Haematological changes associated with porcine haemoparasitic infections in Ibadan, Oyo State, Nigeria
The study was carried out between January and July 2016. Blood samples were obtained from 153 pigs by venipuncture and jugular severance at slaughter. The blood samples were examined for all known hemoparasites detectable by light microscopic examination. Haematimetric indices, complete blood cell count and leukocyte differentials were determined. The level of parasitaemia and changes in blood indices were subjected to statistical analysis across seasons. Trypanosoma brucei and Eperythrozoon suis were the only hemoparasites detected in the blood of pigs during the period of sampling. The prevalence of haemoparasitic infections in sampled pigs was 5.23%. T. brucei contributed 3.9% while E. suis contributed 1.31% to the prevalence. Anaemia (PCV<32) was a consistent and significant finding in all parasitemic samples. Eperythrozoon suis caused more severe anaemia (20±9.89) when compared with Trypanosoma brucei (27±3.03). The anaemia caused by E. suis was mostly microcytic normochromic while T. brucei mostly caused normocytic normochromic anaemia. Mild leucopenia was observed in eperythrozoonosis while a moderate lymphocytosis was observed in T. brucei infections. It was observed that in spite of intense chemoprophylaxis and other control measures employed, we still have persistent infections with Eperythrozoon sp and Trypanosomes in our pig population. Further studies should be carried out to detect the possibility of drug resistance by some of these circulating hemoparasites in the pig industry. Attempts should also be made to control the vectors of these parasites which are usually abundant during the rainy season and may be responsible for the higher prevalence recorded during this period.
Keywords: Porcine, Infection, Haemoparasites, Haematological changes, Nigeria