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991.
Congenital cataracts and microphthalmia in the Miniature Schnauzer were inherited as an autosomal recessive trait. Eighteen matings of affected X affected Miniature Schnauzers resulted in 87 offspring with congenital cataracts and microphthalmia (49 males/38 females). Two matings of congenital cataractous and microphthalmic Miniature Schnauzers (2 females) X a normal Miniature Schnauzer (1 male) yielded 11 clinically normal Miniature Schnauzers (7 males/4 females). Eighteen matings of congenital cataractous and microphthalmic Miniature Schnauzers (6 males) X carrier Miniature Schnauzers (9 females) produced 81 offspring; 39 exhibited congenital cataracts and microphthalmia (20 males/19 females) and 42 had clinically normal eyes (17 males/25 females).  相似文献   
992.
Since the normal absorption of CSF occurs in the cerebral veins and venous sinuses, any obstruction to the normal flow and absorption of CSF will result in accumulation of CSF central to the site of obstruction. Such accumulation within the cranium is defined as hydrocephalus.A foal was presented with an enlarged and an abnormally-shaped skull, but with normal behavior. The filly's condition deteriorated. Radiographs showed a domeshaped cranial vault with compression of the frontal sinus region. Massive hydrocephalus with little normal cerebral tissue left was diagnosed with ultrasound.Surgery was attempted to relieve the pressure. Eventually the foal was euthanized. Post-mortem confirmed the radiographic and ultrasound diagnosis. Since there was a lack of demonstrable obstruction, the authors suspected the foal had suffered from the Arnold-Chiari syndrome.  相似文献   
993.
A nine-year-old Arabian gelding was evaluated for acute abdominal pain. Based on clinical signs and the results of the diagnostic work-up, surgical exploration of the abdominal cavity was performed. An adhesion was found involving a section of jejunum, its mesentery, and the omentum. Passage of gas and/or ingesta was obstructed at that point. On closer examination of the involved bowel, a porcupine quill which had perforated throught the intestinal wall from the lumen was identified. This was believed to have been the inciting cause for the formation of the adhesion and subsequent intestinal obstruction.  相似文献   
994.
1. Broilers were fed on wheat‐casein or wheat‐soyabean meal diets and the excreta collected after 12 and 24 h. Samples of excreta were freeze dried or dried in a force draught oven at 60 or 80 °C.

2. Drying procedure and collection time significantly influenced the determined energy and nitrogen concentrations of the excreta.

3. Drying excreta in an oven at 60 °G proved at least as effective as freeze drying for the majority of amino acids.  相似文献   

995.
Inhibitory effect of the bovine conceptus on lymphocyte stimulation   总被引:1,自引:0,他引:1  
Experiments were conducted to determine whether the preimplantation bovine conceptus produces an immunosuppressant as measured by the inhibition of lectin-induced incorporation of thymidine into lymphocytes. The results of the experiments clearly indicated that media from cultured 18-d-old embryos inhibited lectin-induced incorporation of thymidine into bovine lymphocytes. The inhibitory substance was not produced by heat-killed cells from the conceptus, was not toxic to lymphocytes, was not lectin-specific, but did act in a partially reversible manner. The inhibitor had no apparent effect on porcine lymphocytes, a moderate effect on ovine lymphocytes and a potent effect on bovine lymphocytes. The substance appeared to have a molecular weight of between 500 and 10,000 and was ether insoluble and heat stable. The possible chemical nature of the inhibitor and its potential effect on survival of the preimplantation conceptus are discussed.  相似文献   
996.
Polyacrylamide gel electrophoresis was used to compare serum taken from ponies before and during clinical illness confirmed as grass sickness. A consistent rise in the level of haptoglobin was seen in serum from animals which had shown symptoms for more than two days. Serum albumin was also shown to have altered mobility at the onset of clinical disease. Estimation of the haemoglobin-binding capacity confirmed the haptoglobin increase. This haptoglobin has been purified and some of its properties determined. In contrast to the situation in acute inflammatory conditions no other acute-phase proteins increased to a significant extent in grass sickness. It is concluded that the neurotoxin known to be present in sera of animals experiencing acute grass sickness cannot itself be detected by polyacrylamide gel electrophoresis but may be bound to serum albumin.  相似文献   
997.
Twenty-one experimental oil-emulsion vaccines with different emulsifier contents, aqueous-to-oil ratios, and antigen concentrations were compared by immunization of 4-week-old chickens. Vaccines that contained oil-phase (Arlacel 80) and aqueous-phase (Tween 80) emulsifiers induced 2-to-4-fold higher hemagglutination-inhibition titers than vaccines with only the oil-phase emulsifier. The emulsion vaccines containing both emulsifiers were also more stable at 37 C and less viscous than those containing only the oil-phase emulsifier. Vaccines that had different aqueous-to-oil ratios and contained different quantities of allantoic-fluid antigen (1.2% to 50% of the vaccine volume) induced similar protection against challenge, but hemagglutination-inhibition titers were proportional to the amount of antigen added. Vaccines that had different aqueous-to-oil ratios but contained equal amounts of antigen induced similar hemagglutination-inhibition titers and similar protection against challenge.  相似文献   
998.
A 31-year-old captive male African elephant (Loxodonta africana) of 5,000-kg body weight died suddenly in ventral recumbency. Lesions seen at necropsy were bilateral purulent pulpitis and periodontitis of both tusks, serous atrophy of coronary groove fat, Grammocephalus cholangitis, myocardial and skeletal lipofuscinosis, and scattered segmental necrosis in the pectoral muscles. Nonhemolytic streptococci, Corynebacterium sp, Peptostreptococcus anaerobius, Fusobacterium nucleatum, and Bacteroides sp, were recovered from the exudate around one or both tusks. We postulated that the elephant died of hypoxia from prolonged ventral recumbency because of weakness and inability to rise secondary to toxemia from bilateral pulpitis and periodontitis.  相似文献   
999.
Praziquantel was evaluated for its larvicidal activity against naturally or experimentally induced Taenia hydatigena infections in sheep. The major criterion used for assessing efficacy was an estimate of the dose rate required to free 90 per cent of the sheep from infection (ED90) together with a 95 per cent confidence interval. With both light and heavy infections of three-month-old T hydatigena in lambs up to 12 months old, many larvae were killed. The ED90 and 95 per cent confidence limits for six-month-old and aged organisms was estimated to be 13.1 (5.5 to 31.4) mg/kg and 6.1 (2.4 to 15.5) mg/kg, respectively. Equivalent data for the ED50 were 3.4 (1.4 to 8.3) mg/kg and 1.3 (0.3 to 5.4) mg/kg, respectively. It was established that one of the factors involved in the efficacy of praziquantel was associated with the age of the larvae at the time of treatment, the drug being markedly more effective against older than younger organisms.  相似文献   
1000.
A simple technique is described for the isolation of Toxoplasma gondii tissue cysts from fetal ovine brain by centrifugation on a discontinuous density gradient of 30 per cent and 90 per cent Percoll (colloidal silica solution). Brain samples from 51 aborted ovine fetuses were examined by both the Percoll and mouse inoculation techniques; eight infections were detected by the Percoll technique compared to 12 by mouse inoculation. Possible reasons for this discrepancy and the scope for improving the Percoll technique are discussed.  相似文献   
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