Ivermectin as an antiparasitic agent in cattle

Area of Science:

• Veterinary Parasitology
• Animal Health
• Pharmacology

Background:

• Gastrointestinal (GI) and pulmonary nematodes, along with ectoparasites, pose significant health and economic challenges in cattle farming.
• Effective parasite control is crucial for maintaining herd health and productivity.

Purpose of the Study:

• To evaluate the efficacy and safety of ivermectin in cattle against various internal and external parasites.
• To assess the drug's impact on different parasite life stages and host-parasite interactions.

Main Methods:

• Experimental trials were conducted on cattle administering ivermectin subcutaneously at a dosage of 200 micrograms/kg.
• Efficacy was assessed against adult and immature nematodes (GI and pulmonary), including inhibited larvae.
• Ectoparasite efficacy was tested against sucking lice, mange mites (Psoroptic and Sarcoptic), and cattle grubs.
• Safety was evaluated in bulls and pregnant cows, with adverse events monitored.

Main Results:

• Ivermectin achieved 95% or greater efficacy against adult and immature GI and pulmonary nematodes, including inhibited Ostertagia ostertagi larvae.
• Nearly 100% efficacy was observed against sucking lice, Psoroptic mange mites, Sarcoptic mange mites, and cattle grubs.
• No adverse effects were noted in safety trials at the recommended dosage, even in bulls and pregnant cows.
• A small number of cattle with grubs experienced fatal acute esophagitis due to a host-parasite reaction post-injection.

Conclusions:

• Subcutaneous ivermectin at 200 micrograms/kg is highly effective for treating nematode infections and ectoparasites in cattle.
• The drug is generally safe for cattle, including bulls and pregnant cows, at the recommended dosage.
• Careful monitoring is advised for grub-infested cattle due to potential host-parasite reactions.