MATTARAIA, Vania Gomes de Moura and MOURA, Ana Silvia Alves Meira Tavares. Produtividade de ratos Wistar em diferentes sistemas de acasalamento. Cienc. Rural [online]. 2012, vol.42, n.8, pp. 1490-1496. ISSN 0103-8478. http://dx.doi.org/10.1590/S0103-84782012000800026.
Research tests efficiency of three mating systems of rats in animal facilities
Researchers from Universidade Estadual Paulista (UNESP), Botucatu, in São Paulo and of Instituto Butantan, São Paulo, Brazil, verified that temporary polygamous system is an economic alternative to production of Wistar rats (Rattues norvegicus) in big animal facilities, as it respects the precepts of welfare of these animals. The paper was published in Ciência Rural journal, v.42, n.8, of August 2012.
To achieve these results, researchers evaluated three mating systems: permanent monogamous, with a couple permanently maintained in each cage; polygamous permanently, with the two arrays and a male kept permanently in each cage, and polygamous temporarily, in that the male was kept in a cage with two arrays to the certification of each coupling and then was withdrawn, returning the offspring post weaning. The sample contained 69 female 90-day divided in three groups. The researchers evaluated five reproductive cycles per female.
The results show that temporary polygamous system permits weaning of heavier pups. Furthermore, dam mortality was null in this system, which is indicative of animal welfare. The permanently monogamous system enabled the production of a young weaner in less time if compared to polygamous systems, but requires double number of cages and males than the other systems. The polygamous system still presents considerable saving of space and resources.
The polygamous system can be recommended in expansion and production colonies of Wistar rats in animal houses, as it promotes animal welfare. Presenting itself as an efficient technique, the system allows an optimization of the production scale in the animal facilities to meet the demands of scientific experimental models. However, the author Ana Sílvia Moura points out that it needs skilled labor for the identification of mating and for the management of rotation of the males.