奶牛酸中毒:蹄叶炎的暗示

奶牛乳酸中毒是和瘤胃内增加大量乳酸相关联的，而乳酸来自于含有瘤胃高发酵的碳水化合物日粮，或合有较低的有效纤维的牧草，或两者都有之。其症状包括两个分别不同的解剖区域，就是胃肠道和体液，同时又是和乳酸的产生、利用和吸收的效率和程度相关。临床表现的范围包括失去食欲到动物死亡。当瘤胃中的乳酸利用菌不断减少而乳酸产生菌不断增多时，乳酸就在瘤胃中聚集。酸中毒对动物身体生理学的系统影响有几方面，其中包括蹄叶炎，这是一种真皮弥漫性无菌性炎症。尽管营养是其发病基础，但病因学分析其起因包含大量的相互作用的因子，如代谢和消化紊乱，产后应激以及局部创伤等，这些因子又引起血管活性物质的释放从而导致脚部的退化变质。蹄叶炎的严重程度和酸中毒损害的频率、强度和持续时间相关。最主要的问题就是持续的脚部供血不足，导致趾间的局部缺血。由于高产奶量的牛群需要更多的能量从而频繁面对亚临床酸中毒和蹄叶炎的威胁，而良好的管理对预防蹄叶炎是相当重要的，好的饲喂和饲养管理可以减少疾病的发病率。     

Strength Characteristics and Failure Modes of Locking-Loop and Three-Loop Pulley Suture Patterns in Equine Tendons

Size 3-0 polydioxanone was used as a single strand, single braid (3 strands), or double braid (6 strands) to create six suture material-pattern combinations for equine tenorrhaphy: single-strand locking loop, single-braid locking loop, double-braid locking loop, single-strand three-loop pulley, single-braid three-loop pulley, and double-braid three-loop pulley. Maximum load to failure for the single-strand locking loop (46.1 +/- 2.9 newtons [N]) was less than for all other sutures (range, 103-155 N). The load required to form a 2 mm gap between tendon ends was greater for the single-braid three-loop pulley (66.7 +/- 6.9 N) and double-braid three-loop pulley (85.4 +/- 17.7 N) than any other sutures. The load required to produce a 10 mm gap was least for the single-strand locking loop (34.3 +/- 3.9 N) and greatest for the double-braid three-loop pulley (131.5 +/- 27.5 N). Gap between tendon ends at maximum load was greater for the single-braid (18.1 +/- 0.9 mm) and double-braid (19.2 +/- 2.2 mm) locking loops than for any other sutures. Suture material broke in 53% of the locking-loop tests but in only 17% of the three-loop pulley tests. Tendon matrix disruption accounted for 43% of the locking-loop failures and 77% of the three-loop pulley failures. The three-loop pulley pattern provided more support, less tendon distraction, and less tendon matrix constriction and distortion than the locking-loop pattern.(ABSTRACT TRUNCATED AT 250 WORDS)     

Electrosurgical Arthrotomy and Excision of Soft Tissue Masses in the Metacarpophalangeal Joint of the Horse

Electrosurgical arthrotomy and excision of infra-articular soft tissue masses from the metacarpophalangeal joint was performed in 12 horses. In six of the 12 horses, osteochondral fragments from the dorsoproximal aspects of the first phalanx were also removed. The electrosurgical scalpel afforded excellent intraoperative efficacy for arthrotomy and relatively bloodless excision of soft tissue masses without the need for a tourniquet. There were no complications associated with healing in 11 of the 12 horses. A retraction technique that used careful positioning of a Langenbeck periosteal elevator relative to the collateral ligaments provided access to both medial and lateral margins of intra-articular masses. With this technique, all masses could be removed through one central arthrotomy incision.     

Induction of Anesthesia Using Diazepam/Ketamine in Dogs with Complete Heart Block A Preliminary Report

Intravenous diazepam and ketamine were used to induce anesthesia in four dogs with complete heart block while cardiac and hemodynamic measurements were made. Immediately after induction there were minor changes in the measured variables. However, 5 minutes after injection, with the dogs supine and mechanically ventilated, cardiac output was reduced 41%. An additional 20 dogs with heart block had uncomplicated induction when this drug combination was used. The combination of diazepam and ketamine appears useful for inducing anesthesia in dogs with heart lesions, although further studies must be done to establish its value in such patients.     

Intraocular and Cardiopulmonary Effects of Low-dose Mannitol in the Dog

Fatal complications have been reported during anesthesia in dogs that received a standard (1–2 g/kg IV) dose of mannitol during intraocular surgery. A lower dose (0.25 g/kg IV), which had been shown to reduce intracranial pressure in humans, was evaluated during halothane anesthesia in dogs. There were no significant changes in intraocular pressure (IOP) or cardiovascular variables. This lower dose (0.25 g/kg IV) did not reduce IOP and would not be of benefit in dogs undergoing intraocular surgery.     

Triangulated Flap Technique for Nasofrontal Surgery Results in Five Horses

A modified bone-flap technique was used to expose space occupying lesions that involved the conchofrontal sinus, ethmoturbinates, and caudal nasal cavity in five horses. The most common clinical findings were chronic nasal discharge and upper airway obstruction. Surgical intervention was based on endoscopic and radiographic interpretation. The triangulated bone-flap technique increased surgical exposure to the conchofrontal sinus by almost twice the area observed in previously described surgical techniques. The major advantages were that this technique allowed excellent visualization, thorough palpation, and surgical manipulation within the sinus and associated structures. Complications were minimal. One horse was euthanized 1 month postoperatively with recurrence and spread of a mycotic granuloma. The technique extended the usefulness of the other four horses in a 9 to 24 month follow-up period, although the obstructing lesion recurred after 2 years in one of the four horses.     

Control of Senecio jacobaea L. (ragwort) by autumn or spring herbicide application

A range of herbicides was sprayed in October 1976 or May 1977 on grassland infested with S. jacobaea. Control, measured by reduction in the number of flowering stems in July 1977, was extremely good with all herbicides, October spraying gave 99% control of 5. jacohaea and is provisionally recommended for grassland which is to be cut for silage. Lutte contre Senecio jacobaea L. (séneçonjacobée) parun traitement herbicide d'automne ou de printemps Une série d'herbicides ont été appliqués en octobre 1976 ou en mai 1977 sur des herbages infestés de séneçon jacobée. L'éfficacité, mesurée par la réduction du nombre de tiges fleuries en juillet 1977, a été extrêmement bonne avec tous les herbicides. Le traitement d'octobre a détruit 99% de S. jacobaea; il est provisoirement recommande pour les prairies de fauche dont la recolte doit etre ensilee. Bekümpfung von Senecio jacobaea L. (Jakohs-Kreuzkraut) durch Herbizidanwendung im Herbst oder Frühjahr Auf Grünland, das mit Jakobs-Kreuzkraut verseucht war, wurde eine Reihe von Herbiziden im Oktober 1976 oder im Mai 1977 eingesetzt. Die Bekämpfung, gemessen am Rückgang blühender Pflanzen im Juli 1977, war mit alien Herbiziden äusserst zufriedenstellend. Die Spritzung im Oktober ergab für S. jaco baea einen Bekämpfungsgrad von 99% und wird für Grünland, das für Silagegewinnung genutzt wird, vorläufig empfohlen.     

Esophageal Replacement in the Dog by Microvascular Colon Transfer

An orthotopic colon graft based on the middle colic artery and vein was implanted with microvascular technique and a stapling instrument in five dogs. The grafts were successful in four dogs. A similar colon autograft was used to replace the entire thoracic esophagus in five dogs. The recipient vessels were the left carotid artery and left external jugular vein. Four of the grafts failed because of kinking and thrombosis of the arterial supply (2 dogs) or the venous outflow (2 dogs). One graft, which had a viable vascular supply, developed a severe leak at the colon-to-stomach anastomosis, and the dog was euthanatized on day 3. The recipient vascular pedicle was modified and used successfully to replace a portion of the cervical esophagus in three dogs. The grafts survived, the dogs could swallow liquids and semisolid food well, and, at necropsy after 4 weeks, the anastomotic sites were well healed. The graft sites contained essentially normal colon mucosa.     

Mechanical Testing and Evaluation of Eight Synthetic Casting Materials

Eight synthetic casting materials were evaluated with respect to tensile and fatigue strengths, exothermicity (evolution of heat during polymerization), permeability (porosity), radiolucency, and cost. Strength determination for a five-layer sample included measurement of the ultimate load at which a material failed, the ability to absorb energy, and the stiffness a material possessed after application of a cyclic stress. Results indicated that Vet Cast was superior with respect to tensile and fatigue strengths. The exothermic reaction associated with the "curing" or polymerization process was evaluated and not considered excessive although Ultra Cast attained a temperature of 48.0°C and was uncomfortable to handle during application. Permeability was determined. Delta Lite and Hexcelite NS were the most permeable materials and dried more rapidly and thoroughly after immersion than the other casting materials. Hexcelite NS was considered the least radiolucent material and was the most expensive material studied. Each of the synthetic casting materials demonstrated superiority in one or more of the categories tested. No one product demonstrated consistent superiority in criteria appropriate for clinical application.