Jacquemet N, Prigge EC. Effect of increased postmilking prolactin concentrations on lactation, plasma metabolites, and pancreatic hormones in lactating goats.
J Dairy Sci 1991;
74:109-14. [PMID:
2030165 DOI:
10.3168/jds.s0022-0302(91)78150-2]
[Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Six lactating dairy goats were utilized in a replicated 3 x 3 Latin square design to examine the effect of increased postmilking prolactin concentrations on lactational performance. Thirty minutes after each milking, either placebo or pituitary-derived ovine prolactin at 2 mg/h or 4 mg/h was infused via jugular cannula for 2 h. Goats were housed in a controlled environment at 19 degrees C and a cycle of 16 h light and 8 h dark. Mean plasma prolactin concentrations after milking were increased 100 and 180% for 2 and 4 mg/h prolactin infusion, respectively. Milk yield was slightly but significantly increased by 2 mg/h prolactin infusion compared with placebo and 4 mg/h prolactin infusion. However, milk composition and yields of milk components were not influenced by treatments. No differences in dry matter intake, digestibility of the diet, or N retention were observed. Circulating concentrations of glucose, nonesterified fatty acids, insulin, and glucagon were not altered.
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