Rodents cause serious adverse effects on farm production due to destruction of food, contamination of feed, and circulation of diseases. The extent of damage or the diseases spread will depend on the type of rodents that invade the farm. This study was conducted in order to find out the species of rodents that infest poultry farms around Mafikeng, North West Province of South Africa. The study was part of a broader project that was investigating Salmonella vectors in the poultry farms around the province. The study trapped 154 rodents from selected farms and used the Cytochrome oxidase subunit 1 (COI) and the Cytochrome b (Cyt-b) barcoding genes for species identification. Two rodent pest species, namely, Rattus rattus (the black rat) and Rattus tanezumi (the Asian Rat/Asian House Rat) were identified. A total of 99 (64.3%) were identified as Rattus rattus and 55 (35.7%) were Rattus tanezumi. Between the two target genes, Cyt-b gene was only able to identify 40 (25.97%) of the total samples while COI was more efficient and amplified all the samples and thus was a better target gene for this kind of identification. The two rat species identified are known vectors of serious diseases; thus their presence should be regarded as an indication of high risk for diseases. Despite having been detected in the country before, finding R. tanezumi as the second largest rat species in the area was unexpected since this species is known to be indigenous to Asia.

Chickens have been implicated in most Salmonella disease outbreaks because they act as carriers of the pathogen in their gut. There are over 2500 serotypes of Salmonella that have been reported worldwide and 2000 of these serovars can be found in chickens. The main objective of this study was to determine the Salmonella serotypes found in poultry farms around Mafikeng district, South Africa. Salmonella was identified according to the guidelines of the International Organization for Standardization (ISO) (ISO 6579:2002) standard techniques. Faecal samples were collected and analysed for Salmonella using conventional cultural methods and polymerase chain reaction targeting the 16S Ribosomal Deoxyribonucleic acid (rDNA) gene for Salmonella identification. Out of 130 presumptive Salmonella isolates determined by urease and triple sugar iron tests, only 46 isolates were identified as Salmonella serotypes of which S . Typhimurium was the most frequent with 18 (39.1%), followed by S . Heidelberg with 9 (19.6%), S. bongori with 7 (15.2%), S . Enteritidis with 6 (13.0%) and both S. Paratyphi B and S . Newport with 3 (6.5%) each. Seven virulence genes including inv A 100%, spy 39%, hil A 9%, mis L 30%, sdf I 13%, orf L 11% and spi C 9% were detected from these Salmonella isolates in this study. The presence of these virulence genes indicates high pathogenicity potential of these isolates which is a serious public health concern because of zoonotic potential of Salmonella .

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