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Little is known in Brazil about milk production of ewes. As wool and meat production have become important activities in the country, an increasing interest in milk production is observed. Thus, the objective of the present work is to evaluate the effect of the use of bypass fat in the diet of Bergamasca dairy ewes on milk production. Eighty ewes were divided into 2 blocks according to parturition and age. Within each block, half of the animals received either one of two treatments: A - balanced diet (concentrate + corn silage) without bypass fat; and B - same diet as in A with added bypass fat (35g/ewe/day). In both blocks, the lambs were kept with their mothers in pasture during daytime and were separated at night. The lambs were returned to their mothers after the morning milking and were weaned at 45 days of age. The ewes were machine-milked starting 48 hours after parturition, once a day, at 7h A.M., for 60 days. Diets were isoenergetic and isonitrogenous, containing 22% CP and 66% TDN on a dry-matter basis. The statistical analysis was performed by means of SAEG 9.0 (System for Statistical and Genetic Analyses). Statistical differences were not observed (P>.05) between treatments for average daily milk production until 45 days; however, after 45 days, treatment B showed a higher (P<.05) milk yield in comparison to A (540 vs 502 g/ewe/day). This result may be attributed to the use of diet with bypass fat, which supposedly provided better absorption of unsaturated fatty acids in the small intestine. [ABSTRACT FROM AUTHOR]

Most of Brazilian breeds present capability for meat or wool production, but it is possible to find animals with dairy properties. Bergamasca ewes, for example, introduced in Brazil in 1940, are raised in the Northeast for meat production. Considering their Italian origin, they could be used for milk production; however, the amount of milk produced by lactation and its characteristics are not well known. In view of this, the objective of the present work, carried out at the Ewe Milk Production Research Unit of the College of Veterinary Medicine and Animal Science of the São Paulo State University (UNESP), is to evaluate the effect of the different management systems on milk production of Bergamasca ewes. Eighty seven ewes were used and submitted to two milk production systems. In the group without lambs, these were separated from their mothers 48h after birth, while, in the mixed group, lambs were kept with their mothers until to 60 days of age, when they were weaned. Both ewes from the group without lambs and from the mixed group were machine-milked for a period of 90 days and milk production was daily measured during the whole experimental period. The statistical analysis was performed by means of the GLM procedure of the Statistical Analysis System (SAS, 1985). Ewes managed in the group without lamb presented higher (P<.05) daily average milk production in comparison to the mixed group. This difference may be explained, in part, by milk injection inhibition during machine-milking. In the beginning of lactation, the absence of a proper sign during machine-milking, which is usually present when females are nursing their lambs, inhibits the release of ocytocin and milk ejection reflex. [ABSTRACT FROM AUTHOR]