Farm level and geographic predictors of antibiotic use in Sri Lankan shrimp farms

Black tiger shrimp Penaeus monodon farming is important for Sri Lanka's rural development plans. Consumer confidence is critical for the development and maintenance of export and domestic shrimp markets. Public concern about the use of antimicrobial drugs and chemicals on shrimp farms, however, could threaten market access. We sought to identify high-risk areas and farm-level risk factors for antimicrobial use to inform the core messages and strategic placement of extension programs to help farmers develop best management practices for antimicrobial use. We undertook a survey of 603 operating farms within the Puttalam district over 42 weeks. Lower stocking density and early harvest were associated with a lower risk of antimicrobial use, whereas standard management practices, including water treatment, feed supplements, probiotic use, pond fertilizing, disinfectant use, and pesticide use, were associated with increased risk. Spatial cluster detection found three significant clusters of antimicrobial-using farms. Antimicrobials were more likely to be used in areas with lower farm density. Some of our counterintuitive findings are discussed from a socioecological perspective. A comprehensive understanding of why antimicrobials are used on shrimp farms requires an evaluation of the physical, epidemiological, and socioeconomic factors.     

Comparison between Sri Lankan and Australian strains ofBabesia bovis in the vaccination of imported cattle in Sri Lanka

Summary A Sri Lankan strain ofBabesia bovis (designated A strain) was isolated from larval ticks and prepared for use as vaccine by syringe-passage in 20 splenectomised calves followed by irradiation. The A strain and a vaccine strain ofBabesia bovis (designated K strain) brought in frozen form from Australia were used to vaccinate 37 susceptible bulls imported from southern Australia. Rectal temperatures, packed cell volumes, parasitaemias and overt clinical signs were monitored for three weeks following vaccination. The results indicated that the A strain was slightly more virulent than the K strain but suitable for the vaccination of well-supervised cattle.

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Comparacion Entre Las Cepas Sri Lankan Y Australiana DeBabesia Bovis En La Vacunacion De Ganado Importado A Sri Lanka

Resumen Se aisló en Sri Lanka, una cepa deBabesia bovis (denominada cepa A), de larvas de garrapatas. Esta se preparó, para ser utilizada como vacuna, mediante el pasaje a través de 20 terneros esplenectomizados e irradiándola posteriormente. La cepa A y la cepa vacunal (cepa K) traída congelada de Australia, se utilizaron para inmunizar 37 toros susceptibles importados del Sur de Australia. Se tomó la temperatura rectal, el volumen corpuscular, la parasitémia y se registraron los síntomas clínicos de los animales vacunados, por un período de tres semanas. Los resultados indican, que la cepa A fue un poco más virulenta que la K, pero efectiva para la inmunización de animales bajo buena supervisión.

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Comparaison Entre Des Souches Sri-Lankaises Et Australiennes DeBabesia Bovis Pour La Vaccination Du Betail Importe A Sri-Lanka

Résumé Une souche sri-lankaise deBabesia bovis (dénommée souche A) a été isolée de larves de tiques puis préparée comme vaccin par passage à la seringue chez 20 veaux splénectomisés, suivi d'irradiation. On a utilisé la souche A, ainsi qu'une souche vaccinale deB. bovis apportée congelée d'Australie (dénommée souche K), pour vacciner 37 taureaux réceptifs importés d'Australie méridionale. Les températures rectales, les hématocrites, les parasitémies et les signes cliniques patents ont été consignés pendant les 3 seamines aprés la vaccination. Les résultats montrent que la souche A est légèrement plus pathogène que la souche K, mais cependant utilisable pour la vaccination de bovins bien surveillés.

     

Genetic diversity in Trypanosoma theileri from Sri Lankan cattle and water buffaloes

Trypanosoma theileri is a hemoprotozoan parasite that infects various ruminant species. We investigated the epidemiology of this parasite among cattle and water buffalo populations bred in Sri Lanka, using a diagnostic PCR assay based on the cathepsin L-like protein (CATL) gene. Blood DNA samples sourced from cattle (n = 316) and water buffaloes (n = 320) bred in different geographical areas of Sri Lanka were PCR screened for T. theileri. Parasite DNA was detected in cattle and water buffaloes alike in all the sampling locations. The overall T. theileri-positive rate was higher in water buffaloes (15.9%) than in cattle (7.6%). Subsequently, PCR amplicons were sequenced and the partial CATL sequences were phylogenetically analyzed. The identity values for the CATL gene were 89.6–99.7% among the cattle-derived sequences, compared with values of 90.7–100% for the buffalo-derived sequences. However, the cattle-derived sequences shared 88.2–100% identity values with those from buffaloes. In the phylogenetic tree, the Sri Lankan CATL gene sequences fell into two major clades (TthI and TthII), both of which contain CATL sequences from several other countries. Although most of the CATL sequences from Sri Lankan cattle and buffaloes clustered independently, two buffalo-derived sequences were observed to be closely related to those of the Sri Lankan cattle. Furthermore, a Sri Lankan buffalo sequence clustered with CATL gene sequences from Brazilian buffalo and Thai cattle. In addition to reporting the first PCR-based survey of T. theileri among Sri Lankan-bred cattle and water buffaloes, the present study found that some of the CATL gene fragments sourced from water buffaloes shared similarity with those determined from cattle in this country.     

Natural resistance of Sri Lankan village chicken to Salmonella gallinarum infection

1. An experiment was conducted to compare the natural resistance of an indigenous breed of local village chickens to Salmonella gallinarum with two commercial breeds: ISA Brown and ISA White layers under experimental conditions.

2. A total of 72 chickens from each of these breeds were randomly distributed to 4 pens to provide equal numbers of two replicate pens maintained as infected and control (uninfected). All chickens in infected groups were inoculated orally with 1 × 10⁸ CFU (1 ml dose) of a field isolate of S. gallinarum, at the age of 8 and 16 weeks given over 5 consecutive days. Growth performance, clinical signs, gross pathological lesions and antibody responses were measured.

3. A significantly higher mortality was observed in the brown layers compared with the white layers, and clinical signs and mortality were absent in village chickens. However, a large number of birds with gross lesions and high antibody titres were detected in village chickens, indicating that birds had the disease subclinically. Commercial breeds had a significantly higher body weight, feed intake and feed conversion efficiency.

4. There was a significantly lower proportion of positive reactors in village chickens in the whole-blood agglutination test (35%) compared to brown (100%) and white (90%) layers even after the second inoculation. Uninfected birds were negative in all groups. The indirect enzyme-linked immunosorbent assay confirmed these observations.

5. These results suggest that the indigenous breed had superior natural resistance to S. gallinarum than the commercial breeds.     

Feeding of Dairy Cattle in the Forest-Garden Farms of Kandy,Sri Lanka

A survey on feeding practices was conducted with 60 farmers belonging to four categories (15 farmers in each): male farmers without off-farm income (M^–), male farmers with off-farm income (M⁺), female farmers without off-farm income (W^–), and female farmers with off-farm income (W⁺). Data on herd size, feeds offered, milk production, chest girth, reproduction and management were collected monthly over a period of 1 year. In addition, samples of fodder and concentrates were collected monthly and analysed for dry matter (DM), organic matter (OM), crude protein (CP) and in vitro organic matter digestibility (OMD). Of the 550 rations analysed, grass was included in 99.8% of all rations, followed by gliricidia (65%), creepers (50%) and jak leaves (32%). Consequently, the rations were high in OMD (47–59%) and CP (7.8–23.5%). High-protein forage or coconut cake or both were also included as a supplement in 92% of the rations. Both M^– and W^– farmers had larger (p<0.001) herds (mean 1.8 animal units (AU) per household) than their counterparts with off-farm income (mean 1.44 AU/household), but only the male farmers without off-farm income achieved higher feeding levels (84.4 vs 65.6–72.1 g digestible organic matter (DOM)/kg^0.75 per day) and milk production (6.4 vs 5.3–5.7 L/lactating cow). The lower production of animals kept by female and M⁺ farmers was related to lower feeding levels. M^– farmers realized higher feeding levels than their M⁺ counterparts. W^– farmers did not collect extra feed in response to higher levels of production. It was concluded that dairy farming in the mid-country of Sri Lanka is particularly important for poorer households without income from off-farm employment.     

Absence of Wolbachia endobacteria in Sri Lankan isolates of the nematode parasite of animals Setaria digitata

Setaria digitata is an animal filarial parasite with natural hosts of cattle and buffaloes that causes mild disease conditions. Infection of non-permissive hosts such as goats, sheep and horses, by this nematode can cause cerebrospinal nematodiasis that leads to lumbar paralysis and the eventual death of the animals and inflicts considerable economic losses on livestock farmers. Wolbachia are obligate mutualistic endosymbionts for some filarial nematodes and are currently being targeted for the control of diseases caused by these parasites. However, little is known about the occurrence of this endosymbiont in the Setariidae family. In this work, worms collected from infected cattle in Sri Lanka were morphologically identified as S. digitata and tested for the presence of Wolbachia by PCR screening using the WSP- and Wolbachia-specific 16S rRNA and multilocus sequence typing primers that were designed to amplify the gatB, coxA, hcpA, ftsZ and fbpA sequences of Wolbachia. The presence of endobacteria in S. digitata was also examined by whole-mount immunofluorescence staining of the parasites and transmission electron microscopic studies. These analyses did not produce evidence of presence of Wolbachia or any other endosymbiotic bacteria in S. digitata, whereas such evidence was found in Brugia malayi, which was used as a positive control in this study.     

兽用消毒药的种类及其在养殖场中的合理使用

就兽用消毒药的种类、消毒药的选择、使用方法以及消毒效果的评价、养殖场的消毒管理等方面进行了介绍,为养殖场的消毒工作提供借鉴.     

养鸭场怎样使用消毒药

通过化学、物理等消毒方法来控制养鸭场疫病流行,消灭病原微生物(病毒、芽胞或无芽胞以及细菌)等,是养鸭场重要工作之一.鸭场消毒时要遵循三先三后的原则,即:先净道(运送饲料的道路),后污道(清粪车行驶的道路);先青年鸭舍,后产蛋鸭舍;先种鸭舍后商品鸭舍.……     

我国18个省份猪源肠球菌耐药调查及分析

为研究我国猪源肠球菌的耐药情况,本研究采集18个省市猪养殖场的粪便样品836份进行了肠球菌的分离鉴定,并通过琼脂稀释法测定11种抗菌药物的最小抑菌浓度.结果 显示:从836份样品中共分离出225株肠球菌,其中屎肠球菌106株,粪肠球菌56株,小肠肠球菌34株,鹑鸡肠球菌17株,铅黄肠球菌7株,坚忍肠球菌4株,Enter...     

沂南县养鸡场新城疫抗体水品监测

新城疫是危害养禽业的一种主要传染病,通过其抗体水平监测,分析免疫状态,对鸡群科学饲养,确保养鸡业健康发展。本次检测沂南县某蛋鸡场血样50份,分离血清,通过微量血凝及血凝抑制试验(HI)进行新城疫抗体水平监测。试验结果表明样品平均HI抗体效价为9.4log2,说明整场免疫合格,不需要补种,新城疫疫苗能达到最佳效果,能抵抗新城疫病毒的侵入。     

河北省部分猪场送检样品的猪蓝耳病抗体水平分析

为了解河北省规模猪场猪蓝耳病(PRRS)感染及免疫情况,选取2016—2017年河北省7个地区不同规模猪场送检的1 182份血样进行PRRS EILSA抗体检测,并对结果进行汇总分析。结果显示:7个地区不同规模猪场送检血样的阳性率均在80%以上,尤其是大型规模化猪场,抗体阳性率更高;地区间阳性率差异不大,均在75%~92%之间;散养和断奶仔猪群阳性率相对偏低。结果表明,河北省规模猪场的PRRS免疫效果较好;散养猪群和断奶仔猪群是发生PRRS的高风险猪群。结果提示,规范科学的PRRS免疫程序可以获得较好的免疫效果;应注重对散养和断奶仔猪群的免疫,根据抗体检测情况合理采取免疫措施。     

阿丝兰提取物添加剂在虾饲料中的应用

阿丝兰（Yuccaschkdigera）是生长在北美洲半沙漠地带的一种天然植物，其主要成分是皂苷（Saponin）。美国DPI研究所将阿丝兰中含有９０％活性有效成分的新鲜液汁浓缩，经高压低温处理制成饲料添加剂“美益净”（Micro－Aid），在美国专利注册，符合美国联邦食品和药物管制局法例（２１CFR１７２．５１０），被批准在动物饲料中使用犤注：我国的进口许可证号：（２００１）外饲准字４２７号犦。目前，已有超过４０多个国家使用，在畜牧和家禽饲养方面应用较成熟，在水产养殖方面的应用也逐渐展开。“美益净”有抑制动物体内尿素酶降低排…     

兰州地区部分奶牛场子宫内膜炎病原菌分离鉴定及抗生素耐药性研究简

为了探明兰州地区奶牛子宫内膜炎病原菌区系分布及抗生素耐药情况,指导临床合理用药。笔者对从兰州地区3个规模化奶牛场采集的47份奶牛子宫内膜炎样品进行了细菌分离鉴定,同时对分离鉴定出的4种主要病原菌采用纸片扩散法（K-B法）进行了抗生素耐药性检测。病原菌区系分布结果表明,引起兰州地区奶牛子宫内膜炎的病原菌主要为化脓隐秘杆菌（37.1%）、大肠杆菌（24.2%）、屎肠球菌（22.6%）和无乳链球菌（16.1%）。抗生素耐药性结果表明,4种主要病原菌对大部分抗生素均产生了不同程度的耐药性,尤其是对青霉素、复方新诺明、奥复星和杆菌肽耐药性最为严重,其耐药率为60%～100%。对4种病原菌均较敏感的药物主要有头孢他啶、先锋霉素V和氟苯尼考,其敏感度达100%。     

湖南省部分规模猪场保育仔猪细菌感染调查及药敏检测分析

为调查规模猪场保育仔猪的细菌感染情况,文章对湖南常德、怀化、郴州等地10个规模猪场80头病、死仔猪进行细菌分离和药敏试验。结果显示:共在70头仔猪病料中分离到细菌,分离率为87.5%(70/80),其中大肠杆菌、猪链球菌、副猪嗜血杆菌、巴氏杆菌感染分别占52.5%(42/80)、48.8%(39/80)、30.0%(24/80)、15.0%(12/80),两种或两种以上细菌混合感染39头,占48.8%(39/80)。通过对分离菌株进行药敏试验,猪链球菌、副猪嗜血杆菌、巴氏杆菌对头孢曲松、多西环素、氟苯尼考、恩诺沙星较为敏感,而大肠杆菌则耐药严重,部分菌株对常用药物均耐药。可见规模猪场保育仔猪细菌混合感染情况较多,且耐药性严重的大肠杆菌为常见耐药菌之一。猪场应针对具体细菌感染情况采取针对性的用药方案,方可达到用药目的。该调查为湖南规模猪场保育仔猪细菌性疾病防控及指导用药提供了参考。     

2021年山东省家禽养殖场生物安全水平问卷调查

为了解山东省家禽养殖场的生物安全水平,以问卷调查方式,对养殖场基本信息、场内区域划分、免疫接种、引种购进、消毒、饲养管理等问题展开调查。经预调查后,2021年6—7月在全省范围内开展本次调查。在全省16个地级市,采用随机抽样方式,每地级市抽检1~2个县(市、区);应用配额采样方式,在县市域内选取蛋鸡养殖场、肉鸡养殖场以及种禽场各1家。共收到有效问卷141份,分别来自12个地级市36个县(市、区),其中来自蛋鸡养殖场、肉鸡养殖场和种禽场占比分别为63.83%、26.95%和9.22%。所调查养殖场中,按照管理区、生产区、生活区进行区域划分的133家,一半以上的养殖场能做到每周至少消毒1次;137家养殖场有免疫计划,而无免疫计划的只有4家,包括蛋鸡场1家、肉鸡场3家。肉鸡场没有隔离场所的占比最高,达44.7%。106家养殖场对患病动物进行无害化处理。结果表明,所调查家禽养殖场在区域划分、区域管理、消毒管理、环境控制等生物安全方面都进行了相关的设计和应用,在一定程度上,能够起到预防致病因子侵入、阻挡病原微生物扩散的作用,但不同类型养殖场的生物安全水平并不均衡,因此养殖场需继续提高生物安全意识,逐步建立适用于本场的生物安全体系。     

Calf-related Drug Use on Holstein Dairy Farms in Southwestern Ontario

Calf-related drug use was studied on 104 randomly selected Holstein dairy farms in southwestern Ontario between October 1980 and July 1983. About 20% of dairy farmers were observed to administer antimicrobials preventively to healthy newborn calves (primarily as commercial “cocktails” of various antimicrobials, vitamins and minerals given in an oral bolus form) at some time during the year. About 30% of the farmers were observed to use vitamins (primarily vitamins A,D and E) preventively. The pattern of types of antimicrobials used preventively appeared to be different from the pattern seen for therapeutic use. Chloramphenicol was the single most commonly used therapeutic antimicrobial in this population of calves, accounting for some 30% of overall therapeutic antimicrobial use. In this study population, the prophylactic use of antimicrobials was associated with a decreased risk of being treated for pneumonia, and of dying, but an increased risk of being treated for scours. Case fatality rates for calves treated therapeutically varied, depending on the antimicrobial used and the routine of treatment. Calves treated with penicillin consistently suffered the highest case fatality rates. Case fatality rates for calves treated with chloramphenicol were considerably higher for calves treated once per day than for calves treated twice per day. For instance, calves first treated for scours with chloramphenicol, if treated once per day, suffered a case fatality rate of 22%. For scouring calves treated twice per day the case fatality rate was just under five percent. Clinical field trials of specific antimicrobials used preventively and therapeutically are required to delineate the conditions under which they might be useful.     

规模化奶牛场阴离子盐使用要点

生产中使用阴离子盐可有效降低奶牛产后代谢疾病发病率.本文从阴离子盐作用机理、配方设计、现场管理三方面介绍了规模化奶牛场阴离子盐使用的要点.阴离子盐的作用机理主要是调节机体酸碱平衡、调节机体对钙的吸收和利用,可通过监测牛群尿液pH值调节其用量.配方设计要注意原料选择、钙和磷的浓度、阴离子盐添加量和碱性原料的使用.现场管理...     

畜禽养殖场粪污肥料化利用技术及工艺

本文就畜禽养殖场粪污肥料化利用技术的总体规划,生产技术及工艺,生产设施及设备要求,环境保护方案等问题做了简要论述。