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991.

Objective

To estimate the prevalence and risk factors for road traffic accidents (RTA) in dogs and describe the management and outcome of these dogs attending primary‐care veterinary practices in the United Kingdom.

Design

Retrospective cross‐sectional study.

Setting

Primary‐care veterinary practices in the United Kingdom.

Animals

The study population included 199,464 dogs attending 115 primary‐care clinics across the United Kingdom.

Measurements and main results

Electronic patient records of dogs attending practices participating in the VetCompass Programme were assessed against selection criteria used to define RTA cases. Cases identified as RTAs were identified and manually verified to calculate prevalence. Univariable and multivariable logistic regression methods were used to evaluate associations between risk factors and RTA. The prevalence of RTA was 0.41%. Of the RTA cases, 615 (74.9%) were purebred, 322 (39.2%) were female, and 285 (54.8%) were insured. The median age at RTA was 2.5 years. After accounting for the effects of other factors, younger dogs had increased odds of an RTA event: dogs aged under 3 years showed 2.9 times the odds and dogs aged between 6–9 years showed 1.8 times the odds of an RTA event compared with dogs aged over 14 years. Males had 1.4 times the odds of an RTA event compared with females. Overall, 22.9% of cases died from a cause associated with RTA. Of dogs with information available, 34.0% underwent diagnostic imaging, 29.4% received intravenous fluid‐therapy, 71.1% received pain relief, 46.0% were hospitalized, and 15.6% had surgery performed under general anesthetic.

Conclusions

This study identified important demographic factors associated with RTA in dogs, notably being young and male.
  相似文献   
992.
The Afrikaner is an indigenous South African breed of “Sanga” type beef cattle along with breeds such as the Drakensberger and Nguni. Six composite breeds have been developed from crosses with the Afrikaner. Additionally, Afrikaner has been the base from which exotic breeds were established in South Africa through backcrossing. The study examined genetic diversity of Afrikaner cattle by genotyping 1257 animals from 27 herds in different geographic areas of South Africa and Namibia using 11 microsatellite markers. Multiple-locus assignment, performed using the Bayesian clustering algorithm of STRUCTURE, revealed three underlying genotypic groups. These groups were not geographically localized. Across herds and markers, the proportion of unbiased heterozygosity ranged from 0.49 to 0.72 averaging 0.57; mean number of alleles per locus ranged from 3.18 to 7.09, averaging 4.81; and allelic richness ranged from 2.35 to 3.38, averaging 2.67. It is concluded that a low inbreeding level of 2.7% and a moderate to high degree of variation still persists within the Afrikaner cattle breed, despite the recent decline in numbers of animals.  相似文献   
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994.
1. Embryos of the domestic fowl (72 h old) have been explanted into shell‐less cultures or ‘surrogate’ eggshells, in order to investigate the possibility of rearing these embryos to hatching.

2. Rocking embryo cultures during the first half of incubation enhanced embryo growth.

3. Embryos explanted into ‘surrogate’ eggshells of either other individuals or other species have been successfully ‘hatched’.

4. A normal chorioallantois is formed in these surrogate eggshells. This enables a functional albumen sac to form and eggshell resorption to be achieved.

5. Embryos grown in ‘surrogate’ eggshells are slightly smaller than controls but otherwise normal.

6. The technique provides opportunities for genetic engineering experiments.  相似文献   

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997.
This study was performed in a 2 × 4 factorial arrangement to explore and compare the effects of inclusion of two live Bacillus additives (B. licheniformis and B. subtilis) at four doses (0, 0.25 × 107, 0.50 × 107 and 0.75 × 107 colony‐forming units (cfu)) on in vitro gas production kinetics, fiber degradation, methane production and ruminal fermentation characteristics of maize stover and rice straw by mixed rumen microorganisms in dairy cows. The pH, concentrations of ammonia nitrogen (NH3‐N) and isovalerate were increased (P < 0.05), while the methane (CH4) production, ratio of acetate to propionate, and total volatile fatty acids (TVFA) concentration were decreased (P < 0.05) by the supplementation of B. licheniformis compared with that of B. subtilis. Adding B. licheniformis and B. subtilis raised (P < 0.05) or numerically raised the maximum gas production, while decreasing (P < 0.05) or numerically lowering pH and concentrations of most volatile fatty acids. The addition of B. licheniformis increased (P < 0.05) the NH3‐N concentration but reduced CH4 production and ratio of acetate to propionate (P < 0.05), while the NH3‐N concentration was decreased (P < 0.05), and the CH4 production and ratio of acetate to propionate were increased by that of B. subtilis compared to the control. Results obtained in this research suggest that B. licheniformis would be preferred as a live Bacillus additive in comparison with B. subtilis, and its optimal dose should be 0.25 × 107 cfu/500 mg substrates.  相似文献   
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鸡肉的健康作用和人类饮食模式   总被引:3,自引:0,他引:3  
随着科学的迅速发展,与食品健康有关的细节问题逐渐暴露出来,业内人士需要获取有用的信息来指导人们选择健康食品.目前,除了母乳,没有任何一种单一食品能够满足人体需要的所有养分.只有综合膳食才能达到此要求,但是要配制一个平衡膳食需要确定不同食物给人体提供的具体养分,这就意味着饮食模式对人类健康和疾病具有一定的影响.从消费者角度看,需要从口味偏好到环境等诸多方面去提倡个人和文化价值.  相似文献   
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