Disease management and veterinary interventions

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Our animals within the Reserve have suffered from outbreaks of anthrax (Clegg et al. 2007), rabies (Clegg and Wolhuter 2007), canine distemper, and foot and mouth disease.

The anthrax outbreak in 2004 was particularly severe, with almost 100% of the kudu population being killed. Nyala (68%), bushbuck (48%), roan (42%), waterbuck (44%), wild dog (27%), and hippopotamus (21%) were also badly affected. A total of 906 carcasses were located and disposed of by either burning or burying. In an attempt to control the spread of the disease, 20 roan, 15 black rhinos, 39 white rhinos and five hippos were vaccinated from a helicopter using drop-out darts. In addition, 821 buffalo, 81 waterbuck and two kudus were vaccinated by herding the animals into a capture boma and pole syringing them.

To determine the effectiveness of the different disposal methods, soil samples were collected at 78 sites where carcasses had been burned or buried. Anthrax bacteria were detected in only three of the soil samples, indicating that the disposal methods had been effective in restricting the level of residual contamination.

Between March and June 2007, Malilangwe’s wild dog population was decimated by an outbreak of rabies. Of the 75 individuals known to frequent the reserve, only two survived. One of the packs (originally 21 animals) had been habituated by wildlife cinematographer Kim Wolhuter. This pack was comfortable around Kim’s vehicle, so it was possible to vaccinate and monitor 19 of the animals. The dogs were vaccinated from the vehicle using drop-out darts and were given a booster seven days later. It was possible to keep the dogs near the vehicle during darting by providing two fresh impala carcasses. Dogs affected by rabies tried to feed but their efforts were largely unsuccessful as they appeared to have difficulty swallowing. These animals had the same problem when attempting to drink, and interestingly, they showed no fear of water and were even seen bathing. Other clinical signs of infection included biting branches, repeated rolling, running the side of the mouth along the ground as if trying to remove something, pawing at an open mouth, and nonaggressive nipping of other individuals, especially while resting. During the late stage of infection their stomachs were clearly withdrawn, and they were weak and wobbly. Excessive or frothy saliva was not noted, and the dogs were not aggressive. Despite management’s efforts to save a core population, all but two dogs succumbed. One of the surviving animals had been vaccinated 12 days earlier when it was fitted with a radio collar. This early inoculation may have been the reason it survived.

The severe economic crisis experienced in Zimbabwe post 2000 resulted in a breakdown of veterinary controls in the communal lands surrounding Malilangwe. Resources required to vaccinate domestic dogs against rabies and canine distemper were no longer available and outbreaks of these diseases became common place. To help the situation, Malilangwe provided transport and vaccines to the local government veterinary authorities.

Malilangwe’s Scouts have eliminated snare poaching from the reserve. However, wild dogs and hyenas sometimes leave the reserve and return carrying wire snares. When possible, these animals are immobilised, the snares removed, and their wounds treated.