(3) Goat Explanation: Some livestock (and people) tolerate heat better than others. Sheep and goats tend to be less susceptible to heat stress than swine, cattle, llamas, and alpacas. Hair sheep usually tolerate heat better than wooled sheep. This is why they are often used for training and trialing herding dogs. Fat-tailed sheep are also more heat tolerant. The European sheep breeds are usually the least heat-adaptive because they tend to have shorter bodies and legs, short, thick ears, tight skin, and dense fleeces.