Spatial-Temporal Movements of Free Ranging Pigs at the Wildlife-Livestock Interface of Murchison Falls National Park, Uganda: Potential of Disease Control at a Local Scale

Abstract

In many Ugandan rural communities, pigs are generally kept under traditional smallholder systems without basic biosecurity measures in place. In some instances, these systems are at the livestock-wildlife interface, as it is the case in Nwoya district, which is bordered by Murchison Falls National Park (MFNP). This pig system has potential for the maintenance and transmission of pathogens like African swine fever (ASF) between different herds, and also with wild pigs (warthogs and bushpigs). In this paper, we describe the spatial and temporal pattern of the movements of free ranging domestic pigs in a rural setting in Northern Uganda where ASF is endemic. We also determine their use of habitat to highlight the potential interaction hotspots between domestic pigs and between domestic and wild pig populations. We fitted 10 free-ranging domestic pigs owned by different homesteads with GPS harnesses during rainy and dry seasons. The pig home range, daily distance, activity pattern and habitat use were calculated. Our results show that the maximum area covered (MCP 100%) by the pigs varied between 35,965 and 475,077 m2. The core area varied from 1,317 to 50,769 m2. The pigs' home ranges were significantly bigger during the dry season than during the rainy season (Wilcoxon test, W = 22, p = 0.04). The mean full day (24 h) distance was longer in the dry season than in the rainy season (Student test, t = 2.7, p = 0.03). The pigs were mostly located within their own homestead, but they also used other homesteads, grass and crop fields. This study highlights that free-ranging domestic pigs may cover a wide area, especially during the dry season. Interestingly, the home range of pigs from different herds may overlap with areas used by wild pigs which share crops and other resources in this area. This study provides insights into a better understanding of the potential for spread of diseases such as ASF at small-scale and can be used to raise awareness of such risks and to better target implementation of preventive measures.

Assessing the knowledge and practices of smallholder pig farmers and associated risk factors for swine gastrointestinal disorders in Masindi district, Uganda

“…and Zambia (59), among others. Farmers opt for free ranging system because they incur less cost and on labor of feeding and housing such pigs (37). It must be stressed that GIT disorders in pigs are frequently the result of multiple agents and rarely due to the effects of a single pathogen.…”

“…Farmers observed GIT disorders throughout the year, with slightly higher cases in the dry season although this was not signi cant. The relatively higher incidences of GIT disorders in the dry season can be attributed to the changes in agricultural activities and management systems that promote scavenging since there is plenty of crop residues left in the gardens after the harvest (37,38). On the contrary, the farmers restrict pig movement to protect the planted crops from damage by the scavenging pig, during the rainy season (37).…”

“…The relatively higher incidences of GIT disorders in the dry season can be attributed to the changes in agricultural activities and management systems that promote scavenging since there is plenty of crop residues left in the gardens after the harvest (37,38). On the contrary, the farmers restrict pig movement to protect the planted crops from damage by the scavenging pig, during the rainy season (37). Yet, other farmers continue to release their pigs to graze on abundant green herbage around the homesteads during the rainy season, which may explain the sustained high occurrence of GIT disorders throughout the year.…”

Seroprevalence of African swine fever in pigs in Lere and Zaria Local Government Areas of Kaduna State Nigeria

“…In sharp contrast to Zaria LGA, the pigs at Lere LGA had been reared for long time by many families and many were on free range system of management. The free range system in pig production is a major factor responsible for increased risk of ASF (Payne et al, 2021). ASF has been included among notifiable animal disease according to the World Animal Health Organization (WOAH).…”

An Updated Review of Ornithodoros Ticks as Reservoirs of African Swine Fever in Sub-Saharan Africa and Madagascar

“…Another study provided evidence of the occurrence of a sylvatic tick-warthog cycle in Lake Mburo NP [ 78 ]. Other authors have documented potential contacts between warthogs and domestic pigs at the edge of Murchison Falls NP and possible links with ASF outbreaks [ 79 , 80 ]. However, these studies are scattered in space and time, and there is no clear and updated information about the distribution of the sylvatic cycle in Uganda.…”