Designing laboratory marmoset housing: What can we learn from urban marmosets?

How to house animals in captivity, so as to maximise their level of well-being, is one of the greatest practical challenges facing animal welfare scientists. Laboratory animal housing can, necessarily, be very restrictive in terms of the facilities being offered to the animal inhabitants due to experimental protocol restrictions. One method of trying to design better laboratory animal housing, in this case for marmosets (a commonly housed primate species), has been to model their housing on behavioural and other characteristics expressed by the species in the wild. Here, an alternative model has been proposed for the design of laboratory marmoset housing: the behaviour and ecology of urban marmosets. Urban marmosets may make a better model than wild marmosets, because they live in a human-designed and highly populated world; therefore, the decisions, choices and compromises that they make already take into account their interactions with the human world. For more than six years we have been studying the behaviour, ecology and other biological aspects of black-tufted marmosets (Callithrix penicillata), which live wild in the city of Belo Horizonte (Minas Gerais, Brazil). The behaviour and ecology of these urban marmosets have provided insights into animal husbandry and enclosure design, plus they have shown how important human–marmoset interactions can be for animal well-being. For example, our studies have shown that marmosets do not engage in human contact in the morning period; thus, suggesting, in terms of husbandry, that in laboratories at this is a time of day they should be given more ‘privacy’. In terms of enclosure design, data presented strongly suggest the need to provide natural vegetation within enclosures as even urban marmosets have obligate relationships with trees. In conclusion, the study of urban marmosets has provided a number of important insights into how the well-being of their laboratory counterparts could be improved.