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121.
As a result of anatomic and physiologic differences, draft breeds may be at greater risk of developing anesthetic complications. The aim of the study was to evaluate and compare anesthetic management of draft (DR) and light (LT) horses. A case‐matched retrospective study of 371 clinical case records of DR (124 cases) and LT (247 cases) horses presented for general anesthesia between 1991 and 1998 was performed. Data were tabulated and comparisons were made using Student's t‐test (significance p < 0.05). Prior to induction, there were significant differences in mean body weight, rectal temperature, PCV, RBC, and serum TP concentration between DR and LT breeds. There were differences in mean doses of pre‐operative butorphanol (LT 21 µg kg?1; DR 17 µg kg?1), induction guaifenesin (LT 99 mg kg?1; DR 88 mg kg?1), and intraoperative ketamine (LT 0.35 mg kg?1; DR 0.56 mg kg?1) required. There were no significant differences in the mean doses of pre‐operative xylazine, detomidine, or induction barbiturate administered. The mean, average, and maximum concentrations of inspired halothane were significantly higher for DR than for LT horses. Draft horses received 33% less intraoperative IV fluids (8.2 mL kg?1 hour?1) than LT horses. Mean anesthetic duration, time to extubation, and standing recovery were not significantly different. Induction complications were not reported for either group. Rates of occurrence of intraoperative bradycardia, hypercarbia, hypoxemia, and metabolic acidosis (SBE, TCO2, and bicarbonate concentration) did not differ significantly. Average MAP was greater in DR horses, but neither the degree nor the mean duration of hypotension differed between DR and LT horses. Mean PaO2 was significantly lower in DR (246 mm Hg, 32.8 kPa) than in LT (305 mm Hg, 40.7 kPa) breeds. Draft horses were at greater relative risk of hypoventilation than LT horses. The greater MAP and requirement for halothane and intraoperative ketamine may indicate problems in achieving and maintaining a surgical plane of anesthesia. Draft horses may be at a greater risk of ventilation–perfusion mismatching.  相似文献   
122.
Erysipelothrix rhusiopathiae is a facultative, non-spore-forming, non-acid-fast, small, Gram-positive bacillus. The organism was first established as a human pathogen late in the nineteenth century. Three forms of human disease have been recognised since then. These include a localised cutaneous lesion form, erysipeloid, a generalised cutaneous form and a septicaemic form often associated with endocarditis. The organism is ubiquitous and able to persist for a long period of time in the environment, including marine locations. It is a pathogen or a commensal in a wide variety of wild and domestic animals, birds and fish. Swine erysipelas caused by E. rhusiopathiae is the disease of greatest prevalence and economic importance. Diseases in other animals include erysipelas of farmed turkeys, chickens, ducks and emus, and polyarthritis in sheep and lambs. Infection due to E. rhusiopathiae in humans is occupationally related, principally occurring as a result of contact with contaminated animals, their products or wastes, or soil. Erysipeloid is the most common form of infections in humans. While it has been suggested that the incidence of human infection could be declining due to technological advances in animal industries, infection still occurs in specific environments. Additionally, infection by the organism is possibly under-diagnosed due to the resemblance it bears to other infections, and problems encountered in isolation and identification. Various virulence factors have been suggested as being involved in the pathogenicity of E. rhusiopathiae. The presence of a hyaluronidase and neuraminidase has been recognised, and it was shown that neuraminidase plays a significant role in bacterial attachment and subsequent invasion into host cells. The role of hyaluronidase in the disease process is controversial. The presence of a heat labile capsule has been reported as important in virulence. Control of animal disease by sound husbandry, herd management, good sanitation and immunization procedures is recommended.  相似文献   
123.
Sweet sorghum (Sorghum bicolor (L.) Moench) is an annual crop currently being investigated for biofuel production in the arid southwest United States (U.S.). Sweet sorghum is an ideal candidate because it can be grown under reduced inputs (water, fertilizer) and responds more efficiently to stresses than traditional crops. Many varieties have been bred for high sugar, syrup, and forage production, but much biodiversity still remains to be utilized.Studies performed in 2006 and 2007 found that high biomass and percent juice extracted were the best predictors of potential ethanol yield per area. This investigation was undertaken to determine what effects planting dates have on overall sugar and predicted ethanol yields.Four varieties (Dale, M81E, Theis, and Topper) were planted in April, May, June, and July of 2008. They were harvested at physiological maturity, with dates ranging from August 26 to December 2. Biomass, juice weight, and Brix of the juice were recorded in the field. Samples were analyzed in the laboratory by High Performance Liquid Chromatography (HPLC) for fructose, glucose, and sucrose.Theoretical ethanol yields were calculated based on biomass, juice weight, and percent sugar. These were compared to actual yields obtained from laboratory-scale fermentations of the harvested juice, which ranged from 7.4% to 11.2% (58.1-88.6 g L−1). Since our predictive model uses the maximum conversion rate of sugar to ethanol and this was not reached in the lab, the predicted yields were always higher than the actual yields. However, the model can be a useful tool for estimating ethanol yield per area.Total sugars and predicted ethanol production were influenced by planting date, but the degree of the effects depended on the cultivar planted. Overall a May planting date at this location is preferable due to consistently higher values for the yield components analyzed, and Theis is not recommended due to its high susceptibility to heat. Sweet sorghum juice has been successfully fermented into ethanol, which indicates this crop may be able to play a transitory role in the emerging biofuel market.  相似文献   
124.
The scanning multichannel microwave radiometer results for the Gulf of Alaska Seasat Experiment Workshop are quite encouraging, especially in view of the immaturity of the data-processing algorithms. For open ocean, rain-free cells of highest-quality surface truth wind determinations exhibit standard deviations of 3 meters per second about a bias of 1.5 meters per second. The sea-surface temperature shows a standard deviation of approximately 1.5 degrees C about a bias of 3 degrees to 5 degrees C under a variety of changing meteorological conditions.  相似文献   
125.
The pike silverside has high aquaculture potential despite its slow growth. In this study, thyroxine (T4) concentrations (0.13, 1.3 and 13 nM), a control with no hormonal supplement and a negative control containing 4.5 mM methimazole (MMI) were tested to evaluate the growth of this species. Juveniles (0.2 g) were exposed by immersion to these treatments for 8 h every second day for 120 days, and growth evaluations were performed monthly over the entire trial period. In addition, tissue samples from each treatment group were assayed for triiodothyronine (T3) and deiodinase type 2 (D2) activity . The survival rates in all T4 groups were high, and a significant increase in growth was observed (average of 58%). The MMI treatment caused an increase in mortality and a reduction in the final body weight compared with the control. T4 administration did not affect the tissue levels of T3, and it decreased muscular D2 activity only after 30 days of exposure. These results demonstrated that low concentrations of T4 in the culture environment could improve the growth of this species without affecting tissue hormone levels. The technique may have useful applications for early‐stage aquaculture of this and other economically important species.  相似文献   
126.
A new pressure sensitive capsule for monitoring rumen activity has been developed. Surgery on the animal is not required for introducing the unit because it is small enough to be placed in the rumen using a stomach tube. The unit will transmit for several weeks and uses an inexpensive, commercially available pressure transducer as a sensor.  相似文献   
127.
A study comparing invasive versus oscillometric techniques for the measurement of arterial blood pressure was carried out in 4 anaesthetised sows undergoing laparoscopy. Regression analysis was used to determine the correlation coefficient. Bias was 19.2 for systolic, 20.6 for mean and 18.8 for diastolic. Both bias and precision showed a consistent underestimation of blood pressure values recorded by oscillometry. These results do not support the use of the oscillometric method when accurate figures for blood pressure are required in sows.  相似文献   
128.
The clinical features, radiographic findings, treatment, and outcome in 51 draft horses with osteochondritis dessicans (OCD) or subchondral cystic lesions (SC) are reported. Clydesdale and Percheron were the most commonly affected breeds, and affected animals represented only 5% of the hospital population of draft horses. Horses were most frequently affected in the tibiotarsal joints and 73% (24 of 33 cases) of the horses with tibiotarsal effusion were affected bilaterally. Osteochondritis dessicans of the distal intermediate ridge was the most common lesion found in the tibiotarsal joint. The stifle was also frequently affected; 87% (13 of 15 cases) of horses with femoropatellar OCD only were lame, and lesions were most commonly located on the lateral trochlear ridge. Sixteen cases were managed conservatively, 30 received surgery, and 5 were euthanized. Lameness, effusion, or both clinical signs resolved in more than 50% of surgically treated cases, but clinical signs improved in 30% of conservatively-managed cases.  相似文献   
129.
A 1.5-year-old female Bichon Frise dog was evaluated for a life-threatening hemorrhagic condition that occurred after ovariohysterectomy, requiring 4 whole-blood transfusions. A hemostatic profile, including activated clotting time (ACT), one-stage prothrombin time (OSPT), activated partial thromboplastin time (APTT), buccal mucosal bleeding time, and specific assays (heat-precipitation microhematocrit method and electroimmunoassay) for fibrinogen, were performed to investigate the coagulopathy. Clotting times for all tests having a fibrin clot endpoint (ACT, OSPT, APTT) and buccal mucosal bleeding time were prolonged. Plasma fibrinogen was not detected by heat-precipitation microhematocrit method or electroimmunoassay. Using the Ellis-Stransky method, a mixture of patient plasma and normal canine plasma with known fibrinogen content yielded substantially less than the calculated fibrinogen concentration, indicating the presence of an interfering substance. The interferent properties of the patient's plasma were retained following heat precipitation at 56 degrees C indicating the absence of a pyroglobulin or an abnormal fibrinogen molecule. Radial immunodiffusion assay using the patient's plasma and activated thrombin confirmed the existence of an inhibitor to the formation of fibrin. Western blot analysis using the patient's plasma identified an IgG antibody that reacted with the Beta- and gamma- but not the Alpha-subunits of canine fibrinogen. Antibody was detected in samples taken 8, 16, and 68 days after the surgery; peak titers were evident at day 16. These results supported a diagnosis of afibrinogenemia with a circulating antibody inhibitor to fibrin clot formation that developed secondary to blood transfusion.  相似文献   
130.
SUMMARY Bodyweight responses to subcutaneous injections of vitamin B12 and copper were investigated using Hereford calves in the southeast of South Australia, an area known to produce cobalt and copper deficient sheep. Calves were allocated to one of four groups: control; copper; vitamin B12; copper plus vitamin B12. Responses in bodyweight gain to vitamin B12, and to copper were obtained during the trial of one year. The results of biochemical analysis of blood, hair and faeces from calves and of dam's milk are reported. It is concluded that calves raised on cobalt-deficient pastures will require cobalt or vitamin B12 supplementation prior to weaning.  相似文献   
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