– Shane Hernandez, Graduate Student in Animal and Diary Science, UGA and Lawton Stewart, Extension Beef Cattle Specialist, UGA
Internal parasites, or worms, are a common problem impacting cattle that graze on pastures. When infected, animals may display visible symptoms such as: emaciation, diarrhea, and rough hair coat. However, sub-clinical issues may also occur which may impact animal performance such as a decrease in milk yield, weight gain, carcass characteristics, and fertility. These sub-clinical issues can cause significant economic impact to a production system because the effects are not always detectable to the “naked eye”. Often the negative impact is not recognized until the damage is done, and profit is lost.
Anthelmintic products are available to help control internal parasites. When the strategy of pour-on dewormers was introduced in the 1990s, the practice was widely adopted because of the ease of use. Producers could apply the product directly to the cattle’s back while it stood in a chute or alley. Over time, overuse and incorrect application have led to a potential resistance of internal parasites to these products. Other products, such as injectable dewormers and oral (white) dewormers, have not been used as extensively because of the increased time associated with these technologies.
A potential strategy to ensure larvae death of multiple parasite species is . . .