Feed intake and milk yield responses to shearing in Pleven Blackhead sheep with different levels of production
Keywords:
Sheep, shearing, feed intake, milk yieldAbstract
The effects of shearing on feed intake and milk yield was studied in local Pleven Blackhead breed of sheep kept in a shed. Ten lactating ewes were subdivided into two groups, of five ewes each, according to their daily milk production, a high level group (HL) and a low level group (LL), and shorn at the end of March. Measurements were made for 6 days before shearing and for 15 days thereafter. Ewes were fed a ration of chopped hay administered ad libitum and concentrate and were hand milked twice daily at approximately 0800 h and 1800 h. Shearing did not cause considerable change in feed intake. Daily MY fell gradually throughout the observation in both groups owing to advancing of lactation rather than treatment which effect was short-tem. Average for the week after shearing mean MY in HL and LL sheep dropped by 7.2% and 13.1%, respectively, compared to the pre-shearing levels. The observed reduction in daily yield predominantly was at the expense of morning yield, whereas the afternoon one remained almost constant throughout the study. The results suggest that the MY response to shearing may be ascribed to the differences in the capacity for homeorhetic regulation of nutrient partitioning in sheep with different levels of production.
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