East Coast fever immunisation field trial in crossbred dairy cattle in Hanang and Handeni districts in northern Tanzania

Abstract

East Coast fever (ECF) causes considerable mortality and production losses in the Tanzania smallholder dairy sector and limits the introduction of improved dairy breeds in areas where the disease is present. The infection and treatment method (ITM) was adopted by smallholder dairy farms for ECF immunisation in Hanang and Handeni districts of Tanzania. This study recorded incidence rates for ECF and other tick-borne diseases (TBDs) for ECF-immunised and non-immunised cattle between 1997 and 2000. Approximately 80% of smallholder households from both sites (n = 167) participated in this longitudinal study, with immunisations carried out at the request of the livestock owners. Efficacy of ITM for preventing ECF cases in these crossbred dairy cattle was estimated at 97.6%, while that for preventing ECF deaths was 97.9%. One percent of the cattle developed clinical ECF as a result of immunisation. Since ECF immunisation permits a reduction in acaricide use, an increase in other TBDs is a potential concern. Sixty-three percent of farmers continued to use the same acaricide after immunisation, with 80% of these reducing the frequency of applications. Overall, 78% of farmers increased the acaricide application interval after immunisation beyond that recommended by the manufacturer, resulting in annual savings in the region of USD 4.77 per animal. No statistical difference was observed between the immunised and non-immunised animals in the incidence of non-ECF TBDs. However, immunised animals that succumbed to these diseases showed fewer case fatalities. ITM would therefore appear to be a suitable method for ECF control in Tanzania's smallholder dairy sector.

Epidemiology of Increasing Hemo-Parasite Burden in Ugandan Cattle

“…These are transmitted by Boophilus decoloratus ticks, and mechanical transmission during herd vaccinations has been reported [14] [15] and Babesia bigemina vectored by Boophilus decoloratus has got a wide geographical distribution in the tropics [16]. Generally, tick-transmitted diseases such as Babesiosis and Theileriosis are of economic importance globally [17]- [19]. HP are a major threat to food security especially among the livestock dependent communities within the Sub Saharan Africa [6] [20].…”

“…In Kenya, intensive/semiintensive smallholder systems [30] were characterized by different management practices at the farm, agroecological level as well as grazing systems [4]. Consequently, they show varying ECF prevalence, incidence and ECF-specific morbidity and mortality rates and Kenya has recently approved ECF vaccination [17] in all production systems, thus farm management can improve on the outcomes of HP burden [31].…”

An Ad/MVA vectored Theileria parva antigen induces schizont-specific CD8+ central memory T cells and confers partial protection against a lethal challenge

“…Tanzania, for protection of cattle. 44 , 45 Substantial evidence indicates that cytotoxic CD8 + T lymphocytes induced by the ITM vaccine are crucial for protecting the animals against the T. parva parasite. Therefore, induction of CD8 + T lymphocytes is an important parameter to consider in the development of subunit vaccines towards ECF.…”

A review of recent research on Theileria parva : Implications for the infection and treatment vaccination method for control of East Coast fever

“…Handeni (coastal) districts in Tanzania resulted in annual savings of US$ 4.77 per animal due to increased acaricide application intervals (Lynen et al, 2012). Despite the potential benefits highlighted by this pilot study, adoption of ITM has to date been relatively limited in the small dairy sector.…”

“…However, even in cross‐bred dairy systems, where the economies of scale due to the smaller numbers of animals (3–7) kept are less than in pastoralist systems, the intervention is potentially profitable, since the cost of treatment is much higher at approximately US$ 40 per animal. Field trials in two ecologically distinct small dairy production systems in Hanang (highland) and Handeni (coastal) districts in Tanzania resulted in annual savings of US$ 4.77 per animal due to increased acaricide application intervals (Lynen et al., ). Despite the potential benefits highlighted by this pilot study, adoption of ITM has to date been relatively limited in the small dairy sector.…”