Intensification of livestock industries require conducting procedures to improve fodder base, labor organization, and planning scientific-based treatment and preventive measures. Despite wide antiparasitic action in the Republic of Belarus parasitic diseases still remain an important issue. Animals affected with helminthes  during examination seem relatively healthy, and the only special parasitic research methods allow to reveal their infection. One of the first places in their dissemination strongylatosis take the gastrointestinal tract of cattle. Animals affectino by parasites of the group reaches 100%. From the generic composition identified one of the greatest economic damage causing strongylatosis gastrointestinal tract of cattle is oesophagostomosis, it’s distribution according to our research reaches 23 % or more. Oesophagostomosis – a parasitic diseases caused by nematodes of the genus Oesophagostomum Molin, 1861 Sem. Trichonematidae, characterized by lesions of the small and large intestine, and dysfunction of the gastrointestinal tract. Measures against parasitic diseases of animals should be complex, taking into account the technology of animal keeping, biology of the pathogen, availability of effective drugs. Taking into account the urgency and importance of the problem of combating with helminthes in cattle, we have been set the problem to determine the efficiency  and safety of a new drug of plant origin „Oregopharmum” at esophagostomosis  of cattle. 1.0 g of the drug contains 100,0 mg of oregano oil (Origanum Aetheroleum) and filler (kaolin). Oregano oil  is obtained from a plant of oregano (Origanum vulgare), which is a combination of phenols comprising more than 30 different components in different percentages, the main components are carvacrol (55–85 %) and thymol (0,5–10 %). Essential oils that are part of oregano oil have anthelmintic action affecting the central and vegetative nervous system of the parasite. To conduct the research two groups of young cattle were formed. One group of animals (infested esophagostomy) was given oregopharmum individually inside during morning feeding at a dose of 400 mg / kg of live weight with the intervals of 24 hours. The control animals were not given the drug. The material for the study were samples of feces and blood.

The results of the study after application of oregofarmum at a dose of 400 mg / kg for three days show that on the 15^th day of the study of eggs in the feces of calves oesophagostoma were not found. To study the effect of the drug on the body of cattle we studied the blood. The results allow to judge about the changes in the organs and tissues of animals that do not manifest clinically. It was found that as a result of the drug application restoration of hematological parameters of blood is taking place: increases the number of red blood cells and hemoglobin level; reduces the number of leukocytes. In the serum a total protein concentration increases, decreases the activity of hepatic enzymes. The results showed that the drug „Oregofarmum” was highly effective (100 %) at oesophagostomosis of cattle and was minimum toxic.

Key words: ezofagostomoz, invasion, extent of infestation, the intensity of infestation, cattle, drug Oregofarm, feces, blood.