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Pancreatic insulin responses to exogenous glucose in Friesian heifers of low or high genetic merit for milk-fat yield

Published online by Cambridge University Press:  02 September 2010

G. Q. Xing ,
D. D. S. Mackenzie ,
S. N. McCutcheon  and
B. W. Wickham
G. Q. Xing
Affiliation:
Department of Animal Science, Massey University, Palmerston North, New Zealand
D. D. S. Mackenzie
Affiliation:
Department of Animal Science, Massey University, Palmerston North, New Zealand
S. N. McCutcheon
Affiliation:
Department of Animal Science, Massey University, Palmerston North, New Zealand
B. W. Wickham
Affiliation:
Livestock Improvement Corporation, New Zealand Dairy Board, Hamilton, New Zealand
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Abstract

Two studies were conducted to examine the effects of selection for milk-fat yield on pancreatic responses to exogenous glucose, as measured by circulating insulin concentrations following an intravenous glucose load, in heifer calves. The first study involved 6-month-old Friesian heifers, eight each from the Massey University high breeding index (HBI) and low breeding index (LBI) lines. Average breeding indices (BI) for milk-fat yield of the calves based on ancestry BI were 136 (s.d. 2) and 112 (s.d. 2), respectively. Oestrous cycling of the heifers was controlled by intravaginal insertion of progesterone-impregnated controlled internal drug-releasing devices (CIDRs). Challenges of glucose (0, 75, 150 and 300 mg/kg live weight) and insulin (0, 0·1, 1, and 10 fig/kg live weight) were administered via indwelling jugular cannulas and were followed by serial blood sampling to measure responses. Plasma insulin concentrations immediately following the glucose challenge were significantly (P < 0·05) greater in HBI than in LBI heifers, peak insulin concentrations (above baseline) in the HBI group being approximately twice those in the LBI group. Plasma glucose concentrations were marginally lower in HBI heifers, probably due to the secondary effect of the relatively greater hyperinsulinaemia in this group. Although the exogenous insulin challenge significantly reduced circulating glucose concentrations in all heifers, there was no difference between the lines in the magnitude of insulin-induced hypoglycaemia.

The second study was designed to determine whether insulin responses to an exogenous glucose load were influenced by stage of the oestrous cycle in heifers of the two lines. In this study, eight yearling HBI heifers and eight LBI heifers (with BI of 135 (s.d. 4) and 111 (s.d. 1) respectively) were administered an intravenous glucose load (150 mg/kg live weight) on tivo occasions, the first being after 17 days of CIDR treatment (simulating the luteal phase of the oestrous cycle) and the second 46 h after withdrawal of the CIDRs (when the heifers were expected to be in oestrus). HBI heifers again showed significantly greater circulating insulin concentrations than LBI heifers following the glucose challenge but the magnitude of this effect was not influenced by time relative to CIDR withdrawal. It is concluded that heifers selected for high milk-fat yield have an increased pancreatic response to exogenous glucose which is apparently independent of the stage of the oestrous cycle. This difference may provide a useful means of identifying heifers of superior genetic merit for milk-fat production prior to their first lactation.

Keywords

genetic meritglucoseheifersinsulinprogesterone
Type
Research Article
Information
Animal Production , Volume 56 , Issue 2 , April 1993 , pp. 171 - 178
Copyright
Copyright © British Society of Animal Science 1993

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References

Barnes, M. A., Kazmer, G. W., Akers, R. M. and Pearson, R. E. 1985. Influence of selection for milk yield on endogenous hormones and metabolites in Holstein heifers and cows. Journal of Animal Science 60: 271–284.CrossRefGoogle ScholarPubMed
Costrini, N. V. and Kalkhoff, R. K. 1971. Relative effects of pregnancy, estradiol, and progesterone on plasma insulin and pancreatic islet insulin secretion. Journal of Clinical Investigation 50: 992–999.CrossRefGoogle ScholarPubMed
Flux, D. S., Mackenzie, D. D. S. and Wilson, G. F. 1984. Plasma metabolite and hormone concentrations in Friesian cows of differing genetic merit measured at two feeding levels. Animal Production 38: 377–384.Google Scholar
Gill, J. E. L. and Hafs, H. D. 1971. Analysis of repeated measures of animals. Journal of Animal Science 33: 331–336.CrossRefGoogle ScholarPubMed
Gilmour, A. R. 1985. REG — a generalised linear models program. Miscellaneous bulletin, Division of Agricultural Services, Department of Agriculture, Neiv South Wales, no. 1.Google Scholar
Holmes, C. W. and Wilson, G. F. 1984. Milk production from pasture. Butterworths of New Zealand (Ltd), Wellington, New Zealand.Google Scholar
Kirkwood, R. N., Lapwood, K. R., Smith, W. C. and Anderson, I. L. 1984. Plasma concentrations of LH, prolactin, oestradiol-17β and progesterone in sows weaned after lactation for 10 or 35 days. Journal of Reproduction and Fertility 70: 95–102.CrossRefGoogle ScholarPubMed
Land, R. B., Carr, W. R., Hart, I. C., Osmond, T. J., Thompson, R. and Tilakaratne, N. 1983. Physiological attributes as possible selection criteria for milk production. 3. Plasma hormone concentrations and metabolite and hormonal responses to changes in energy equilibrium. Animal Production 37: 165–178.Google Scholar
McCann, J. P. and Reimers, T. J. 1985. Insulin response to glucose in estrus and diestrous obese and lean heifers. Journal of Animal Science 61: 619–623.CrossRefGoogle ScholarPubMed
Mackenzie, D. D. S., Wilson, G. F., McCutcheon, S. N. and Peterson, S. W. 1988. Plasma metabolite and hormone concentrations as predictors of dairy merit in young Friesian bulls: effect of metabolic challenges and fasting. Animal Production 47:1–10.Google Scholar
MacMillan, K. L., Day, A. M., Taufa, V. K., Barnes, D. R. and Braggins, T. J. 1987. Plasma progesterone concentrations and oestrus or ovulation in heifers treated with a CIDR-type B for at least seven weeks. Proceedings of the Australian Society for Reproductive Biology 19: 61.Google Scholar
MacMillan, K. L., Washburn, S. P., Henderson, H. V. and Petch, S. F. 1990. Effects of varying the progesterone concentration of CIDR inrravaginal devices and multiple CIDR treatments on plasma hormone concentrations and residual hormone content. Proceedings of the New Zealand Society of Animal Production 50: 471–472.Google Scholar
Michel, A., McCutcheon, S. N., Mackenzie, D. D. S., Tait, R. M. and Wickham, B. W. 1991. Metabolic responses to exogenous bovine somatotropin in Friesian cows of low or high genetic merit. Domestic Animal Endocrinology 8: 293–306.CrossRefGoogle ScholarPubMed
Min, S. H., McCutcheon, S. N., Mackenzie, D. D. S. and Wickham, B. W. 1993. Plasma metabolite and hormone concentrations in Friesian calves of low or high genetic merit: effects of sex and age. Animal Production 56: 17–27.Google Scholar
Munro, R. K. 1987. Concentrations of plasma progesterone in cows after treatment with 3 types of progesterone pessaries. Australian Veterinary Journal 64: 385–386.CrossRefGoogle ScholarPubMed
Sinnett-Smith, P. A., Slee, J. and Woolliams, J. A. 1987. Biochemical and physiological responses to metabolic stimuli in Friesian calves of differing genetic merit for milk production. Animal Production 44:11–19.Google Scholar
Woolliams, J. A. and Lovendahl, P. 1991. Physiological attributes of male and juvenile cattle differing in genetic merit for milk yield: a review. Livestock Production Science 29: 1–16.CrossRefGoogle Scholar
Xing, G. Q., Mackenzie, D. D. S. and McCutcheon, S. N. 1991. Diurnal variation in plasma metabolite and hormone concentrations and response to metabolic challenges in high breeding index and low breeding index Friesian heifers fed at two allowances. Neiv Zealand Journal of Agricultural Research 34: 295–304.CrossRefGoogle Scholar
Xing, G. Q., Mackenzie, D. D. S., McCutcheon, S. N., Wilson, G. F. and Flux, D. S. 1988. Plasma metabolite and hormone concentrations in Friesian calves differing in genetic potential for milkfat production. New Zealand Journal of Agricultural Research 31: 159–167.CrossRefGoogle Scholar