Investigation and treatment of ovine psoroptic otoacariasis.

Background: Psoroptic otoacariasis has been described worldwide and is caused by a mite morphologically indistinguishable from the sheep scab mite Psoroptes ovis. A single treatment of affected sheep with 200 μg/kg of injectable ivermectin is reported to be curative.

Case Report: Psoroptes mites were isolated following treatment with ivermectin, but treatment with moxidectin at 1 mg/kg caused complete cessation of clinical signs.

Genetic susceptibility to infectious disease in East African Shorthorn Zebu: a genome-wide analysis of the effect of heterozygosity and exotic introgression.

Background: Positive multi-locus heterozygosity-fitness correlations have been observed in a number of natural populations. They have been explained by the correlation between heterozygosity and inbreeding, and the negative effect of inbreeding on fitness (inbreeding depression). Exotic introgression in a locally adapted population has also been found to reduce fitness (outbreeding depression) through the breaking-up of co-adapted genes, or the introduction of non-locally adapted gene variants.