Tsavo Mobile Veterinary Unit - February 2010

The caseload for the Unit is still low

The caseload for the Unit is still low. There is still abundant forage and water for the animals in the parks that has reduced incidences of animal injuries from conflicts with people and poaching for bush meat. Some parts also received some good rains towards the end of February which further enhances availability of the two resources which their scarcity during the dry seasons escalates conflicts and bush meat poaching when the animals move from the parks into community lands and ranches to search for them.

This month we did post-mortem examinations of two elephants at the Ithumba elephant orphanage that died from unknown causes. We associated the deaths from a Gastro-intestinal tract (GIT) problem. There was haemorrhagic enteritis of the small intestines accompanied by overproduction of mucous. The GIT was empty and the intestines distended by gas.  This was manifested before death by distended abdomen and signs of abdominal pain (colic). Elephants have sensitive digestive system. We could not identify the cause of the problem. However, we collected stomach and intestinal contents for toxicological analyses. We also advised the keepers to withhold feeding barley that can cause digestive problems especially to young elephants that are still dependent on milk. De-worming was recommended every three months following observations of worms whose infestation was however not alarming.

Most of February was spent doing rinderpest disease surveillance in the Tsavos. This is part of the national obligation to the Global Rinderpest Eradication Program (GREP) under the World Organisation for Animal Health (OIE) to eradicate the disease by 2010. The surveillance is undertaken annually in critical areas where wildlife interact highly with the pastoral livestock particularly those from the Somali ecosystem. Somalia remains a gap in the disease eradication following the collapse of the national government in 1990. This has resulted to the horn of Africa being the only remaining suspected part of the world where the rinderpest virus still circulates. The African Union-Inter African Bureau for Animal Resources (AU-IBAR) supports the surveillance in various African countries in the horn of Africa.  The last surveillance in the Tsavos was done in November 2008. the current surveillance was supposed to have been done the same time last year. However due to some logistical difficulties, this was not possible.

The surveillance entails immobilisation of susceptible wildlife species and collection of blood samples for antibody analyses at the international rinderpest reference laboratories (Pirbright UK and CIRAD France), the Eastern Africa regional reference laboratory (KARI Muguga Kenya) and the national reference laboratory (VIL Kabete). Susceptible species include the lesser kudu, buffalo, eland and giraffe, which during previous outbreaks in mid and late 1990s suffered highest mortalities especially in Tsavos. Other species that have been shown to have positive antibody titres but no clinical disease include the warthog and waterbucks. The buffalo is a good sentinel for the detection of the disease and is preferred where present. The other species particularly the lesser kudu and the eland are difficult to sample because of large flight distances.

The buffalo being abundant in the Tsavos was the species mostly sampled during the current exercise. Sixty-two buffaloes ranging between 1.5 and 6 years (average 3 years) were sampled. One giraffe aged about 3 years was sampled at Sheikh Salim ranch near Mackinnon road where no buffalo herds were found. Normally, animals between >1 and <6 years are sampled to avoid complications of maternal immunity (passed from mother to calf through milk) and life-long immunity (acquired if an animal recovers from the disease.) The last virus circulation in the Tsavo was detected in 2001. The areas sampled were those that experience livestock encroachment from the ranches leased out to the Somali pastoralists for fattening their livestock. In Tsavo East, these were Voi and Irima, Ngutuni/Ndara plains, Kanderi, Satao and Dika plains as well as Bachuma and Sala (south and north of Galana river). In Tsavo west, we sampled areas around Maktau and Ziwani. We also sampled animals in the ranches namely Sagalla, Sheikh Salim, Galana, Kulalu and Luarenyi. However, livestock have displaced most animals in many ranches and those present were shy and difficult to get.

Report by Dr. David Ndeereh

The Mobile Veterinary Unit operated by The David Sheldrick Wildlife Trust working with The Kenyah Wildlife Service and funded by Vier Pfoten