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51.
东祁连山高寒草甸灌木和牧草营养成分含量季节变化动态   总被引:4,自引:4,他引:4  
比较分析了高寒草甸和灌丛草甸中分布的几种优势牧草和灌木的营养成分,发现灌木蛋白质含量高,利用价值大,是一种重要的蛋白质饲草资源。  相似文献   
52.
The epidemiology of bovine trypanosomosis was investigated in two districts (Savelugu and West Mamprusi) of Northern Ghana with different land use and environmental characteristics. The land use intensity and environmental change was suspected to be higher in the Savelugu District. A cross-sectional entomological survey conducted along the White Volta river and its tributaries confirmed the presence of only Glossina palpalis gambiensis and G. tachinoides. The challenge index as measured by the product of tsetse density and tsetse infection rate was much higher in the West Mamprusi (19.6) than in the Savelugu district (4.7). A total of 1013 cattle (508 in Savelugu and 505 in West Mamprusi) were bled from a random selection of 16 villages in the Savelugu District and 13 villages in the West Mamprusi District. Blood samples were examined for trypanosomes by the buffy coat technique (BCT). Blood samples that were positive in the BCT or negative in the BCT but with packed cell volume (PCV) values below 21 were further tested with a polymerase chain reaction for trypanosomal DNA. Plasma samples of all cattle were serologically tested with an indirect ELISA for trypanosomal antibodies. The parasitological and serological prevalence of bovine trypanosomoses was significantly higher in West Mamprusi (16 and 53%, respectively) than in Savelugu District (8 and 24%, respectively). An evaluation of animal health at the village herd level, using PCV as an index of anaemia, provided various epidemiological scenarios prevalent in the entire study area.  相似文献   
53.
An outbreak of pulmonary adenomatosis (OPA) occurred in sheep in Patagonia, Argentina's southernmost region. On the affected farm, nine animals died over a 6-month period with pulmonary lesions of OPA. In all cases, the histology of the lungs was characterized by proliferation of cuboideal and prismatic cells lining the alveoli. Inflammatory exudates and accumulation of alveolar macrophages were marked in most cases, but in six of the cases there was no excess fluid in the airways. The presence of the Jaagsiekte retrovirus was demonstrated in the lungs by immunocytochemistry and PCR. To the best of our knowledge, this is the first report of OPA in Patagonia.  相似文献   
54.
A relatively thick (diameter approximately 2 mm), ropelike (length ca. 20 mm) and elastic "Vinculum tendinis" connects--within the fetlock tendon sheath--the dorsal side of the deep digital flexor tendon with the dorsal part of the Manica flexoria (the communicating band of the Musculus interosseous medius to the superficial digital flexor tendon). The extensive fetlock tendon sheath can be involved in diseases such as aseptic and septic inflammations. Spreading of these inflammations makes in some of these cases the partial resection of the tendon of the deep digital flexor muscle and the cutting of these Vincula necessary. The results of this contribution, collected from 60 hindlimbs of adult bovines show variations in number, length, diameter and extent and the inner structure with blood vessels and nerves.  相似文献   
55.
Radiographic measurements from the lateromedial projection of the equine foot were compared in three groups of horses. Group 1 consisted of 143 normal horses, group 2 were 60 horses with clinical navicular disease and group 3 were 161 horses with clinical and radiographic navicular disease. Several measurements tended to be larger in group 3 than group 1. An enlargement of the navicular bone was observed in proximodistal and dorsopalmar directions. Partial enlargement of the pedal bone was observed in groups 2 and 3. Few differences were observed between age classes. All horses aged four years and over had an increased length of the hoof in the dorosopalmar direction and a decrease of the cranial angle of the hoof. Enlargement of the navicular bone fits well into the concept of osteoarthrosis. The pedal bone was partly engaged. These findings may be an expression of a regional acceleratory phenomenon.  相似文献   
56.
OBJECTIVE: To determine detection rates for feline herpesvirus type 1 (FHV-1), Mycoplasma spp, fungi, and bacteria in flush samples and biopsy specimens from the nasal cavities of cats with and without chronic rhinosinusitis (CRS). DESIGN: Prospective study. ANIMALS: 10 CRS-affected cats and 7 cats without signs of respiratory tract disease. PROCEDURES: Nasal flush samples and biopsy specimens were collected from all cats for bacterial (aerobic and anaerobic), fungal, and mycoplasmal cultures; additional biopsy specimens were collected for virus isolation and polymerase chain reaction (PCR) assay (to detect FHV-1 DNA). RESULTS: Aerobic bacteria were detected in flush samples from 5 of 7 control cats; culture of flush samples from CRS-affected cats yielded aerobic bacteria (9/10 cats), anaerobic bacteria (3/10), and Mycoplasma spp (2/10). No fungal organisms were isolated from any cat. Potential pathogens were isolated significantly more often from CRS-affected cats than from control cats. Bacterial culture of biopsy specimens yielded aerobic bacteria (2/7 control cats and 4/10 CRS-affected cats) and anaerobic bacteria (2/10 CRS-affected cats). Although FHV-1 was not detected in nasal biopsy specimens from control or CRS-affected cats, FHV-1 DNA was detected via PCR assay in specimens from 4 of 7 control cats and 3 of 10 CRS-affected cats. CONCLUSIONS AND CLINICAL RELEVANCE: Compared with findings in control cats, anaerobic bacteria, Mycoplasma spp, and a variety of potentially pathogenic organisms were detected more commonly in samples from cats with CRS. In both groups, FHV-1 was detected via PCR assay as a nonviable organism or in noncultivable amounts.  相似文献   
57.
The authors studied the persistence of infection in 46 ewes experimentally infected with Brucella melitensis biovar 3 and monitored through three subsequent reproductive cycles. The entire experimental period lasted for 151 weeks. Infection of ewes and elimination of Brucella in milk, or its presence in vaginal discharges, persisted throughout the duration of the trial, as demonstrated by recurrent elimination of Brucella in milk and vaginal discharges. Brucella melitensis was recovered from the tissues of one ewe killed at the end of the trial. The strain was recovered from vaginal swabs and milk following parturition in the third reproductive cycle from an ewe that had aborted in the first cycle but was not pregnant in the second cycle. From a public health point of view, the periodical recovery of Brucella from the milk during the entire trial period illustrated that brucellosis in sheep remains a continuous occupational risk and a significant public health problem for consumers of fresh milk and milk products. That risk may persist for at least 3 years following the initial infection of the flock. Lamb antibody titres became negative in all lambs within 5 months after birth. This suggested that serological tests on lambs may have no practical diagnostic significance if performed during the first 5 months of life. Nevertheless, the birth of three infected lambs suggested that the phenomenon of latent carrier state may represent another way for B. melitensis to persist in a flock.  相似文献   
58.
A group of 160 Flemish pig farmers (n=160) were surveyed about their attitude towards surgical castration with anaesthesia (SCA) and without (SCN), immunocastration (IC), sperm sexing (SS) and the production of entire males (EM). The farmers' general preference was recorded as SCN>SS>SCA=IC>EM. The farmers' self-reported knowledge of the strategies was associated with their preference for SCA (negatively) and SS (positively). Herd size was correlated with farmers' preference for SCA (negatively) and SS (positively). Farmers perceived surgical castration without anaesthesia as the most favourable strategy in terms of farm profitability, animal performance and effectiveness against boar taint, but they expected the lowest consumer acceptance for this strategy. Surgical castration with anaesthesia was ranked the least favourable in terms of labour conditions. Production of entire males was viewed as the least profitable and the least effective strategy. Sperm sexing was positively perceived, particularly in terms of labour conditions, animal welfare, effectiveness and expected consumer acceptance. The farmers' opinion was quite homogeneous, especially regarding surgical castration without anaesthesia and production of entire males. Increasing our understanding of the farmers' perceptions will hopefully facilitate communication about this intricate issue.  相似文献   
59.
60.
BACKGROUND: Telepathology is the process of diagnostic pathology performed on digital images viewed on a display screen rather than by conventional light microscopy with glass slides. At present, electronic mail (e-mail) attachment is the most common communication medium for telepathology, because it is relatively simple and incurs minimal cost. OBJECTIVE: Our objective was to test whether telediagnosis through Internet e-mail could be applied to veterinary diagnostic cytology. METHODS: Using 20 cytology cases, on which a consensus diagnosis was reached by 3 experienced pathologists, a total of 130 images were digitized and sent as e-mail attachments from the Unit of Anatomic Pathology of the Faculty of Veterinary Medicine of Naples to the Unit of Pathology of the Faculty of Veterinary Medicine of Messina, Italy. The images were reviewed at the Unit of Pathology of Messina, where the consulting pathologist formulated his diagnoses by visualizing the images on the monitor of a computer. The telediagnoses were compared with the consensus diagnoses and with the consulting pathologist's interpretation using conventional light microscopy at a later date. RESULTS: The median time to capture images was approximately 30 minutes for each case. The median time to make a telecytodiagnosis was a few seconds for each case. Overall, there was good agreement (85%) between the consensus diagnosis and the consultant's telediagnosis. In 100% of the cases there was agreement between the consulting pathologist's telediagnosis and conventional glass slide diagnosis. CONCLUSION: Telepathology by e-mail provides acceptable efficacy and a faster turnaround time than post and can be applied to veterinary diagnostic cytology.  相似文献   
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