Avitellinosis

It is a disease caused by cestodes (tapeworms) of the genus Avitellina centripunctata mainly parasitising the small intestine.

Avitellinosis affects goats, sheep, less commonly cattle, and other wild ruminants (saiga, argali, camel, etc.)

Since avitellinosis affects the small intestine, the helminth eggs are released into the environment, where they are eaten by the intermediate host, the insect legworms (collembolae). In the body of the collembola, the larvae grow into an invasive cysticercoid and are subsequently eaten in the pasture by the animal together with the infected collembola. This is how the infection occurs.
This disease is widespread in Central Asia, Kazakhstan, Moldova, and southern Ukraine. In the Russian Federation, it is widespread in the Chita region, Buryatia, Dagestan, Krasnodar and Stavropol Krai, Rostov and Arkhangelsk regions.

Among sheep in Central Asia and Transcaucasia the peak of the disease is observed in autumn and winter. In some cases, it can occur in spring.

Collembolae are common where vegetation and moisture rich pastures are available.

Clinical picture of avitellinosis

The clinical picture is as follows:

decreased mobility and appetite (the animal stands with its head down);

moaning;

frequent breathing;

diarrhoea (diarrhoea);

restlessness;

convulsions;

paralyses;

impaired co-ordination of movement.

Death occurs in 1-2 hours. Less often in 5-6 hours after the appearance of the first signs.

Diagnosis of avitellinosis

 In vivo diagnosis: helminthoscopy is the most effective means of diagnosis in avitellinosis.

Sexually mature avitellins are excreted in the faeces. They are firmly fixed in the faeces and cannot be washed out. Under the microscope, 1-10 segments the size of a poppy seed can be detected, which are milky white in colour.

Postmortem diagnosis: pathological and anatomical changes characteristic of the disease are taken into account, as well as the presence of the avitellins themselves in the small intestine in the form of a white cord.

Avitellinosis should be distinguished (differentiated) from some infectious diseases, especially from bradzot-like diseases (infectious diseases affecting ruminants' pre-gastric glands) with a similar picture. 

Treatment and prophylaxis

Treatment and prophylaxis is giving preparations on mebendazole, niclosamide, praziquantel, fenbendazole.

Three prophylactic deworming treatments are given to prevent dispersal of avitellin. Young sheep of the current year of birth are dewormed for the first time at the end of May, the second in September, and the third in December. It is sufficient to treat adult sheep twice a year - in spring (April-May) and autumn (November-December). In Kazakhstan, Central Asia and Transcaucasia, spring deworming should be carried out in April.