Disease and mortalities in selected zoological gardens in Nigeria

Diseases in captive wildlife constitute a major challenge to the function of zoological gardens only second to management. These diseases vary in etiology depending on susceptibility, the environment, and husbandry method used. Exposure to infectious diseases is known to be responsible for the declining figures in wild animal population especially wild felids. Sick or dead animals subjected to laboratory diagnosis, diagnostic imaging, and necropsy from three (3) zoological gardens in Nigeria between 2014 and 2018 were included in this study, while dead animals not subjected to any form of clinical, laboratory, and necropsy diagnosis were excluded. Between 2014 and 2018, carcass submission at the Jos, Kano, and Unilorin zoo comprised wild ungulates, non-human primates, small mammals, reptiles, felids, and aviary from the selected zoological gardens combined. In total, sixty-six (66) cases were studied, and this included a wide variety of animal species. All cases resulted in mortalities distributed across these zoological gardens. Non-infectious conditions accounted for 23% of total cases reported including fractures, nutritional deficiencies, toxicity, and dystocia, among others. Infectious diseases including bacterial, parasitic, and viral were the dominant groups of diseases of captive wild animals in these zoos. Bacterial infections were the most common infectious causes accounting for 41% of the cases. Isolates include Mannheimia haemolytica biotype A serotype 2 (A2), Salmonella spp, and Escherichia coli. While non-infectious causes were responsible for some mortalities either singly or as co-morbidities with bacterial agents, mixed causes accounted for 15% of all the cases. This study enumerates the common diseases, species affected, in wild captive animals in three zoological gardens in Nigeria, making the ation available to clinicians, biologists, pathologists, public health workers, and policy makers.