Milking performance of dairy ewes fed pellets containing soy hulls as starchy grain substitute

Effect of feeding pellets containing soy hulls (SH) as starchy grain substitute on milking performance was measured in Assaf lactating ewes. Eighty ewes were divided into two equal groups of forty animals each, and fed for eight weeks, one of the two experimental diets. Both diets contained 25% vetch hay and 10% wheat silage served at the feeding lane plus additive of 65% pellets served part on top of roughage in the feeding lane and part during milking. Diets differed only in the composition of the pelleted additive, being either high starch pellets in the control treatment or pellets containing 51% SH as starch replacer in the experimental group. In vitro organic matter digestibility of the two types of pellets was similar, whereas NDF digestibility and NDF content were higher in the SH pellets. The ewes fed the SH pellets demonstrated higher daily DM and NDF intake (2.71 and 1.19 kg/d, respectively) as compared with the control group (2.44 and 0.71 kg, respectively). This was reflected by significantly higher milk yield (2.41 kg/d versus 2.10 kg/d), milk fat content (6.05% versus 5.16%), and milk fat yield (0.15 kg/d versus 0.11 kg/d) in the experimental group as compared with the control ewes. Milk protein yields were similar in both treatments. Data suggest potential advantage of feeding the SH pellets for high producing lactating ewes.