Impact of temperature and humidity on the prevalence of diseases in captiveThryonomys swinderianus(Grasscutter) colony in the University of Ghana, Accra, Ghana

Abstract

A study was carried out to determine the prevalence of diseases in a captive breeding colony of grasscutters (Thryonomys swinderianus) of various age groups and in different seasons from February, 2012 to June, 2014. The Grasscutters were maintained in the Department of Animal Science, College of Agriculture and Consumer Sciences, University of Ghana, Legon, Accra, Ghana. The diseases were diagnosed based on clinical history, clinical signs, and symptoms prior to death, lesions observed after postmortem examination of dead animals and isolation and identification of causal agents. A total of 29 dead and sick animals were examined from inside and outside of the campus. Among the diseases, wound infection was found to be the most fatal and constituted 44% of total deaths followed by deathin cages due to acute congestion of lungs, which constituted 33% of total deaths. Enterobacter cloacae was found to be the main causal agent of deaths in the cages. Of the dead in cages, 50% were males, of which 10% were lethargic and unable to move before death and 5% had malocclusion. Among the females found dead in the cages, 5% were pregnant. In general, the highest number of deaths was recorded from January to April and then decreased from May-August. There were no deaths in September. However, there was steady increase from October to December. The results indicated that there was a significant relationship between the deaths of Grasscutter with the ambient temperature and less efficient thermoregulatory mechanisms in the Grasscutter that that triggers deaths and injury in these animals.