Molecular detection of Pneumocystis carinii from lung tissues of pigs slaughtered in south-east Nigeria
Keyword : Piggery, interstitial pneumonia, Pneumocystis carinii f. sp., PCR-detection, Nigeria
Author(s) : Elomba C. Chidozie And Okonkwo I.F
Abstract : ABSTRACT Fungus Pneumocystis carinii f. sp. suis infects respiratory system of pigs (Sus domesticus), causing interstitial pneumonia and associated economic losses due to its detrimental effects on pig’s growth, food conversion and carcass condemnations. Difficulty in identification in tissue samples has led to a dearth of information on P. carinii infection in African pigs. We used established robust and sensitive nested PCR method to detected P. carinii f. sp. suis DNA in lung tissues, determined its infection prevalence in pigs, and evaluated infection risk regarding sex of pig, location, and farming system. A cross-sectional epidemiological study on lung tissues of 200 pigs, sampled randomly from swine-abattoirs in five States in Nigeria, was conducted between May and September 2019. All identifiable samples were frozenstored before DNA extractions done within 48 hours of collection, with established protocol for gSYNCTM DNA Extraction Kit version 05.08.17. The PCR-amplified products occurred when a nested PCR with primers amplifying the internal transcribed spacer was used on lung tissues to specifically obtain amplification of diagnostic fragment of 550 bp. Mean prevalence of P. carinii f. sp. suis infection was 22.0%. No statistical significant differences were found among the groups of animals, their sex, state of origin, farming production systems and the infection, as the significance level found for all statistical tests was higher than 0.05. Consequently, no statistical evidence was found for correlation between the variables studied and the P. carinii f. spp. suis infection. This paper calls for further studies on evolution P. carinii f. sp. suis infection in Nigeria, and its impact in pork production.