Why might continuous pair or trio mating systems be used?

Continuous pair or trio mating systems are used primarily to reduce animal stress associated with isolation. Many laboratory animals, especially social species, can experience increased anxiety and stress when housed alone. Social interaction is vital for their well-being, as it mimics their natural living conditions. By allowing animals to live in pairs or trios, they can engage in social behaviors, which can lead to improved welfare and better overall health.

The use of such mating systems can also have benefits for breeding and genetic studies, but the primary motivation in this context pertains to the reduction of isolation-induced stress. It's essential for laboratory animals to have the opportunity to interact socially, as this can positively impact breeding success and the viability of the offspring.

While achieving maximum production in minimum time, eliminating all potential fighting, and improving genetic diversity are certainly relevant factors in breeding strategies, the key rationale behind the use of continuous pair or trio mating systems specifically centers on enhancing the welfare of the animals by minimizing the stress associated with being solitary.