Dr. Haugland

Dr. Jen Haugland

With June seeing some much needed sunshine, producers across the region are gleefully opening gates and turning their livestock out to grass. It is a rewarding time for most farmers and ranchers with calving wrapped up and branding almost all done.

For many producers however, early summer is when rattlesnakes are starting to come out of their dens and it is a safe bet that wherever cattle go to graze, rattlesnakes will be there too.

The predominate species across Montana and western North Dakota is Crotalus viridis, more commonly known as the prairie rattlesnake. Although it is uncommon for any animal to die after being bitten by a prairie rattlesnake, the event can be very painful and traumatic to an animal and it is important to give them prompt and proper care.

Rattlesnakes in general have three different kinds of bites: an aggressive bite, where they let out the most venom, is used by a snake only when they think they can kill the prey and eat it. Mostly rodents and occasionally small dogs can fall victim to this bite; a defensive bite, in comparison, releases less venom and is used mostly on large dogs and livestock; and dry bites, meaning they contain no venom. 25 percent of all snake bites are categorized as dry bites. For obvious reasons a dry bite is less detrimental to the animal, but puncture wounds and slight swelling may still appear.

If you are out on a hike or in the hills moving cows and your dog is unfortunate enough to get bit by a rattlesnake, Dr. Jen Haugland, owner of North Country Vet Services, recommends calling your veterinarian immediately. Dogs are less likely to get a secondary infection from the bite, but supportive care is critical to ensuring there are no complications.

“Don’t let your dog walk or run back after they have been bit. It is best to keep them calm and carry them back. That will slow the venom from spreading through the blood stream,” Dr. Haugland advised.

She went on to note that Benadryl could come in very handy in this kind of a situation and it may be a good idea to carry some in your saddle bags or hiking backpack. Benadryl makes dogs sleepy, so they will be more likely to stay quite and calm before arriving at the vet for professional care. Dr. Haugland suggests you contact your personal veterinarian for dosing recommendations. 

When it comes to larger livestock animals, approaches to rattlesnake bites are different. For example, horses are most often bit on the nose while they are out grazing, and the biggest concern is their nostrils swell shut and impede their ability to breath. If you are lucky enough to see a horse get bit and can offer assistance before the swelling takes off, it is recommended to insert something into their nostrils to prevent their airways from shutting. A simple piece of garden hose or even the case for a 60-cc syringe cut open on both ends would do.

Horses can receive Banamine as a way to combat the pain and swelling associated with the bite. It is critical to understand, however, that Banamine can only be administered intravenously or orally to horses. Injecting the drug intramuscularly could lead to deadly complications.

“Horses need to be on antibiotics after a snakebite because they almost always develop a secondary infection,” said Dr. Haugland. Broad-spectrum injectable or IV antibiotics are most commonly used.

Cattle, arguably, are the most resilient to rattlesnake bites, but the venom can cause a cow to abort so it is important to keep track of cattle out on summer range and take immediate action if you suspect a snakebite.

Dexamethasone (Dex) is a drug often associated with the treatment of snake bites in cattle, but recent research has shown that Dex can actually slow down the healing process, so a non-steroidal medicine like Banamine is preferred to help with initial swelling. Cattle can also benefit from a broad-spectrum antibiotic as well.

Both horses and cattle should be up to date on all their vaccines, especially tetanus, following a rattlesnake bite.

Rattlesnake venom is mostly made up of proteins that have the potential to cause long-term problems for the vital organs in an animal. The protein in the venom causes the organs to “leak,” so to speak, and the animal can become hypovolemic because of the lack of circulating blood. Often, vets recommend that animals be put onto IV fluids in an effort to keep the heart working properly.

Anti-venom is always an option and any vet can obtain vials as necessary. However, anti-venom is expensive, ranging anywhere from $200-500 a vial. Small animals may only require one vial after they are bitten, but large livestock may require up to four of five vials, depending on the location and severity of the bite. The use of anti-venom is really a financial decision and it is important to communicate openly with your veterinarian regarding care should the need arise.

Dr. Haugland points out that rattlesnakes are not the only threat to cattle out on range this time of year. Plant toxicity is also present in the early summer months with lupine and larkspur dotting the rangelands. Additionally, it has been noted in eastern Montana and the Dakotas that this year is prime for anthrax. Producers in those areas are advised to be on the look-out and contact their local and state veterinarians should they suspect their cattle have died from anthrax.