Implications of Genotype by Environment Interactions in Dairy Sheep Welfare

Abstract

Small ruminants are the most extensively farmed livestock species in Europe, as a result being extremely exposed to natural hazards which leads to strong interactions between genotype and environment. Aim of the current review was to outline and discuss the main welfare issues and economic implications with regards to the genotype by environment interactions in dairy sheep. Researches concerning the additive genetic effect on milk yield, shown that this accounts only for 10%, while the milk production is 90% influenced by environmental factors, highlighting the major role that management and nutrition play in the dairy production of sheep. Nowadays, dairy sheep breeds (e.g. Eastern Friesian and Lacaune), are being introduced and reared in various countries under an extremely wide range of rearing conditions, without adequate knowledge on their acclimatization to the new specific conditions. It was concluded that a welfare assessment protocol for dairy sheep does not exist up today, moreover, there is a serious lack of data concerning the genetic and environmental factors affecting the welfare status of dairy sheep at farm level under different production systems.

Keywords

• animal welfare
• genotype by environment interactions
• lactating sheep
• lameness
• mastitis