[Residual action of Neguvon, Neocidol, Nuvanol and Dursban on the imaginal and larval stages of the housefly]. / Ostatuchno deistvie na neguvon, neotsidol, nuvanol i dursban vurkhu imaginanite i larvnite stadii na domashnata mukha.

It is shown that Dursban, Neocydol and Neguvon preparations, mixed with swine manure at amounts of 500 mg/kg, kill 100 per cent the larvae of the domestic fly up to the 30th, 20th and 10th day, respectively, while the Neguvon and Neocydol preparations in cattle manure, up to the 10th day. Lower concentrations possess a residual effect of a shorter duration. It is also shown that the type of the surfaces and the pH of the mater on which the preparations are placed markedly affect the inctesicide activity and the residual effect of the preparations. The highest activity and the longest residual effect manifest preparations that have been placed on surfaces with a low absorption capacity. The highest effect has been achieved when the preparations are smeared on glass, a lower one, when placed on wood, and the poorest, when laid on mortar.

[Trials in the therapy and prevention of sheep nose bots]. / Opiti za terapiia i profilaktika na ovtsete ot estroza.

Comparative experiments were carried out on the effectiveness of some antiparasitic agents for the treatment and prophylaxis of estrosis in sheep. An evaluation is made of all methods applied in the modern technologies of sheep raising. It was found that the method of fumigation of airtight premises using negouvon at the rate of 0.6 g/m3 and a 60-min exposure was adequate and effective for group treatment. Negouvon proved to be well tolerated by sheep and had no essential effect on the level of cholinesterase. The use of the preparation ranid is economically justified only with animals having a mixed infection of Fasciola hepatica and O. ovis larvae.

[Role of flies in the epizootiology of coccidiosis in poultry]. / Vurkhu roliata na mukhite v epizootologiiata na koktsidiozata po ptitsite.

The possibility is shown Musca domestica L. to ingest considerable amounts of oocysts of Eimeria tenella which remain in their digestive tract during 120 hrs. Both sporulated and non-sporulated oocysts remain viable and infectable. Non-sporulated oocysts do not form spores in the digestive tracts of flies, but after their excretion, they terminate normally their development under favourable conditions. It is shown that when flies, infected with oocysts, are fed to susceptible chicks, they are affected with coccidiosis.

[Role of the housefly in the epizootology of pseudoplague in birds]. / Znachenie na domashnata mukha v epizootologiiata na psevodochumata po ptitisite.

It has been demonstrated that Musca domestica L. could harbour the Newcastle disease virus. It has been isolated from the surface of the flies body 96 hours after these had been in contact with it, and from their digestive tract--after 240 hours. It has also been found that virus excretion in infected flies continues for 96 hours. It is believed that Musca domestica L. flies can participate in the spreading of the ND virus.

[Distribution, species composition and seasonal dynamics of ticks of the Ixodidate family in northwest Bulgaria]. / Razprostranenie, vidov sustav i sezonna dinamika na kurlezhite ot sem. Ixodidae v severozapadna Bulgariia.

It has been established that a total of 7 species of Ixodes ticks parasitize in farm animals in the northwest region of the country. The prevailing species is Rh. bursa, which constitutes 67.07 per cent of all ticks that have been collected and plays a basic role in the epizootiology of hemosporidioses. Described are the basic biotopes of the prevailing species. It has been demonstrated that altitude influences the durat-on of the seasonal activity of the parasites as well as the period during which farm animals harbour the parasites.

[Spread and economic importance of acariasis in swine]. / Razprostranenie i stopansko znachenie na akarozata po svinete.

Studies were carried out on the aspects of the epizootic process and the economic importance of acariasis in swine. It was established that the disease had widely spread. About 92 per cent of the pig-breeding farms proved infected, in which an average of 30.06 per cent of the animals showed symptoms of mange. The source of the infective agent were the diseased pigs. Infection was transmitted mainly through contact between normal and affected animals. The basic part in the epizootic process was played by sows and boars that were carriers of the parasites. Acariasis was shown to inflict heavy losses in pig farming. Acariasis-affected growing pigs gave 48.2 per cent lower weight gain as compared with intact animals of the same age.