Skip to main content Accessibility help
×
Home

In-vivo magnetic resonance imaging studies of mammogenesis in non-pregnant goats treated with exogenous steroids

  • Paul A. Fowler (a1), Christopher H. Knight (a2) and Margaret A. Foster (a1)

Summary

Mammogenesis and lactation were induced in five multiparous, non-pregnant goats by treatment with oestrogen and progesterone for 11 d, followed by dexamethasone for 3 d. Reserpine was administered during the last 5 d. All five goats lactated, although milk yield was less than had been achieved in previous natural lactations. Mammary development was assessed in vivo, using magnetic resonance imaging. Although parenchyma volume increased by more than 6-fold overall, only 25% of this increase occurred during steroid treatment. Most development took place after the cessation of treatment, when milking commenced. Maximum size was not achieved until week 8 of the induced lactation, and was only 70% of normal parenchyma volume. After 18 weeks lactation the activities of three key milk synthetic enzymes were very similar to values previously found in natural lactations, and secretion efficiency (milk production per unit volume of parenchyma) was also similar to that of natural lactations. We conclude that the lower than normal milk yields were associated with incomplete proliferation of mammary tissue, rather than inadequate differentiation of individual secretory cells.

Copyright

References

Hide All
Atheya, U. K. & Sud, S. C. 1989 Short-term hormonal treatment for induction of lactation in repeat-breeding cattle. Indian Journal of Animal Sciences 59 558560
Bauman, D. E., Brown, R. E. & Davis, C. L. 1970 Pathways of fatty acid synthesis and reducing equivalent generation in mammary gland of rat, sow, and cow. Archives of Biochemistry and Biophysics 140 237244
Collier, R. J., Bauman, D. E. & Hays, R. L. 1977 Effect of reserpine on milk production and serum prolactin of cows hormonally induced into lactation. Journal of Dairy Science 60 896901
Cowie, A. T., Cox, C. P., Folley, S. J., Hosking, Z. D., Naito, M. & Tindal, J. S. 1965 The effects of the duration of treatments with oestrogen and progesterone on the hormonal induction of mammary growth and lactation in the goat. Journal of Endocrinology 32 129139
Cowie, A. T., Folley, S. J., Malpress, F. H. & Richardson, K. C. 1952 Studies on the hormonal induction of mammary growth and lactation in the goat. Journal of Endocrinology 8 6488
Cowie, A. T., Knaggs, G. S., Tindal, J. S. & Turvey, A. 1968 The milking stimulus and mammary growth in the goat. Journal of Endocrinology 40 243252
Fleming, J. R., Head, H. H., Bachman, K. C., Becker, H. N. & Wilcox, C. J. 1986 Induction of lactation: histological and biochemical development of mammary tissue and milk yields of cows injected with estradiol-17β and progesterone for 21 days. Journal of Dairy Science 69 30083021
Forsyth, I. A., Byatt, J. C. & Iley, S. 1985 Hormone concentrations, mammary development and milk yield in goats given long-term bromocriptine treatment in pregnancy. Journal of Endocrinology 104 7785
Fowler, P. A., Knight, C. H., Cameron, G. G. & Foster, M. A. 1990 a The use of magnetic resonance imaging (MRI) in the study of goat mammary glands in vivo. Journal of Reproduction and Fertility 89, 359366
Fowler, P. A., Knight, C. H., Cameron, G. G. & Foster, M. A. 1990 b In-vivo studies of mammary development in the goat using magnetic resonance imaging (MRI). Journal of Reproduction and Fertility 89, 367375
Fulkerson, W. J. & McDowell, G. H. 1975 Artificial induction of lactation in cattle by use of dexamethasone trimethylacetate. Australian Journal of Biological Sciences 28 183187
Hart, I. C. & Morant, S. V. 1980 Roles of prolactin, growth hormone, insulin and thyroxine in steroid-induced lactation in goats. Journal of Endocrinology 84 343351
Knight, C. H. & Peaker, M. 1984 Mammary development and regression during lactation in goats in relation to milk secretion. Quarterly Journal of Experimental Physiology 69 331338
Labarca, C. & Paigen, K. 1980 A simple, rapid, and sensitive DNA assay procedure. Analytical Biochemistry 102 344352
Smith, K. L. & Schanbacher, F. L. 1973 Hormone induced lactation in the bovine. 1. Lactational performance following injections of 17β-estradiol and progesterone. Journal of Dairy Science 56 738743
Wilde, C. J., Henderson, A. J. & Knight, C. H. 1986 Metabolic adaptations in goat mammary tissue during pregnancy and lactation. Journal of Reproduction and Fertility 76 289298

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed