Ewe performance, colostrum yield and serum progesterone concentration of single, twin and triplet bearing ewes fed silage

Abstract

There are conflicting data in the literature on the effects of litter size on colostrum production. Shubber et al.,(1979a) reported highest colostrum production in triplet bearing ewes compared with ewes carrying singles or twins. Other researchers (Hall et al.,1989; Shubber et al.,1979b) agree that ewes producing twins yield most colostrum. Hall et al., (1989) also reported that progesterone concentrations before and after parturition increased with litter size and Hartmann et al.,(1973) found that progesterone withdrawl is a prerequisite for lactogenesis and the onset of copious milk secretion. The objective of this experiment was to evaluate the performance of single, twin and triplet bearing ewes in relation to ewe performance, progesterone concentration, quantity and quality of colostrum.Single (Tl, n=35), twin (T2, n=25) and triplet (T3, n=29) bearing oestrous synchronised ewes of mixed lowland breeds (mainly Suffolk cross, greyface and halfbred), were selected following winter shearing and pregnancy scanning in December.