Nematode infection depresses humoral immune responses of goats to mycoplasma capricolum subsp. capripneumoniae vaccine antigens

Abstract

Mycoplasma capricolum subsp. capri pneumoniae (Mccp) causes contagious caprine pleuropneumonia (CCPP), a disease of goats characterised with a high morbidity and mortality in non vaccinated goats. The objective of this study was to investigate the impact of nematode infection on humouralimmune responses to Mccp vaccine in goats. Forty (40) goats, aged 9 – 12 months, were randomly allocated to four groups of ten. Group A were orally inoculated with infective stages of nematodes followed by immunization with inactivated Mccp vaccine after 3 weeks. Group B were not inoculated with nematodes but immunized as Group A. Group C were inoculated with infective stages of nematodes but not vaccinated as in A. Group D was neither inoculated nor vaccinated. Clinical observations and records were done daily at 8.30 AM, blood for sera analysis was collected weekly, while pathological data was collected at post-mortem. Analysis of variance and Tukey Honest Significant Difference, a post hoc test, multiple comparisons of means were performed. The results showed that immune response to Mycoplasma vaccine antigens in helminth infected group (A) was significantly lower than that in vaccinated none helminth infected (B) group (p<0.05).Evidence from this study indicates that worm infection impacts negatively on immune response to vaccine antigens. Thus, we recommend that deworming exercise should be carried out before planned vaccinations are carried out.