against illegal movements or stray animals. 

 The buffer area under Federal and State quar- 

 antine extends 500 miles from Del Rio to the 

 Gulf of Mexico. This zone is patrolled con- 

 stantly by Department inspectors in coopera- 

 tion with Texas livestock sanitary authorities. 

 The area under quarantine includes parts of 

 Cameron, Hidalgo. Kinney, Maverick, Starr, 

 Val Verde, Webb, and Zapata Counties. 



The cattle fever tick was eradicated from 

 California many years ago. However, this 

 State also has a common border with infested 

 areas in Mexico, and animals illegally entering 

 the United States reintroduce ticks from time 

 to time. 



In October 1941, fever tick infestation was 

 discovered adjacent to the Mexican border in 

 the Tijuana Valley of San Diego County and 

 on a few farms in Los Angeles County to which 

 cattle had been moved from San Diego County. 

 Infested areas were quarantined and cattle 

 were systematically inspected and dipped. In- 

 festations in small areas in San Diego County 

 were also reported in 1948, 1944, 1949. and 

 1950. In each in.stance the ticks were eradi- 

 cated by following customary procedures. 



The most recent infestation in San Diego 

 County was in Marron Valley in June 1956. A 

 State hold-order was placed on the affected 

 area, and an inspection and dipping program 

 inaugurated. No additional ticks were found 

 after official dippings were started, and the 

 hold-order was lifted in June 1957. A double 

 fence was constructed across the valley. Plans 

 were made to chute-inspect cattle and horses in 

 Marron Valley periodically at least four times 

 a year. 



In Puerto Rico a tick eradication program, in 

 operation for a number of years, is coming to 

 an end. Here the tropical variety of the fever 

 tick was prevalent, and it was necessary to 

 treat sheep and goats as well as equines and 

 cattle. 



Troublesome ticks in Florida 



Florida was the last State, aside from Texas, 

 to be freed of fever ticks. The Federal quaran- 

 tine in Collier and Hendry Counties in the Big 

 Cypress Swamp area was lifted in December 

 1943. 



Deer, which served as hosts for the tropical 



tick, delayed final eradication. It was only 

 after the Florida Legislature provided author- 

 ity to eliminate this host that the vector was 

 eradicated. 



In 1947, slight infestations were found in 

 Broward, Charlotte, Collier, Dade, Hendry, 

 Lee, and Palm Beach Counties. Systematic 

 eradication efforts continued during 1947 and 

 1948. 



In October 1948, a heavy infestation of ticks 

 was discovered in Volusia County. Invc-^tiga- 

 tion of this outbreak disclosed additional in- 

 festations in Alachua, Brevard, Flagler, Jack- 

 .son. Lake, Madison, Orange, Osceola, Putnam, 

 and St. Johns Counties in Florida and on one 

 premise in Brantley County, Ga. All these in- 

 festations were caused by movement of cattle 

 from Volusia County. 



Systematic inspection and dipping brought 

 the outbreak under control, and all remaining 

 Federal quarantines were removed in Decem- 

 ber 1950. No additional infestations were 

 found until 1957. 



On April 23, 1957, a State inspector found 

 cattle fever ticks at the Okeechobee Livestock 

 Market at Okeechobee, Fla. The ticks were 

 identified as Boophilus microplua. This was 

 the first outbreak of fever ticks in Okeechobee 

 County since the wintc of 1945, when quaran- 

 tines were placed on that county and on Glades, 

 Highlands, and parts of Osceola and Polk 

 Counties. 



Since the 1945 infestation in Florida, cattle 

 passing through all auctions in the State had 

 been examined for ticks by experienced inspec- 

 tors, and all cattle except those selling for 

 slaughter had been dipped. It was as a result 

 of this routine check that the ticks were found 

 on cattle from two Okeechobee ranches. 



Immediate steps were taken to treat infe.sted 

 and exposed herds and place a State quarantine 

 on the area likely to be affected. Action was 

 also taken to trace animal movements in and 

 out of the area during the previous 2 or 3 years, 

 to place the premises involved under State 

 quarantine, and to investigate the po.ssible 

 source of the ticks. In all, more than 100 

 ranches in 10 Florida counties were quaran- 

 tined. Counties involved were Broward, Dade, 

 Glades, Hendry, Martin, Highlands, Okeecho- 

 bee, Palm Beach, and St. Lucie. Premises un- 



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