Animal Science

The St. Croix White sheep is well known for its unique characteristics of heat tolerance, parasite resistance, and maternal instincts; however, growth performance remains lower than that of other meat breeds such as Dorper. The Animal Science program is developing a crossbreed between St. Croix White sheep and Dorper, taking into consideration the incidence of twins and triplets, heat stress tolerance, parasite resistance, and growth performance.

Exposure to heat stress during sheep gestation directly impacts fetal development and, as a consequence, offspring performance, negatively impacting the market. This project involves identifying the growth performance consequences and stress indicators of maternal heat stress in purebred and crossbred sheep (St. Croix White and St. Croix White/Dorper).

St. Croix White sheep under heat-stress conditions show lower respiratory rates and rectal and vaginal temperatures than other breeds, indicating that they are highly tolerant. The Animal Science program is identifying and validating molecular markers for heat tolerance in St. Croix White sheep raised under heat-stress conditions.

Livestock production in the Caribbean is under heat stress year-round, and breeding during months of extreme environmental conditions can negatively affect offspring growth performance. A group of St. Croix White sheep and St. Croix White x Dorper crossbred sheep is part of a study evaluating the effect of breeding in spring, summer, and fall on offspring growth performance.