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921.
922.
Fagen RM 《Science (New York, N.Y.)》1978,200(4342):658-659
923.
Stuiver M 《Science (New York, N.Y.)》1978,202(4372):1109
924.
925.
H. A. Westbury 《Australian veterinary journal》1978,54(7):349-351
The Australian strain of infectious bursal disease virus (IBDV), 002/73, affected the response of chickens to Newcastle disease virus (NDV). The titre of serum antibodies to NDV in chickens infected with IBDV was significantly lower than that of birds infected with NDV alone. It also appeared that IBDV affected NDV excretion from chickens as NDV was more frequently isolated from chickens infected with IBDV, IBDV infection did not alter the pathogenicity of NDV in chickens. This Australian strain of IBDV therefore appeared to be immunodepressive in one-day-old chickens. 相似文献
926.
The genital tracts of 968 slaughtered bulls (46% of which were young post-puberal animals) were examined for defects of a congenital or developmental nature. The overall occurrence of such lesions was 7%. These comprised persistent penile frenulum (0.5%), hypospadias (0.3%), detached urethral process (0.4%), testicular hypoplasia (0.2%), cryptorchidism (0.6%), mesonephric duct abnormalities (1.1%) and bulbourethral cysts, fusion and aplasia (3.6%). Segmental aplasia of the mesonephric duct, not previously recorded in the study area, was found in 4 Shorthorn bulls (0.4%); 2 affected animals were from one herd. In 3 cases of hypospadias (2 from one herd), the urethra communicated with the ventral surface of the penis at the junction of the body and glans through a slit-like orifice. The occurrence of defects observed was generally comparable to that found in bull populations elsewhere but elevated occurrence of several defects in particular herds emphasized the need for further study. 相似文献
927.
928.
Infectious avian encephalomyelitis virus (IAEV) maternal antibody was detected in the serum of chickens for up to 21 days following hatching. This antibody protected chickens against clinical IAE after intracerebral inoculation with van Roekel strain or oral administration of the NSW-1 strain of IAEV. Maternal antibody to IAEV also protected testosterone bursectomised chickens against the development of clinical disease. IAEV maternal antibody also influeced the pattern of virus excretion in faeces and serological responsiveness. This influence on antibody responses persisted beyond the time that IAEV maternal antibody could be detected. The importance of IAEV maternal antibody on the strategy of vaccination against IAE is discussed. 相似文献
929.
P J Ihrke R M Schwartzman K McGinley L N Horwitz R R Marples 《American journal of veterinary research》1978,39(9):1487-1489
Quantitative and qualitative bacterial assays were performed on the skin of 15 normal and 32 seborrheic dogs. Nonionic detergent scrubs were made on areas demarcated by glass sidearm cylinders. Quantitative analysis was accomplished by the serial dilution technique, and the bacteria were identified by individual and colonial morphology and by enzyme production. Areas measured on control dogs had a markedly lower total bacterial count than similar areas measured on seborrheic animals. Control dogs had a flora consisting primarily of coagulase-negative cocci, whereas seborrheic dogs usually had a cutaneous flora composed primarily of Stahylococcus aureus, coagulase-positive. 相似文献
930.
A bovine adenovirus with agglutinating activity was isolated from feedlot calves and classified as serotype 3. The agglutinating activity was shown to be the property of an adenovirus-associated virus (AAV). The AAV was isolated from the bovine adenovirus by isopycnic centrifugation in CsCl; the AAV had a density of 1.4 g/cm2. This AAV is serologically related to bovine AAV-TR-15, but is distinct from bovine parvovirus-1 and primate AAV types 1 to 4, using counterimmunoelectrophoresis and hemagglutination-inhibition. 相似文献