Background: Intestinal nematode parasites of equines have emerged as a pressing and urgent challenge due to their significant impact on the health and performance of these animals worldwide; therefore, implementing a deworming regimen has become vital to keeping a horse's parasite load at an acceptable level. Thus, the current study aimed to estimate the prevalence of nematodes infection , associated risk factors and evaluate the chemotherapeutic efficacy of different anthelmintic drugs by enrolling 195 fecal matter samples of working equines using flotation concentration techniques. Equines treatment were divided into four groups; Group 1 standard treatment (Albendazole orally), Group 2 intervention treatment (Doramectin injection), Group 3 intervention treatment (combination of Albendazole and Doramectin), and Group 4 was left untreated as a positive control.
Results: The overall prevalence of intestinal nematode parasites in working equines was 70.25%. The recovered nematodes were Strongylus species, with 87.17% followed by Parascaris equorum 30.76%, and Oxyuris equi was 12.82%. Concerning treatment efficacy, the highest cure rate was among Group 3 (77.14%), followed by Group 2 (68.57%) and Group 1 (40%), but the difference between Groups 2 and 3 is statistically insignificant. Interestingly, the effect of Doramectin injection is highly significant than other, especially for the reduction of Strongylus spp. and Parascaris equorum eggs according to Cohen's D test.
Conclusions: Translating such a potent combination of drugs into endemic areas will provide significant support for deworming and control programs against intestinal parasites of equines, especially those in the migratory phase, more than Albendazole alone, which has poor absorption as it requires a full stomach during administration.