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The concept of coping can be used to relate the environmental conditions provided for livestock to their responses--their productivity and their welfare. Pigs are "ecological generalists" and hence are "designed" to cope with a wide variety of environmental conditions. They, however, show clear limits to their adaptability both in terms of the space they require and the pen materials they can endure without injury. Even where they adapt to a wide range of conditions, there often is a particular environment that gives optimum performance. Examples of temperature requirements and feeding facilities are discussed. The process of coping is shown to impose a biological "cost" in some instances and, although a pig has adapted to a specific environment, questions still remain concerning whether keeping a pig in that environment is justifiable.  相似文献   
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Objectives

(1) To collect the perceptions of veterinarians performing equine castrations in Australia on techniques, preferences and outcomes, (2) to investigate veterinarian use and experience with the Henderson castrating instrument and (3) to investigate potential associations between demographics, castration methods and techniques, and complications.

Design

Online survey of members of the Australian Veterinary Association’s Special Interest Group, Equine Veterinarians Australia (EVA).

Methods

A link to the survey was included in the EVA e‐newsletter and practices on the EVA website were contacted by telephone and follow‐up email. Fisher’s exact test was used to determine associations between ligation and complications. A generalised linear model with a negative binomial family was used to determine associations between count response variables and categorical independent variables.

Results

Responses were obtained from 138 veterinarians (response rate, 13.1%) who performed 5330 castrations over 12 months. Castrations were most commonly performed in the field, on anaesthetised horses, using emasculators, via an open approach and without ligation of the spermatic cord. Estimated complications after use of emasculators were swelling (25%), haemorrhage (5%) and infection (5%). The Henderson instrument was used by approximately 10% of respondents and its use for castration was associated with fewer reports of postoperative swelling compared with emasculators (P = 0.002). Rates of evisceration with the Henderson and emasculator methods were comparable (0.43% and 0.9%, respectively).

Conclusion

Castration preferences varied widely among survey participants. Reported complication types and rates were comparable to those reported previously in other countries. Perceptions that the Henderson instrument was associated with less swelling should be investigated further via a prospective controlled investigation.  相似文献   
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The purpose of this article is to provide a review of the current knowledge and opinions about the epidemiology, clinical findings (including sequelae), diagnosis, treatment and monitoring of equine pituitary pars intermedia dysfunction, particularly in the Australian context. This information and the recommendations provided will assist practitioners in making informed decisions regarding the diagnosis and management of this disorder.  相似文献   
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The veterinary profession is experiencing a shortage of veterinarians, with attrition recognised as a substantial contributor. Research has also indicated increased levels of mental ill health and alarming suicide rates in practitioners. The primary aim of this study was to investigate the impact of eleven modifiable workplace factors on mental health outcomes, job appreciation and intention to leave the veterinary profession. The second aim was to ascertain whether workplace factors influence mental health outcomes after controlling for individual resilience. An online survey was completed by 73 practising Australian veterinarians. Unfavourable workplace factors correlated with adverse outcomes including depression, stress, reduced job appreciation and increased likelihood of leaving both the role and the profession. Workplace factors remained linked with the outcomes of job appreciation, depression and stress whilst controlling for practitioner resilience. Job appreciation was a significant predictor of intention to leave both the current role and the profession. Via multiple linear regression, two categories were identified as associated with improved psychological outcomes and job appreciation. These were workplace factors that represent breaks from workload and control or decision latitude in the workplace. Whilst resilience represents a key area for intervention, workplace factors potentially represent an easier-to-modify area for intervention.  相似文献   
6.
Transferring ecological information across scale often involves spatial aggregation, which alters information content and may bias estimates if the scaling process is nonlinear. Here, a potential solution, the preservation of the information content of fine-scale measurements, is highlighted using modeled net ecosystem exchange (NEE) of an Arctic tundra landscape as an example. The variance of aggregated normalized difference vegetation index (NDVI), measured from an airborne platform, decreased linearly with log(scale), resulting in a linear relationship between log(scale) and the scale-wise modeled NEE estimate. Preserving three units of information, the mean, variance and skewness of fine-scale NDVI observations, resulted in upscaled NEE estimates that deviated less than 4% from the fine-scale estimate. Preserving only the mean and variance resulted in nearly 23% NEE bias, and preserving only the mean resulted in larger error and a change in sign from CO2 sink to source. Compressing NDVI maps by 70–75% using wavelet thresholding with the Haar and Coiflet basis functions resulted in 13% NEE bias across the study domain. Applying unique scale-dependent transfer functions between NDVI and leaf area index (LAI) decreased, but did not remove, bias in modeled flux in a smaller expanse using handheld NDVI observations. Quantifying the parameters of statistical distributions to preserve ecological information reduces bias when upscaling and makes possible spatial data assimilation to further reduce errors in estimates of ecological processes across scale.  相似文献   
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Three experiments were conducted to evaluate P bioavailability, growth performance, and nutrient balance in pigs fed high available P (HAP) corn with or without phytase. The bioavailability of P in normal and HAP corn relative to monosodiumphosphate (MSP) for pigs was assessed in Exp. 1. In a randomized complete block design, 96 pigs (average initial BW 9.75 kg) were fed eight diets for 28 d. The reference and test diets were formulated by adding P as MSP, HAP, or normal corn at 0, 0.75, or 1.5 g/kg to a corn-starch-soybean meal basal diet (2.5 g/kg P) at the expense of cornstarch. Plasma inorganic P concentration responded linearly (P < 0.05) to supplemental P intake. Estimates of P bioavailability from HAP andnormal corn when plasma P was regressed on supplemental P intake were 46 and 33%, respectively. In Exp. 2 and 3, pigs were fed corn-soybean meal-based diets containing HAP corn or normal corn and 0 or 600 units of phytase per kilogram in a 2 x 2 factorial arrangement (two corn sources and two levels of phytase). In Exp. 2, 48 crossbred pigs (barrow:gilt, 1:1) averaging 9.25 kg were used to evaluate growth performance. There were no detectable interactions between corn source and phytase for any of the performance criteria measured. Pigs receiving normal corn had the lowest (P < 0.05) BW and rate of gain. Feed efficiency was lower (P < 0.05) in pigs fed normal compared with those fed the HAP corn phytase-supplemented diet. In Exp. 3, 24 crossbred barrows averaging 14.0 kg were used to evaluate nutrient digestibility. There were no detectable interactions between corn and phytase for any of the N and Ca balance criteria. Nitrogen and Ca retention were improved in pigs receiving HAP corn with phytase (P < 0.05). Retention and digestibility of P was lowest (P < 0.01) for pigs on normal corn diet without phytase. The percentage of P digested and retained was improved and fecal P excretion lowered (P < 0.05) by feeding HAP corn.The results of this study indicate that the bioavailability and balance of P in HAP corn is superior to that of normal corn. The addition of 600 phytase units (Natuphos 600, BASF) to HAP corn-based diets further improved P digestibility and reduced P excretion in pigs.  相似文献   
10.
OBJECTIVE: To assess the long-term clinical outcome of horses with distal tarsal osteoarthritis (OA) in which a 3-drill-tract technique was used to induce arthrodesis of the affected joints, identify any preoperative or operative factors associated with outcome, and describe any complications associated with the technique. DESIGN: Retrospective study. ANIMALS: 54 horses. PROCEDURE: Medical records were reviewed for information on signalment, use, history, physical and lameness examination findings, surgical technique, and postoperative care. Radiographs were examined, and severity of OA was graded. Follow-up information was obtained through telephone interviews with owners at least 13 months after the procedure. RESULTS: 32 (59%) horses had a successful outcome, 6 (11%) improved but were not sound after surgery, and 16 (30%) did not improve following surgery. Outcome was negatively associated with the previous use of intra-articular injections. Few postoperative complications were evident. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that distal tarsal OA in horses can be successfully treated by means of distal tarsal arthrodesis with a 3-drill-tract technique. Horses with advanced distal tarsal OA are likely to have poorer outcomes, and the procedure will likely be of minimal benefit in horses with concomitant causes of hind limb lameness prior to surgery and in horses with preexisting proximal intertarsal joint disease.  相似文献   
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