Migration season represents a cause for concern among poultry farmers, said Dr. Craig Coufal, Texas A&M AgriLife Extension Service poultry specialist in College Station, Texas. Coufal said the threat of avian influenza is heightened due to annual migrations by wild bird species, particularly waterfowl.
“It’s that time of year,” he said. “You’ve got large numbers of ducks and geese that have been commingling and interacting in the North, and there is real concern about those migratory birds coming into contact with domestic birds via vectors such as humans, droppings, an airborne contaminant or direct contact. People need to be vigilant about keeping migratory birds away from their domestic birds.”
Coufal said avian influenza is usually not deadly to wild birds, and the strains found in the U.S. in past years have not been shown to infect people but can cause major problems for poultry producers because there is no treatment for the virus. Highly pathogenic avian influenza causes severe illness and high mortality rates in domesticated birds, while low-pathogenic avian influenza causes only minor illness and low mortality rates.
In 2015, around 50 million birds -- mostly turkeys and laying hens -- were lost due to an outbreak in the Midwest. To prevent the spread of the virus once detected, Texas protocols require all infected flocks be reported and quarantined. Infected birds are euthanized, and their carcasses are destroyed under most circumstances.
“Once domestic birds test positive for avian influenza, the federal government gets involved, and the only way to deal with an outbreak is to eradicate the host birds,” he said. “The only way to approach it is prevention. That means tightening up our biosecurity measures.”
The initial cause of the 2015 outbreak remains unknown, Coufal said, but scientists know human hygiene contributed to spreading the disease among some operations.
“One plausible scenario is someone going duck or goose hunting and then not properly sanitizing themselves before they enter their farm,” he said. “If you’re around wild birds, you need to properly sanitize everything, including bathing and changing clothes.”
Coufal said producers should remain vigilant throughout the migration, which typically ends in April when the birds return north. The disease is also more of a challenge in winter months because the virus’s survivability increases in cooler temperatures compared to summertime heat, he said.
Coufal said some tips for biosecurity include:
* Securing poultry houses against wild birds, pets and livestock.
* Restricting visitors from houses and coops, especially without thorough disinfecting.
* Dedicating specific shoes or rubber boots for exclusive use in poultry houses.
* Washing and disinfecting any shared equipment such as scales, feeders and drinkers.
* Initiating rodent and insect control programs.
“It’s time to be concerned but vigilant,” Coufal said. “The only thing that can be done is practice the utmost level of biosecurity and hygiene.”