Premilking Stimulation Effects on Milking Performance and Oxytocin and Prolactin Release in Cows
| Autor: | Ronald C. Gorewit, W.G. Merrill, David Wilson, R. Sagi |
|---|---|
| Rok vydání: | 1980 |
| Předmět: |
endocrine system
medicine.medical_specialty Stimulation Oxytocin Milking Protein content Milk yield Pregnancy Lactation Internal medicine Genetics medicine Animals Milk flow Chemistry food and beverages Prolactin Endocrinology medicine.anatomical_structure Cattle Female Animal Science and Zoology hormones hormone substitutes and hormone antagonists Food Science medicine.drug |
| Zdroj: | Journal of Dairy Science. 63:800-806 |
| ISSN: | 0022-0302 |
| DOI: | 10.3168/jds.s0022-0302(80)83009-8 |
| Popis: | For effects on milking performance, 12 Holstein cows were subjected to four stimulation routines: a) no stimulation, b) manual stimulation, c) manual stimulation with delayed milking, and d) intravenous infusion of .75 IU of oxytocin. In an added experiment, effects of the first two treatments on milking performance and release of oxytocin and prolactin were measured. Milk yield, fat, and protein content were not affected by any treatment. Machine-on times were shorter and peak and average milk flow rates higher for manually stimulated and oxytocin infused cows. Concentrations of oxytocin and prolactin in sera at resting were 5.25 μ U/ml and 16.5ng/ml. Differences between mean peak concentrations of oxytocin (16.6 and 16.0 μ U/ml) and prolactin (28.1 and 27.5ng.ml) for stimulated and unstimulated cows were small. Mean oxytocin concentration in stimulated cows peaked at 2min compared with 5min for unstimulated cows. No difference in time of prolactin release was detected. The timing of oxytocin release, rather than maximal concentration, could be the most important factor affecting milking. |
| Databáze: | OpenAIRE |
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