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Lack of correlation between milk glucose concentrations and rates of milk production in the rat

Published online by Cambridge University Press:  01 June 2009

Murray R. Grigor ,
Janet M. Carrington ,
Peter G. Arthur  and
Peter E. Hartmann
Murray R. Grigor
Affiliation:
Department of Biochemistry, University of Otago, Dunedin, New Zealand
Janet M. Carrington
Affiliation:
Department of Biochemistry, University of Otago, Dunedin, New Zealand
Peter G. Arthur
Affiliation:
Department of Biochemistry, University of Western Australia, Nedlands, WA 6009, Australia
Peter E. Hartmann
Affiliation:
Department of Biochemistry, University of Western Australia, Nedlands, WA 6009, Australia
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Summary

Concentrations of lactose, α-lactalbumin (α-la), glucose and glucose-6-phosphate were measured in milk obtained from rats under conditions where the rates of milk production varied from 0 to 2·6 g/h. In the milk from rats fed a low protein diet where milk production was 0·9 g/h, the concentration of α-la was 1·5 mg/ml, being significantly lower than that in the milk of control rats at 2·9 mg/ml and where the rate of milk production was 2·6 g/h. No differences were detected in the glucose concentrations. When rats were fed restricted amounts of the control diet and where milk production varied from 0 to 1·7 g/h during the course of the day, no differences in the concentrations of either α-la or glucose were detected. These results suggest that considerable caution must be used in interpreting the significance of milk glucose in the rat.

Type
Original Articles
Information
Journal of Dairy Research , Volume 56 , Issue 1 , February 1989 , pp. 37 - 43
Copyright
Copyright © Proprietors of Journal of Dairy Research 1989

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