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101.
Tropical Animal Health and Production - Imprudent administration of antimicrobial drugs in food-producing animals can facilitate the development and spread of antimicrobial-resistant organisms and...  相似文献   
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OBJECTIVE: To report our experience and complications associated with different cannula insertion techniques for laparoscopy in standing horses. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Forty horses that had laparoscopy for diagnostic or surgical purposes. METHODS: After a physical examination, including rectal palpation, standing laparoscopy was performed in 40 sedated horses. Local anesthetic was injected at each site of cannula insertion in the left flank. Horses were divided into 5 groups: Pneumoperitoneum was induced before cannula insertion using a Verres needle (group 1, n = 3) or a 12-g catheter (group 2, n = 14); the cannula was inserted before inducing a pneumoperitoneum (group 3, n = 9); the cannula was inserted under visual control, using an operating laparoscope (group 4, n = 2) or a Visiport Optical Trocar (group 5, n = 12). Horses were observed for 7 days. RESULTS: Problems with insufflation or cannula insertion occurred in 12 horses: 6 had peritoneal detachment, 4 had a splenic puncture, and 2 had descending colon puncture. Eleven of these complications occurred in groups 1 to 3 and only 1 in groups 4 and 5. CONCLUSIONS: The Visiport optical device allows controlled insertion of the initial trocar, and thus avoided potential problems associated with "blind" cannula insertion techniques and was used effectively in horses that had feed withheld for 12 hours. This technique enables direct insertion of a cannula directly into the right flank. CLINICAL RELEVANCE: Complications associated with initial cannula insertion in the paralumbar fossa, for laparoscopy, in standing horses can be minimized with the use of an optical cannula.  相似文献   
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The metabolic fecal nitrogen and digestibility estimates in the grasscutter were determined using 12 captive-bred adult animals fed with four experimental diets differing primarily in crude protein content using nitrogen balance trial approach. Grasscutters required 343.5 mg N kg-0.75 d-1 of nitrogen to meet maintenance requirements, which were met on diets containing 7.4% crude protein. The true digestibility of nitrogen was moderate (52%) but within the range for eutherians. Dry matter intake increased with decreasing dietary nitrogen content, suggesting that animals on nitrogen-deficient diets displayed appreciable compensatory intake. Metabolic fecal nitrogen was 3.5 g N kg-1 dry matter intake, and endogenous urinary nitrogen was 257.5 mg N kg-0.75 d-1. The low value of metabolic fecal nitrogen found for grasscutters affected the dry matter intake required for nitrogen balance, and it may allow grasscutters to exploit nitrogen poor diets.  相似文献   
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The efficacy of Solanum incanum and Strychnos spinosa aqueous fruit extracts was evaluated against cattle ticks in on-station experiments and laboratory tick bioassays. In the on-station experiment using cattle, fruit extracts were applied at three concentrations 5, 10, and 20 % (w/v) and compared with a commercial acaricide, Tickbuster® (amitraz) spray (positive control) and no treatment (negative control). The treatments were applied at weekly intervals for 6 weeks as surface sprays on 32 Mashona cattle in a completely randomized design experiment. Ticks on individual cattle were identified, counted, and recorded daily. Peripheral blood samples were collected for parasite screening. In the laboratory, tick bioassays were conducted at four concentrations, 5, 10, 20, and 40 % (w/v) fruit extracts compared to Tickbuster® (amitraz) spray (positive control) and distilled water (negative control). The extracts were incubated with Rhipicephalus (Boophilus) decoloratus tick larvae and mortalities for each treatment level recorded after 24 and 48 h. The 5 % Solanum incanum treatment had higher efficacy ratio (P?<?0.05) than the other fruit extract concentrations of the same plant species. Efficacy ratio was higher (P?<?0.05) in the 5 % S. spinosa-treated cattle than in the untreated control but lower (P?<?0.05) than that for the amitraz treatment. The bioassays indicated that there was a high efficacy ratio for the lowest fruit extract concentrations when ticks were exposed to acaricidal treatments for 48 h compared to 24 h. Overall, the results indicate that Solanum incanum and Strychnos spinosa individually have some acaricidal effect.  相似文献   
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Since 2006, the members of the molecular epidemiological working group of the European "EPIZONE" network of excellence have been generating sequence data on avian influenza and avian paramyxoviruses from both European and African sources in an attempt to more fully understand the circulation and impact of these viruses. This review presents a timely update on the epidemiological situation of these viruses based on sequence data generated during the lifetime of this project in addition to data produced by other groups during the same period. Based on this information and putting it all into a European context, recommendations for continued surveillance of these important viruses within Europe are presented.  相似文献   
107.
A cross-sectional study was conducted between May 2003 and January 2004 on 130 households and 655 (246 indigenous and 409 crossbred) cattle to determine the prevalence of bovine tuberculosis (bTB) and assess risk factors associated with prevalence in smallholder dairy and traditionally managed herds in the Tanga region of North-eastern Tanzania. Random sampling, single intradermal tuberculin (SIT), comparative intradermal tuberculin (SCIT) tests and a questionnaire were used to gather individual animal and herd level information. From 642 animal tested by SIT, 35 (5.4%) were positive reactors for tuberculosis. Out of those 35 bTB positive reactors, eight (1.25%) proved to be positive reactors for tuberculosis upon further testing by SCIT. Based on the SCIT test, individual animal prevalences of bTB in the smallholder dairy and traditionally managed cattle was 2% and 0%, respectively. The corresponding overall herd prevalence was 5.7% and 0%, respectively. In conclusion, bTB prevalence seems low; however, its potential risk to public health is of concern; underscoring the need for further research, active surveillance to better understand the epidemiology of the disease in different cattle production systems in Tanzania.  相似文献   
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Endogenous uric acid and urea metabolism in the chicken   总被引:1,自引:0,他引:1  
1. Four chickens were used in nine successive experiments using a single injection radioisotope dilution technique to study the kinetics of endogenous uric acid and urea metabolism. 2. Starvation lowered uric acid and urea entry rates, but elevated the extent of degradation of these compounds. 3. Urea turnover time and the extent of urea pool degradation were higher, and urea excretion rate was lower than that of uric acid. 4. In colostomised chickens, the extent of uric acid and urea degradation were lower than in non-colostomised birds. 5. The average uric acid and urea entry rates in chickens fed on a diet containing 200 g protein/kg were 7.32 and 2.6 mumol/h g liver, respectively. 6. It is concluded that the contribution of uric acid and urea to the nitrogen economy of the birds is negligible.  相似文献   
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