Population-based study of fecal shedding of Clostridium perfringens in broodmares and foals

OBJECTIVE: To determine the percentage of broodmares and foals that shed Clostridium perfringens in their feces and classify the genotypes of those isolates. DESIGN: Prospective cross-sectional study. ANIMALS: 128 broodmares and their foals on 6 equine premises. PROCEDURES: Anaerobic and aerobic bacteriologic cultures were performed on feces collected 3 times from broodmares and foals. All isolates of C. perfringens were genotyped. RESULTS: Clostridium perfringens was isolated from the feces of 90% of 3-day-old foals and 64% of foals at 8 to 12 hours of age. A lower percentage of broodmares and 1- to 2-month-old foals shed C. perfringens in their feces, compared with neonatal foals. Among samples with positive results, C. perfringens type A was the most common genotype identified (85%); C. perfringens type A with the beta2 toxin gene was identified in 12% of samples, C. perfringens type A with the enterotoxin gene was identified in 2.1% of samples, and C. perfringens type C was identified in < 1% of samples. CONCLUSIONS AND CLINICAL RELEVANCE: Clostridium perfringens was identified from the feces of all but 6 foals by 3 days of age and is likely part of the normal microflora of neonatal foals. Most isolates from broodmares and foals are C. perfringens type A; thus, the clinical relevance of culture results alone is questionable. Clostridium perfringens type C, which has been associated with neonatal enterocolitis, is rarely found in the feces of horses.     

Serological responses of mares and weanlings following vaccination with an inactivated whole virus equine herpesvirus 1 and equine herpesvirus 4 vaccine

Equine herpesvirus 1 (EHV-1) is a major cause of respiratory disease and abortion in horses worldwide. Although some vaccines have been shown experimentally to reduce disease, there are few reports of the responses to vaccination in the field. This study measured antibody responses to vaccination of 159 mares (aged 4-17 years) and 101 foals (aged 3-6 months) on a large stud farm with a killed whole virus EHV-1/4 vaccine used as per the manufacturer's recommendations. Using an EHV glycoprotein D (gD)-specific ELISA and a type-specific glycoprotein G (gG) ELISA, respectively 13.8 and 28.9% of mares, and 42.6 and 46.6% of foals were classed as responding to vaccination. Additionally, 16.4 and 17.6% of mares were classified as persistently seropositive mares. Using both assays, responder mares and foals had lower week 0 mean ELISA absorbances than non-responder mares and foals. Responder mares were ten times more likely to have responder foals, and non-responder mares were six times more likely to have non-responder foals than other mares using the gG ELISA. Mares aged 7 years or less and foals aged 4 months or more were more likely to respond to vaccination than animals in other age groups. There was no association between response of mares and the number of previous vaccinations received and persistently seropositive mares did not respond to vaccination. This study documents the responses of mares and foals to vaccination in a large scale commercial environment in 2000, and suggests that knowledge of antibody status may allow a more selective vaccination strategy, representing considerable savings to industry.     

高校新馆安装摄像监控系统应注意的细节问题

对高校图书馆新馆在设计安装摄像监控系统时,提出要注意的一些细节上的问题,从功能需求,摄像头选型、安装位置、录像保存时间等细节问题上提出诸多的注意事项,从而保证系统投入使用后能正常有效运行。     

凡纳滨对虾高位池养殖微生物生态改良技术

目前,光合细菌、硝化细菌、反硝化细菌、乳酸杆菌、蛭弧菌、芽孢杆菌、酵母菌等种类繁多的水产生态制剂正广泛用于对虾养殖业。使用过程中,人们发现：菌类产品存在菌种单一或杂合,不能适应复杂多变的水体条件;保存困难,存活时间短;水体大量微生物存在时,较难形成优势菌落;处理水环境效果不突出,难以替代化学处理方法等诸多缺点。     

Management, breeding, and health records from a captive colony of pekin robins (Leiothrix lutea), 2001 - 2010

Pekin robins (Leiothrix lutea) were once the most widely kept softbills in captivity. As a result of the Convention on the International Trade of Endangered Species of Fauna and Flora (CITES-1997), the worldwide trade of wild-caught pekin robins has been prohibited due to the depletion of native populations of this species. In Brazil, as in other countries, pekin robins imported prior to the enactment of the CITES have disappeared from aviaries because the end of the birds' natural life span has passed, and only very few captive-bred pekin robins now exist. While captive propagation fails to address the primary causes of wild bird population decline, it might help the recovery of populations of this species. This article presents records made over a 10-yr period of a captive colony of pekin robins. Emphasis is placed on the management of the flock, the ailments affecting the birds, and the findings associated with bird losses. The main causes of bird losses included rearing management failures and age-related disorders.     

Improved husbandry to control an outbreak of rainbow trout fry syndrome caused by infection with Flavobacterium psychrophilum

CASE DESCRIPTION: A cohort of 35,200, 13-week-old, female rainbow trout at a fish farm was evaluated because of a 2-week history of anorexia and lethargy and a mortality rate of approximately 100 fish/d. CLINICAL FINDINGS: Affected fish were lethargic and thin and had disequilibrium, bilateral exophthalmia, pale red gills and kidneys, red-tinged coelomic fluid, and pale brown livers. Some fish were differentially pigmented bilaterally. The presumptive diagnosis was bacterial or viral septicemia. The definitive diagnosis was rainbow trout fry syndrome caused by infection with Flavobacterium psychrophilum. TREATMENT AND OUTCOME: A strategy for controlling the outbreak based on reducing pathogen numbers in affected tanks and reducing pathogen spread among tanks was developed. The option of treating with antimicrobial-medicated feed was discussed with the farmer, but was declined. After changes were made, mortality rate declined quickly, with no more deaths within 10 days after the initial farm visit. CLINICAL RELEVANCE: Bacterial coldwater disease is the most common manifestation of infection with F psychrophilum in fingerling and adult rainbow trout. However, the organism can also cause rainbow trout fry syndrome. This condition should be included on a list of differential diagnoses for septicemia in hatchery-reared rainbow trout fry.     

甜叶菊渣对肉兔生产性能和养分消化率的影响

甜叶菊又名甜菊、甜草和甜茶,系多年生菊科草本植物,原产于南纬22～24°,西经55～56°的巴拉圭东北部与巴西接壤的阿曼拜山脉,当地的印第安土著居民将其作为甜味剂使用已经有几百年的历史.     

华南地区17个农作物病原真菌菌株间拮抗作用的初步研究

 通过PDA平板对峙试验研究了华南地区17种农作物病原真菌菌株之间的共生关系和拮抗关系,结果表明菌丝对峙生长可分为5种类型。稻小黑菌核病菌株与大部分供试菌株有明显的拮抗作用,稻黑粒病新月弯孢霉菌株与大部分供试菌株不能共生,花生冠腐病菌株的菌丝能覆盖大部分供试菌株的菌落,茶云纹叶枯病菌株、桑炭疽病菌株和柚子炭疽病菌株的菌落有明显的区别。     

Effects of insulation on the temperature within farrowing huts and the weaning weights of piglets reared on a commercial outdoor pig unit

The air temperatures inside uninsulated and insulated huts were recorded on an outdoor pig unit in the south of England between September 1997 and September 1998, and the herd's production parameters were also recorded. During the summer the temperatures inside some of the uninsulated huts exceeded 45 degrees C, but the temperatures inside the insulated huts were lower and fluctuated less. Despite the high temperatures, the weaning weight of piglets reared in the uninsulated huts were often higher than those of the piglets reared in the insulated huts, possibly as a result of the higher mortality of small piglets in the uninsulated huts, especially during the winter. The weaning weights of the piglets were higher during the summer.