The effects of maedi-visna virus infection on productivity in ewes

摘要: Abstract A total of five data sets obtained from four separate sheep flocks were used to evaluate the effects subclinical maedi-visna virus infection (as determined by serological procedures) on productivity in ewes. In general, with had a detrimental effect productivity. Infection resulted reduction conception rates, odds an infected ewe conceiving being only approximately 0.67 times those non-infected ewe. For ewes which did conceive, there was no number lambs born. The birth weights born middle-aged (3–4 years) 3–6% lower than same age. There very little apparent younger (1–2 and older (5 + ewes: some factors may have biased these results are discussed. Lamb at 25–50 days age appeared be reduced but not statistically significant.