Effect of season on milk temperature, milk growth hormone, prolactin, and somatic cell counts of lactating cattle
Monthly fluctuations in milk temperature, somatic cell counts, milk growth hormone and prolactin of lactating cows were measured in milk samples over a 1 year period. The seasonal patterns in milk temperature, somatic cell count and milk prolactin concentration showed a positive trend with increasing environmental temperatures. Milk growth hormone concentration increased with lactation level and declined significantly during summer heat. Milk temperature and the measured hormonal levels may serve as indicators of the impact of the climatic environment on lactating cattle.
Key wordsCow milk temperature Somatic cell counts Milk growth hormone Prolactin Seasonality
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