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91.
This study evaluated onset and incidence of palmar process fractures in foals and investigated corresponding changes in hoof conformation. Radiographs of 17 warmblood foals were taken at 1 week and at 2, 4, 6, 8, and 12 months of age and examined for evidence of palmar process fractures. Hoof parameters were measured from the radiographs, and comparisons were made between fractured and nonfractured feet. All foals suffered at least one fracture during the study period, with an average age of 3.68 ± 0.20 months at fracture occurrence. Hoof conformation and fracture occurrence were not significantly correlated. Foals consistently demonstrated higher lateral heights in the right foot and higher medial heights in the left foot. Hoof angle increased until 3 months of age and then gradually dropped. Hoof-pastern axis exhibited a broken forward conformation, but approached a more correct conformation by 12 months of age. There was a significant reduction in variation of variables for hoof and pastern angle in both feet, and hoof-pastern axis in the right foot. Hoof conformation does not appear to be a causative factor of palmar process fractures. It is possible that these fractures are a normal part of bone remodeling.  相似文献   
92.
Medical records of 27 cats with masses of the larynx and trachea were examined. Six cats had inflammatory masses, and 21 cats had neoplastic lesions. A definitive diagnosis was reached in 22 cats with a single biopsy. The median age of the cats was 12.0 years (range 6 to 20 years). Dyspnea was the most common clinical sign. Accurate diagnoses were best obtained through direct laryngeal or tracheal examination combined with histological examination of tissue biopsies. Kaplan-Meier survival data for all inflammatory and neoplastic lesions showed a median survival of 5 days, with 7.4% of cats alive at 1 year.  相似文献   
93.
Thiafentanil oxalate, previously known as A-3080, is a synthetic opioid used for chemical immobilization of a variety of nondomestic hoofstock species. This study compared the combination of thiafentanil oxalate, medetomidine, and ketamine (TMK; 0.09 +/- 0.02 mg/kg, 0.01 +/- 0.003 mg/kg, and 1.36 +/- 0.33 mg/kg, respectively) with the combination of medetomidine and ketamine (MK; 0.09 +/- 0.02 mg/kg and 3.48 +/- 0.55 mg/kg, respectively) for anesthetization of 17 captive male axis deer (Axis axis) for vasectomy. Nine deer received TMK and eight deer received MK via projectile syringe during the months of January and February, 2005. Mean induction and arousal times, vital signs, and arterial blood gas values were monitored and compared. All animals received supplemental oxygen during the surgical procedure. Animals receiving TMK were reversed with naltrexone (100 mg/mg thiafentanil) and atipamazole (5 mg/mg medetomidine). Animals receiving MK were reversed with atipamazole (5 mg/mg medetomidine). Two MK animals and three TMK animals required supplementation with ketamine i.v. immediately upon handling. Six of the nine animals immobilized with TMK required intubation for positive-pressure ventilation. Two of these six animals also required isoflurane to maintain anesthesia. Mean induction time was 3.5 +/- 2.0 min in the TMK group, and 9.8 +/- 6.7 min in the MK group. Despite shorter mean induction times, animals anesthetized with TMK experienced unpredictable inductions, apnea, muscle rigidity, limb movement, and significant respiratory and metabolic lactic acidosis. MK resulted in smoother inductions, better respiratory function, and less adverse metabolic disturbances, and thus was considered superior to TMK for anesthesia in captive axis deer at the dosages tested.  相似文献   
94.
As part of ongoing ecological studies of Humboldt penguins (Spheniscus humboldti) at Punta San Juan, Ica Department, Peru, health surveys were conducted in November 1992, 1993, and 1994. In the three surveys, 98 birds in total were handled for examination, and blood was collected for laboratory analysis from 90 of these birds. All birds seemed to be in good condition. Body weights of females were significantly lower in 1994 than in the other years. Fleas (Parapsyllus humboldti) and ticks (Ornithodoros amblus) were found on the penguins and in their nests. Females had significantly higher plasma calcium and phosphorus levels, and they had lower weights than males. No other differences were found between the sexes. Hematology, plasma chemistries, and plasma mineral levels varied between years. Positive antibody titers for Chlamydophila psittaci (62%), avian adenovirus (7%; 1994 only), paramyxovirus-2 (7%; 1993 only), and Salmonella Pullorum (7%) were found. Plasma chemistry and mineral levels differed between individuals testing positive vs. negative on serologic tests for avian adenovirus and Salmonella Pullorum. Serologic tests for antibodies to avian influenza A virus, avian encephalomyelitis virus, infectious bronchitis virus, avian reovirus, duck viral enteritis virus, equine encephalitis (eastern, western, and Venezuelan) viruses, infectious bursal disease virus, infectious laryngotracheitis virus, Aspergillus sp., and paramyxovirus-1 and -3 were negative. All chlorinated pesticide and polychlorinated biphenyl analyses were below detectable limits.  相似文献   
95.

Background

Norwegian meadows, including those for silage production, are recently found heavily invaded by the slug Arion vulgaris in exposed areas. As a consequence, large numbers of slugs might contaminate grass silage and cause a possible threat to animal feed quality and safety. It is well known that silage contaminated by mammalian or avian carcasses can lead to severe outbreaks of botulism among livestock. Invertebrates, especially fly-larvae (Diptera), are considered important in the transfer of Clostridium botulinum type C and its toxins among birds in wetlands. C. botulinum form highly resistant spores that could easily be consumed by the slugs during feeding. This study aimed to determine whether Arion vulgaris could hold viable C. botulinum and enrich them, which is essential knowledge for assessing the risk of botulism from slug-contaminated silage. Slug carcasses, slug feces and live slugs were tested by a quantitative real-time PCR (qPCR) method after being fed ≅ 5.8 × 104 CFU C. botulinum type C spores/slug.

Results

Low amounts of C. botulinum were detected by qPCR in six of 21 slug carcasses with an even spread throughout the 17 day long experiment. Declining amounts of C. botulinum were excreted in slug feces up to day four after the inoculated feed was given. C. botulinum was only quantified the first two days in the sampling of live slugs. The viability of C. botulinum was confirmed for all three sample types (slug carcasses, slug feces and live slugs) by visible growth in enrichment media combined with obtaining a higher quantification cycle (Cq) value than from the non-enriched samples.

Conclusions

Neither dead nor live invasive Arion vulgaris slugs were shown to enrich Clostridium botulinum containing the neurotoxin type C gene in this study. Slugs excreted viable C. botulinum in their feces up to day four, but in rapidly decreasing numbers. Arion vulgaris appear not to support enrichment of C. botulinum type C.  相似文献   
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