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Plasma beta-mannosidase activities were determined for Salers cattle from 8 herds as an evaluation of this method for detection of beta-mannosidosis heterozygotes. Several biological factors, such as age, gender, herd, and risk of being a beta-mannosidosis carrier, were considered in this study. The mean enzyme activity for obligate heterozygotes (n = 8) was 55 U/ml (range = 43-65 U/ml), which was 59% of the mean enzyme activity for cattle that were low risk for being a carrier. These data indicate that bovine beta-mannosidosis is characterized by a gene dosage effect. The analytical and biological variation of plasma beta-mannosidase activity that was observed necessitates limiting the test to adult fullblood/purebred Salers cattle within a herd. Plasma beta-mannosidase analysis provides important information for intraherd selection of Salers cattle that are heterozygous for beta-mannosidosis.  相似文献   
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The tendency of trauma to the eye, especially in the cases of infected perforating wounds or of parasitic infections, to involve all structures of the eye, is outlined and the need for surgical treatment is discussed. Difficulties and problems in operative procedures arising from the varied manifestations of panophthalmitis, particularly with regard to anaesthesia, immobilization, excision and resection of tissues, drainage and postoperative dressings, and the methods of overcoming them, are described on the basis of nineteen surgical cases.  相似文献   
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A field grazing trial was undertaken to monitor the health and production of crossbred sheep grazing pasture where Echium plantagineum constituted a considerable proportion of the available forage. The trial, conducted for 19 months over successive grazing seasons, demonstrated a significant difference in production, with sheep on the E. plantagineum pasture being lighter and growing less wool compared with sheep on Echium-free pasture. No mortalities involving pyrrolizidine alkaloid poisoning were recorded in sheep grazing E. plantagineum, although there was histological evidence of moderately severe liver damage associated with high liver copper concentrations in at least one sheep following the grazing of large quantities of the plant.  相似文献   
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Variable pathways of lymphatic drainage have been described in the dog head and neck. The aim of this study was to retrospectively assess the patterns of lymph node metastasis in dogs with malignancies of the head following bilateral mandibular and medial retropharyngeal lymphadenectomy. Thirty‐one dogs were included. Median age at surgery was 10 years (range: 5 months to 14 years) and mean bodyweight was 21.4 ± 11.9 kg. Lymph node metastasis occurred in 14 dogs (45%), with spread to mandibular lymph nodes in 14 dogs and medial retropharyngeal metastasis in 11 dogs. Eight of 13 dogs (62%) with lymphatic metastasis and a lateralised lesion showed contralateral dissemination, while 12/13 (92%) showed ipsilateral metastasis. Of 13 dogs with oral malignant melanoma, four showed metastasis to all four lymph centres. Contralateral metastasis may occur in dogs with malignancies of the head and should be considered during staging and management.  相似文献   
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