Bovine Tuberculosis in Zambian Wildlife

Bovine tuberculosis is known to occur in wildlife species in Zambia. Of those infected, the Kafue lechwe (Kobus leche kafuensis) is a maintenance host, thus sustaining the infection with spread back to cattle.

Bovine TB was diagnosed in Kafue lechwe for the first time in 1954 in the Lochinvar National Park, which is located within the Kafue Basin. It was estimated that on the southern bank of the Kafue flats, BTB was annually responsible for the death of at least 20% of the lechwe (Gallagheretal. 1972). Arecent study has shown a BTB prevalence of 27.7% in the Kafue lechwe (Munyeme et al. 2010a, b). This high prevalence poses a potentially high risk of transmission of M. bovis to livestock, to other wildlife, and to members of the local communities (Malama et al. 2013a, b, c).

The resident population of African buffaloes (Syncerus caffer) in the Kafue basin appears to be free from BTB (Munang’andu et al. 2011). However, the results of the single study done to detect BTB in them are unreliable because of the small number of animals tested and also because primarily young buffaloes that were less likely to be infected with BTB and intended for translocation were tested.

The difference in the occurrence of BTB in lechwe and buffaloes sharing the same ecosystem is probably because of the differences in their interaction with cattle. Buffaloes normally do not come into direct contact with cattle as do lechwe. Within this context, cattle keepers and herdsmen in the Kafue basin report that cattle are never seen to go close to buffaloes, and vice versa, yet lechwe and cattle are regularly observed grazing together (Fig. 23.2).

Fig. 23.2 Cattle and Kafue lechwe grazing side by side in the Kafue basin, Zambia

DNA molecular typing supports the occurrence of bidirectional transmission of the infection between cattle and Kafue lechwe in this area, as similar M. bovis isolates, containing spoligotype SB0120 (SIT 482), occur in Kafue lechwe and in cattle. This is the only spoligotype detected so far in Kafue lechwe in the Kafue Basin indicating that it is highly conserved in Kafue lechwe and in livestock in this area.

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