Livestock Research for Rural Development 26 (2) 2014 Guide for preparation of papers LRRD Newsletter

Citation of this paper

Impact of African Swine fever epidemics in smallholder pig production units in Rombo district of Kilimanjaro, Tanzania

E S Swai and C J Lyimo*

Ministry of Livestock and Fisheries Development, PO Box 9152, Dar-es-Salaam, Tanzania
* District Livestock Office, PO Box 287 Mkuu Rombo, Tanzania


Animal diseases have multiple direct and indirect effects on human livelihood, health and welfare. Animal disease outbreaks also pose significant threats to the profitability of livestock production throughout the world, both from the point of economic impacts of the disease itself and the measures taken to mitigate the risk of disease introduction and control measures applied in the event of an outbreak. A study to evaluate the impact of an African swine fever (ASF) outbreak in smallholder pig units in Rombo district of Kilimanjaro, Tanzania was conducted during the period of October 2013. The study involved 1085 smallholder farmers who owned pigs (n=5322) at different ages and stages of maturity during the period of March to September 2013. Information on the number of pigs owned pre- and post the ASF outbreak was collected through face-to-face interviews, direct farm observations and secondary data were retrieved from various district livestock office reports.

This survey revealed that the pig density in Rombo district was 17/km2 and average herd size to be 5 (range, 1- 57), higher than the national average of 3 (range 2-48). The overall revenue accrued from sales of live pigs and pork between 2005-2012 amounted to Tsh 65 million to 102 million and 257 million to 566 million per annum, respectively. Mortality losses specifically arising from the ASF outbreak were 84% (range 46-97) and on average the number of pigs lost per household was 4 (range 1-50). Translation of such mortality figures into financial terms produces a loss of Tsh 160.632 million, indicating that ASF is a deadly and devastating disease that can disrupt the pig industry and the entire local economy. This study established that small-scale pig production is an important source of livelihood in many households and contributes to the value chain in rural areas of Rombo district. Given the transboundary nature of the disease (fast spreading and respecting no border), the study recommends that, in any future intervention, effort should be directed at the prevention of infection at source; early detection of the disease when it occurs; timely reporting and rapid response by involving a wide range of stakeholders at district, regional, national and international levels. At farm level, good husbandry and biosecurity practices such as confinement of pigs though construction of adequate housing, avoiding contaminated feed and water, appropriate disposal of carcasses, prohibition of slaughter, movement ban, establishment of check points and decontamination procedures using known and proven quality disinfection should be given high priority, as there is currently no vaccine available.

Key words: disease, economics, impact, mortality, outbreak, viral


The report "Agriculture for Development" (World Bank Report 2008)  shows that livestock is the most important non-land asset owned by rural people in developing countries. Livestock are important in supporting the livelihoods of poor farmers, consumers, traders and labourers throughout the developing world. About 85% of the poor depend on agriculture and livestock to a greater or lesser extent (IFAD 2000, ADB 2007). The animals of poor people are particularly vulnerable to disease because of the expense, absence or unsuitability of animal-health and production inputs (Perry and Rich 2011).

In Tanzania, as in other tropical countries, increased production and productivity of pigs (Sus scrofa) is limited among others by the widespread occurrence of vectors and diseases. The losses are incurred in the form of productivity losses, morbidity and mortality. Among the important diseases of pigs, viral diseases are a major constraint, especially African Swine fever (ASF), and particularly in the small-holder mixed intensive and extensive management systems (Penrith et al 2007). African swine fever (ASF), Office International Epizootics (OIE) notifiable, is a highly contagious and deadly hemorrhagic disease of domestic pigs (of all breeds and ages) caused by African swine fever virus (ASFv), a double-stranded DNA virus of the family Asfarviridae and genus Asfivirus. In eastern and southern African countries, the disease occurs through complex transmission cycles involving domestic pigs, soft ticks and wild African pigs, and warthogs (Phaecochoerus africanus), which do not develop signs of disease (Lubisi 2005). In spite of more than 50 years of research, there is no vaccine available against ASF.

Little work has been carried out to assess the socio-economic impact of ASF in different farming systems in different agro-ecological zones in Tanzania. This study which was conducted shortly after the extensive wave of an ASF epidemic, was designed to establish the mortality impact of the disease on small-holder piggery production in Rombo district, Kilimanjaro region, Tanzania.

Materials and methods

Description of study area

Rombo is one of the six districts of Kilimanjaro region of Tanzania. Administratively, the district is divided into 5 divisions, 24 wards and close to 65 officially registered villages (RDSEP 2013). The district population is 261,000 and growth rate is estimated to be 1.4-1.9% per year (URT 2012a, census). The total district land area is 1,440 km2, of which 58% is forest land, 31% land suitable for cultivation, 0.83% land suitable for irrigation and 9.5% land for pasture production. The population density is 471 per km2 of the available land (42%) and average house hold size is 4.4 (URT 2012a, census). The district is located in the eastern slope of Mount Kilimanjaro and lies between latitude 3o 01’ and 3o 09’ South and longitude 37o 28’ and 37o 33’ East, at altitude 800 to 5895 metres above sea level. Long rains fall between mid-March and June while short rains occur November to December. Mean annual rainfall ranges from 500 mm and 1,000 mm. Dry periods are between January and early March; and between August and September. The daily temperature ranges from 18 to 28 oC (RDSEP 2013).

Figure 1: Map of Rombo district (source: district profile report)

The main ethnic groups are Chagga in the highland and Kamba, Kikuyu and Pare on the lowland. Traditionally the Chagga have their homesteads on the highlands or mountain slopes, where, in addition to growing coffee and bananas, they also keep a few livestock, particularly cattle. Other animal species kept include sheep, goats, pigs and poultry. The lowland farms are used mainly for the production of food crops, normally maize, beans and finger-millet.

Description of swine production system in the study area

Mixed crop livestock production is practiced in Rombo. Livestock are managed under the intensive and extensive grazing system. Due to limitation of land for other agricultural activities, pigs are mainly kept under indoor system and primary output is meat and other socio-economic purposes. Type of feeds offered included crop residues, cut grasses and other pastures, kitchen wastes, by-products of locally brewed alcohol. Prior to ASF incursion, pig population in Rombo district was estimated to be 25,000 (URT 2012b).

Survey protocols

Focus group discussion, direct farm observation and face-to-face interview were the procedures used to collect information. Interviews were conducted with all pig owners who lost pigs during the disease outbreak. Other groups of key informants interviewed included division or ward officials and pork traders. Interviews were guided by a list of questions such as number of pigs owned before and after the disease outbreak, financing including pig acquisition model (through cash purchase or through loan from official credit institution or saving scheme such as SACCOS), and perception on income and livelihood loss. Other information was sought from secondary literature sources available from Regional and district profiles.

Data analysis

Data were entered and analysed by Microsoft Excel software. The data were summarised using descriptive statistics such as percentages, means and frequency tables. A comparison of statistical difference between proportions was carried out using the Chi-squared test.

Results and Discussion

Households characteristic and livelihood sources

The most important livelihood sources were reported to be crop farming, livestock keeping, and small scale businesses.The source of the first pig was through cash purchase (92%) from relatives or friends, 0.46% from district development programmes (Tanzania Social Action Fund, TASAF) and few through either church under pig-in-trust (PIT) scheme (0.46%) or loan (6%) from non-governmental organisation (BRAC) or community saving and credit cooperative organization (SACCOs) (1%). Very few households claimed that they acquired pigs from inheritance or dowry. This showed that pig keepers were tilted towards commercial farming rather than traditional pig keeping. In agreement with other studies in Tanzania, pig ownership was dominated by males (91%); very few pigs were owned by females  and private institutions (Karimuribo et al 2011). Despite the fact that farmers kept other animal species such as cattle, goats and sheep, the findings from this study showed that small-scale pig farming was an important source of livelihood and income for a large segment of the+ population in Rombo. Such findings have also been reported in other countries in Africa and Asia (Kagira et al 2010, Costales et al 2007, Lemke et al 2006).

Herd structure

According to National livestock sub census survey of 2012, the Regional (Kilimanjaro) pig density was 9 per km2, with Rombo district having a higher pig density of 17 per km2 compared to other districts; the average household herd size was generally two to five pigs (Wilson and Swai 2013). Results from the survey showed Mashati division as having significantly more households owning pigs in terms of large numbers than other divisions (Table 1). Interviewed pig-keeping households own between 1 and 57 pigs, averaging 5 pigs, higher than the national average of 3 (range 2-48) (URT 2012b). The small flock structure revealed by this survey is in agreement with findings under small–scale farming systems in other developing countries (Ajala et al 2007, Huynh et al 2007). Such structure is an indication that there are relatively few piglets available on-farm as replacement stock for future flock build-up of the piggery units in this area. The possible reasons that may contribute to this observation include movement off farm of young animals in terms of sale of live piglets or high off take rate for sub-adults and adult in the study area. Majority (>90%) of the farmers kept non-descript types of pigs with < 10% keeping cross-breed (mainly local breed and Landrace or Large white) types of pigs.

Table 1: Number of households(HHs) and relatives number of pigs owned before ASF incursion by division


Number of HHs

Number of pigs


 % of total


 % of total































Trends of live pig and pig products trade in Rombo district, 2005-2012

Information retrieved from the district livestock office data base revealed that the volume of live pig and pig products sales over the years to be stable during the years(2005-2007) and sometimes fluctuating particularly during the years 2008-2010 (Figure 2).

Figure 2: Trend of live pig sales from 2005-2012

Assuming a conservative average price of live pig to be US $ 40, and a kilogram of meat of US$2, the overall revenue accrued from sales were on the average about Tsh 125,200,000 million (range 52,176,000 – 165,024,000 million) and 400,349,933 million (range 257,812,000-566,730,000 million) per annum, respectively( I US $ = 1200 Tsh) (Figure 3). These figures exclude cost of sows, weaners and piglets for flock expansion which often has no fixed price. The generated sales and income is of crucial importance to the local economy. Respondents revealed that the accrued income was used for paying school fees, buying household goods and footing medical bills. Some of the other reported uses of pig-derived income included exchanging for other livestock species such as chicken and goats. In line with other studies elsewhere, it is believed that pigs are a tool to enhance household income and food security among vulnerable small-holder resource poor house-holds (Kagira et al 2010; Huynh et al 2007).

Figure 3: Revenue accrued from sales of live pigs and pork from 2005/6 to 2011/12
Mortality due to ASF

Of the 1085 pig keeping households physically visited and interviewed, each claimed to have lost pigs of varied stages of maturity during the period of March to August 2013. On average the number of pigs lost per household was 4 (range 1-50). Overall mortality was 84 % (range 46-97%). Detailed mortality by division is given in Table 2 and Figure 4. The proportion of the households that lost entirely their herd is shown in Figure 4 and the scenario of ASF incursion is shown in Photos 1-3. ASF severity and impact was higher in Usseri, Mengwe and Mashati division. Significant loss was in terms of mortality or the slaughter of animals during attempts at control that occurred in all stage of pigs, from piglet, sub-adults to adults. Piglet mortality depletes the replacing flock hence reduced off-take. Other unaccounted loss was in form of trade restriction, disposing the carcasses, cost of disinfectants and spraying pig sheds. Overall mortality (excluding emergency slaughters) loss of 84 % was quite high in Rombo district as compared to what has been reported elsewhere in Tanzania (Nangona pers comm).

Table 2: Mortality due to ASF



 by division

Proportion of the total

No owned

No died

































Figure 4: Proportion of the households that lost entirely their pig herd (n=1085)

Image1519 060320111640 060320111587
Photo 1a: A typical small scale piggery
unit-before the disease outbreak
Photo 1b: The piggery during the ASF outbreak Photo 1c: The piggery unit after the disease outbreak
Effects on players (value chain analysis) in the pig industry in Rombo

Supportive instruments for pig production in the district include suppliers of feeds (imported from Kenya; hotel or kitchen left overs) and deliverers of regulatory services. Other important service providers include local veterinary supplies and extension services, live pig and pig products traders and piggery unit laborers. In addition, there are numerous, unregistered small slaughter slabs providing pig meat at regular/irregular times for the fresh meat market. The retail pork sector consists of numerous beer bars and barbecue shops that earn a living via sales of roasted pig meat. Besides key players as indicated in the value chain, there are service providers such as credit providers who have to be paid depending on whether the project was supported through loans, transporters and cash providers and others who play several facilitation roles along the commodity chain (Figure 5).

Figure 5: Chain value analysis of impact of ASF

Translation of the losses  into monetary value in the different segments of the value chain could not be made due to the lack of accurate data; however, the upsurge of ASF has lead to the total collapse of these activities which are very vital for the local economy.

This study has highlighted a number of issues that are of major concern in the sustainability of the local pig industry, most importantly the need to implement effective disease control. ASF is a classical transboundary disease [TAD] that does not respect borders and exerts a broader impact on food security, nutrition, health and the environment in addition to the severe financial costs (Nana-Nukechap and Gibbs 1985). As a result and given the nature of the disease and the lack of a vaccine, its containment requires a joint effort between farmers, district, regional, national and international agencies. The basis for ASF control is prevention of infection; early detection of the disease when it occurs; timely reporting and rapid response (Erick et al 2011). The following are some of the most basic measures whenever there is ASF outbreak: confinement of pigs in good standard housing, avoiding contaminated feed and water, appropriate disposal of carcasses, prohibition of slaughter, movement ban, establishment of check points, decontamination and disinfection.


Conflict of interest statement

None of the authors of this paper has a financial or personal relationship with other people or organization that could inappropriately influence or bias the content of the paper.


The authors wish to thank the District Livestock Officers in Rombo district and the Ward Extension Officers in the study areas for the assistance they provided during the field work. We acknowledge the pig keepers, traders, input suppliers who voluntarily participated in this study and provided relevant information regarding themselves and the pig industry.


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Received 13 December 2013; Accepted 10 January 2014; Published 4 February 2014

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