The study was conducted to determine the prevalence of nematode infection, establish reproductive indices and identify the existing correlations between infection and reproductive indices among dairy cattle in Cagayan Valley Fecal samples of dairy cattle (n=256) were subjected to flotation and Baerman larval culture method to identify nematode eggs and larvae. Despite all animals being dewormed, a high level of infection was observed in the samples collected with 112 samples (71.34%) showing infection with at least one type of nematode, 44 samples (28.03%) were infected with two types of nematodes, and 1 sample (0.63%) was found positive with three types of nematodes. The overall prevalence for Haemonchus sp. Trichostrongylus sp., and Trichuris sp. were 39.45%, 35 16%, and 5.08% respectively. Evaluation of reproductive indices showed that during first service (n=72), fertility (59.72%) and conception rates (95.35%) were within standards. However, calving to first service interval (CFSI) (n=116) was extended with 38.79% of cows taking more than 70 days to return to heat. Calving to conception interval (CCI) (n=116) was extended with 40.52% taking >110 days to get pregnant. Calving interval (CT) (n=146) was extended with 34.25% of cows having >500 days interval. Infection with Trichuris sp. was correlated with extended CFSI (-0.176, p = 0.029, CCI (r = 0.208, p = 0.01) and CI (-0.183, p - 0.023) while Haemonchus sp. infection was correlated with extended Cl (r = 0.246 p < 0.002) Improvement in health management is highly recommended to reduce or prevent nematode infection in dairy cattle.

Thesis (Doctor of Veterinary Medicine)

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