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991.
Poxvirus infections are common in domestic birds in Germany, but they are rare in birds of prey. Only species of falconidae imported from Arabian or Asian countries have so far tested positive for poxvirus, and, among these, only raptors kept for falconry. As part of a reintroduction programme in the northern county of Mecklenburg-Western Pomerania, which is adjacent to the Baltic Sea, 21 young peregrine falcons were released into the wild; six of them died and one was examined postmortem, its tissues being examined by light and electron microscopy. In addition, an ELISA for fowlpox, pigeonpox and canarypox was applied. No virus could be isolated and propagation in culture failed, but virus particles were detected by electron microscopy in lesions from its skin and tongue.  相似文献   
992.
Young adult heterozygous (carrier) female dogs with X-linked hereditary nephropathy (XLHN) have glomerular proteinuria but are otherwise healthy. Because data regarding dietary influences on the magnitude of proteinuria in dogs with spontaneous glomerular disease are not available, 12 such dogs were studied in a double crossover experiment intended to determine effects of altering dietary protein intake for up to 6 weeks. Dogs were blocked by urine protein : creatinine ratio (UPC) and randomly assigned to receive 2 diets: high protein (34.6% dry matter [DM], HP) or low protein (14.1% DM, LP) fed in HP-LP-HP or LP-HP-LP sequence. Food intake was measured daily, body weight (BW) was measured twice weekly, and UPC, plasma creatinine, blood urea nitrogen, phosphorus, albumin, and protein concentrations were measured at 2-week intervals. Nutrient digestibility was measured during the third treatment period. Diet had a significant effect (P < .0001) on all measured variables except plasma phosphorus (P > .5), but unintended differences in digestibility of protein and energy (P < or = .01) prevented assignment of the diet effect exclusively to protein. Proteinuria was greater (UPC 4.7 +/- 2.2 versus 1.8 +/- 1.1, P < .0001) when the HP diet was fed, but the LP diet did not maintain starting BW or plasma albumin concentration within the normal reference range. Diet greatly affects the magnitude of proteinuria in XLHN carrier females. Dietary protein restriction can reduce proteinuria in dogs with glomerular disease, but BW and blood protein concentrations may not be maintained if the restriction is too severe.  相似文献   
993.
Effects of spray-dried animal plasma (SDAP) on intake and apparent digestibility of major dietary components were determined using 22 adult Beagles. Trials 1 and 2 used six and eight dogs, respectively, in a switchback design using 10-d periods. Trial 3 used eight dogs in a replicated 4 x 4 Latin square design with 15-d periods. The final 5 d of each period were used for measurement of intake and fecal collections. In Trial 1, dry extruded dog food kibbles were coated with 5% tallow, 2% commercial flavor, and 0 or 2% SDAP (as-fed basis). In Trial 2, commercially available dry dog food, previously coated with fat and flavor were coated with 0 or 2% SDAP. In Trial 3, SDAP (0, 1, 2, or 3%) was blended with other ingredients and extruded (as-fed basis). Kibbles were subsequently coated with 5% poultry fat and 1% commercial flavor. Intake, fecal consistency, and apparent digestibility of nutrients were determined. Addition of SDAP did not markedly affect chemical composition of diets and did not affect intake. Digestibility of DM was improved (P < 0.04) an average of 3.2% when 2% SDAP was included in the diet for all trials. Organic matter digestibility was improved (P < 0.01) in Trials 2 and 3 by an average of 2.9%. Also, digestibility of crude fiber (Trials 1 and 2) or total dietary fiber (Trial 3) was increased with addition of SDAP to the diet (P < 0.01). Fecal DM excretion was decreased by an average of 15% across all trials with the addition of SDAP. Spray-dried animal plasma was an acceptable ingredient in dry dog food preparations, resulting in improved digestion and decreased fecal output. Changes in digestion that occurred with addition of SDAP suggested alteration in digestive capacity in dogs.  相似文献   
994.
REASONS FOR PERFORMING STUDY: Although the efficacy of dexamethasone for the treatment of recurrent airway obstruction (RAO) has been documented, the speed of onset of effect and duration of action are unknown, as is the efficacy of orally administered dexamethasone with or without fasting. OBJECTIVES: To document the time of onset of effect and duration of action of a dexamethasone solution i.v. or orally with and without fasting. METHODS: Protocol 1 used 8 RAO-affected horses with airway obstruction in a crossover design experiment that compared the effect of i.v. saline and dexamethasone (0.1 mg/kg bwt) on pulmonary function over 4 h. Protocol 2 used 6 similar horses to compare, in a crossover design, the effects of dexamethasone i.v. (0.1 mg/kg bwt), dexamethasone per os (0.164 mg/kg bwt) with and without prior fasting, and dexamethasone per os (0.082 mg/kg) with fasting. RESULTS: Dexamethasone i.v. caused significant improvement in lung function within 2 h with a peak effect at 4-6 h. Dexamethasone per os was effective within 6 h with peak effect at 24 h at a dose of 0.164 mg/kg bwt prior to feeding. The duration of effect was, for all dexamethasone treatments, statistically significant for 30 h when compared to saline and tended to have a longer duration of effect when used orally. Dexamethasone per os at a dose of 0.164 mg/kg bwt to fed horses had mean effects comparable to dexamethasone at a dose of 0.082 mg/kg bwt per os given to fasted horses, indicating that feeding decreases bioavailability. CONCLUSIONS: Dexamethasone administered i.v. has a rapid onset of action in RAO-affected horses. Oral administration of a bioequivalent dose of the same solution to fasted horses is as effective as i.v. administration and tends to have longer duration of action. Fasting horses before oral administration of dexamethasone improves the efficacy of treatment. POTENTIAL RELEVANCE: Oral administration to fasted horses of a dexamethasone solution intended for i.v. use provides an effective treatment for RAO-affected animals.  相似文献   
995.
Two genotypes of bovine viral diarrhoea virus (BVDV) are recognised. Type 2 was first recognised when virulent strains caused significant losses among cattle in North America. Subsequently, BVDV type 2 has been found in many other countries, but recent studies have shown that only type 1 BVDV is circulating in the UK herds (sheep and cattle) with type 1a predominating. During routine genotyping of UK BVDV isolates, a type 2 isolate was identified. Phylogenetic analysis of the 5'-untranslated region of the viral genome showed it to be a BVDV type 2a, most similar to a low virulent US strain of BVDV type 2. Antigenic typing with a panel of monoclonal antibodies verified this classification. This is the first confirmed isolation of BVDV type 2 found circulating in the UK.  相似文献   
996.
Epidemiology of microsporidiosis: sources and modes of transmission   总被引:8,自引:0,他引:8  
Microsporidia are single-celled, obligate intracellular parasites that were recently reclassified from protozoa to fungi. Microsporidia are considered a cause of emerging and opportunistic infections in humans, and species infecting humans also infect a wide range of animals, raising the concern for zoonotic transmission. Persistent or self-limiting diarrhea are the most common symptoms associated with microsporidiosis in immune-deficient or immune-competent individuals, respectively. Microsporidian spores appear to be relatively resistant under environmental conditions, and species of microsporidia infecting humans and animals have been identified in water sources, raising concern about water-borne transmission. Sensitive and specific immunomagnetic bead separation and PCR-based methods are being developed and applied for detecting microsporidia in infected hosts and water sources for generating more reliable prevalence data. The most effective drugs for treating microsporidiosis in humans currently include albendazole, which is effective against the Encephalitozoon species but not against Enterocytozoon bieneusi, and fumagillin, which has broader anti-microsporidia activity but is toxic in mammals, suggesting a need to identify better drugs. Strategies to capture and disinfect microsporidia in water are being developed and include filtration, coagulation, chlorination, gamma-irradiation, and ozonation.  相似文献   
997.
998.
AIM: To determine the welfare of calves arriving at a slaughter plant by assessing their physical state and plasma biochemical profile. METHODS: Calves (n=7,169) aged 4-10 days, were examined immediately after they were unloaded from trucks (n=20) and categorised on physical grounds as being in an 'unacceptable', 'marginal' or 'acceptable' state. 'Unacceptable' calves were lying down, unable to walk, extremely weak or seriously injured. 'Marginal' calves had a wet umbilicus, were hollow sided, apparently immature, or weak and slow and unsteady on their feet. 'Acceptable' calves were strong, walked freely, round-sided, bright and alert and had a dry umbilicus. After unloading, 27 'unacceptable', 306 'marginal' and 289 'acceptable' calves were weighed, examined clinically and a blood sample was taken from each. A second blood sample was taken from 118 of these calves, 12-15 hours later. The packed cell volume (PCV) and plasma concentrations of glucose, beta-hydroxybutyrate (BHB), total plasma proteins (TPP), gamma-glutamyl transferase (GGT), urea, creatine kinase (CK) and lactate were measured. RESULTS: Only 27 of the 7,169 calves examined (0.4%) were categorised as being in an 'unacceptable' state on arrival and these were euthanased shortly after unloading. Generally, the plasma biochemical profiles of the 'acceptable' calves were similar to those of 'marginal' animals. However the glucose concentration of 'marginal' calves was lower than that of 'acceptable' calves, suggesting that they had lower energy reserves. After 12-15 h in lairage, plasma glucose concentration decreased and the BHB concentration increased in both 'acceptable' and 'marginal' calves compared with concentrations measured on arrival. CONCLUSIONS: The percentage of calves presented for slaughter in an 'unacceptable' state was small (0.4%). However, 4% of calves were classified as 'marginal' and failed to meet all the requirements of the code of recommendations and minimum standards governing the welfare of young calves in New Zealand. The categorisation of calves by a physical assessment was supported by results of plasma biochemistry. As a result, plasma biochemical profiles are considered unnecessary for making decisions regarding the welfare status of calves arriving at a slaughter plant; an assessment of their physical state is sufficient.  相似文献   
999.
Two 2 x 2 factorial arrangement trials were conducted to evaluate the effectiveness of fat supplementation in improving the energy value of diets containing a high level of a fibrous feedstuff (oats) for growing-finishing swine. Corn-soybean meal-based diets were used that contained either 0 or 40% ground oats and either 0 or 3% added fat. Each trial used 120 pigs (27 kg) with each treatment assigned to five pens of six pigs each. Growing diets (.80% lysine for basal diet) were given from 27 to 55 kg live weight and finishing diets (.64% lysine) from 55 to 102 kg. Diets were formulated to a constant calculated ME to lysine ratio within the growing and finishing phases. Apparent digestibilities of DM and energy were determined for the growing and finishing diets by the indigestible marker (chromic oxide) method. The inclusion of oats in the diets resulted in poorer (P less than .01) feed conversion efficiency and reduced (P less than .01) apparent DM and energy digestibilities. The addition of fat improved (P less than .01) feed conversion efficiency but had no effect (P greater than .10) on DM or energy digestibility. The improvements noted for feed conversion efficiency were similar (P greater than .10) regardless of the dietary oat content. The 3% dietary fat supplementation was equally effective in improving feed conversion efficiency whether the diets did contain or did not contain ground oats for growing-finishing swine.  相似文献   
1000.
Chrysomya megacephala, also known as the Oriental latrine fly, is indigenous to south-east Asia. During the 1970's it successfully invaded Africa and South America, and more recently during the 1980's also established itself in the United States of America. Although the first specimens from South Africa were collected from the south-western Cape Province in 1978, no published data appears to exist on its subsequent spread or status in southern Africa. During May 1991 a specimen of C. megacephala was incidentally captured near Beaufort West, Cape Province, South Africa, which prompted re-examination of blow-flies captured in the Kruger National Park during 1984. In this way it was found that C. megacephala was already well established in the south-eastern Transvaal by mid-1984. Adult C. megacephala can easily be confused with C. bezziana and medical/veterinary entomologists and veterinarians should take note of the existence of this species and the fact that it is probably widespread throughout southern Africa at this state.  相似文献   
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