title: Genetic and environmental effects on internal parasites, foot soundness and attrition in crossbred ewes.
mesh_terms: D000818:Animals; D003433:Crosses, Genetic; D005260:Female; D005535:Foot Rot / Q000453:epidemiology*; D012756:Sheep / Q000235:genetics / Q000469:parasitology*; D012757:Sheep Diseases / Q000453:epidemiology*; D013045:Species Specificity