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In recent developments, Canada has taken significant action to suspend several animal exports from Texas due to concerns surrounding the New World screwworm, a pest known for its devastating effects on livestock. This decision, communicated by the U.S. Department of Agriculture (USDA), underscores the urgency of the situation.
The Canadian Food Inspection Agency (CFIA) has announced an immediate halt on the export of various animals, including horses, pigs, cattle, bison, sheep, goats, deer, elk, moose, and llamas, among others. While imports from other states remain permissible, they must not have resided in or passed through Texas within the 21 days prior to their arrival in Canada.
According to the USDA’s recent news release, accredited veterinarians are required to provide information regarding the animals’ residency or transit through affected states. Failure to comply could result in shipments being denied entry into Canada, highlighting the stringent measures now in place to protect animal health.
The CFIA has stated its commitment to ongoing collaboration with U.S. authorities to monitor the situation and adjust regulations as necessary. “While our colder climate is not hospitable for the long-term establishment of the fly in Canada, they can survive shorter periods of time in the summer months,” the agency noted, emphasizing the importance of preemptive measures.
This decision follows a confirmed infestation of New World screwworm in South Texas, first reported in June, which raised alarms among the Texas cattle industry. As of July 10, there were 34 confirmed cases of the pest infiltrating livestock across the state.
Investigations by the Texas Animal Health Commission have identified potential sources of the infestation, linking it to small wildlife and rodents such as armadillos, opossums, and rabbits. USDA Secretary Brooke Rollins has also suggested that recent border policies and illicit cattle movements by drug cartels may have contributed to the situation.
Despite the ongoing investigations, the initial source of the New World screwworm’s presence in Texas remains uncertain. The Texas Parks and Wildlife Department continues to explore the paths through which this invasive pest breached the Texas-Mexico border.
To combat this pest, the USDA has restricted all southern ports of entry to livestock imports from Mexico since May 2025, effectively halting legal cattle crossings from Mexico. Experts estimate that the eradication of the New World screwworm will require the release of 500 million sterile flies weekly, yet current U.S. production stands at about 100 million per week, with plans for expansion still in progress.
As the situation develops, Texas officials and federal authorities are faced with the challenge of finding effective strategies to mitigate this emerging threat to livestock health and the state’s agricultural economy.
