ABSTRACT
A Finnish material of 455 cloacal specimens from 24 species of small migratory birds and of 54 cloacal specimens from 10 species of waterfowl was investigated for the occurrence of A type influenza virus. Influenza A virus was isolated in only one specimen, originating from a mallard (Anas platyrhynchos). Parallely, yolk material from 109 waterfowl representing 9 species was investigated for the occurrence of influenza A antibodies by complement fixation and immunodiffusion tests. In three yolk specimens, one from a widgeon (Anas penelope), one from a common gull (Larus canus) and one from a lesser blackbacked gull (Larus fuscus), positive reactions with low titres of 1:2--1:4 were obtained. The study shows that waterfowl can carry influenza A virus, but the role of small migratory birds in this respect seems to be negligible in Finland.
Subject(s)
Antibodies, Viral/analysis , Birds/microbiology , Influenza A virus/immunology , Animals , Birds/immunology , Cloaca/microbiology , Finland , Influenza A virus/isolation & purificationSubject(s)
Pneumonia, Progressive Interstitial, of Sheep/pathology , Sheep/microbiology , Animals , Brain/microbiology , Female , Lung/microbiology , Lung/pathology , Lymphocytes/microbiology , Male , Microbiological Techniques , Respiratory System/microbiology , Time Factors , Visna-maedi virus/isolation & purificationABSTRACT
The effect of artificial air-ionization on air-borne transmission of Newcastle disease virus (NDV) infection in chickens was studied in an isolated system consisting of two side-by-side cages with solid walls and a wire-gauze roof. During a 3-week observation period more than 90% of the uninoculated indicator chickens, housed in one of the cages, contracted the virus shed to the air by the NDV-inoculated, diseased birds in the neighbouring cage. This air-borne transmission of NDV was completely prevented by increasing the ion concentration in the test room by a constant negative corona discharge above the wire-gauze roof. On the other hand, spreading of the infection within a group of chickens housed in a single cage was not affected by air ionization. These and other results suggest that artificial air-ionization may protect animals from certain air-borne infections by interfering with microbial aerosol formation and/or by facilitating their decay.
Subject(s)
Air Ionization , Chickens , Newcastle Disease/transmission , Poultry Diseases/transmission , Air Microbiology , Animals , Newcastle Disease/prevention & control , Poultry , Poultry Diseases/etiology , Poultry Diseases/prevention & controlABSTRACT
In 1974, a very extensive influenza/A/equi 2 epidemic broke out in the Finnish horse population. To study the efficacy of influenza vaccinations a questionnaire was sent after the epidemic to all Finnish veterinarians. The answer material was selected to contain only stables which had had clinically typical cases. The material consisted 234 unvaccinated and 629 vaccinated horses. In the latter group 466 horses were vaccinated adequately. The results of the study showed that of the unvaccinated horses 212 (91%) and of the adequately vaccinated horses only 42 (9.4%) contracted clinically typical influenza. On the other hand, in the group of horses vaccinated irregularly or only once before the epidemic the disease prevalence was about the same as for the unvaccinated animals. Thus, the equine influenza vaccines used in Finland had a surprising good efficacy if they were used according to instructions.
Subject(s)
Horse Diseases/prevention & control , Influenza Vaccines , Orthomyxoviridae Infections/veterinary , Animals , Finland , Horses , Orthomyxoviridae Infections/prevention & control , Vaccination/veterinaryABSTRACT
Infection with Mycoplasm pulmonis caused a slight increase in the incidence of chromosome breaks in goniomitotic cells of the rat testis. No differences existed between healthy and infected rats in the frequency of mitotic divisions, measured as the number of metaphases per slide. The macrolide antibiotics erythromycin and tylosin are widely used as antimycoplasmal drugs. Erythromycin was given to healthy rats intramuscularly at a concentration of 20 mg/kg, and tylosin perorally in the drinking water at a concentration of 0.1%, both for 10 days. Neither drug induced an increase in the incidence of chromosome breaks in the spermatogonia. But both these macrolides caused a definite reduction in the therapy of cell division. With erythromycin, this effect had disappeared 18 days after the end of treatment.
Subject(s)
Anti-Bacterial Agents/pharmacology , Chromosome Aberrations , Chromosomes/drug effects , Erythromycin/pharmacology , Leucomycins/pharmacology , Mitosis/drug effects , Mycoplasma Infections , Spermatogonia/drug effects , Spermatozoa/drug effects , Animals , Male , Mycoplasma Infections/genetics , RatsSubject(s)
Antigens, Viral/analysis , Avian Leukosis/diagnosis , Chickens/immunology , Germ-Free Life , Specific Pathogen-Free Organisms , Alpharetrovirus/immunology , Animals , Antibodies, Viral/analysis , Avian Leukosis/immunology , Avian Leukosis Virus/immunology , Avian Sarcoma Viruses/immunology , Chick Embryo , Cricetinae/immunology , Epitopes , Immunization , RadioimmunoassayABSTRACT
Ten Finnish breeding flocks were investigated for occurrence of avian leukosis virus and antibodies. The results show that field isolates representing all 4 main subgroups, A, B, C, and D, of avian leukosis virus have been identified. Antibodies to these subgroups are widespread in the country. Within 5 of the flocks antibody response to all 4 subgroups was found simultaneously, and there were individual chickens that carried antibodies against 2, 3, and in 2 cases, even, all 4 subgroups at the same time.
