保护性耕作对黄土旱塬玉米土壤呼吸及微生物数量的影响

研究了实施保护性耕作10年后秸秆还田和免耕对土壤可培养微生物数量和CO2释放的影响,采用LI COR 6400 09土壤气室连接红外线气体分析仪测定了玉米（Zea mays cv.Zhongdan No.2）土壤呼吸速率,采用平板涂抹计数法测定了根际土壤细菌、真菌和放线菌数量。结果表明,免耕和秸秆还田处理玉米花期土壤呼吸速率降低了8.3%和7.8%,玉米收获期土壤呼吸速率降低了15.5%和13.6%;土壤10 cm处地温与土壤呼吸速率变化趋势一致,且在传统耕作处理下最高;与传统耕作相比,免耕和秸秆还田不同程度地增加了根际土壤细菌、真菌和放线菌的数量,但各类微生物数量之间的比例恒定;土壤呼吸速率与3类根际土壤微生物的数量呈负相关,但不显著。可利用免耕和秸秆还田提高黄土旱塬土壤碳库贮量。     

Anaesthetic management for balloon dilation of cor triatriatum dexter in a dog

A three-month-old female Rottweiler puppy was referred for intravascular correction of a previously identified cor triatriatum dexter. Echocardiography confirmed the presence of a hyperechoic membrane that divided the right atrium into a cranial and caudal chamber. A foramen in this membrane allowed the blood to flow from the caudal to the cranial chamber. Balloon dilation of the defect under transthoracic echocardiographic guidance was scheduled for the following day. The dog was premedicated with 0.5 μg/kg sufentanil and 0.2 mg/kg midazolam administered intravenously. General anaesthesia was induced with 2 mg/kg propofol and maintained with inhaled isoflurane in oxygen; at the same time, a constant rate infusion of 0.5 μg/kg/h sufentanil was administered by means of an infusion pump. Uneventful ventricular and supraventricular tachyarrhythmias developed during the placement of catheters and balloon dilation. At the end of procedure, when the guide wire and balloon catheter were removed, normal sinus rhythm was observed. To the authors’ knowledge, no previous reports have described the anaesthetic management of a balloon dilation procedure for cor triatriatum dexter in dogs.     

梅山与长大母猪下丘脑-垂体-卵巢轴Kiss1和GPR54基因的表达差异

研究早熟与晚熟品种母猪下丘脑-垂体-卵巢轴Kiss1和GPR54基因的表达差异。选用8头梅山母猪与12头长大(LY)母猪为研究对象,梅山母猪于70 d和100 d屠宰,LY母猪于70、100 d和199 d屠宰,收集血清及下丘脑、垂体、卵巢组织样品。ELISA检测血清瘦素(Leptin)和雌二醇(E2)水平,PCR克隆梅山与LY母猪Kiss1基因编码序列,实时荧光定量PCR检测母猪下丘脑、垂体、卵巢组织Kiss1和GPR54基因表达水平。结果表明:梅山与LY母猪Kiss1基因编码序列相似性为100%;梅山与LY母猪初情期下丘脑Kiss1基因表达量极显著高于垂体与卵巢(P<0.01),卵巢GPR54基因表达水平显著高于下丘脑与垂体(P<0.05)。梅山母猪下丘脑-垂体-卵巢轴Kiss1基因表达水平都显著高于相同日龄和初情期LY母猪(P<0.05),梅山母猪血清Leptin水平极显著高于相同日龄LY母猪(P<0.01)。而E2水平显著高于100 d与初情期LY母猪(P<0.01)。Leptin与下丘脑Kiss1和GPR54基因表达呈显著正相关(P<0.05),而E2仅与下丘脑Kiss1基因表达有极显著正相关关系(P<0.01);梅山与LY母猪Kiss1基因编码区序列相似性为100%,梅山母猪下丘脑-垂体-卵巢轴上kiss1基因表达量较LY母猪高,主要原因可能是初情日龄早,下丘脑Kiss1基因表达水平的高低与血清Leptin和E2浓度密切相关。     

Alternative method to facilitate resolution of paraphimosis after penile trauma in the horse

Inflammation associated with traumatic injury to the penis is characterised by pain, heat and oedema. Ensuing penile swelling interferes with retraction of the penis into the prepuce, resulting in paraphimosis. This report describes the use of a 5 l capacity pressure infusion bag to reduce penile oedema in three horses. This technique provided complete resolution of oedema and associated paraphimosis in approximately 1 h. The use of the bag, along with an abdominoinguinal bandage, a plastic funnel suspensory device, or a penile repulsion device (Probang) to avoid recurrence, offers a novel treatment that may be performed with the horse sedated.     

Multiplex real-time PCR SYBR Green for detection and typing of group III Clostridium botulinum

Clostridium botulinum type C and type D belonging to the group III organisms, are mainly responsible for animal botulism outbreaks. Clinical signs alone are often insufficient to make a diagnosis of botulism and a laboratory confirmation is required. Laboratory confirmation can be performed by demonstrating the presence of botulinum neurotoxins in serum, gastrointestinal contents, liver, wound of sick or dead animals, or by demonstrating the presence of C. botulinum in gastrointestinal contents, liver, and wound. Demonstration of spores in gastrointestinal contents or tissue of animals with clinical signs indicative of botulism reinforces the clinical diagnosis. With the aim of detecting and typing C. botulinum group III organisms, a multiplex real-time PCR SYBR Green was developed and in-house validated. Selectivity, limit of detection, relative accuracy, relative specificity, relative sensitivity, and repeatability of the method were investigated. The multiplex real-time PCR SYBR green used showed a 100% selectivity, 100% relative accuracy, 100% relative specificity, 100% relative sensitivity and a limit of detection of 277 and 580 DNA copies for C. botulinum type C and C. botulinum type D, respectively. The method reported here represents a suitable tool for laboratory diagnosis of type C and D botulism and for testing a large number of samples collected during the animal botulism surveillance and prevention activities.     

Assessing resistance against macrocyclic lactones in gastro-intestinal nematodes in cattle using the faecal egg count reduction test and the controlled efficacy test

The main objective of the present study was to evaluate the accuracy of the faecal egg count reduction test (FECRT) to assess the resistance status of ivermectin (IVM)-resistant isolates of the cattle nematodes Ostertagia ostertagi and Cooperia oncophora, using the controlled efficacy test (worm counts) as a reference. The second objective was to investigate whether both IVM-resistant isolates showed side-resistance against moxidectin (MOX) under controlled conditions. Thirty male Holstein calves were experimentally infected with 25,000 L3 of an IVM-resistant O. ostertagi isolate and 25,000 L3 of an IVM-resistant C. oncophora isolate. Twenty-eight days later the calves were randomly divided into 2 treatment groups and 1 untreated control group. Animals in groups 1 and 2 received MOX (Cydectin(?) 1%, Pfizer) and IVM (Ivomec(?) 1%, Merial) respectively, by subcutaneous injection at a dose rate of 0.2mg/kg bodyweight. Faecal samples were collected 7 and 14days after treatment and animals were necropsied 14/15days post-treatment. Both the FECRT and the controlled efficacy test demonstrated that the O. ostertagi and C. oncophora isolates were resistant against IVM, with efficacies below 90%. The IVM-resistant O. ostertagia isolate was still susceptible to MOX treatment, as shown by over 99% reduction in egg counts and worm burden. The FECRT suggested borderline resistance against MOX in the IVM-resistant C. oncophora isolate, with egg count reductions between 97% (95% CI: 76; 100) at day 7 and 86% (95% CI: 49; 96) at day 14. However, the controlled efficacy test clearly showed MOX-resistance, with a decrease of only 31% (95% CI: -12; 57) in C. oncophora worm numbers. After MOX treatment, a significantly lower number of eggs per female C. oncophora worms was counted compared to the control group (43% reduction). Due to this reduced fecundity, the FECRT may fail to detect MOX-resistance.     

Dorsal laminectomy for caudal cervical spondylomyelopathy: postoperative recovery and long-term follow-up in 20 dogs

OBJECTIVE: To evaluate the postoperative morbidity and long-term outcome of dogs after dorsal laminectomy for caudal cervical spondylomyelopathy (CCSM). STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Twenty dogs with CCSM. METHODS: Medical records of dogs treated by dorsal laminectomy for CCSM at North Carolina State University and Colorado State University between 1989 and 1999 were reviewed. Information on signalment, onset, progression and duration of clinical signs, diagnostic testing, sites of dorsal laminectomy, postoperative complications, length of hospitalization, and the ambulatory status on discharge was recorded. A minimum follow-up of 7 months was required for inclusion in the study. Neurologic status was graded (0 to 5) preoperatively, 2 days after surgery, and at the time of the study (final score). Improvement or worsening of the neurologic status was assessed by comparison of different scores for each dog. Additional follow-up information was obtained by means of a detailed telephone questionnaire directed at both the owner and referring veterinarian. RESULTS: Mean duration of clinical signs before surgery was 4.9 months. At admission, 15 dogs were ambulatory and 5 were nonambulatory. Neurologic status worsened in 70% of dogs 2 days after surgery but improved in all but 1 dog over the long term. Mean time to optimal recovery was 3.6 months. Long-term follow-up ranged from 7 months to 9 years (mean +/- SD, 3.2 +/- 2.4 years). Four dogs had confirmed recurrence; 2 other dogs may have had recurrence. CONCLUSIONS: Dorsal cervical laminectomy is an effective treatment for CCSM in those dogs with dorsal compression or multiple sites of involvement. CLINICAL RELEVANCE: Although most dogs' neurologic status transiently worsened after surgery, long-term outcome and recurrence rates were comparable to those seen with other surgical techniques for CCSM.