The Welfare Implications of Grass Sickness

by Dr D. L. Doxey

Grass Sickness (Equine dysautonomia) for all practical purposes falls into two categories. Firstly, there is the acute, subacute and a proportion of the chronic group which eventually die. Secondly, there are those chronic cases which prove to be treatable and eventually recover. The way in which these cases are viewed is different.

In the first group which usually accounts for about 75-80 % of grass sickness cases, the two most important criteria are establishing that the diagnosis is correct and then alleviating the animal’s suffering as soon as possible. There is no doubt that these animals do suffer and in the acute cases particularly, watching them suffer is extremely stressful to the owner or regular groom. Such cases will exhibit severe abdominal pain, will be unable to swallow and as a result become dehydrated. In addition many also sweat, tremble and become severely depressed. Your veterinary surgeon will only be able to make a diagnosis after careful clinical and rectal examinations and even then in some cases a definite diagnosis is impossible because intestinal twists can produce similar clinical signs. In cases of doubt, abdominal surgery is indicated but this requires specialised facilities and is very expensive. If surgical facilities are not available, these extremely distressed animals should be put to sleep as soon as possible. To keep them alive in such circumstances is cruel.

The subacute and bad chronic cases also present a diagnostic challenge which even experienced veterinary surgeons will find difficult. Because an instant diagnosis may be impossible, sufficient time has to be given to assess the case fully and during that period the patient will have to be given pain killing drugs, fluid therapy if dehydration develops and nutritional and nursing care. The animal’s welfare will be compromised if any of the relevant steps are omitted during the time it takes to reach a diagnostic conclusion. The care and contact given by the groom or owner is important and many cases appear to feel better when someone is close to them. However this does make taking the final decision, once the diagnosis has been established, very difficult. Owners see the animal’s demeanour fluctuating from depression to alertness and back again in a period of hours and cannot help hoping that everything will turn out well at the end of the day. Long experience has taught clinicians at the R(D)SVS that once the diagnosis has been made and it has been established that the animal’s inability to swallow, depressed attitude to life, or poor physical condition mitigate against treatment, euthanasia is the best course of action. This is not a step to be taken lightly, but to prolong life in such circumstances is not in the best interests of the animal’s welfare, and may well have a serious, adverse effect on the owner or groom’s welfare.

The situation in cases which are selected for treatment after a careful clinical workup is somewhat different. In this case the animal will be in some distress, will have problems in smelling and swallowing food and will probably have repeated mild colic. In these cases low doses of pain killing drugs are given when required, in addition to the specific therapy required to get the intestinal tract working again. The main welfare aspects in these cases are concerned with keeping the animal inside and warm. Temperature control is a problem in grass sickness horses and the animal has to be kept rugged up to prevent the body temperature falling in cool or cold weather. To add to the difficulties, most cases sweat and their coats soon become matted if not regularly washed and groomed. The patients appreciate this treatment and also appear to relish human contact. There is no doubt that a good groom who is prepared to spend time talking to the patient, trying to judge what food is required on an hour to hour basis, and actively stimulating the animal when depression is a problem, is more beneficial to the patients welfare than all the drugs in a veterinary armoury.

Grass sickness welfare is not a simple concept but in all types of cases the comfort of the patient and the prevention of prolonged unnecessary suffering are the goals to be aimed for.