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991.
A serological study, using the indirect haemagglutination test, of an outbreak of toxoplasmosis in a flock of blackface sheep is described. The serological aspects of the disease are discussed with reference to this incident, and possible sources of infection are suggested.  相似文献   
992.
993.
A dog was examined because of cardiac tamponade secondary to pericardial effusion. Masses adjacent to the right atrial and ventricular walls were revealed by echocardiography. Pericardectomy and biopsies of the masses established the diagnosis of idiopathic hemorrhagic pericardial effusion with organized thrombi. The dog was healthy 3 months after surgery. These organized thrombi mimicked cardiac neoplasia echocardiographically, and such a possibility should be included in the list of differential diagnoses of cardiac masses.  相似文献   
994.
An 18-month-old neutered male Rottweiler was examined because of slowly progressive spastic tetraparesis and ataxia. Signalment and clinical signs were suggestive of 2 neuronal degenerative diseases presumed to be inherited in young Rottweilers: leukoencephalomyelopathy and neuroaxonal dystrophy. Myelography revealed an extradural compression at the articulation of the second and third cervical vertebrae. At surgery, focal hypertrophy of the yellow ligament was observed to compress the spinal cord ventrally at that site.  相似文献   
995.
Fiber types distribution in the diagastric muscle of tufted capuchin monkey was studied by means of NADH-TR, myosin-ATPase, after alkaline and acid preincubations and SDH histochemical reactions. Three different types of fibers were found presenting an equal distribution. The percentage and types of fibers were as follow: 18.2 % SO (Slow Oxydative), 38.4 % FOG (Fast Oxydative Glycolytic) and 43.4 % FG (Fast Glycolytic). FG fibers revealed the largest area. The relatively high concentration of fast twitch (81.2 %) seems to indicate this muscle is involved with the acceleration and fast speed of jaw movements. Aerobic metabolism represented by SO + FOG fibers (56.6 %) suggestes that this muscle possesses an additional role than that related to the lowering of the jaw.  相似文献   
996.
In 29 domestic hens, four blood samples were collected during the period of egg formation, at time points representing different metabolic stages. Plasma concentrations of total calcium, total phosphorus, inorganic phosphorus and total protein were measured, and the effect of adding oyster shell particles to a standard laying diet was investigated. Analyses of covariance were made and correlations between the plasma characteristics were calculated. The following were significantly correlated: total and inorganic phosphorus, calcium and total phosphorus, and calcium and protein. Each of the four characteristics showed a significant decrease during egg formation. Inorganic phosphorus reached a peak 15 h after ovulation, probably related to medullary bone resorption. Plasma total phosphorus differed significantly between chickens. Addition of oyster shell to the diet did not affect the concentration or the pattern of the plasma characteristics during egg formation and did not reduce calcium mobilisation from medullary bone during shell formation.  相似文献   
997.
Serologically negative horses, as determined with the indirect fluorescent antibody test (IFA), were infected with Babesia equi and 60 days later with Babesia caballi. The only clinical signs of disease observed in these animals were a febrile reaction and slight icterus. Haematological changes included a drop in haematocrit and haemoglobin concentration, as well as lowered platelet counts. The serum concentrations of albumin, iron and phosphorus were lowered. Mildly elevated serum bilirubin and fibrinogen concentrations were observed. Antibody titres were determined with the IFA and complement fixation (CF) tests. Antibodies to B. equi were first detected between Days 10-19 and 12-38 with the IFA and CF test, respectively, while the corresponding IFA periods for B. caballi were 6-8 days after infection. The parasitaemia of both B. equi and B. caballi infections never reached the 1% level.  相似文献   
998.
Forty-five calves on four veal calf units were monitored during the first four weeks after their arrival. Faecal samples were collected on alternate days and screened for the presence of rotaviruses, bovine coronavirus, Cryptosporidium oocysts, K99 positive strains of E. coli and Salmonella spp. Rotaviruses and Cryptosporidium were the most commonly detected agents (78% and 60% respectively of the calves). Bovine coronavirus was detected in the faeces of 18% of the calves, whilst K99 positive E. coli was only found in 2 samples from one calf. Salmonella spp. were not isolated from any of the 646 faecal samples examined. Shedding of rotaviruses occurred in a bimodal pattern beginning in the first week of the survey. Cryptosporidium oocysts were detected most frequently in the interval between the two peaks of rotavirus shedding. The presence of rotaviruses or Cryptosporidium oocysts in faeces was not strongly associated with scour, nor were combined infections with these agents or the cases of bovine coronavirus infection. The condition of the calves throughout the survey was generally satisfactory.  相似文献   
999.
The effect of intranasal vaccination of piglets with live non-AR-pathogenic Bordetella bronchiseptica (BB-) against Atrophic Rhinitis (AR) was investigated in a preliminary investigation and in a field trial. In the preliminary investigation 2-day-old SPF piglets (n = 13) were vaccinated. Three weeks after vaccination, challenges were carried out by means of a spray with an AR-pathogenic B (BB+) or an AR-pathogenic Pasteurella multocida (PM+) broth-culture. Four weeks later the piglets were necropsied and examined for atrophy of the ventral conchae (AVC). In contrast with the non-vaccinated SPF piglets, the vaccinated piglets showed a strong and significant reduction of AVC, after both BB+ and PM+ challenge. In the field trial three groups were formed by drawing lots: ten litters (82 piglets) were vaccinated; ten litters (92 piglets) formed the control group and 11 litters (104 piglets) were treated with a placebo. The litters were spread over two units. In unit 1 AR and PM+ were demonstrated incidentally, in unit 2, however, persistently. BB+ was isolated equally frequently in both units. Clinical and bacteriological examinations were done in piglets of 3, 6 and 8 weeks of age. Necropsy examinations was carried out in 41 piglets of 8 weeks of age, chosen randomly by drawing lots. In spite of a second vaccination at the age of 3 weeks, BB- was not well established; this was possibly caused by maternal BB antibodies. In the control and placebo groups PM+ was isolated earlier and more frequently than BB+. It appeared that AVC was correlated more strongly with PM+ than with BB+ infection in the field trial. The percentage of piglets with Brachygnathia superior (BS) at the age of 8 weeks indicated the AR situation in the herd. Although a significant reduction of AVC was determined in unit 2, it was not sufficient to indicate that this method of intranasal vaccination is useful in the prevention of AR in practice.  相似文献   
1000.
Six isolates of Bordetella bronchiseptica recovered from swine with atrophic rhinitis were studied. All hemagglutinated swine red blood cells, autoagglutinated in saline and showed fimbriae by electron microscopy. Hyperimmune sera against each were produced in rabbits and the antigenic relationships between the isolates were studied by cross-absorption and by the determination of the cross-reactivity indices of pairs of sera. Three isolates seemed to be identical by both methods, while 2 others showed close antigenic relationships. Hemagglutination titers with heterologous antigens and cross-reactivity indices greater than 0 suggest some degree of cross-immunity among the isolates studied, even when antigenic heterogeneity was demonstrated.  相似文献   
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