Seroprevalence of Foot and Mouth Disease Virus Infection in some Wildlife and Cattle in Bauchi State, Nigeria

Abstract

BackgroundFoot and mouth disease (FMD) is one of the most economically important transboundary animal diseases with devastating consequence on livestock production and wildlife conservation. The objectives of the study were: to determine the seroprevalence of FMDV in wildlife and cattle and identify circulating FMDV serotypes in wildlife and identify potential risk factors that will contribute to transmission of the disease at the wildlife-livestock interface in Yankari Game Reserve and Sumu Wildlife Park in Bauchi State, Nigeria.\n\nMethodsBlood samples were collected between 2013 to 2015 from some wildlife and cattle respectively within and around Yankari Game Reserve (YGR) and Sumu Wildlife Park (SWP) in Bauchi State, Nigeria. The Wild animals were immobilized for blood collection using a combination of Etorphine Hydrochloride (M99(R) Kruger-Med South Africa) at 0.5-2 mg/kg and Azaperone (Stresnil(R), Janssen Pharmaceuticals (Pty.) Ltd., South Africa) at 0.1 mg/kg using a Dan-Inject(R) rifle (Dan-Inject APS, Sellerup Skovvej, Denmark) fitted with 3 ml dart syringe and for reversal, Naltrexone (Trexonil(R) Kruger-Med South Africa) at 1.5 mg IM was used, cattle were restrained by the owners for blood collection. Harvested Sera from blood were screened for presence of Antibodies against FMDV using prioCHECK(R) 3 ABC NSP ELISA kit and positive samples from wildlife were serotyped using Solid-Phase Competitive ELISA, (IZSLER Brescia-Italy). Data obtained were analysed using Graphpad Prism version 7.\n\nResultsThe results showed that 197 (65.7%) of the 300 serum samples from cattle and 13 (24.5%) of the 53 serum samples from wildlife tested positive for antibodies to the highly conserved non-structural 3-ABC protein of FMDV and statistically significant (P <0.05). Classification of cattle into breed and sex showed that detectable antibodies to FMDV were higher (P <0.05) in White Fulani 157 (72.8%) than red Bororo 23 (39.7%) and Sokoto Gudali 17 (33.3%) breeds of cattle whereas in females detectable FMDV antibodies were higher (P <0.05) 150 (72.8%) than in males 47 (50.0%). In the wildlife species, antibodies to FMDV were detected in waterbuck 2 (28.6%), elephant 1 (25.0%), wildebeest 4 (33.3%) and eland 6 (25.0%). Four serotypes of FMDV: O, A, SAT-1 and SAT-2 were detected from the 3-ABC positive reactors in waterbuck, elephant, wildebeest and eland. Contact of wildlife and cattle during utilization of the rich resources in the conservation areas is a potential risk factor for the spread of FMDV in the study area.\n\nConclusionsPresence of FMDV antibodies in cattle and some wildlife were observed and serotypes of FMDV: O, A, SAT-1 and SAT-2 were detected from the 3-ABC positive reactors in some of the wildlife. The study highlights the need for active surveillance of FMDV in wildlife and pastoral cattle within and around wildlife conservation areas in Nigeria. FMD surveillance system, control and prevention program that targets wildlife and livestock at the wildlife-livestock interface level will be beneficial to the livestock industry and wildlife conservation goals in Bauchi State, Nigeria.\n\nAuthor summaryFoot and mouth disease (FMD) is an important trans-boundary viral disease of both domestic and wild cloven hoofed animals characterized by high morbidity with devastating consequence on the livestock worldwide. Despite the endemic nature of FMD in Nigeria, little is known about the epidemiology of the disease at the wildlife-livestock interface level. To address this gap, blood samples were collected between 2013 to 2015 from some wildlife and cattle respectively within and around Yankari Game Reserve (YGR) and Sumu Wildlife Park (SWP) in Bauchi State, Nigeria. Wild animals were immobilized using a combination of Etorphine Hydrochloride (M99(R) Kruger-Med South Africa) at 0.5-2 mg/kg and Azaperone (Stresnil(R), Janssen Pharmaceuticals (Pty.) Ltd., South Africa) at 0.1 mg/kg using a Dan-Inject(R) rifle (Dan-Inject APS, Sellerup Skovvej, Denmark) fitted with 3 ml dart syringe and for reversal, Naltrexone (Trexonil(R) Kruger-Med South Africa) at 1.5 mg IM was used, cattle were restrained by the owners for blood collection. Harvested Sera from blood were screened for presence of Antibodies against FMDV using prioCHECK(R) 3 ABC NSP ELISA kit and positive samples were serotyped using Solid-Phase Competitive ELISA, (IZSLER Brescia-Italy). Out of the 300 and 53 sera collected from cattle and wildlife 197 (65.7%) and 13 (24.5%) (P <0.05) respectively tested positive for antibodies to the highly conserved non-structural 3-ABC protein of FMDV by the FMDV-NS blocking ELISA. Classification of cattle into breed and sex showed that detectable antibodies to FMDV were higher (P <0.05) in White Fulani 157 (72.8%) than red Bororo 23 (39.7%) and Sokoto Gudali 17 (33.3%) breeds of cattle whereas in females detectable FMDV antibodies were higher (P <0.05) 150 (72.8%) than in males 47 (50.0%). In the wildlife species, antibodies to FMDV were detected in waterbuck 2 (28.6%), elephant 1 (25.0%), wildebeest 4 (33.3%) and eland 6 (25.0%). Four serotypes of FMDV: O, A, SAT-1 and SAT-2 were detected from the 3-ABC positive reactors in waterbuck, elephant, wildebeest and elands. The results showed presence of antibodies to FMDV in some wildlife and cattle and suggest that wildlife could equally play an important role in the overall epidemiology of FMD in Nigeria. FMD surveillance system, control and prevention program should be intensified in the study area.