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51.
Six pieces of grafts, 6.5 mm in diameter, 20 mm in length, were taken from each of 170 cadaver hindlimbs, using the cranial surface of the medial femoral trochlea for harvesting. The age of the horses varied between 4 months and 23 years. 30 limbs under the age of 12 years were selected for transplantation. Three of six grafts were transplanted into the medial femoral condyle using different combinations of tunnel depth and dilation. With ageing, a significant decline in transplantability was detected. In general, mosaicplasty cannot be recommended in horses above 11 years. Based on a previous clinical case (Bodó et al., 2000), a good surface alignment was indeed achieved with a combination of graft length drilling and dilation in most cases. However, the occasional entrapment of cartilage debris under the graft prevented perfect alignment in the present cadaver study in 27% of the grafts transplanted in this manner. Since the protrusion of grafts never exceeded 1.5 mm, we conclude that drilling 3-5 mm deeper than graft length with graft length deep dilation can avoid disadvantageous protrusion of the transplanted hyaline cartilage caps, achieving bone decompression at the same time.  相似文献   
52.
Trypanosoma evansi is the most widely spread of the pathogenic African trypanosomes of animals. The disease (surra) was first diagnosed in the Canary Islands in a dromedary camel in 1997; thus, a control plan was implemented achieving the eventual eradication of T. evansi from most of the infected areas in the Archipelago. However, a little area remains still infected despite the use of the same control measures. To evaluate possible reservoirs in the area a representative sample of domestic ruminants was examined by serological, parasitological and molecular tests. Of a total of 1228 ruminants assessed, 61 (5%) were serologically positive (7 cattle, 21 goats, 33 sheep), but T. evansi could be demonstrated in none of them. According to FreeCalc assessment, cattle and goat populations would be free from disease; however, the results from sheep are not adequate to conclude that the population would be free from disease. As a conclusion, surveillance must be exercised on ruminant farms in the surroundings of the infected area in order to evaluate the possible extension of the disease and their potential role as reservoirs of T. evansi.  相似文献   
53.
54.
A 6-year-old female Alaska Malamute dog was presented for evaluation of abdominal enlargement referred by a local veterinarian. On the history, the owner complained of chronic abdominal enlargement initiated more than 4 months ago, reduced appetite, occasional vomiting and general dullness. He also complained of greenish mucous intermittent vaginal discharge starting 10 days ago. The bitch was chronically treated with medroxiprogesterone acetate. A laparatomy was performed and fluid in the abdomen was found and aspirated during the surgery. Also a very fluid-filled distended uterus and a mass in the distal part of the left uterine horn were found. The mass was encapsulated by the omentum, but areas of necrosis and calcification were identified. Histopathological diagnosis was endometrial adenocarcinoma.  相似文献   
55.
REASONS FOR PERFORMING STUDY: Danofloxacin is a fluoroquinolone developed for veterinary medicine showing an excellent activity. However, danofloxacin pharmacokinetics profile have not been studied in horses previously. OBJECTIVE: To study the pharmacokinetics following i.v., i.m. and intragastric (i.g.) administration of 1.25 mg/kg bwt danofloxacin to 6 healthy horses. METHODS: A cross-over design was used in 3 phases (2 x 2 x 2), with 2 washout periods of 15 days (n = 6). Danofloxacin (18%) was administered by i.v. and i.m. routes at single doses of 1.25 mg/kg bwt. For i.g. administration an oral solution was prepared and administered via nasogastric tube. Danofloxacin concentrations were determined by HPLC assay with fluorescence detection. Tolerability at the the site of i.m. injection was monitored by creatine kinase (CK) activity. RESULTS: Danofloxacin plasma concentration vs. time data after i.v. and i.g. administration could best be described by a 2-compartment open model. The disposition of i.m. administered danofloxacin was best described by a one-compartment model. The terminal half-lives for i.v., i.m. and i.g. routes were 6.31, 5.36 and 4.74 h, respectively. Clearance value after i.v. dosing was 0.34 l/kg bwt/h. After i.m. administration, absolute bioavailability was mean +/- s.d. 88.48 +/- 11.10% and Cmax was 0.35 +/- 0.05 mg/l. After i.g. administration, absolute bioavailability was 22.36 +/- 6.84% and Cmax 0.21 +/- 0.07 mg/l. CK activity following i.m. dosing increased 3-fold over pre-injection levels 12 h after dosing and subsequently approached (but did not reach) normal values at 72 h post dose. CONCLUSIONS: Systemic danofloxacin exposure achieved in horses following i.m. administration was consistent with the predicted blood levels needed for a positive therapeutic outcome for many equine infections. Conversely, danofloxacin utility by the i.g. route was limited by low bioavailability. Tolerability associated with i.m. administration was high. POTENTIAL RELEVANCE: Pharmacokinetics, blood levels and good tolerability of i.v. and i.m. administration of danofloxacin in horses indicates that it is likely to be effective for treating sensitive bacterial infections.  相似文献   
56.
Four farms that group-housed sows from 2 weeks of lactation until weaning (G-farms) and 3 farms that kept the sows individually penned throughout the 5 to 6-week-long lactation period (C-farms), were compared in terms of sow health. All sows were crossbred Swedish Yorkshire × Swedish Landrace. The daily food ration was similar on all farms except during the group-housing period, when G-farm sows were fed ad libitum. Sows were grouped in the breeding section and kept grouped on deep litter in the dry sow section on all farms. Individual health examinations were performed at the time of weaning (±4 days) on 179 G-farm sows and on 167 C-farm sows. Teat- and udder skin wounds occurred less frequently (p<0.001) in G-farm sows than in C-farm sows. In addition, preweaning atrophy of all mammary glands occurred in 6.6% of the G-farm-sows but not in a single C-farm sow (p<0.001). This indicates that sow-piglet interactions decrease when sows are group housed. However, these differences did not occur in primiparous sows, suggesting that the relation between the primiparous sow and her litter is not affected. Mastitis frequency was the same in the 2 systems. Moreover, the frequency of locomotor disorders was the same in the 2 groups, and hoof overgrowth was common in both systems. These similarities could be due to the fact that all farms group housed dry sows on deep litter. A strong relation (p<0.001) between hoof overgrowth and locomotor disorders was evident. Low access to food due to low rank among primiparous group-housed sows was indicated by a lower (p<0.05) backfat thickness compared with multiparous sows, and a higher (p<0.001) frequency of skin wounds compared with individually housed primiparous sows.  相似文献   
57.
This study examines the effect of L-carnitine (LC) on chilled ram semen stored for up to 96 hr. Semen samples were collected, placed in a skimmed milk + 6% egg yolk extender, pooled, aliquoted and diluted with the same extender supplemented with different LC concentration: 0 (control), 1 mM (LC1), 2.5 mM (LC2.5), 5 mM (LC5), 7.5 mM (LC7.5) or10 mM (LC10). Sperm kinetics and membranes (plasma, acrosome and mitochondrial) were examined using the CASA system and triple fluorescence staining (PI/ PNA-FITC/Mitotracker). The progressive motility was greater (p < .05) with LC7.5 treatment than the control sperm at 96 hr. The curvilinear velocity (p < .01) and the percentage of sperm with intact membranes (plasma/acrosome/mitochondria) (p < .01) were greater with all LC treatments than the control group at all times. Straight line velocity was greater (p < .01) with LC5 and LC7.5 treatments than the control group after 48 hr. The LC5 group also returned lower ALH values (p < .05) than these seen for the control groups after 48 hr. The fertilizing capacity of LC5 samples stored at 15°C for 2 hr (LC5-15°C-2h) and at 5°C for 24 hr (LC5-5°C-24h) was tested in three ewe groups via cervical fixed-time artificial insemination. In two groups, the fertilizing capacity of the LC5-5°C-24h was reduced (p < .001). In the remaining group, however, no significant difference was seen between the LC5-15°C-2h and LC5-5°C-24h sperm in this respect (pregnancy rates 52.4% versus 42.8%; p > .05). Overall, the present results suggest that supplementing skimmed milk–egg yolk-based extenders with LC has a positive effect on chilled sperm variables and fertilizing capacity.  相似文献   
58.
59.
Though the armadillo is important as a research model in leprosy studies, the activity of armadillo's neutrophils is an aspect of little research. The aim of this study was carried out to partially characterize the chemotaxis, endocytosis and bacteriocidal ability of the neutrophils found in the nine-banded armadillo (Dasypus novemcinctus). Results showed that the chemotactic activity of the neutrophils, evaluated by the movement of the neutrophils through a nitrocellulose membrane (5 microm) in response to a chemo-attractive substance, was greater towards the armadillo serum (5.16+/-1.35 migration index, p<0.05) than towards the formil methionyl leucil phenylalanine (fMLP, 1.43+/-0.18 migration index) or human serum (0.56+/-0.18 migration index). Regarding endocytic capacity of the neutrophils and the monocytes against Escherichia coli was evaluated by a flow cytometry and using opsonized and non-opsonized E. coli-FITC at the following incubation times: 5, 10, 20, 30 and 60 min. The largest percentage of endocytosis by the neutrophils was 92.32+/-0.12% with opsonized bacteria and 77.73+/-14.33% with non-opsonized bacteria at 10 min incubation time, while the largest percentage of endocytosis by monocytes was 89.94+/-1.40% with opsonized bacteria and 73.07+/-15.6% with non-opsonized bacteria at 20 min incubation time. Evaluation of the bacteriocidal capacity of neutrophils using the methyl-thiazol-tetrazolium salts (MTT) reduction color-measurement assay showed an 89.0+/-10% mortality rate of non-opsonized E. coli and 89.0+10% of opsonized E. coli. In conclusion, the armadillo neutrophils show a good phagocytosis and bacteriocidal activity; however, a deficiency in the migration towards the fMLP was observed. This deficiency could be a cause so that the armadillo neutrophils do not respond quickly to invading microorganism.  相似文献   
60.
Spontaneous and experimental poisoning with the swainsonine-containing and calystegine-containing plant Ipomoea carnea subsp fistulosa is described. Three of 8 goats presenting with emaciation, weakness, symmetrical ataxia, posterior paresis, proprioceptive deficits, abnormal posture, abnormal postural reaction, and muscle hypertonia were necropsied. I fistulosa was suspected to be the cause of the neurologic disease in all cases. An experiment was conducted to confirm the diagnosis using 12 goats and diets containing 3 different concentrations of the plant. All goats fed I fistulosa developed neurological signs that were similar to those observed in the spontaneous intoxication. Muscle atrophy and pallor were the only macroscopic changes observed in spontaneous and in experimental intoxication. Histological lesions of spontaneous and experimental animals were similar. The most prominent lesion was cytoplasmic vacuolation in neurons of the central and the autonomous nervous system, pancreatic acinar cells, hepatocytes, Kupffer cells, follicular epithelial cells of the thyroid gland, and macrophages of the lymphatic tissues. Neuronal necrosis, axonal spheroids formation, and astrogliosis were additionally observed in the brain. Ultrastructurally, the cytoplasmic vacuoles consisted of distended lysosomes surrounded by a single-layered membrane. Nonreduced end-rests or sequence of alpha-Man, alpha-Glc, beta(1-4)-GlcNAc, and NeuNAc on lysosomal membrane were revealed by lectin histochemistry. Samples of plants used in the experimental trial contained swainsonine and calystegine and their intermediary derivate. We conclude that I fistulosa induces a glycoprotein storage disease primarily based on the inhibition of the lysosomal alpha-mannosidase by the alkaloid swainsonine.  相似文献   
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