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Working Ranch - November/December 2017

I BRENDA LEAL, USDA-ARS Quarantine Quandary Update on TEXAS CATTLE FEVER TICKS BY GILDA V. BRYANT n the late 1800s, Texas Cattle Fever caused extensive cattle losses. To combat this deadly disease caused by ticks, the Bureau of Animal Industries, predecessor of the USDA (see Looking Back, September/October 2017 issue, p. 162), developed the fi rst tick eradication program in 1906. When ticks were controlled across the southeastern U.S., the USDA and Texas Animal Texas Cattle Fever ticks attached to bovine host. These ticks gather in soft tissue along the dewlap, brisket, forearm, fl ank, udder and cod regions. Health Commission (TAHC) established a permanent quarantine zone along the Texas - Mexico border in 1943. Tick eradication was the preferred control method. Two ticks, Rhipicephalus annulatus and R. microplus, can carry microscopic parasites, Babesia Bovis or B. bigemina, which cause Texas Cattle Fever. Sonja Swiger, Ph.D., Veterinary/ Medical Extension Entomologist for Texas AgriLife A&M Extension, says the parasites enter the animal’s blood stream when parasite-infected ticks drink a blood meal. The parasites attack red blood cells, causing the animal to develop anemia, high fever and enlargement of the liver and spleen. It is fatal to some 90 percent of susceptible cattle. Although the protozoan is not in the U.S., they are active in Mexico and other countries. SPECIA L Animal Health REPORT 90 I WORKING RANCH I NOVEMBER / DECEMBER 2017


Working Ranch - November/December 2017
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