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31.
Objective To investigate the effect of a topical anaesthetic formulation on pain alleviation, wound healing and systemic levels of local anaesthetic actives in lambs undergoing castration and tail docking. Design Three placebo-controlled and/or randomised experiments were conducted using three groups of Merino lambs (n = 62, 68 and 19) undergoing routine castration and tail docking. Procedure Surgical castration, with either surgical or hot-iron tail docking, was performed with and without the application of topical anaesthetic (Tri-Solfen®) or placebo. The effects of this procedure were compared with those of rubber ring castration and tail docking, and of the handled but unmarked controls. Wound pain was assessed using calibrated Von-Frey monofilaments over a 4-h period, pain-related behaviour was assessed over 5 h, wound healing was assessed at 14 and 28 days, and the plasma levels of lignocaine and bupivacaine were determined. Results Rapid and up to 4 h primary hyperalgesia developed following surgical castration and tail docking in the untreated and placebo-treated lambs. It was absent in the castration wounds, and significantly reduced in the tail-docking wounds, of the treated lambs. Hot-iron docking was associated with mild and transient secondary hyperalgesia, which was abolished by the topical anaesthesia. There was a significant reduction in pain-related behaviours in treated lambs, which were not significantly different in their behaviour to the sham-operation handled controls. Plasma lignocaine and bupivacaine levels were below the toxic thresholds in all tested lambs. Conclusion Topical anaesthesia alleviates wound pain and significantly reduces pain-related behaviours in lambs undergoing surgical castration plus surgical or hot-iron tail docking, without a negative effect on wound healing or a risk of systemic toxicity.  相似文献   
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The aim of the present study is to investigate the effects of oral administration of taurine on endogenous glutathione peroxidase (GPx) and Glutathione Reductase (GR) activities and reduced glutathione (GSH) level in normal rats. Normal saline (Group I) or 5% taurine in normal saline was administered in dose of 50 mg (Group II), 250 mg (Group III) or 500 mg kg(-1) of body weight (Group IV) through intragastric intubation for 60 days. GPx and GR enzyme activities and GSH and taurine levels were determined in liver, heart, stomach, kidney and plasma of normal Wistar rats. GPx activity showed an increase in liver, heart, stomach and plasma. GR activity increased in kidney and decreased in liver and plasma. GSH levels increased in liver, stomach and decreased in kidney. Liver showed an increase and heart, stomach and kidney a decrease in taurine level in taurine administered rats when compared to control rats. The results varied from organ to organ and the observed variations among organs might be related to their respective enzymatic, non-enzymatic antioxidant potential and its functions. From the present study it may be concluded that long term oral administration of taurine affects GPx, GR and GSH levels in normal rats.  相似文献   
33.
To date, there is no reported standard mating ratio for Nigerian native chickens despite their large population in the country. This study investigated the effect of mating ratio on behaviour, semen quality and level of stress. Sixty-three (9 cocks and 54 hens) sexually matured birds were randomly assigned to three mating ratios (MR) of 1 cock to 3 hens (1C:3H), 1 cock to 6 hens (1C:6H) and 1 cock to 9 hens (1C:9H), and each MR was replicated three times. Each cock spent 2 weeks in a particular MR before it was moved to another. By the 6th week, all cocks had experienced the three mating ratios. Behaviour of the hens and sexual behaviour of the cocks were observed in the morning and evening, respectively, for 6 weeks. At the end of 2nd week in each MR, semen samples were collected and evaluated for motility, morphology, liveability and concentration, and blood samples were also taken from the cocks to determine the heterophil/lymphocyte (H:L) ratio, an indicator of stress. There was also no significant effect of mating ratio on the fertility of eggs and hatchability of the chicks. The number of hen–hen aggression instances, frequency of visits to the nest box and duration of nesting was not influenced by the mating ratio. However, the duration of nest seeking was higher at 1C:3H and lower at 1C:9H. A mating ratio of 1C:9H is therefore recommended for farmers interested in raising Nigerian native chickens.  相似文献   
34.
Canine hepatozoonosis caused by Hepatozoon americanum has periosteal proliferation on long bones, pelvis, vertebrae, and skull. The pathogenesis of the periosteal proliferation is unknown but may be similar to hypertrophic osteopathy. Objectives were to determine the time frame for onset of bone lesions, to characterize spatial distribution of early bone lesions, and to describe the scintigraphic appearance of bone lesions in six immature dogs infected with 400 H. americanum oocysts on day 0. 99mTc-MDP bone scintigraphy was performed before and after infection. The onset bone lesions noted using scintigraphy was before day 35/36 in three dogs, day 46 in one dog, day 53 in one dog, and between days 46 and 67 in one dog. Early bone lesions primarily occur proximal to the carpus/tarsus and on the axial skeleton. Bone lesions were diffuse, bilaterally symmetric, homogenous, high intensity regions of radiopharmaceutical uptake.  相似文献   
35.
Many causal hypotheses for acute equine abdominal disease (colic) have been proposed. However, few epidemiologic studies have been undertaken to identify risk factors for the syndrome. Risk factors for equine colic were identified using a hospital-based, multi-center, case-control study. Horses admitted with abdominal pain to Cornell, Guelph, Ohio State, Pennsylvania or Tufts university veterinary hospitals between March and December 1991 were selected. Control horses were randomly selected from a list of all other non-colic admissions. The person(s) responsible for the day-to-day care of the horse completed a telephone questionnaire. Risk factors were identified using multivariable logistic regression analysis.

A total of 406 colic and 406 control horses were used in the final analysis. Age, breed, outdoor access (pasture or drylot), outdoor water supply, use of a daily worming product, amount of concentrates and whole-grain corn consumed, type of person responsible for the day-to-day care of the horse and previous colic history were all significantly associated with colic risk. Arabian horses were more than twice as likely to be colic cases (OR = 2.0, 95% CI = 1.0–3.9), whereas Standardbred horses were nearly half as likely (OR = 0.6, 95% CI = 0.4–1.0) to be colic cases compared with the comparison Thoroughbred group. Horses that had access to outdoor enclosures without a continuous supply of water were more than twice as likely (OR = 2.2, 95% CI = 1.2–4.3) to be colic cases compared with horses that had an adequate supply of water on outside enclosures. The use of a daily worming product for at least 60 days during the 12-month period prior to presentation was associated with a significantly lower colic risk (OR = 0.11, 95% CI = 0.02–0.55). Colic risk increased with greater consumption of whole-grain corn; however, when all non-roughage concentrate feeds were combined, colic risk decreased with increased intake of concentrates. Significant interactions were identified between age and drylot use and between the type of care-person responsible for the day-to-day care of the horse (owner or non-owner) and previous colic history.

The findings of this study illustrate the complex multi-factorial nature of equine colic and point towards the importance of the overall quality of stable management and care, as well as the type of outdoor enclosure (pasture or drylot), water access, carbohydrate intake, parasite control and intrinsic (breed-related) factors.  相似文献   

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Radiological skills including ultrasonography and fluoroscopy, require a combination of manual dexterity and visuospatial skill to develop competency. The ability to detect veterinary students with an interest in radiology but who are deficient in these skills, may permit more individual adaptations to training programs, allowing for students training in radiology to achieve maximal potential. The objective of this cohort study was to investigate whether innate dexterity and visuospatial skill could be used to predict performance of basic ultrasound and fluoroscopic skills in veterinary students. Fifty veterinary students from the Ontario Veterinary College completed three tests of visuospatial ability, two tests of manual dexterity, a three‐dimensional mouse task, an ultrasound skill‐testing task, and a fluoroscopic skill‐testing task. Students who reported chopstick use completed the non‐dominant hand ultrasound task significantly faster than students who did not (P = 0.001). There was a significant positive association between scores on the Mental Rotations Test and time to complete the non‐dominant hand ultrasound task (P = 0.011) and fluoroscopy task (P = 0.029). No variables were associated with time to complete the dominant hand ultrasound task. The results of this study suggest that visuospatial skill, as assessed by the Mental Rotations Test, is a better predictor of baseline ultrasound and endovascular fluoroscopy skill than dexterity, with the exception of reported chopstick use, in veterinary students. Visuospatial skills can be developed and may be useful to include in the veterinary curriculum for students that are deficient, or students entering a field such as diagnostic imaging.  相似文献   
39.
The results of a field trial conducted at the Livestock Research Station, Thiruvazhamkunnu, Kerala to study the compatibility of different components in a silvo-pastoral system revealed that growth and yield of fodder species were significantly influenced by the tree components only after tree canopy formation. The fodder species such as Pennisetum purpureum Schum., Panicum maximum Jacq., Brachiaria ruziziensis Griseb. and Euchlaena mexicana Schrad. grown in association with Casuarina equisetifolia J. R. & G. Forst. and Ailanthus malabarica DC recorded comparatively higher forage yield even after canopy formation. However, forage crops grown in combination with Acacia auriculiformis A. Cunn. ex Benth. and Leucaena leucocephala (Lam.) de Wit. registered relatively lower values for growth and yield. Increased light infiltration into the understorey due to the cladophyllous canopy can be attributed as reason for the higher fodder productivity under Casuarina. Due to the combination of crown size and shape, tree height and spacing the amount of light intercepted by Ailanthus also was very low. Among the four multi-purpose trees used, Acacia recorded the maximum growth rate followed by Casuarina, Ailanthus and Leucaena. Forage productivity of the four species was in the order: Pennisetum purpureum > Panicum maximum > Brachiaria ruziziensis > Euchlaena mexicana. Casuarina with Pennisetum/ Panicm were found to be optimal tree — forage combinations for silvo-pastoral systems.  相似文献   
40.
Abstract

Two wood plastic composite (WPC) boards, one experimental and one commercial, were exposed to exterior conditions and evaluated non-destructively using a clinical magnetic resonance imaging (MRI) unit for moisture content (MC) and distribution. The experimental board was exposed in Vancouver, British Columbia, for more than 8 years, and the commercial board was exposed near Hilo, Hawaii, for 2 years. Both boards were characterized in terms of wood content, density, water uptake properties and voids content. The experimental board was additionally destructively analysed for water absorption of the WPC and MC calculated based on the wood content for verification of MRI results. MRI detected the presence of free water and its distribution in both of the WPC boards. Fibre saturation in the experimental board was found to be about 22–24%, in comparison to 25–30% present in most wood species. There was good correlation between the detection of free water by MRI and by destructive testing. Magnetic resonance images showed various major points of water entry in the WPC boards such as the support area, the cut ends, the dripping edge and the sides of the boards. For the experimental board, significant water entry also occurred at the upper exposed surface.  相似文献   
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