Arizona adds fourth layer of cattle inspections as officials prepare new screwworm defense facility

Arizona cattle imported from Mexico will face four inspections before moving through the U.S. livestock system, as officials work to keep New World screwworm out of the state.

Three checks happen in Mexico. Veterinarians examine the animals, review documents, provide antiparasitic treatment and look for wounds or signs of screwworm larvae. The cattle also receive treatment intended to eliminate ticks and other parasites before crossing the border.

After the cattle enter Arizona, state livestock inspectors verify paperwork, record electronic identification tags and make sure a USDA accredited veterinarian completes transportation documents. Arizona has not detected New World screwworm, officials said. More than 1,200 fly trap samples have been submitted for testing, and reports of maggots have so far involved other species.

The state is also preparing a sterile fly distribution facility near Douglas, expected to operate from Bisbee Douglas International Airport. The hub would receive sterile flies produced in Edinburg, Texas, and support releases in Arizona, California and New Mexico. Officials are urging ranchers, livestock producers and pet owners to watch animals for wounds or unusual maggot infestations and report concerns promptly.