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81.
82.
Data from nine trials conducted from 1990 to 1998 in apple orchards in Nova Scotia and Quebec, Canada, were used to estimate the predator-prey selectivity of miticides and their potential compatibility with biological control of mites. The European red mite Panonychus ulmi (Koch) was the dominant and more harmful phytophagous species, followed by the apple rust mite, Aculus schlechtendali (Nalepa). Two predacious mites, the phytoseiid, Typhlodromus pyri Sheuten, and the stigmaeid, Zetzellia mali (Ewing), were often found in the orchards. We used one minus the ratio of mite-days in treated plots to those in the control plots as an index of population suppression and toxicity of the miticides. Miticides were then categorized into classes similar to those employed by the International Organization for Biological Control to rate pesticide toxicity to natural enemies of insect and mite pests. Selectivity of miticides was mostly based on toxicity to P ulmi, the major pest, versus toxicity to T pyri, the major predator, with some consideration of the two lesser species, A schlechtendali and Z mali. In most cases, our findings were in accord with other studies. Abamectin and clofentezine had favourable selectivity (more toxic to the two phytophagous mites than to T pyri). The higher recommended rate of pyridaben (450 g ha(-1)) and two rates of spirodiclofen (180 and 240 g ha(-1)) were neutral (equally toxic to pests and predators). The lower rate of pyridaben (216 g ha(-1)), dicofol, formetanate hydrochloride and propargite were unfavourably selective (more toxic to T pyri). A higher than recommended rate of pyridaben (2160 g ha(-1)) applied before bloom was disruptive--P ulmi-days after treatment were actually greater than with the untreated control. P ulmi resistance to dicofol and propargite were probable complicating factors in some of the orchard trials.  相似文献   
83.
Limited nutritional information exists on diets of free-ranging orangutans, Pongo abelii and P. pygmaeus. Although they are classified as frugivores, the chemical composition of their diet and their gastrointestinal anatomy suggest that they rely on fiber fermentation for a substantial portion of energy. However, the extent to which they can ferment fiber is not known. Continuous culture systems, inoculated with orangutan fecal bacteria, were established to determine the fiber-digesting capacity of orangutan hindgut microflora. The cultures received one of four treatments: soybean hulls, ground corncobs, corn starch, or no food. Neither dry matter nor neutral detergent fiber digestibilities differed significantly among treatments. However, neutral detergent fiber digestibilities were high for both the soybean hull (88.4%) and ground corncob (86.1%) treatments, indicating that the microflora had a strong fibrolytic capability. To determine whether the same fiber-degrading capacity occurred in vivo, two adult orangutans and one juvenile were fed four gel-matrix diets containing soybean hulls, ground corncobs, or ground primate biscuits. Neutral detergent fiber concentrations (dry matter basis) of the gel matrices were 52.9% with soybean hulls, 46.8% and 63.7% with ground corncobs, and 31.3% with ground primate biscuits. A fifth diet consisted of primate biscuits with 27.3% neutral detergent fiber (dry matter basis) and was considered the baseline diet. Neutral detergent fiber digestibility (74.5%) was greatest (P < 0.05) for the soybean hull gel diet and least (57.5% and 45.0%, respectively; P < 0.05) for the 63.7% neutral detergent fiber (dry matter basis) corncob gel diet and the baseline primate biscuit diet. Total volatile fatty acid concentrations in orangutan feces were not significantly different among diets; however, molar proportions of acetic, propionic, and butyric acid differed (P < 0.05) among diets. The results from both studies indicated that orangutans are capable of extensive fiber fermentation.  相似文献   
84.
Two mares were evaluated because of chronic uterine torsions of 2 and 4 weeks' duration; both were pyrectic, anemic, tachycardic, and anorectic, had signs of depression, and had an abnormal uterus and contents on transrectal examination. Both mares underwent cesarean section for lysis of adhesions from the uterus to the peritoneum, correction of the torsion, and ovariohysterectomy Both mares recovered with only minor complications and returned to be used as riding horses. Chronic uterine torsion should be considered in mares in late stages of gestation that have vague clinical signs and transrectal palpation findings that are unlike those described in typical cases of uterine torsion. Prognosis for life can be good after treatment by ventral midline celiotomy, cesarean section, correction of the torsion, and ovariohysterectomy.  相似文献   
85.
Questions about pathogenesis and therapy for Helicobacter infections in dogs could be answered with a simple, noninvasive, sensitive, and specific diagnostic test. We hypothesized that a fecal polymerase chain reaction (PCR) assay would detect Helicobacter and could be useful for assessing therapeutic responses. Paired gastric biopsies and fecal samples were obtained from 39 random source dogs (group 1). Gastric biopsies from each of these dogs had histologic evidence of gastric spiral bacteria, and paired gastric tissue and fecal samples produced a 375-base pair (bp) product when amplified by PCR with Helicobacter-specific primers. Specificity of the PCR product was confirmed by detection of expected 60-, 119-, and 196-bp products following Hinfl digestion. Direct sequencing of amplicons from paired PCR products from gastric biopsy and fecal samples from 8 group I dogs showed that gastric products had the highest homologies with known gastric Helicobacter species, whereas fecal products had the highest homologies with intestinal species. Healthy mixed-breed dogs (group II; n = 8) with histologically confirmed spiral bacteria infection were treated with a 21-day course of metronidazole, amoxicillin, and famotidine. Fecal samples were collected from group II dogs twice before and within 3 days of completion of treatment. The PCR results correctly identified 15/16 pretreatment samples as positive: 1 pretreatment sample was negative. PCR results identified 8/8 posttreatment samples as Helicobacter negative. Fecal PCR is a useful test for detecting Helicobacter infection in dogs. This assay may be useful as a screening test for infection and could be used to address questions relevant to pathogenesis and therapy.  相似文献   
86.
A retrospective study of the medical records of 33 horses was performed to determine the clinical and diagnostic abnormalities associated with temporohyoid osteoarthropathy. Data collected from medical records included signalment, presenting complaints, history, physical examination findings, laboratory data, results of diagnostic imaging studies, and treatments. Follow-up information was obtained from a review of case records; by telephone conversation with the owner, veterinarian, or trainer; or by both methods. Of 33 horses with temporohyoid osteoarthropathy, 29 presented with facial nerve (cranial nerve VII) deficits and 23 presented with vestibulocochlear nerve (cranial nerve VIII) deficits. Guttural pouch endoscopy was more reliable than radiography for diagnosis. Of horses with unilateral clinical signs, 22.6% actually had bilateral disease. Magnetic resonance imaging and computed tomography identified the lesions in all horses in which these tests were performed. Of 30 horses for which follow-up information was obtained, 20 (67%) were alive. Eight horses were euthanized and 1 died because of problems associated with temporohyoid osteoarthropathy. Nineteen of 20 surviving horses (95%) were considered by the owner or trainer to be suitable for athletic use. Twelve surviving horses (60%) had residual facial nerve deficits; 11 horses (55%) had residual vestibulocochlear nerve deficits. Horses with temporohyoid osteoarthropathy have a fair prognosis for return to some type of athletic function, but there is risk of acute death. The majority of horses would be expected to have some residual cranial nerve dysfunction, and it could take a year or longer for maximal improvement to occur.  相似文献   
87.
88.
Thirteen coagulation tests evaluating hemostatic and fibrinolytic indices and serum cytokine and plasma endotoxin concentrations were obtained in 34 foals with a positive sepsis score (septic group) and 46 age-matched healthy foals. Compared to healthy foals, the prothrombin, activated partial thromboplastin, and whole blood recalcification times were significantly longer in septic foals. The fibrinogen and fibrin degradation products concentrations, percent plasminogen, alpha-2 antiplasmin, and plasminogen activator inhibitor activities, and tumor necrosis factor and interleukin-6 activities were greater in septic foals. Protein C antigen and antithrombin III activity were significantly lower in septic foals. Blood cultures were positive for growth and endotoxin was detected in 19 of 29 and 15 of 30 septic foals, respectively. In septicemic foals with detectable endotoxin in the plasma, the prothrombin and activated partial thromboplastin times were significantly longer and the plasminogen and antithrombin III activities were significantly less than in septic foals in which endotoxin was not detected. Twenty-three of the 34 septic foals did not survive. Septic foals that did not survive were most likely to have a positive blood culture in which a gram-negative organism was isolated. Histopathologic evidence of hemorrhage was evident in 11 foals at postmortem examination and thrombosis was identified in 2 foals. The prothrombin time was significantly longer in foals that had multisite hemorrhage at postmortem examination. The results of this study indicate that clinically relevant alternations in hemostatic and fibrinolytic indices occur in neonatal foals with septicemia and that derangements can be correlated with the presence of endotoxin in plasma. Derangements in hemostatic or fibrinolytic indices were helpful in identification of septic foals with increased risk of coagulopathy, but were not helpful in predicting hemorrhage as compared to thrombus formation. Survival of septicemic foals was correlated with gram-negative bacteremia, but not with the presence of endotoxin or coagulopathy.  相似文献   
89.
90.
Objective— To compare short‐ and long‐term outcome and complications of chest wall reconstruction in dogs using autogenous, prosthetic, and composite autogenous–prosthetic techniques. Study Design— Historical cohort. Animals— Dogs (n=44) with spontaneous tumors arising from or involving the chest wall. Methods— Medical records were reviewed for dogs with rib and/or sternal tumors treated by chest wall resection and reconstruction. Signalment, preoperative clinical features, intraoperative findings and complications, reconstruction technique (autogenous muscle flap, prosthetic mesh, or composite autogenous–prosthetic technique), and short‐ (≤14 days) and long‐term (>14 days) postoperative complications were determined from the medical records and telephone contact with owners and referring veterinarians. Associations between chest wall reconstruction technique and postoperative complications were tested with Cox proportional hazards. Results— Chest wall defects were reconstructed with autogenous muscle flaps (29 dogs), prosthetic mesh (3), and a composite technique of prosthetic mesh and either autogenous muscle or omental pedicle flap (12). Early postoperative complications were recorded in 8 dogs (18.2%) and included seroma (5) and pleural effusion and peripheral edema (3). One dog had a late complication (2.3%) with a mesh‐related infection 767 days postoperatively. Overall, complications occurred in 10.3% of autogenous, 25.0% of composite, and 66.7% of prosthetic reconstructions. Chest wall reconstruction with Marlex mesh alone was associated with a significantly increased risk of postoperative complications compared with autogenous reconstruction (P=.027). Reconstruction of sternal defects (3), 2 of which were performed with Marlex mesh alone, was associated with a significantly increased risk of complications compared with lateral chest wall reconstructions (P=.037). Conclusions— Large chest wall defects can be reconstructed with autogenous and composite techniques, but prosthetic mesh should be covered with well‐vascularized autogenous muscle or omentum to decrease the risk of postoperative complications. Sternal defects should be reconstructed with rigid techniques. Clinical Relevance— Chest wall reconstruction with autogenous muscle flaps or a combination of autogenous techniques with prosthetic mesh is associated with a low rate of infection and other complications.  相似文献   
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