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981.
Two horses were presented with lethargy, weight loss, anorexia, and swelling of the limbs and ventral body wall. One horse, a 12-month-old American Paso Fino colt, also had acute abdominal pain. The other horse, a seven-month-old Tennessee Walking Horse (TWH) filly passed diarrheic stools during the initial examination. Each horse had low serum protein, neutropenia, and a normal packed cell volume (3.2 g/dl, 1300 cells/ul, and 38%, respectively, for the colt, and 2.4 g/dl, 696 cells/ul, and 44%, respectively for the filly). After intravenously administering plasma, the colt's PCV dropped to 23%, and the filly's dropped to 30%. During exploratory surgery, 3.5 and 2.0 meters of thickened terminal small intestine were removed from the colt and filly respectively, and a jejunocecostomy performed. The results of histologic examination of resected intestine were consistent with a diagnosis of equine granulomatous enteritis (EGE). Both horses showed clinical improvement within two days after surgery. The colt developed a neutrophilia (20,500 cells/ul) within 24 hours of surgery. Serum protein concentrations remained stable and gradually elevated to normal or near normal values of 7.0 g/dl (colt) and 5.8 g/dl (filly) by two weeks. The colt was killed four months after surgery because of signs of abdominal pain. Postmortem examination revealed a small intestinal volvulus associated with an adhesion. The TWH filly remains clinically normal 13 months after surgery.  相似文献   
982.
Objective— To study the combined effects of intra-abdominal CO2 insufflation with changes in body position during laparoscopy in xylazine-ketamine-halothane anesthetized llamas. Study Design— Prospective, controlled study. Animals— Nine castrated, male llamas weighing 114 ± 23 kg, 3 to 13 years old. Methods— Three llamas (preliminary study [PS] group) were used to study the effect of right lateral, dorsal, and left lateral recumbency on gas exchange and acid-base status. The other six (experimental study [ES] group) were used to study the combined effects of changes in body position and CO2 insufflation to an intraabdominal pressure of 10 to 12 mm Hg. Heart rate, respiratory rate, and indirect arterial blood pressures (systolic [SAP], mean [MAP], and diastolic [DAP]) were recorded every 5 minutes during anesthesia. Arterial blood gases (PaO2 and PaCO2) and acid-base status (pHa and HCO3) were measured immediately after induction of anesthesia and before each change of position. Results— In the PS group, significant decreases in SAP, MAP and PaCO2 and increases in PaO2 and pHa were observed when the llamas were turned from right lateral to dorsal recumbency. Values for HCO-3 were lower than the postinduction values, but they remained unaffected by the changes in position. In the ES group, values for MAP were significantly lower when the llamas were placed in dorsal and left lateral recumbency than those observed during right lateral recumbency. Arterial O2 tension during right lateral recumbency was lower but returned to preinsufflation values when the llamas were placed in the dorsal position. All llamas recovered uneventfully within 30 minutes after termination of anesthesia. Conclusions— Insufflation of CO2 and changing body position induce minor and transient changes in cardiovascular and respiratory function. Clinical Relevance— Laparoscopy with mild intra-abdominal CO2 insufflation (10 to 12 mm Hg) can be used safely in spontaneously breathing llamas anesthetized with xylazine, ketamine, and halothane.  相似文献   
983.
Transected cranial cruciate ligaments in nine Holstein heifers were replaced with an autograft harvested from fascia on the medial surface of the gluteobiceps muscle and a connected segment of the lateral patellar ligament. There was minimal lameness at month 1, and all animals were sound by month 2. There was no evidence of degenerative joint disease in any stifles examined at necropsy on days 90, 120, or 365. Augmented healing of the severed cranial cruciate ligaments occurred in several animals. The mean failure strength of the cranial cruciate ligament replacements was 29.7% of the failure strength of the contralateral normal cranial cruciate ligament in four heifers. The technique was successful in eight of 13 bulls and cows with ruptured cranial cruciate ligaments. Animals treated successfully had significantly lower body weights than those with unsuccessful outcomes.  相似文献   
984.
Objective— To compare the biomechanical properties of five intramedullary (IM) pin fixation techniques for Salter-Harris type I fractures of the distal femur in dogs.
Study Design— Randomized, one-way factorial design composed of five treatment groups: (1) single IM pin, (2) dynamic IM crossed pins, (3) paired convergent pins, (4) crossed pins, and (5) crossed polyglycolic acid (PGA) rods.
Sample Population— Forty pairs of cadaver canine femurs.
Materials— One femur of each pair was manually fractured and subsequently repaired; the contralateral intact femur served as its control. Each femur was loaded in torsion until failure occurred and load-deformation curves were generated.
Results— The crossed-pin technique sustained the greatest load to failure (116.8%) followed by the paired convergent pins (104.8%), dynamic IM pins (90.6%), single IM pin (72.1%), and crossed PGA rods (71.9%). Statistically significant differences in strength at failure were detected between the crossed-pin and single IM pin and the crossed-pin and crossed PGA rod techniques. All fixation techniques underwent greater deformation (1.5 times as much) and had a lower stiffness (66% to 75%) compared with the intact controls; however, there was no significant difference between techniques. Failure in the paired convergent and crossed-pin techniques occurred by fracture of the bone; failure in the other techniques occurred by distraction at the fracture site.
Conclusion— The rotational stability of any of the fixation techniques appears to be primarily determined by the ability to prevent distraction and maintain interdigitation of the physis.
Clinical Relevance— When choosing a particular fixation technique for repair of a distal femoral physeal fracture, consideration should be given to the technique's relative biomechanical merits.  相似文献   
985.
From worldwide discussions about the limits of agriculture has arisen a powerful vision of sustainable development. Phrases like ‘limitation’, ‘sustainability’, ‘sufficient supply’, ‘fair distribution’ and ‘productivity of resources’ are no longer hindrances but guidelines for a fairer and safer world. ‘Nature's Concept' focuses on biological and ecological principles. On this basis, criteria of action have to be defined in order to determine long‐term economic consequences of agri‐production. The costs of destruction of natural resources, such as reduction of genetic resources, changes to the world climate and soil degradation, are inestimably large. The long‐term effects show the real substance of the agri‐shift and the demands on research. The solution for sustainable agriculture is more than ever a scientific development of ‘tools’ for a sensible management of resources. Gene technology may be an option to reduce the ecological risks of agriculture, especially those of devastating land use. For this purpose, new education programmes with international links and interventions by states are crucial in order to solve conflicts when short‐term interests interfere with long‐term ecological values. The international agri‐centres could have a further impact to guarantee access to new techniques for all countries. Thus agriculture could finally become a major pillar in a fair world order.  相似文献   
986.
Twenty-four chickens were randomly assigned to one of three treatments (ketamine, 30 mg/ kg; thiopental, 20 mg/kg; saline, 0.8 mL). Baseline data (heart rate, respiratory rate, systolic blood pressure, and cloacal temperature) were recorded before ulnar intraosseous cannulation and administration of drug treatment and for 30 minutes after administration. One investigator, unaware of the treatment administered, assessed the reaction to cannulation, number of attempts per cannulation, reaction to injection, time to induction and recovery, and quality of induction and recovery. Respiratory rate increased significantly (p < .05) from baseline after thiopental. Other parameters did not vary within groups or between groups. Most birds did not react or had a mild reaction to cannulation and injection, and on average fewer than two attempts were necessary. Quality of recovery was significantly (p < .05) better after thiopental. Time to recovery was significantly (p < .05) shorter after thiopental. No major histopathologic changes were noted in bone marrow samples from the injection site. This study demonstrates that the intraosseous route may be used to induce anesthesia in chickens, and that minimal changes in the variables studied were produced by ketamine and thiopental.  相似文献   
987.
OBJECTIVE: To compare drilling, tapping, and screw-insertion torque, force, and time for the 4.5-mm AO and 6.5-mm Acutrak Plus (AP) bone screws, and to compare the mechanical shear strength and stiffness of a simulated complete lateral condylar fracture of the equine third metacarpal bone (MC3) stabilized with either an AO or AP screw. STUDY DESIGN: In vitro biomechanical assessment of screw-insertion variables, and shear failure tests of a bone-screw-stabilized simulated lateral condylar fracture. SAMPLE POPULATION: Eight pairs of cadaveric equine MC3s METHODS: Metacarpi were placed in a fixture and centered on a biaxial load cell in a materials-testing system to measure torque, compressive force, and time for drilling, tapping, and screw insertion. Standardized simulated lateral condylar fractures were stabilized by either an AO or AP screw and tested in shear until failure. A paired t test was used to assess differences between screws, with significance set at P < .05. RESULTS: Insertion and mechanical shear testing variables were comparable for AO and AP insertion equipment and screws. CONCLUSION: The 6.5-mm tapered AP screw can be inserted in equine third metacarpal condyles and is mechanically comparable with the 4.5-mm AO screw for fixation of a simulated lateral condylar fracture. CLINICAL RELEVANCE: Considering the comparable mechanical behavior, the potential for less-persistent soft-tissue irritation with the headless design, and the ability to achieve interfragmentary compression by inserting the screw in one hole drilled perpendicular to the fracture plane, the 6.5-mm tapered AP screw may be an attractive alternative for repair of incomplete lateral condylar fractures in horses.  相似文献   
988.
989.
The in vitro susceptibilities of 128 isolates of east1+Escherichia coli from pre‐weaned and post‐weaned pigs with diarrhoea were tested with nine commonly used anti‐microbial agents by an agar dilution minimal inhibitory concentration (MIC) procedure according to National Committee for Clinical Laboratory Standards guidelines. For the isolates from pre‐weaned and post‐weaned pigs, most of them were susceptible to low concentrations (MIC90) of tetracycline (4 and 2 μg/ml), ceftiofur (2 and 2 μg/ml), and colistin (4 and 2 μg/ml). Marked resistance was found in others.  相似文献   
990.
This study assessed the effects of postoperative exercise and intra-articular polysulfated glycosaminoglycan (PSGAG) on the repair of osteochondral defects in the carpal joints of ponies. Eighteen ponies with normal carpi had osteochondral defects (mean dimensions 2.4 cm × 0.9 cm) created arthroscopically on the dorsal aspect of the distal articular surface of the radial carpal bone. The ponies were randomized (while balancing for age [range, 2 to 15 years; median, 5.0 years]) to two groups—nine ponies were exercised and nine were stall confined. Beginning at surgery, six ponies in each group received five weekly intra-articular injections of PSGAG (250 mg) in one joint and lactated Ringer's solution in the contralateral joint; the remaining three ponies in each group received lactated Ringer's solution in both joints. The incremental exercise schedule on a circular, rotating walker was begun six days after surgery and occurred twice daily, reaching a maximum of 0.7 miles of walking and 2.7 miles of trotting by the third postoperative month. The effects of treatment on the joint tissues were determined by weekly lameness examinations and measurement of the range of carpal joint motion, carpal radiographs at six and 17 weeks after surgery, synovial fluid analysis, and cytologic evaluation of alcohol-fixed synovial fluid specimens at weeks 1 through 4 and week 17, and histology of the synovial membrane. Ultrasound images of the carpi were acquired before operation and at weeks 1, 2, 4, 8, 10, 13, and 17. Ponies were euthanatized 17 weeks after surgery. Exercise, without medication, caused more lameness throughout the study compared with no exercise. Exercised, nonmedicated ponies had the greatest limitation to carpal flexion (more painful joints), and nonexercised, nonmedicated (control) ponies had the least limitation to flexion. Radiographic scores indicated that the exercised, nonmedicated ponies had significantly (p < .05) more signs of osteoarthritis than exercised, medicated and control ponies. Ultrasonographic measurements indicated that exercise, without medication, caused the greatest increase in combined measurement of the joint capsule thickness and synovial fluid accumulation at all postoperative times. Synovial lining cell numbers in the synovial fluid from exercised ponies were significantly (p < .05) higher than in nonexercised ponies at week 1, and this trend continued at weeks 4 and 17 (p < .1). There were significantly (p < .05) more morphologic abnormalities in the synovial lining cells from exercised than from nonexercised ponies at week 17. Medication with PSGAG enabled exercised carpal joints to be flexed significantly further from weeks 2 through 6 compared with nonmedicated joints. Medication significantly (p < .05) reduced the combined joint capsule and synovial fluid thickness at weeks 4, 8, and 13 compared with nonmedicated joints. On histologic examination, the synovial membrane matrix of exercised, medicated joints had significantly less chronic inflammatory changes than joints receiving other treatments. The authors concluded that this level of exercise was too intense when superimposed on large osteochondral defects in the carpus because it induced osteoarthritis. Polysutfated gtycosaminoglycan ameliorated the clinical signs of osteoarthritis in the exercised ponies. However, PSGAG was also associated with the formation of cartilage repair tissue that contained less type II relative to type I collagen compared with repair tissue from nonmedicated joints.  相似文献   
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