Abstract

These days one of the real problems that cause the prejudice-economy in animal farms yearly is parasitic disease. For that reason and to prevent these problems the use of antiparasitic drugs is necessary. Ivermectin is a broad spectrum antiparasitic agent and is in different dosage forms such as injection, oral and pour-on. The aims of this study was to evaluate the efficacy of ivermectin pour-on administration against natural Nematodirus spathiger nematode infections in cattle and also to determine the prevalent rate of this parasite in Tabriz area. In this study, 120 heads of male and female hybrid cattle were used for LPG (larves per gram of feces) feces test. Willis method was applied for feces test and Stoll method was used for counting nematode larvae (LPG). After confirming worm contamination and counting N. spathiger nematode larves in feces in infected animals, ivermectin (0.5 mg/kg) pour-on was administrated. Feces test was repeated in 1, 7, 21 and 28 days after treatment. Results showed that total prevalence of N. spathigernematode infections was 33.33% in cattle of Tabriz area. The effects of ivermectin pour-on on N. spathiger nematode were 13.37, 44.96, 83.69 and 99.1% in 1, 7, 21 and 28 days respectively. In conclusion, because the effect of this drug against N. spathiger nematode was >99% (p<0.05), cattle can use this drug in anti-parasitic programme. Of course, the effect of this drug on other nematodes and parasitic infections need more investigation.

Key words: Ivermectin, pouron administration, Nematodirus spathiger, cattle.