Temporal Pattern of Suspected Cerebrospinal Nematodiasis in Goats in Kandy District: A Retrospective Study Using Case Records of the Farm Animal Veterinary Teaching Hospital

Cerebrospinal nematodiasis (CSN) is a neuropathological disease in goats caused by migration of third-stage larvae of Setaria spp., which is transmitted by mosquitoes. It often leads to lifelong neurological complications, productivity losses, and culling recommendations. Understanding its regional epidemiology is essential for developing effective prevention and control strategies. This retrospective descriptive study analysed the temporal patterns of CSN occurrence in the Kandy district using clinical records from 4,524 goats presented to the Farm Animal Veterinary Teaching Hospital, University of Peradeniya, from 2016 to 2023. The overall prevalence of suspected CSN cases was low (5.0%) among study goats. However, a distinct temporal variation in CSN prevalence was observed, with peak disease occurrence between February and April, reaching its highest in March (13.6±6.4%). This period coincided with the region’s convectional rainfall episodes, suggesting that optimal rainfall conditions may have contributed to increased CSN occurrence. A decline in CSN prevalence was observed from May to September, corresponding with reduced rainfall. Additionally, a substantial drop in cases from April to May and again from September to November aligned with periods of higherthan- average rainfall, which may have disrupted mosquito breeding. These findings suggest that rainfall patterns significantly influence the temporal distribution of CSN, likely by affecting mosquito populations, the intermediate hosts of Setaria digitata. The findings emphasise the need for targeted disease prevention strategies, such as implementing strategic deworming protocols before the peak disease period and enhancing farmer awareness of mosquito control measures to mitigate CSN risks in the study region.