Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-19T10:45:46.319Z Has data issue: false hasContentIssue false

A quantitative analysis of mammary glands of dairy heifers reared at different rates of live weight gain

Published online by Cambridge University Press:  01 June 2009

Roger D. Harrison
Affiliation:
Agriculhiral Research Council, Institute for Research on Animal Diseases, Compton, Newbury RG16 ONN, UK
Ian P. Reynolds
Affiliation:
Agriculhiral Research Council, Institute for Research on Animal Diseases, Compton, Newbury RG16 ONN, UK
William Little
Affiliation:
Agriculhiral Research Council, Institute for Research on Animal Diseases, Compton, Newbury RG16 ONN, UK

Summary

The mammary glands of conventionally reared cows, never exceeding a live weight gain (LWG) of 0·74 kg/d, weighed 39% more and contained 68% more secretory tissue than glands of rapidly reared animals grown at 1·1 kg/d. In 11-month-old heifers reared at 3 rates of LWG (L, 0·57; M, 0·76 and H, 1·18 kg/d) gland weight was related to LWG, but dissected mammary parenchyma was heavier in animals on treatment L than on treatment H and followed a quadratic relationship. Parenchymal composition on treatment H was correlated to both age and body weight at puberty. No similar trend was observed in treatments L and M although group L animals had more ductal tissue and less fat than those of group M. Heifers from treatment L were reared during pregnancy at either 0·68 or 0·84 kg/d LWG (treatments LL and LH respectively) and heifers from treatment H at 0·58 kg/d (treatment HL). Total gland weight was unaffected by treatment, but the percentage by weight of secretory tissue in the gland in treatment HL was less than for treatments LL and LH. These experiments confirm that mammary development is permanently impaired by high rates of LWG in the first year of life. There was no impairment of mammary development in heifers reared moderately in the first year and more rapidly during pregnancy.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1983

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Amir, S. 1974 Early breeding of dairy heifers – prospects and limitations. 25th Annual Meeting of European Association of Animal Production, Copenhagen (Conference reprint)Google Scholar
Amir, S. & Kali, J. 1974 Influence of plane of nutrition of the dairy heifer on growth and performance after calving. Dairy Science Handbook 7 183190Google Scholar
Amir, S. & Kali, J. 1975 Some topics for future research. In The Early Calving of Heifers and its Impact on Beef Production pp. 274280 (Ed. Tayler, J. C.), Brussels: Commission of the European CommunitiesGoogle Scholar
Amir, S., Kali, J. & Volcani, R. 1968 Influence of growth rate on reproduction and lactation in dairy cattle. In Growth and Development of Mammals pp. 234256 (Eds Lodge, G. A. and Lamming, G. E.). London: Butterworths. (Easter School in Agricultural Science, University of Nottingham, no. 14, 1967)Google Scholar
Gordon, H. & Sweet, H. H. 1936 A simple method for the silver impregnation of reticulum. American Journal of Pathology 12 545551CrossRefGoogle ScholarPubMed
Larsen, J. B., Foldager, J., Sejrsrn, K. & Klausen, S. 1982 [Milk yield and longevity in cows in relation to age at first calving 1. 2 vs. 2½ years in Danish Red], Beretning fra Statens Husdyrbrugs forsog no. 523, 58 ppGoogle Scholar
Little, W. & Harrison, R. D. 1981 Effects of different rates of live weight gain during rearing on the performance of Friesian heifers in their first lactation. Animal Production 32 362 (abstr.)Google Scholar
Little, W. & Kay, R. M. 1979 The effects of rapid rearing and early calving on the subsequent performance of dairy heifers. Animal Production 29 131142Google Scholar
Little, W., Mallinson, C. B., Gibbons, D. N. & Rowlands, G. J. 1981 Effects of plane of nutrition and season of birth on the age and body-weight at puberty of British Friesian heifers. Animal Production 33 273279Google Scholar
Ministry of Agriculture, Fisheries and Food, 1982 Rearing autumn born Friesian dairy heifers to calve at two years. Agricultural Development and Advisory Service Booklet 2379, Alnwick, Northumberland: MAFFGoogle Scholar
Roy, J. H. B., Gillies, C. M. & Shotton, S. M. 1975 Factors affecting first oestrus in cattle and their effects on early breeding. In The Early Calving of Heifers and its Impact on Beef Production pp. 128 142 (Ed. Tayler, J. C.), Brussels: Commission of the European CommunitiesGoogle Scholar
Sejrsen, K., Huber, J. T., Tucker, H. A. & Ackers, R. M. 1982 Influences of nutrition on mammary development in pre- and post-pubertal heifers. Journal of Dairy Science 65 793800CrossRefGoogle Scholar
Sinha, Y. N. & Tucker, H. A. 1969 Mammary development and pituitary prolactin levels of heifers from birth through puberty and during the oestrous cycle. Journal of Dairy Science 52 507512CrossRefGoogle Scholar
Swanson, E. W. 1960 The effect of rapid growth with fattening of dairy heifers on their lactational ability. Journal of Dairy Science 43 377387CrossRefGoogle Scholar
Swanson, E. W. & Poffenbarger, J. F. 1979 Mammary gland development of dairy heifers during their first gestation. Journal of Dairy Science 62 702714CrossRefGoogle ScholarPubMed
Weibel, E. R., Kistler, G. S. & Scherle, W. F. 1966 Practical stereological methods for morphometrie cytology. Journal of Cell Biology 30 2338CrossRefGoogle Scholar