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161.
Linear-circular hybrid fixators were used to stabilize humeral and femoral fractures in 21 dogs and five cats. Twenty-two of 24 fractures with sufficient follow-up radiographic evaluation obtained union. Time to radiographic union ranged from 25 to 280 days (mean +/- standard deviation [SD] 110+/-69 days; median 98 days). Eleven animals developed minor and two dogs developed major pin and/or wire tract inflammation. Functional outcome was rated as excellent (n=16), good (n=5), and fair (n=3) at the time of final long-term assessment (range 4.5 to 60.0 months; mean +/- SD 28.4+/-15.4 months; median 28.5 months). Follow-up information was unavailable for two animals. Hybrid fixators were useful constructs for stabilization of humeral and femoral fractures, particularly fractures with short, juxta-articular fracture segments.  相似文献   
162.
The aim of this study was to investigate if a 2-step method of preventing suckling and cow-calf separation reduces the stress reaction in foster cows compared with a simultaneous separation method. Seven Swedish Holstein and 5 Swedish Red dairy cows were used as foster cows, each having a group of 4 calves. The foster cow-calf group was formed when calves were 1 wk old, and the calves were prevented from suckling at 10 wk of age. In 6 of the cow-calf groups, calves were prevented from suckling by simultaneous separation from the cow (control). In the other 6 groups, calves were fitted with a nose-flap, which prevented them from suckling while they were kept together with the cow for another 2 wk before they were separated (2-step). The behavior of the foster cows was observed at 4 observation periods, 0 to 2, 8.5 to 9.5, 24 to 26, and 72 to 74 h after the calves were prevented from suckling (2-step), after separation (2-step), and after calves were prevented from suckling by simultaneous separation (control). For both treatments, saliva cortisol was sampled once daily for 5 d at wk 10. This was repeated at wk 12 for the 2-step treatment. Heart rate was measured with the behavioral observations. Control foster cows vocalized more (P < 0.001) and walked more (P = 0.005) than the 2-step foster cows after prevention of suckling and after separation from the calves. When control cows were separated from their calves, they more frequently (P < 0.001) held their head out of the pen than was the case with 2-step cows when separated 2 wk after prevention of suckling. The variation in heart rate was larger in the control group compared with 2-step cows at 0 to 2 h after separation/prevention of suckling (P = 0.002). No effect of treatment was found on cortisol concentration. Our conclusion is that separating the 2 events "prevention of suckling" and "separation" reduces the stress experienced by the foster cow at weaning.  相似文献   
163.
Horses with anhidrosis are defined by signs of impaired thermoregulation caused by sweating that is inadequate for the ambient conditions. Anhidrosis has been recognised since the early twentieth century; affected horses have been variably described as nonsweaters, drycoats, blowers or puffers. The condition affects horses of all age groups, breeds, coat colours, genders and activities and is common among horses in hot, humid environments. Despite the enormous financial and emotional costs of anhidrosis, the causes and pathogenesis of the condition are largely unknown and no consistently effective treatment has been found.  相似文献   
164.
The aim of this study was to determine if algal products rich in DHA or ARA are able to completely replace fish oil in microdiets for marine fish larvae, gilthead seabream and if extra supplementation with EPA may further enhance larval performance. For that purpose, 20 day‐old gilthead seabream larvae of 5.97 ± 0.4 mm mean total length and 0.12 ± 0.001 mg mean dry body weight were fed with five microdiets tested by triplicate: a control diet based on sardine oil; a diet containing AquaGrow® DHA (diet DHA) to completely substitute the sardine oil; a diet containing AquaGrow® ARA (diet ARA); a diet containing both products, AquaGrow® DHA and AquaGrow® ARA to completely substitute the fish oil; and, a diet containing both products, AquaGrow® DHA and AquaGrow® ARA, together with an EPA source. Temperature, air and salinity activity tests were also performed to detect larval resistance to stress. At the end of the experiment, final survivals did not differ among groups. The microorganism produced DHA was able to completely replace fish oil in weaning diets for gilthead seabream without affecting survival, growth or stress resistance, whereas the inclusion of microorganism produced ARA did not improve larval performance. Moreover, addition of EPA to diets with total replacement of fish oil by microorganism produced DHA and ARA, significantly improved growth in terms of body weight and total length. The results of this study denoted the good nutritional value of microorganisms produced DHA as a replacement of fish oil in weaning diets for gilthead seabream, without a complementary addition of ARA. However, dietary supplementation of EPA seems to be necessary to further promote larval performance.  相似文献   
165.
We analysed the effect on production and economic performance of juvenile Litopenaeus vannamei of isoproteic diets substituting fishmeal by 25%, 50%, 75% and 100% with mixtures of wheat, soya bean and cornmeals. In a laboratory trial, 10 juveniles m?2 (1.1 ± 0.1 g) were reared in 60‐L plastic containers using a recirculation system for 90 days. Three replicates were used to test each diet. A commercial diet serving as a reference and the diet with the highest content of essential amino acids (50% substitution, 6.46 ± 1.1 g) produced significantly higher shrimp final weight (7.12 ± 0.9 g, < 0.05). There were not significant differences in specific growth rate and mean survival (85.9 ± 0.2%, > 0.05). In a pond trial, 10 shrimp m?2 (1.08 ± 0.3 g) were cultivated in 1.5 m?3 cages for 35 days, testing the diets in triplicate. Final weight was significantly higher (< 0.05) when 100% substitution was used (10.89 ± 0.24 g), while survival did not differ significantly among diets (> 0.05). The optimal level of substitution was estimated at 86.0%. Apparently, nutrients contained in the diets combined well with natural feed available in the pond, up to a point where 7.3% of fishmeal inclusion is recommended. An economic analysis showed that 100% substitution produced the best results. We conclude that mixtures of wheat, corn and soya meals are potential alternatives to replace fishmeal effectively in diets for L. vannamei.  相似文献   
166.
The objectives of these studies were to assess the diagnostic performance (sensitivity and specificity) of the IgM capture enzyme-linked immunosorbent assay (ELISA; MAC) for diagnosis of West Nile (WN) virus in horses and to examine the performance of this test by using different criteria for seropositivity. A total of 36 horses classified as WN virus infected (group 1) and 383 horses from 4 subpopulations of hoses classified as noninfected (groups 2, 3, 4, and 5) were used in the study. The sensitivity (proportion of infected horses that tested positive for WN virus IgM antibodies) and specificity (proportion of noninfected horses that tested negative) were calculated at different cutoff points by using receiver operating curve (ROC) analysis. Using a selected cutoff point = 2.0, the sensitivity and specificity of the MAC were 91.7 and 99.2%, respectively. The area under the ROC curve = 0.95 (95% confidence interval [CI], 0.89 to 1.0), suggesting that the MAC is a useful tool for diagnosis of recent WN virus exposure in horses. In fulfillment of the 2nd objective, 2 other indices were developed and these indices approached 1.0 for the AUC with smaller 95% CIs. These indices were then used to test 602 additional diagnostic samples submitted from suspect horses between 2002 and 2004. Using the standard cutoff, 194 (32%) of the horses were interpreted as positive. Utilizing newly predicted cutoff criteria from each index, additional horses were identified as positive. In conclusion, the MAC as used for identification of WN virus-diseased horses undergoing recent exposure performs reliably at the standard cutoff for seropositivity. A negative test might not completely rule out WN virus disease, but horses that test negative were most likely not exposed to WNV. Performance of the test can be further improved by investigation of other indexes of seropositivity.  相似文献   
167.
The browning indicators furosine and color were determined in infant cereals and infant cereals containing powdered milk to evaluate the utility of these parameters for monitoring storage. Studies were made on seven infant cereal samples including both gluten and gluten‐free products. Samples were stored under laboratory conditions at 28°C for four or 16 weeks; or under modified water activity conditions at 25°C or 55°C for one, two, three, or four weeks; or under industrial conditions in air or nitrogen atmospheres at 32°C or 55°C for one, three, six, or 12 months. Furosine levels increased during the storage of infant cereals containing powdered milk under all time, temperature, and water activity (aw) conditions assayed, except drastic conditions (55°C, aw = 0.65). Color values increased in infant cereals with gluten (7‐cereal and 8‐cereal samples), regardless of milk content, when they were stored under drastic conditions (55°C or 25°C with normal or modified water activity). However, the gluten‐free infant cereals (rice‐corn and rice‐corn‐soy samples) that have a characteristic yellow color showed no increase in color during storage. The extent of the Maillard reaction was greatest in the infant cereals that included milk in their formulation.  相似文献   
168.
Outbreaks of nosocomial Salmonella infections in hospitalised horses can occur when surveillance and infection control protocols are not in place, or not well structured and enforced. The aim of this article is to present a review of published studies that have contributed to the literature of the epidemiology and infection control aspects of nosocomial Salmonella infections in hospitalised horses. The review highlights important elements that must be taken into consideration during the formulation, implementation and evaluation of a hospital surveillance and infection control programme designed to reduce the risk of an outbreak of nosocomial Salmonella infection in hospitalised horses.  相似文献   
169.
170.
Environmental factors are known to modify the life history of marine ectotherms. In a 16‐month laboratory experiment, we investigated the influence of temperature and presence of predators on life‐history parameters including shell growth, survival and the energy investment in reproduction and body mass of the short‐lived (2–3 years) scallop Argopecten ventricosus. In parallel, A. ventricosus was maintained in the field at the Pacific coast of Baja California, México, to compare growth, survival and reproductive effort under natural conditions. For the laboratory treatments, scallops were reared at simulated field temperatures (SFT), 5 °C above SFT and in the presence of predators. Elevated water temperatures caused higher growth and gonad production, although at the cost of increased mortality. Presence of predators induced energy allocation to muscle rather than gonad growth, deferred spawning and extended survival. Field scallops exhibited higher growth, higher reproductive investment and were able to reproduce twice, whereas all laboratory scallops died after the first spawning. The natural variability of environmental parameters such as food and temperature may thus support optimal growth in the field, and when animals are protected from predators, reproduction in the second year of life.  相似文献   
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