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991.
To produce large quantities of primary cell suspensions on efficient technique is described which is named "Biomix-Method". By this technique first tissue mince is performed automatically using tissue amounts between 300 g and 500 g. Trypsinization takes place in a three-litre trypsinization vessel using a stirring mechanism according to a defined trypsinization mode. In regard to optimal cell seeding concentration and a justifiable productivity one kidney of newborn or suckling calf yields 6--9 1 cell suspension and that of piglet 1,8-2,3 1, respectively. Proliferation behaviour and effectivity of primary cells are discussed and compared with other cell systems.  相似文献   
992.
A 10-month-old male domestic short-haired cat was examined because of progressive lameness, a broad face with depressed nasal bridge, small ears, corneal clouding, and multiple bone dysplasia. The cat excreted excessive amounts of glycosaminoglycan (a component of connective tissue) in its urine and had evidence of lysosomal storage of glycosaminoglycans in fibroblasts and neurons. Activity of alpha-L-iduronidase, a lysosomal enzyme involved in glycosaminoglycan degradation, was deficient in cultured fibroblasts and leukocytes. The mucopolysaccharidosis was distinct from that seen in Siamese cats in terms of the pathologic changes and the specific enzyme deficiency.  相似文献   
993.
Virus was isolated from semen and fecal samples from a bull with orchitis, testicular degeneration, aspermatogenesis, and loss of libido. Both isolates were classified as picornavirus, bovine enterovirus serotype I, on the basis of physical, chemical, and serologic characteristics. Veterinary practitioners that may suspect viral infection as a cause of bovine infertility should submit both semen and fecal samples for virus isolation and identification.  相似文献   
994.
995.
An 11-month-old male Miniature Poodle was found to regurgitate small volumes of fluid and food particles due to a diverticulum in the thoracic oesophagus. The diverticulum was removed surgically. Histologically the wall contained extensive scar tissue. Longterm recovery was uneventful and 5 months after surgery the dog is in good health  相似文献   
996.
997.
This serologic study was done to gain information on the spread, maintenance, and effect upon performance of five porcine viruses. Blood samples were taken from two groups of 8- to 11-week-old pigs from a large number of Indiana swine herds in a performance-testing station 1 week after entry, 7 weeks after entry (one group only), and at slaughter. The sera were tested by indirect fluorescent antibody tests for antibodies to transmissible gastroenteritis virus (TGEV), swine influenza virus (SIV), hemagglutinating encephalomyelitis virus (HEV), porcine adenovirus (PAV), and pseudorabies virus (PRV). Seroconversions to TGEV, HEV, and PAV occurred in a group of pigs entered in May and slaughtered in August (group 1). In the group that was entered in October and slaughtered in January (group 2), pigs developed antibodies to SIV, HEV, and PAV, but not to TGEV. Only 1 of the 434 pigs tested had antibodies to PRV, and there were no seroconversions to this virus. The only statistically valid effect of infection on performance was found in group 1 pigs, which had seroconverted to TGEV during the first 7 weeks of their stay. These pigs gained 0.077 kg less per day than pigs that did not develop antibodies to TGEV during that period. The pattern of serologic reactions was indicative of a relatively slow spread of these viruses in the groups. We interpret this as supporting the concept that a relatively slow spread of these viruses through large groups of pigs kept under conditions that are less than optimum for virus spread may be an important means of their interepizootic survival.  相似文献   
998.
Fourteen neonatal dogs (4 through 11 days of age) were exposed orally to the Purdue strain of transmissible gastroenteritis (TGE) virus, and six dogs of similar age were noninoculated controls. Clinical signs of enteric disease did not develop. Both exposed and control dogs had normal fecal passages and appetite throughout the experiment. Jejunal epithelium from dogs euthanatized at 12, 24, 48, and 96 hours and at 10 days after exposure did not exhibit morphologic alterations detectable by light microscopy. Electron microscopic examination indicated that jejunal epithelial cells contained TGE viral particles as early as 12 hours after dogs were exposed. There were no apparent morphologic alterations or signs of desquamation of virus-infected cells, however. Results of pig transmission studies indicated that viable TGE virus was in jejunal tissue of the dogs as early as 12 hours and as late as 10 days after exposure to the virus.  相似文献   
999.
Cell-mediated immune responses in cattle adult-vaccinated with Brucella abortus strain 19, cattle infected with B abortus field strain, and nonexposed cattle were studied by an in vitro lumphocyte-stimulation test (LST). Lymphocytes were prepared from peripheral bovine blood by the Ficoll-diatrizoate technique, and results were assayed for [3H]thymidine incorporation into DNA by liquid scintillation spectrometry. Serotests and bacteriologic isolation attempts were conducted simultaneously with LST. Lymphocytes from cattle infected with field strains had significantly (P = 0.01) higher specific lymphocyte-stimulation inexposed controls. The LST, the serum standard-tube agglutination test (STT), the Rivanol (RIV) test, and the complement-fixation (CF) test correctly classified cattle from which field strains and strain 19 of B abortus were isolated. The LST was negative in cattle vaccinated with B abortus strain 19 (nonshedding), but the three serotests had many false-positive reactions. The CF test had the least false-positive reaction, followed by the RIV test, and the STT was the least specific. Well before the three serotests became positive, the LST was positive in samples from some cattle during the incubation period of the infection. There was little or no correlation between cell-mediated immune responses (as measured by LST) and serum antibody responses (as measured by STT, RIV test, and CF test) in vaccinated but culture-negative cattle and in some nonvaccinated cattle during the incubation period.  相似文献   
1000.
Naturally acquired Brucella abortus infections were studied during consecutive pregnancies in eight sheep and in their lambs over a period of 40 months to evaluate epizootiologic aspects of natural infection in sheep. Brucella abortus was isolated from the ewes following 16 of 26 natural terminations of pregnancy: from 5 of 6 ewes in the first year, from six of eight ewes in the second year, from two of six ewes in the third year, and from three of six ewes in the fourth year. Vaginal swab samples and milk samples were the most consistent source of the brucella organisms. Brucella abortus was isolated from three ewes when standard tube test seroagglutination titers were less than 1:100. In contrast, results of supplemental tests (card, 2-mercaptoethanol, complement-fixation, and Rivanol) remained positive during the study. During the 40 months, B abortus was isolated from 4 of 4 aborted fetuses, 2 of 5 stillborn lambs, 10 of 37 living lambs, and as an indicator of continuing infection, from 6 of 12 lambs born during the fourth year. Although B abortus has a definite host preference for cattle, this study demonstrated that under appropriate management conditions, sheep may be naturally infected and may remain infected for more than 40 months. Epizootiologic evaluation of all factors, including husbandry practices and exposure potential, should be utilized in determining the need to test other species that may have been exposed to cattle infected with B abortus.  相似文献   
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