Footrot and lameness in sheep

Since November 2002, the State Veterinary Service and the Veterinary Laboratories Agency have been conducting a field trial to assess the interferon-gamma test as an ancillary parallel test to the tuberculin skin test in herds with confirmed tuberculosis breakdowns. Here, Martin Vordermeier, Tony Goodchild, Richard Clifton-Hadley and Ricardo de la Rua describe the background to the trial, discuss the principle of the test and provide an update of progress so far     

Footrot and interdigital dermatitis in sheep: farmers' practices, opinions and attitudes

In 1999, a study was initiated to improve the treatment and control of footrot and interdigital dermatitis in sheep flocks in England and Wales. In November 2000, a retrospective cross-sectional study was conducted in which 392 sheep farmers were asked to estimate the prevalence of footrot and interdigital dermatitis in their flock in the previous 12 months, whether they considered these diseases to be a problem, how they treated and controlled them and their opinion on the success of the treatment and control measures that they used; 209 of them provided usable responses. The farmers tended to be more concerned as the prevalence of the diseases increased; 91 per cent of the farmers with a prevalence of footrot of less than 5 per cent considered it a small or very small problem on their farm, but 51 per cent of the farmers with a prevalence of 5 per cent or more also considered it to be a small or very small problem. Approximately 60 per cent of the farmers who used parenteral antibiotics considered that they were good or excellent at treating footrot, and this treatment was associated with a prevalence of less than 5 per cent. A similar proportion of farmers also considered topical foot sprays and footbathing to be good or excellent for controlling footrot or interdigital dermatitis, but these treatments were not associated with a lower prevalence of footrot or interdigital dermatitis. Of the 29 farmers who used a footrot vaccine, 20 (69 per cent) considered it good to excellent and this was associated with a prevalence of footrot of less than 5 per cent in their flock; however, vaccination was not associated with lower levels of footrot across the whole sample. Farmers spent approximately 34 minutes per sheep per year treating and controlling footrot; 31 per cent were prepared to spend more money and more time to manage footrot, 27 per cent were prepared to spend more time, 19 per cent were prepared to spend more money and 23 per cent were not prepared to do either. The farmers who were willing to invest more money or more money and time had a higher prevalence of footrot.     

奶牛腐蹄病诊断方法研究进展

奶牛腐蹄病是在世界范围内发生的一种奶牛常见病,严重影响奶牛的生产性能,给奶牛养殖业造成巨大的经济损失。坏死杆菌是奶牛腐蹄病的主要病原菌,近年来得到了广泛而深入的研究。作者在本实验室研究成果基础上,对奶牛腐蹄病坏死杆菌的病原诊断研究进展作一综述,望为奶牛腐蹄病的早期诊断和及时治疗提供参考。     

我国奶牛腐蹄病防治研究进展

奶牛腐蹄病是影响我国奶业发展的重要疾病,常给奶业造成巨大的经济损失,严重制约了奶业的健康快速发展。文章从我国奶牛腐蹄病的流行病学、诊断、预防和治疗几个方面进行了综述。     

果洛地区藏系绵羊腐蹄病病因与综合防制

2002年初~2006年6月对果洛地区患有腐蹄病的2670只藏系绵羊经过调查，发现主要是由坏死杆菌、螺旋体等病原菌感染引起，饲草、气候变化、放牧方式、环境卫生也对蹄病影响较大。经过注射普鲁卡因青霉素、复合VB、硫酸铜等药物和采取相对科学的防制措施后，除发病严重的801只死亡外，其余绵羊痊愈，治愈率达到70%。     

羊腐蹄病诊断及防治方法研究进展

腐蹄病又称蹄间腐烂或趾间腐烂,是一类引起反刍动物蹄部感染的传染病,以跛行、指(趾)间皮肤肿胀和炎症为主要特征。随着集约化养殖业的快速发展,羊腐蹄病发病率日益增加,给养羊业带来巨大的经济损失,严重制约着养羊业的健康快速发展。但到目前为止,国内学者对羊腐蹄病的诊断与防治方面总结性的报道较少。因此,根据实际情况制定出快速诊断和防治方法显得非常重要。论文以近年来国内外最新的研究资料为基础,从羊腐蹄病病原、临床症状、诊断和防治方法等方面进行综述,以期为羊腐蹄病诊断和防治提供参考。     

不同途径补锌防治牛羊腐蹄病的情况概述

腐蹄病是牛、羊等反刍动物的常见蹄病,兽医临床上通常采用修蹄、浴蹄和药物抗菌等措施防治.锌是目前确认必需的15种微量元素中生理功能最多的一种,自牛、羊腐蹄病的发生与缺锌的关系被证实后,国内外兽医工作者通过补锌防治牛、羊腐蹄病,取得了良好效果.     

Effect of Parenteral Selenium Administration to Sheep on Prevalence and Recovery from Footrot

Background: Insufficient intake of selenium (Se) is common in many regions, and can contribute to increased susceptibility to and prolonged recovery from infectious diseases. Objective: To determine the effect of Se administration in decreasing the severity and prevalence of footrot in sheep. Animals: Thirty‐eight footrot‐affected and 19 nonaffected sheep from a commercial flock of known high incidence of footrot. Methods: Placebo‐controlled, prospective, 15‐month clinical trial. Footrot‐affected sheep were randomly assigned into 2 groups (n = 19) and injected with either 5 mg Se (footrot [FR]‐Se) or saline (FR‐Sal) at 1‐month intervals for the duration of the study. Unaffected sheep (controls) received no treatment. Sheep feet were examined, trimmed, and scored for footrot with a scale of 0 (no footrot) to 4 (extensive) at 0, 3, 6, 9, and 15 months. Sheep were also bled at time 0 and then at 3, 6, and 15 months to assess whole blood Se concentrations. Results: At time 0, control sheep (255 ± 11 ng/mL) had higher (P < .05) whole blood Se concentrations compared with FR‐Se (205 ± 12 ng/mL) and FR‐Sal (211 ± 14 ng/mL) sheep. By 6 months, FR‐Se sheep (317 ± 9 ng/mL) had whole blood Se concentrations greater (P < .05) than both control (281 ± 14 ng/mL) and FR‐Sal (277 ± 16 ng/mL) sheep. FR‐Se ewes showed a faster decline in highest lesion score at 3 (P= .012) and 6 (P= .0036) months, and a greater decrease in the number of feet with foot score >0 at 6 (P= .020) months compared with FR‐Sal ewes. Sheep with blood Se concentrations <300 ng/mL were at 3.5 times greater risk (1.1–12.1 confidence interval, odds ratio) for FR, although this relationship was only significant (P= .04) at 6 months of the study. Conclusions and Clinical Importance: In sheep with footrot, improved Se status in conjunction with routine control practices result in more rapid improvement of foot lesions.     

基于~1H NMR技术的急性腐蹄病奶牛血清代谢组学分析

通过~1H核磁共振(~1H NMR)技术结合主成分分析(PCA)和正交偏最小二乘判别分析法(OPLS-DA),分别分析奶牛在患有急性腐蹄病时内源性代谢产物的变化,研究腐蹄病的发生对奶牛代谢过程的影响,寻找差异表达的代谢物。运用~1H NMR技术获得两组奶牛血清代谢谱。所采集的数据经过模式分析获得差异代谢物。结果急性腐蹄病组与健康对照组相比,奶牛血清内差异性代谢物为21个。结果显示,在奶牛发生腐蹄病时体内糖类、氨基酸、脂类和能量代谢均发生了改变。表明结合~1H NMR谱检测分析的急性腐蹄病组对照组比对的差异代谢物,全景式地揭示了腐蹄病发生过程中奶牛机体内发生了广泛的代谢紊乱,为今后深入探究腐蹄病的发病机理和新的防治策略奠定了基础。     

Isolation,Identification and Sequence Analysis of Leukotoxin Gene lktA1 of Fusobacterium necrophorum of Cow Footrot

For separation and purification of Fusobacterium necrophorum of cow footrot, and analysis of genetic relationship with other strains, the hoof ministry swab samples were detected by PCR based on specific primers of leukotoxin gene, and genomic DNA were isolated from PCR positive samples of Fusobacterium necrophorum culturing in anaerobic medium.The genes of leukotoxin were cloned and sequenced.The results showed that nine of hoof ministry swab samples were all PCR positive samples, and we obtained Fusobacterium necrophorum pure culture from one of the samples which named bFR13-1.The gene sequencing results indicated that the homologies of leukotoxin gene nucleotide sequence of bFR13-1 strain compared with H05, A25 and B35 strains from GenBank were 98.40%, 98.35% and 90.79%, respectively, and the homologies of deduced amino acid sequence were 97.7%, 97.6% and 89.0%, respectively.Phylogenetic tree analysis results showed that leukotoxin gene of Fusobacterium necrophorum bFR13-1 and H05 had high homology and bFR13-1, H05 and A25 showed a close genetic relationship.The result indicated that leukotoxin showed variability between different Fusobacterium necrophorum isolated strains, and it was worth to study whether this change and pathogenicity of Fusobacterium necrophorum were related.     

Within-flock transmission of sheep scab in naive sheep housed with single infested sheep.

The within flock transmission of sheep scab was studied in two trials, which lasted 14 and 12 weeks, respectively. A total of 40 non-infested, scab-naive sheep were divided into six groups of between 6 and 20 individuals. Each group was subsequently housed with a single infested index case, carrying scab lesions of different ages. The groups of sheep in both trials were video recorded continuously and all the sheep were individually examined on a weekly basis. The occurrence of transmission was measured in two ways: first, by the detection of early scab lesions during clinical examination and, second, by an increase in the rubbing of individual sheep as noted from the analysis of the video recordings. These two methods complemented each other in predicting the week on which transmission occurred. Overall, transmission was detected in 34 of the 40 scab-naive sheep. Transmission was shown to occur at about the time when the population of adult mites in lesions on index cases reached their peak numbers. The highest number of mites at this time, however, differed markedly between index sheep. There was no obvious relationship between the incidence of transmission and the time index sheep spent rubbing each day or other index sheep variables, including the age of the lesion or the time since the introduction to the scab free sheep.