BERLIN, Ohio — Plenty of good hay and water may see most horses through the winter months both healthy and happy, but as the spring temperatures start to rise, equine health becomes more of a concern as horse activity and exercise increase and foaling begins on many farms.

That’s why it’s important for horse owners to provide a spring check up for their horses in cooperation with their local veterinarian.

“For most riding horses, what I like to do is make sure we start with a general physical exam, checking the heart and lungs and making sure there is no swelling in the legs,” said Amity Wise, DVM at East Holmes Vet Clinic in Berlin, Ohio. “Spring is also a good time to check teeth, to make sure there are no sharp edges or a need to make any adjustments before using a bit in the riding season.”

Although dental problems do not just occur in the springtime, it is the time when most horses are going into their season of heavy usage. Correction of small problems, such as filing sharp points on the inside edge of the upper molars can mean the difference between a successful season or one of head throwing, bit chewing and fighting.

Some dental problems can prevent a horse from maintaining optimal body weight and condition.

Horses with malocclusions of incisors or broken off incisors may be unable to maintain body weight on pasture, often requiring supplemental feeding, such as additional hay or cubed feed.

Spring has long been considered an optimal time for annual vaccinations to ensure horses will have the highest possible immunity during the peak warm weather exposure period for many diseases.

“As horses travel more in the spring and summer and come into more contact with other horses, we like to make sure that they are vaccinated for flu, rhino (pnuemonitis), eastern and western encephalitis, and tetanus - and this area is pretty prevalent for West Nile virus” Wise said.

“Eastern and western encephalitis and West Nile virus are actually transmitted by mosquito, so we want to make sure they have a high level of immunity in the summer months, so spring is a good time for those vaccinations.

Longer, warmer days combined with green grass stimulate hormonal activity, making injuries from running into fences more common in the spring. Tetanus is always a concern whenever a full thickness laceration through the skin occurs.

Deworming should be done regularly and throughout the year, not just in the spring. But spring is an excellent time to deworm for stomach bots, since some bots mature in the stomach later than others and a wintertime deworming may not have killed them all.

“A lot of people only deworm twice a year, and that’s one thing that is kind of concerning,” Wise said. “We see a lot more parasites in those cases as they may only keep worms under control for about 30 days.”

Although Wise said debate continues among parasitologists as to the benefits and drawbacks of rotating wormers, she typically recommends a rotation schedule based on the barn’s particular situation, including how often they deworm, the number of horses in the area, risk of recontamination, etc., She recommends working with your local vet to set a schedule best suited to your barn’s individual needs.

The Ohio Quarter Horse Assoc. recommends using a combination of dewormers to provide the best defense against parasites as parasites become resistant to whole classes of drugs, not just name brands. As a result, they advise horse owners to develop a rotation schedule that rotates between the different chemical classes in order to maintain effective parasite control.

The two classes or deworming chemicals offering the broadest defense against parasites are macrocyclic lactones (including ivermectins such as Zimectrin, Rotectrin 1 and Equimectrin as well as moxidectribs such as Quest) and pyrimidines (including pyrantel pamoates, such as Strongid P and Rotectin 2 as well as pyrantel tartrates such as Strongid C and Strongid C 2X).

A third chemical class offering a more narrow range of parasite species control is benzimidazole, which has three subclasses: oxibendazol (Anthelcide EQ), oxifendazole (Equi-Cide and Benzel-min) and fenbendazole (Safe-Guard or Panacur). Resistance has been shown to occur in both benzimidazoles and primidines, which make these products less effective over time. Also, neither of these classes or dewormers includes boticide.

The most important thing to remember is to rotate chemical classes of wormers. For example, you cannot rotate Zimectrin with Rotectin 1, Equimectrin or Quest as they all come from the same chemical class. To use any of the above products, you’ll need to use an alternative wormer such as Strongid P, Rotectin 2, Strongid C, Anthecide EQ, Equi-Cide, Benzelmin, Safe-Guard or Panacur.

“Generally speaking, the ivermectins are probably the most efficacious at getting the worms and keeping the numbers down for around 60 days,” Wise said.

But again, that depends on the number of horses in the area and recontamination.

“There’s a lot of things that are still up in the air as far as dewormers.”

The three most common methods of deworming are paste, daily feeding or tube worming. Paste wormers are a convenient and cost effective way for horse owners to take control of their horse’s deworming program as long as they remember to rotate between at least two chemical classes of dewormers.

Wise said spring is also a good time to get a Coggins test done to test for Equine Infectious Anemia, which most horse owners must have if they plan to travel out of state with their horse this season. Because it may take one to three weeks to get back results for a Coggins test, it’s a good idea to have one in-hand well before you need it. The test is good for one year.

It’s important for horse owners to become educated and knowledgeable themselves on horse health issues to help maintain the health and condition of their equine companions, and also important that they work with their local veterinarians to develop a preventative health care program best-suited to their individual situation.

This farm news was published in the March 22, 2006 issue of Farm World.