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Metabolic adaptations in goat mammary tissue during long-term incomplete milking

Published online by Cambridge University Press:  01 June 2009

Colin J. Wilde ,
David R. Blatchford ,
Christopher H. Knight  and
Malcolm Peaker
Colin J. Wilde
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
David R. Blatchford
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
Christopher H. Knight
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
Malcolm Peaker
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
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Summary

Lactating goats were milked incompletely in one gland and normally in the other gland twice daily for 24 weeks. Yields of the incompletely milked glands were adjusted so that a calculated 100 ml milk remained in the gland at the end of milking. On average this residual volume was greater by 7·6% of the total milk volume than that left after normal milking and was 25·9% greater than the capacity of the alveoli. After 24 weeks, the weekly milk yield of the incompletely milked gland was 23·8% lower than that of the other gland (P < 0·001) when expressed in relation to cell number. The metabolic capacity of secretory cells in the two glands was measured in serial tissue biopsies. Two weeks of incomplete milking had no effect on enzyme activities or metabolic fluxes in the incompletely milked gland, but after 24 weeks the activities of several key enzymes were significantly lower in this gland. This was associated with a reduced rate of synthesis of total protein and casein in expiants freshly prepared from the tissue. The rate of lactose synthesis also tended to be lower in expiants from the incompletely milked gland. Secretory cell number in the two glands was similar at the end of incomplete milking. The data indicate that incomplete milking over a long period caused partial secretory cellular involution via a local chemical feedback mechanism in the gland.

Type
Original Articles
Information
Journal of Dairy Research , Volume 56 , Issue 1 , February 1989 , pp. 7 - 15
Copyright
Copyright © Proprietors of Journal of Dairy Research 1989

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References

REFERENCES

Barnes, M. A., Kazmer, G. W. & Pearson, R. E. 1986 Influence of milk frequency and sire selection on residual milk and milking rate. Journal of Dairy Science 68 (Suppl. 1) 269–270Google Scholar
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 140 237–244CrossRefGoogle ScholarPubMed
Blatchford, D. R. & Peaker, M. 1982 Effects of frequent milking on milk secretion during lactation in the goat: relation to factors which limit the rate of secretion. Quarterly Journal of Experimental Physiology 67 303–310CrossRefGoogle ScholarPubMed
Blatchford, D. R. & Peaker, M. 1983 Effect of decreased feed intake on the response of milk secretion to frequent milking in goats. Quarterly Journal of Experimental Physiology 68 315–318CrossRefGoogle ScholarPubMed
Ebendorff, W., Hartmann, K., Kram, K., Morchen, U. & Dorge, I. 1984 The effect on milk yield and udder health of omitting stripping: 2nd lactation. Monatshefte für Veterinärmedizin 39 577–579Google Scholar
Ebendorff, W., Kram, K., Michel, G. & Ziesack, J. 1987 Machine stripping, milk yield and udder health – results of long-term experiments over 4 lactations. Milchwissenschaft 42 23–25Google Scholar
Elliott, G. M. 1961 The effect on milk yield of three times a day milking and of increasing the level of residual milk. Journal of Dairy Research 28 209–219CrossRefGoogle Scholar
Henderson, A. J., Blatchford, D. R. & Peaker, M. 1983 The effect of milking thrice instead of twice daily on milk secretion in the goat. Quarterly Journal of Experimental Physiology 68 645–652CrossRefGoogle ScholarPubMed
Henderson, A. J. & Peaker, M. 1987 Effects of removing milk from the mammary ducts and alveoli, or of diluting stored milk, on the rate of milk secretion in the goat. Quarterly Journal of Experimental Physiology 72 13–19CrossRefGoogle ScholarPubMed
Knight, C. H. & Peaker, M. 1984 Mammary development and regression during lactation in goats in relation to milk secretion. Quarterly Journal of Experimental Physiology 69 331–338CrossRefGoogle ScholarPubMed
Labarca, C. & Paigen, K. 1980 A simple, rapid and sensitive DNA assay procedure. Analytical Biochemistry 102 344–352CrossRefGoogle ScholarPubMed
Linzell, J. L. 1955 Some observations on the contractile tissue of the mammary glands. Journal of Physiology 130 257–267CrossRefGoogle ScholarPubMed
Linzell, J. L. & Peaker, M. 1971 The effects of oxytocin and milk removal on milk secretion in the goat. Journal of Physiology 216 717–734CrossRefGoogle ScholarPubMed
Michel, G., Ziesack, J., Ebendorff, W. & Kram, K. 1986 Effect of omission of stripping of cows' udders. Wissenschaftliche Zeitschrift der Karl-Marx-Universität Leipzig, Mathematische-Naturwissenschaftliche Reihe 35 307–313Google Scholar
Parkash, S. & Jenness, R. 1968 The composition and characteristics of goats' milk: a review. Dairy Science Abstracts 30 67–87Google Scholar
Peaker, M. & Blatchkord, D. R. 1988 Distribution of milk in the goat mammary gland and its relation to the rate and control of milk secretion. Journal of Dairy Research 55 41–48CrossRefGoogle Scholar
Singh, N. & Dave, B. K. 1985 Effect of milking systems on cross-bred cattle. Indian Journal of Animal Production and Management 1 34–36Google Scholar
Wilde, C. J., Addev, C. V. P., Casey, M. J., Blatchford, D. R. & Peaker, M. 1988 Feed-back inhibition of milk secretion: the effect of a fraction of goat milk on milk yield and composition. Quarterly Journal of Experimental Physiology 73 391–397CrossRefGoogle ScholarPubMed
Wilde, C. J., Calvert, D. T., Daly, A. & Peaker, M. 1987 a The effect of goat milk fractions on synthesis of milk constitutents by rabbit mammary explants and on milk yield in vivo. Biochemical Journal 242 285–288CrossRefGoogle Scholar
Wilde, O. J., Henderson, A. J. & Knight, C. H. 1986 Metabolic adaptations in goat mammary tissue during pregnancy and lactation. Journal of Reproduction and Fertility 76 289–298CrossRefGoogle ScholarPubMed
Wilde, C. J., Henderson, A. J., Knight, C. H., Blatchford, D. R., Faulkner, A. & Vernon, R. G. 1987 b Effects of long-term thrice-daily milking on mammary enzyme activity, cell population and milk yield in the goat. Journal of Animal Science 64 533–539CrossRefGoogle ScholarPubMed
Ziesack, J., Michel, G., Ebendorff, W. & Metzlaff, U. 1986 The effect of omitting stripping on the weight and histology of udders from cows. Monatshefte für Veterinärmedizin 41 196–198Google Scholar