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排序方式: 共有951条查询结果,搜索用时 31 毫秒
41.
J. R. Crabtree 《Equine Veterinary Education》2022,34(3):141-151
Many fillies and mares are accused of behaving badly by their owners or trainers, and their reproductive hormones and ovaries are commonly blamed for this. Overt oestrus behaviour, however natural, is undesirable when a horse is being ridden, trained and competed. More subtle behaviours may be attributed to the reproductive cycle and presented as the cause of poor performance in the elite competition mare. Sometimes behaviours are complex, perhaps at odds with what one expects for normal reproductive behaviour and in many cases may not be associated with the reproductive cycle at all, rather associated with pain of musculoskeletal or soft tissue origin. The situation represents a diagnostic dilemma to positively associate undesirable behaviours with the ovarian hormones or ovarian pain, before an attempt can be made to modify the behaviour through the suppression of oestrus. This article will review the reasons for presentation, the behavioural patterns of the reproductive cycle and the diagnosis of reproductive behavioural problems. The range of techniques for oestrus suppression will be reviewed along with their clinical application and any known current regulatory issues associated with their use. 相似文献
42.
Measuring the productivity and physical workload of brushcutters within the context of a production-based pay system 总被引:1,自引:0,他引:1
Dominic Toupin Luc LeBel Denise Dubeau Daniel Imbeau Luc Bouthillier 《Forest Policy and Economics》2007,9(8):1046-1055
Forestry occupations are known to be physically demanding, and workers are often paid on a piece rate basis. This pay system is largely used in silvicultural treatments such as plantation and vegetation management. An ill adjusted piece rate system may induce workforce recruitment difficulties or increase accident rates and work related illnesses. A study combining work measurement, ergonomics and economics was undertaken to better understand the factors influencing a worker's workload. Mathematical relations between site factors, worker's production and heart rate variation during work have been examined based on time and motion studies of 38 brushsaw operators performing regeneration release (cleaning) in northern forests. Results show that a piece rate pay system that considers only the area treated without taking into account site factors may lead workers to behave in ways that may compromise their health and safety. The use of a pay system that integrates the influence of site factors on work performance is therefore suggested. 相似文献
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44.
《Veterinary immunology and immunopathology》2015,163(1-2):46-56
Our objective was to develop a lipopolysaccharide (LPS) inflammation model in calves to evaluate the acute-phase response with respect to the release of pro-inflammatory cytokines and acute-phase proteins, fever development and sickness behaviour. Fourteen 4-week-old male Holstein Friesian calves were included and randomly assigned to a negative control group (n = 3) and an LPS-challenged group (n = 11). The latter received an intravenous bolus injection of 0.5 μg of LPS/kg body weight. Blood collection and clinical scoring were performed at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 12, 18, 24, 28, 32, 48, 54 and 72 h post LPS administration (p.a.). In the LPS group, the following clinical signs were observed successively: tachypnoea (on average 18 min p.a.), decubitus (29 min p.a.), general depression (1.75 h p.a.), fever (5 h p.a.) and tachycardia (5 h p.a.). Subsequent to the recovery from respiratory distress, general depression was prominent, which deteriorated when fever increased. One animal did not survive LPS administration, whereas the other animals recovered on average within 6.1 h p.a. Moreover, the challenge significantly increased plasma concentrations of tumour necrosis factor-α, interleukin 6, serum amyloid A and haptoglobin, with peaking levels at 1, 3.5, 24 and 18 h p.a., respectively. The present LPS model was practical and reproducible, caused obvious clinical signs related to endotoxemia and a marked change in the studied inflammatory mediators, making it a suitable model to study the immunomodulatory properties of drugs in future research. 相似文献
45.
Investigating the opinions of donkey owners and veterinary surgeons towards pain and analgesia in donkeys
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The aim of this questionnaire‐based study was to identify which analgesics are currently prescribed to donkeys in clinical practice and to collect opinions from veterinary surgeons and donkey owners on the importance of different pain‐related behaviours in donkeys. Questionnaires were completed by 143 veterinary surgeons and 93 donkey owners. Phenylbutazone, flunixin, detomidine and butorphanol were reported as the most frequently used analgesics in donkeys. Most veterinary surgeons reported administering these drugs at the horse dose rate and dosing interval, which may be inappropriate in the donkey. Four pain‐related behaviours were identified as very important by veterinary surgeons and owners: dullness for colic‐associated pain, keeping the foot lifted, and lameness for foot and limb pain and inability to chew properly for head and dental pain. This is a more limited behavioural repertoire than has recently been identified to be associated with pain in the donkey and suggests that the respondents were reporting perceived wisdom as to what people think are the behavioural signs associated with pain or were not interpreting pain‐related behaviours correctly. 相似文献
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47.
基于感知价值的东北黑土区农户保护性耕作技术采用行为 总被引:1,自引:1,他引:0
为破解保护性耕作技术推广困局,本研究基于感知价值理论构建了农户保护性耕作技术采用行为模型,并运用结构方程模型对黑龙江省典型黑土区的733份农户调研数据展开实证研究。结果表明:农户保护性耕作技术采用感知价值是感知利益和感知风险权衡的结果,感知利益和感知风险对感知价值分别有正向和负向影响;感知利益和风险由多个维度构成,各维度感知利益和风险对总体感知利益和风险的影响程度分别为:感知经济利益感知生态利益感知社会利益;感知技术风险感知经济风险感知情境风险;感知利益、感知风险、感知价值与技术采用意愿和行为存在直接和间接的影响关系,感知利益对感知价值和技术采用意愿的影响感知风险对二者的影响,但感知风险对感知行为的影响感知利益对其的影响。鉴于此,从提升农户保护性耕作技术采用利益感知和降低风险感知的角度提出建议,引导东北黑土区农户采用保护性耕作技术。 相似文献
48.
Abstract This study was conducted to evaluate feed discrimination and preference of European sea bass Dicentrarchus labrax L., taking into account the effects of feed location, previous feeding experience and light conditions. Fish (63 g) were held in tanks and exposed to a 12L:12D photoperiod and ambient temperature. The following feeding practices were applied in triplicate: three‐choice feeding (self‐ feeding with feeds formulated for carnivorous, herbivorous and omnivorous fish rotated on a weekly basis) and monofeeding (self‐feeding with one of these feeds). After 9 weeks (phase I), fish previously held in monofeeding, were subjected to three‐choice feeding for 2 weeks (phase II). In phase I, fish discriminated between feeds after their rotational displacements and preferred the feed formulated for carnivorous species. This also supported the best growth. Fish used in phase II preferred the same feed. There was no preference for any location within tanks. Feeding was generally diurnal, although in some tests with the feeds for herbivores and omnivores, diurnal and nocturnal feed demands were similar and fewer in number than with the feed formulated for carnivores. 相似文献
49.
C. de Fourmestraux O. Geffroy B. Siliart O. Albaric C. Tessier 《Equine Veterinary Education》2014,26(1):34-39
The surgical success of laparoscopic castration without orchidectomy results from avascular necrosis of the testes. However, failures and subsequent production of testosterone and stallion‐like behaviour have been previously identified. Laparoscopic castration without removal of the testes was performed in 32 horses with 2 normal descended scrotal testes between July 2006 and October 2012. The objectives of our study were to evaluate the success rate of laparoscopic castration without orchidectomy on descended testes in our population and assess complications and recovery time. Endocrine tests were performed after surgery and owners also asked to report on their horse's behaviour and ability to resume exercise. Castration was deemed successful if endocrine test results were in accordance with gelding values. Failed horses were castrated using a conventional technique and histology performed when possible. Basal testosterone levels decreased below 3 nmol/l after surgery in 30/32 cases. However, in 2 horses, stallion behaviour persisted and histological evaluation after inguinal castration showed residual viable tissue. Two horses maintained high testosterone levels after surgery associated with stallion‐like behaviour. Based on these results, 12.5% of horses (4/32 horses) failed to be considered a gelding based on either endocrine tests and/or histology. All horses, with one exception, were able to resume exercise less than a week after the procedure. Laparoscopic castration without orchidectomy appears to be a safe procedure. When assessing the success of laparoscopic castration, our total failure rate was 12.5% (4/32 horses) which is significantly higher than previously reported. 相似文献
50.
S. Thanner F. Schori R. M. Bruckmaier F. Dohme‐Meier 《Journal of animal physiology and animal nutrition》2014,98(6):1143-1153
The challenge for sustainable organic dairy farming is identification of cows that are well adapted to forage‐based production systems. Therefore, the aim of this study was to compare the grazing behaviour, physical activity and metabolic profile of two different Holstein strains kept in an organic grazing system without concentrate supplementation. Twelve Swiss (HCH; 566 kg body weight (BW) and 12 New Zealand Holstein‐Friesian (HNZ; 530 kg BW) cows in mid‐lactation were kept in a rotational grazing system. After an adaptation period, the milk yield, nutrient intake, physical activity and grazing behaviour were recorded for each cow for 7 days. On three consecutive days, blood was sampled at 07:00, 12:00 and 17:00 h from each cow by jugular vein puncture. Data were analysed using linear mixed models. No differences were found in milk yield, but milk fat (3.69 vs. 4.05%, P = 0.05) and milk protein percentage (2.92 vs. 3.20%, P < 0.01) were lower in HCH than in HNZ cows. Herbage intake did not differ between strains, but organic matter digestibility was greater (P = 0.01) in HCH compared to HNZ cows. The HCH cows spent less (P = 0.04) time ruminating (439 vs. 469 min/day) and had a lower (P = 0.02) number of ruminating boli when compared to the HNZ cows. The time spent eating and physical activity did not differ between strains. Concentrations of IGF‐1 and T3 were lower (P ≤ 0.05) in HCH than HNZ cows. In conclusion, HCH cows were not able to increase dry matter intake in order to express their full genetic potential for milk production when kept in an organic grazing system without concentrate supplementation. On the other hand, HNZ cows seem to compensate for the reduced nutrient availability better than HCH cows but could not use that advantage for increased production efficiency. 相似文献