COLIC
We have had several colics to treat lately and after talking to those clients and answering questions about their horses it seemed proper to share some of that with you all.
Interestingly, multiple studies have found that cold weather or inclement conditions do not increase the incidence of colic as much as changes in management and husbandry practices do. Horses like consistency and if we alter the way we care for them, or the schedule and timing, that more likely impacts the incidence of colic than the weather itself. For example, cold temperatures may not cause colic, but frozen water buckets may. Altering the feeding schedule to get chores done before the storm, or after the weather improves, may cause anxiety and related gi problems. Winter and the conditions that come with it do make taking care of our horses more challenging, but do your best to keep the schedule and management practices consistent.
Colic is a vague term for abdominal pain. True, some colic episodes are serious and life-threatening problems with bowel that is entrapped or twisted. Also true is that some colic episodes are minor cramps or gas moving through the system. Horses do not know the difference between dangerous colic episodes and simple gas pain. The severity of pain is not always a reliable indicator as some horses are more stoic than others. It is possible for simple gas pain to escalate and become a more serious problem and for that reason we like to help the horse sooner rather than later. Often just walking can help to relieve cramps or gas pain. Banamine (flunixin meglumine) is a pain reliever often used for colic and it can increase the effectiveness of hand walking. Keeping Banamine on hand is a good idea (it is also the first drug we would ask you to give if the horse had a fever or swollen eye). When the temperatures outside are more pleasant, a good 10 minute cold hosing and some hand grazing can also help to relieve the abdominal pain.
Alerting us early in the process helps us keep abreast of the situation and make plans to see you and the horse if needed. We are happy to have you try the Banamine and walking and cold hosing and keep us posted. Often a trailer ride can help a horse move some gas or ease the cramps. Bringing the horse to our clinic can add to the benefits of your treatment at home as well as additional therapies we may provide.
BOTULISM
Last year there were many questions about using Botulism vaccine. We have discussed it here and with colleagues and have decided to recommend its use to our clients. We vaccinated all of our own horses last Fall and the process was smooth without any complications.
The disease is not new. It is caused by botulism toxin, produced by a bacteria, Clostridium botulinum. The resultant disease is in the form of paralysis. This toxin is a neuroparalytic unlike its “cousin” tetanus (Clostridium tetani) which is a neurostimulant. This disease is just as deadly as tetanus and horses are exquisitely susceptible. Like with tetanus, botulism is ubiquitous in the environment and all horses are at risk. It is not something we see commonly but recent weather changes and hay availability seem to be helping create an increase in the number of cases – causing us to rethink the value of vaccination.
Adult horses most often see botulism as forage poisoning. This results when the horse ingests preformed botulism toxin and then absorbs it through the intestine. Typically this occurs due to decaying vegetable material with bacterial proliferation and toxin production, rather than from contamination by a dead animal. A carcass in hay can still serve as a disease source for your horse. Some animals have the toxin in their intestinal tracts and as they decay that toxin can contaminate the hay. As mentioned, horses are very susceptible to this toxin and hay that cattle ate safely could still poison and kill a horse. The most frequent culprit is ensilage, or plastic wrapped haylage bales, but any improperly cured hay, or hay containing a carcass, could pose a threat.
Foals are more commonly affected by a variant of the disease called toxicoinfectious botulism. The C. botulinum bacteria persist in soils for a very long time, as spores. Foals may ingest these spores and then toxin is produced in their digestive systems. Adult horses are more protected by a robust intestinal flora as well as more developed digestive enzymes and acids (think of human babies that should not be fed honey while adults can).
Horses affected by this toxin usually show signs within 24 hours. Early signs may be subtle, like difficulty swallowing, more saliva, and taking longer to eat. Dilated pupils may be noticed. As the disease progresses more obvious weakness is apparent. In this case, just weakness, not the clumsiness or ataxia we see with other neurologic diseases like EPM. Muscle tremors or fasciculations may be observed (affected foals are called “shaker foals”). Eventually the horse will go down and die from respiratory failure.
Treatment of this disease is often unrewarding. An antiserum exists but is expensive to use and difficult to acquire. Aggressive and intensive nursing and supportive care are needed – such as tube feeding and a sling to help the horse get up and down. The prognosis is poor and most of these cases do not recover.
Botulism, while difficult and unrewarding to treat, is very preventable. The vaccine has been used for many years in places where the disease was thought to be more prevalent (most pregnant mares in KY are vaccinated to protect foals). With the rise in cases here and the increasing difficulty in ensuring a good supply of quality hay, we think it makes sense to protect your horses with this vaccine. The vaccine is given as a series of 3 doses, one month apart, the first year. Thereafter, a single annual booster will maintain immunity. Pregnant mares should be vaccinated in months 8, 9, 10 of gestation. Most adult horses could have this vaccine added as part of their Fall vaccines.
