Infectious causes of small ruminant mortality in Kenya: A review

Abstract

Small ruminant production systems in Kenya are briefly described. The types of study reporting small ruminant mortality rates, and the large range of values found, are documented and discussed. It was noted that reports from arid and semiarid areas greatly outweigh the number of reports from higher rainfall areas and that more data on mortality before weaning than at any other age are available. Indeed there was only sufficient evidence to draw conclusions regarding pre-weaning mortality rates from arid and semiarid areas, which appear to vary, between locations and from year to year, from 10 to 30% in lambs and from 20 to 30% in kids. Differences in mortality between sheep and goats, and singles compared to twins are discussed. The following infectious causes of mortality were reported in the literature reviewed: tick-borne diseases, including Nairobi sheep disease and heartwater, trypanosomiasis, fasciolosis, pneumonia, capripox, helminthosis, coccidiosis and enterotoxaemia. This review of the literature indicates that the majority of recorded small ruminant deaths are disease-related and that respiratory and intestinal diseases are the most important infectious causes. The quality and value of the available data, the design of on farm studies and the general requirements for animal health and production information in planning livestock development are discussed. Based on the deficiencies in current knowledge, recommendations for future research are made.