4 Major Allergies Found in Animals

List of four major allergies found in animals:- 1. Enzootic Nasal granuloma of Cattle 2. Milk Allergy 3. Anaphylaxis (Idiosyncrasy) 4. Allergic Dermatitis of Horses.

Allergy # 1. Enzootic Nasal Granuloma of Cattle:

Of the three known clinical types of chronic nasal obstructions in cattle, two have been identi­fied. One is caused by a fungus and another caused by a parasite — Schistosoma nasalis. The third type Enzootic nasal granuloma is caused by allergy.

Enzootic nasal granuloma have lesions, con­sisting of granulomatous nodules—1- 4 mm in diameter and height, in both nostril. The lesions extend from just inside the nostril posteriorly for 5 to 8 cm. They may be a few in number or packed closely. Their texture is firm but the mu­cosa appears normal.

A mucopurulent discharge occurs in many animals. The principal clinical symptom is dyspnoea caused by obstruction to the air passage. The disease may produce severe distress but the animals do not die. The severity of the signs may fluctuate but they progress slowly and then remain static.

Treatment:

Cortico-steroids may be used. If necessary, surgical operation may be resorted to.

Allergy # 2. Milk Allergy:

When the cows are being dried off, due to retention of milk, signs of allergy—principally urticaria—are often manifested by cows. This may recur during subsequent drying off periods in the same cow and this is some sort of hereditary syndrome.

There is urticaria, specially on the eyelids or may be distributed generally. Respiratory dis­tress, muscle tremor, coughing, kicking at the abdomen and bellowing may occur. Other cows may show dullness, recumbency, ataxia, inability to rise. Temperature and pulse are normal. Respi­ration rate may increase greatly.

Diagnosis:

It can be made by intradermal injection of an extract of cow’s own milk. The milk may be diluted in the ratio of 1 in 10,000 and a positive reaction occurs manifested by oedematous swelling within minutes of the injection.

Treatment:

Spontaneous recovery normally occurs. Antihistamines are effective if given early and should be repeated at 24-hour intervals. Corticosteroids may also be used. By avoiding milk retention in susceptible cows, it can be pre­vented.

Allergy # 3. Anaphylaxis (Idiosyncrasy):

It is the exaggerated reaction to a foreign protein which sometimes follow inoculation, stings etc. It is frequently encountered on giving a second dose of vaccine or of .serum in the process of immunizing and animal some disease or a warble is killed while still in a cow’s back. It is a reaction which occurs when an antigen is administered parenterally to an individual whose cells have been sensitized to this specific antigen.

Etiology:

Sensitization of the cells, the al­lergic state or condition, is accomplished by con­tact with a wide variety of antigens, such as bacteria and their products, pollen, sera, drugs, food, oils, resins and many others. Antigens may be absorbed by inhalation, ingestion, injection or from a focus of infection.

In the process of sensi­tization by contact, antibodies are formed in the cells, and, thereafter, parenteral injection of the antigen results in an altered linkage of the cells to the antigen with an explosive reaction called anphylactic shock. Serum accidents are quite com­mon in animals.

In the selection of sera or aggres­sions or biological products containing sera, they should be derived whenever possible from ani­mals of the same species as those to be injected. In the use of anti-haemorrhagic septicaemia prod­ucts in cattle, those of equine origin should be avoided. Bacterins and vaccines are the frequent causes of anaphylactic shock.

Symptoms:

Following the injection of a haemorrhagic septicaemia bacterin, there may be dyspnoea and trembling. The onset may occur immediately or within an hour. Dyspnoea and pulmonary emphysema may persist for 24 hours. Oedematous swellings around the muzzle, the eyes and all over the body may be formed.

These are accompanied by intense itching, colic and extreme dyspnoea with rapid breathing. In severe attacks, there is open mouth breathing with symp­toms of oedema and emphysema of the lungs which may persist for 24 hours. There may be collapse immediately after the injection with re­covery or death within a few minutes. Other symptoms are lacrimation, coughing, pulmonary haemorrhage with bloody froth at the nostrils.

Treatment:

Adrenalin (1:1000) solution in doses of 3 to 8 ml. administered subcutaneously is a specific for serum accidents. It should be kept ready at hand whenever bacterins or sera are used. Injection may be repeated after a few min­utes if necessary. To avoid anaphylactic shock, the best method is to inject a little quantity of the serum subcutaneously to determine sensitiveness prior to injection of the prophylactic or therapeu­tic dose.

Allergy # 4. Allergic Dermatitis of Horses:

This is an intensely itchy dermatitis of horses caused by hypersensitivity to insect bites. Hyper­sensitivity to the bites of Sandfly — Culicoides brevitarsus. Other allergens are Stomoxys calcitrous and Culicoides pulicaris.

Most cases occur during hot humid months of summer and disappear during winter months. Horses of all ages are affected.

Symptoms:

Lesions are usually confined to the butt of the tail, crest poll, rump, withers, along the back and ears. In severe cases, the lesions may extend to the body, neck, face and legs. There is intense itching—specially at night— and the horse may scratch against any fixed object for hours. Constant scratching may cause severe inflammatory lesions and loss of hair.

Diagnosis:

Intense scratching, the dorsal distribution of the dermatitis and seasonal occur­rence are quite diagnostic. Eosinophil and platelet count are elevated.

Treatment:

Local and parenteral applica­tion of antihistamine drugs may give temporary relief. Long—acting corticosteroids can give relief for one month.