339–347.CrossRefGoogle Scholar
Fleet, I. R., Linzell, J. L. and Peaker, M. 1972. The use of an auto-analyzer for the rapid analysis of milk constituents affected by subclinical mastitis. Br. vet. J. 128: 297–300.CrossRefGoogle Scholar
Gibb, M. J. and Penning, P. D. 1972. The effects of environmental temperature and feeding pattern on the performance of artificially-reared lambs fed cold milk substitute. Anim. Prod. 15: 177–182.Google Scholar
Hartmann, P. E., Trevethan, P. and Shelton, J. N. 1973. Progesterone and oestrogen and the initiation of lactation in ewes. J. Endocr. 59: 249–259.CrossRefGoogle ScholarPubMed
Heap, R. B., Silver, Ann and Walters, D. E. 1981. Effects of pregnancy on the febrile response in sheep. Q. Jl exp. Physiol. 66: 129–144.CrossRefGoogle ScholarPubMed
Johansson, I. 1952. Studies on udder evacuation in dairy cows. II. The amount and composition of the residual milk after normal milkings. Ada Agric. scand. 2: 82–102.CrossRefGoogle Scholar
Linzell, J. L. 1967. The effect of very frequent milking and of oxytocin on the yield and composition of milk in fed and fasted goats. J. Physiol, Lond. 190: 333–346.CrossRefGoogle ScholarPubMed
Linzell, J. L. and Peaker, M. 1974. Changes in colostrum composition and in the permeability of the mammary epithelium at about the time of parturition in the goat. J. Physiol., Lond. 243: 129–151.CrossRefGoogle ScholarPubMed
Martal, J. and Djiane, J. 1977. Mammotrophic and growth promoting activities of a placental hormone in sheep. J. Steroid Biochem. 8: 415–417.CrossRefGoogle ScholarPubMed
Nicoll, C. S., Talwalker, P. K. and Meites, J. 1960. Initiation of lactation in rats by nonspecific stresses. Am. J. Physiol. 198: 1103–1106.CrossRefGoogle ScholarPubMed
Noble, R. C., Steele, W. and Moore, J. H. 1970. The composition of ewe's milk fat during early and late lactation. J. Dairy Res. 37: 297–301.CrossRefGoogle Scholar
Noble, R. C., Steele, W. and Moore, J. H. 1971. The plasma lipids of the ewe during pregnancy and lactation. Res. vet. Sci. 12: 47–53.CrossRefGoogle Scholar
Panaretto, B. A. and Vickery, Marion R. 1970. The rates of plasma cortisol entry and clearance in sheep before and during their exposure to a cold, wet environment. J. Endocr. 47: 283–285.Google ScholarPubMed
Thompson, G. E. 1980. The distribution of blood flow in the udder of the sheep and changes brought about by cold exposure and lactation. J. Physiol., Lond. 302: 379–386.CrossRefGoogle ScholarPubMed
Thomson, E. M., Snoswell, A. M., Clarke, P. L. and Thompson, G. E. 1979. Effect of cold exposure on mam- mary gland uptake of fat precursors and secretion of milk fat and carnitine in the goat. Q. Jl exp. Physiol. 64: 7–15.CrossRefGoogle Scholar