Intestinal surgery in small animals: historical foundations,current thinking,and future horizons

Intestinal wounds require precise closure after intestinal biopsy, enterotomy, or enterectomy in small animals. Preexisting factors such as intra‐abdominal sepsis and hypoalbuminemia as well as poor surgical technique increase the risk of intestinal dehiscence, with considerable negative impact on patient morbidity and mortality. Live dog studies have demonstrated the dangers of mucosal eversion especially in the septic abdomen. Approximating patterns preserve luminal diameter, heal optimally, and have equal bursting strength compared with inverting patterns after 24 hours. Simple interrupted and simple continuous suture patterns and disposable skin staples are established alternatives for manual wound closure. Knotless quilled suture currently used in laparoscopic gastropexy techniques shows bursting strength equal to monofilament sutures in dog cadaveric intestine. Dehiscence rates with hand sewn vs titanium automated stapling anastomosis are similar in uncomplicated cases; however, auto stapling devices may be the preferred method of anastomosis when preexisting abdominal sepsis is present and when patient size allows it. Regardless of the technique, current standard of care involves leak testing and omental wrapping, followed by early postoperative feeding. The past decade has ushered in an exciting new era of laparoscopic assisted techniques that have the potential to reduce postoperative pain and patient morbidity. An understanding of these applications will establish the future of minimally invasive small animal intestinal surgery for veterinary specialists. In summary, surgeons have a variety of methods at their disposal for optimal clinical outcome in small animal intestinal surgery.     

短期休牧对克氏针茅草原植物群落物种多样性及稳定性影响研究

文章采用野外植物样方采取及实验室数据分析相结合的方法,以阿巴嘎旗北部牧户常年放牧和隔年休牧的冬季草场为例,探讨短期休牧对克氏针茅草原植物物种多样性及群落稳定性的影响。结论如下:(1)两个草场植物群落内植物数量差异不大,主要差异表现在主要植物的平均重要值及两个草场仅有2对共优种。此外,短期休牧冬季草场的禾本科植物比重提升的同时,一年生藜科植物也显著提升;(2)短期休牧冬季草场的植物群落物种多样性指数略高于常年放牧冬季草场,但差异不显著;(3)两个草场植物群落处于中等相似水平,植物种间存在分异化趋势;(4)短期休牧冬季草场植物群落总体呈微弱正联结,种间联结松散,处于正向演替阶段,常年放牧冬季草场呈微弱负相关,群落较不稳定,存在一定退化风险;(5)两个草场的植物群落离稳定性都有一定差距,但短期休牧冬季草场植物群落稳定性略好于常年放牧冬季草场。可见,短期休牧有利于克氏针茅草原植物群落物种多样性和稳定性保持。     

安普霉素对仔猪内分泌的调控作用及血液生化指示的影响

采用单因子试验设计 ,28日龄大长北三元杂交断奶仔猪72头随机分为3组 ,研究饲料中添加不同剂量的安普霉素 (0、20、90mg/kg)对仔猪内分泌的调控作用及血液生化指标的影响。试验期为4周。结果表明 :仔猪日粮中添加90mg/kg的安普霉素可促进机体与生长有关的内分泌活动 ,提高内源激素 (生长激素、胰岛素、甲状腺激素T3)水平 (P<0.05),从而促进肌肉蛋白沉积 ;并具有显著降低血液中氨、尿素氮含量和提高血糖水平的作用 (P<0.05) ,表明安普霉素对仔猪具有增加氮沉积 ,促进蛋白质合成、抑制蛋白质分解的作用     

Effects of sodium nitroprusside after load reduction and/or atropine pre-treatment prior to dexmedetomidine administration on cardiovascular variables in dogs

The purpose of this study was to determine the cardiovascular effects of sodium nitroprusside (SNP)‐induced after load reduction in dogs administered dexmedetomidine (DEX). Using a randomized crossover design and allowing at least 2 weeks between treatments 12 adult hound dogs of either sex weighing 22 ± 1.7 SD kg were anesthetized by face mask administration of 2.9% ET sevoflurane to facilitate instrumentation prior to administration of treatment drugs. Dogs were intubated and instrumented to enable measurement of heart rate (HR), systolic (SAP), mean (MAP) and diastolic (DAP) arterial pressures, mean pulmonary arterial pressure (PAP), pulmonary capillary wedge pressure (PCWP), central venous pressure (CVP), pulmonary arterial temperature (TEMP), and cardiac output (CO). Systemic (SVR) and pulmonary vascular resistances were calculated. Following completion of instrumentation dogs were allowed to recover for 40 minutes. After collection of baseline data, dogs were administered one of four treatments at T–10 minutes prior to injection of DEX (500? g M^–2 IM): 1) saline (SAL); 2) atropine (ATR, 0.02 [n = 6] or 0.04 [n = 6] mg kg^–1 IM); 3) SAL + SNP (infused at 1–10 ?g kg^–1 minute^–1, IV as needed to maintain MAP between 90–110 mm Hg; or 4) ATR + SNP. Cardiovascular data were collected at T‐20 minutes prior to administration of DEX, T‐5 and at 5, 10, 20, 30, 40, and 60 minutes following DEX. Data were analyzed using anova for repeated measures with post hoc differences between means identified using Bonferroni's method (p < 0.05). Differences in ATR dose were not found to be significant and thus results for ATR dose groups were pooled. Administration of SAL (dexmedetomidine alone) was associated with decreases in HR and CO and increases in SAP, MAP, DAP, CVP, and SVR. Administration of ATR was associated with an increase in HR and CO compared with SAL. Administration of SNP was associated with an increase in HR and CO and a decrease in SVR, MAP and CVP compared with SAL. Administration of SNP + ATR was associated with effects similar to that of SNP or ATR alone and resulted in an additive increase in CO. We conclude that SNP‐induced afterload reduction with or without atropine is effective in mitigating DEX‐induced impairment of cardiovascular function.     

大针茅对放牧生态系统植物群落地上生物量的调控作用

通过放牧梯度试验,研究放牧对内蒙古典型草原5种优势植物在个体、种群和群落水平上的影响,探讨大针茅(Stip grandis)对放牧生态系统植物群落地上生物量的调控作用。结果表明:个体水平,中轻度放牧对以大针茅和糙隐子草(Cleistogenes squarrosa)为代表的丛生禾草株高影响较小,对以羊草(Leymus chinensis)、黄囊苔草(Carex korshinskyi)和米氏冰草(Agropyron michnoi)为代表的根茎型禾草株高影响较大,植物株高的降低与个体地上生物量减少呈显著正相关。种群水平,大针茅种群生物量对放牧的响应迟缓,羊草、米氏冰草、糙隐子草和黄囊苔草种群生物量的减少与多度减少呈显著正相关。群落水平,大针茅的耐牧性使其成为资源重配的获益者,轻中度放牧干扰下,其地上生物量的补偿生长缓冲了放牧对群落的影响,对维持群落生产力与功能稳定性起重要的调控作用。     

不同利用方式对贝加尔针茅草原土壤活性有机碳的影响

土壤活性有机碳能够准确反映土壤有效性,表征土壤质量变化,是探索可持续草地管理措施的关键指标之一。以内蒙古贝加尔针茅草原为研究对象,采用围封、放牧和刈割野外控制试验,探讨不同利用方式对土壤有机碳（SOC）和活性有机碳的影响,发现不同利用方式下土壤SOC含量表现为围封>刈割>放牧,其中围封区和刈割区土壤SOC含量显著大于放牧区,围封区与刈割区土壤SOC含量差异不显著,在土壤活性有机碳中土壤可溶性有机碳（DOC）含量表现为放牧>围封>刈割。土壤微生物量碳（MBC）和土壤易氧化有机碳（ROC）含量均表现为围封>刈割>放牧,围封区与刈割区土壤MBC和土壤ROC平均含量差异不显著,且均显著大于放牧区。土壤MBC、ROC和SOC之间呈极显著相关性（P<0.01）。土壤ROC和土壤MBC与土壤全氮和土壤全磷呈极显著相关性（P<0.01）。围封与刈割有利于土壤SOC、MBC、ROC的提升,放牧对土壤DOC有一定累积作用。围封和刈割增强了土壤SOC的稳定性,活性有机碳与土壤有机碳和土壤理化性质密切相关,能够敏感地反映土壤有机碳的变化。     

沙质草地、高平原草地牧草总糖与还原糖含量变化

研究了沙质草地与高平原草地六种牧草的总糖含量与还原糖含量变化情况.结果表明:沙质草地与高平原草地供试牧草的总糖含量变化(除糙隐子草外)和还原糖含量变化不同;除羊草和寸草苔外,其余几种牧草的还原糖含量都是高平原草地高于沙质草地.