Anthrax threat still a reality in Saskatchewan

Source: Saskatchewan Agriculture and Food

With four new cases reported so far this year, Saskatchewan producers are not out of the woods yet when it comes to the threat of anthrax.

The reports came from two regions of the province. Three cases were found in the northeast/east-central grain belt, and the fourth was located in the southwest corner of the province in the Shaunavon area.

The recorded cases began in February and continued into mid-March. They were associated with feed that was contaminated by soil containing anthrax spores.

“This process was slightly different than the norm with regard to how the animals most frequently become affected,” said Dr. Sandra Stephens, a Veterinary Program Specialist with the Canadian Food Inspection Agency (CFIA).

“It’s still important that producers vaccinate their livestock to protect against anthrax contamination,” she stated. “Since the anthrax spore is resistant to any environmental breakdown, it will remain viable in the environment for decades. We are not certain exactly how many years these spores will survive in the environment; however, estimates show that the range of survival includes anywhere between 50 to 200 years.”

Producers are advised to talk to their local veterinarians in order to get the vaccine required to prevent contamination.

The cost of the vaccine will be set by the practitioner, usually anywhere from $2 to $2.25 per dose.

The appropriate time for producers to vaccinate their cattle is just prior to the animals being put onto pasture in the spring. The product insert indicates that immunity should last between six and 12 months. The range exists due to variations in individual animals.

“We assume there are a certain number of spores that an animal will be able to consume without causing death,” Stephens said. “There are various estimates pertaining to the exact number of spores needed to make an animal sick. It would take approximately 500 or 700 spores, up to a couple thousand.”

To put this estimate into perspective, it is important to note that one gram of soil can potentially contain enough anthrax spores to make several animals sick.

“People often have the vision that the spores are spread nice and evenly around the prairies. However, that isn’t the case. They are in clumps,” Stephens explained.

“Spores will be found where an animal had died in the past, or where a scavenger had dragged a piece of meat that it had ripped off a carcass, perhaps a hundred meters away. This will leave pockets of spores in the soil.”

In the summer, most situations will involve an animal picking up the anthrax from the soil itself.

Animals die very quickly, so it is unusual for producers to observe cattle that are sick before they expire. Symptoms caused by anthrax poisoning include very high temperatures, bloody discharge from the nose and/or mouth, as well as weakness. Stephens says that once the animal starts showing clinical signs, they will often be dead in about two to four hours.

Anthrax is a reportable disease in Canada. “Producers are required by law to report any suspicion of anthrax,” she noted. “When producers come across sudden mortalities on pastures, they should rule out what the causes may have been. It is to their benefit to take the proper steps to dispose of the carcass, since it will be their animals grazing in that pasture in the future.”

Stephens indicates that producers should either contact their local veterinarian or the nearest CFIA office in order to report a suspected case of anthrax.

For more information, contact:
Dr. Sandra Stephens, Veterinary Program Specialist
Canadian Food Inspection Agency
Phone: (306) 975-519