Seroprevalence and Clinical Outcomes of Neospora caninum, Toxoplasma gondii and Besnoitia besnoiti Infections in Water Buffaloes (Bubalus bubalis)

SIMPLE SUMMARY: Over the recent years, increasing demand for buffalo products and consequently expanding its productivity has generated concerns regarding diseases that reduce fertility or cause abortion but the attention has been focused mostly on infectious diseases. Thus, exploration on the capacity of parasitic pathogens in relation to reproductive losses in this species are needed. This was the first study investigating, simultaneously, the role and changes induced by Neospora caninum, Toxoplasma gondii and Besnoitia besnoiti in water buffaloes in southern Italy. The outcome of this study revealed a high exposure of water buffaloes to both N. caninum and T. gondii, whereas all the animals resulted negative to B. besnoiti. The mono-infection with N. caninum seems mainly associated with abortion and presence of retained foetal membranes, while mono-infection with T. gondii has been associated with an increase of days open. In case of co-infections with both pathogens, the effects on the animals are related to abortion and embryonic death. The outcome of this study may be considered the starting point to promote the awareness about parasitic infections in buffalo medicine. ABSTRACT: One hundred twenty-four water buffaloes (Bubalus bubalis) originating from 9 farms located in southern Italy were tested to investigate simultaneously, for the first time, the seroprevalence of the protozoa Neospora caninum, Toxoplasma gondii and Besnoitia besnoiti by ELISA tests and to evaluate the clinical findings potentially associated to the presence of these aborting parasitic pathogens. Twenty-five of 124 buffaloes (20.2%) were positive for N. caninum, while 17/124 (13.7%) for T. gondii. No buffalo showed specific antibodies for B. besnoiti. Nineteen of 124 animals (15.3%) were found seropositive for both T. gondii and N. caninum. The univariate statistical analysis showed that the seroprevalence of N. caninum is significantly associated with abortion and presence of retained foetal membranes, while the seroprevalence of T. gondii is significantly associated with an increase of days open. The logistic regression models showed that the co-infection by N. caninum and T. gondii strengthened the abortive effects (OR = 7.330) and showed further negative effects on the parameter embryonic death (OR = 2.607). The outcome revealed herein represents a high exposure of N. caninum and T. gondii in water buffaloes with reproduction disorders that deserves attention for both economic reasons, animal health and welfare.