[Effect of the bacterial count in the air on chickens and laying hens raised commercially].

Investigations were carried out to establish the amount of bacteria in the air on the premises for raising young birds and laying hans as well as in the respiration organs of the birds. Attempts were made to lower the microbism on the premises through the aerosol spray of Lugol solution. It was found that under industrial conditions there existed a rising trend with microbism both on the premises and in the respiratory organs of the birds, parallel to the advance in age which contributed to the enhancement of mortality rate and the drop of productivity.

[Pharmacokinetic research and the ultrastructural changes in the lungs of white rats after aerosol administration of a high dose of kanamycin sulfate].

Studied is kanamycin sulphate "Pharmachem", substance with activity 750 UI/mg, applied on albino rats in the form of water aerosol. The experiments are carried out in aerosol camera of flow-dynamic type with capacity 450 l at exchange of the air 60 l/min with aerosol apparatus of pneumatic type, for 10 min and staying in the aerosol cloud another 10 min. It is established that the kanamycin sulphate, after aerosol application on albino rats in dose of 50000 UI/m3, passes in the blood and is found out in the serum yet in the first hour (1.

[A pneumatic-type aerosol apparatus for veterinary uses].

Described is a Bulgarian aerosol apparatus of pneumatic type with an original nozzle and way to maintain permanent pressure. The apparatus is supplied with a set of 7 nozzles of a varying dia and is intended for universal dispersion of veterinary preparations and vaccines in aerosol form in view of their dosing. It makes it possible to maintain the desired concentration of the preparation sprayed for several minutes.

[Newcastle disease virus carrier state following the aerosol immunization of chickens against the disease using different doses of La Sota vaccine].

Six experiments were carried out with aerosol immunization, using various doses of the La Sota vaccine against Newcastle disease, and a control infection with massive amounts of the viscerotropic virus strain Pavlikeni to evaluate the duration of carrying the Newcastle disease virus. The aerosol vaccination of the birds was performed in laboratory conditions in an aerosol chamber of a flow-dynamic type of 450 l. The amount of the virus in the aerosol was determined through virologic investigations of samples taken by means of a glass capillary impinger.

[Newcastle disease virus carrier state after aerosol vaccination against the disease in chickens of various ages].

Studied was the carrier status with the Newcastle disease virus in experiments with a total of 665 birds at the age of 10 days, one month, and two months following an aerosol vaccination with a La Sota strain vaccine as well as the possibility to isolate the velogenic strain Texas GB after control infection of 10-day-old and one-month-old birds. Established was a short-term carrier status with the La Sota strain in the organs of birds up to the 6th-9th day following the aerosol vaccination. In an experiment with month-old birds originating from parental flocks immunized against Newcastle disease the La Sota virus was isolated also from the brain up to the sixth day.