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Haematological and biochemical investigations were performed on 14 koalas with uncomplicated cystitis, 8 with complicated cystitis, 8 with conjunctivitis, 8 with lymphosarcoma, and 14 with miscellaneous diseases. Changes were limited and inconsistent in individual koalas with uncomplicated cystitis and conjunctivitis. In contrast, individual koalas with complicated cystitis were more likely to have anaemia, leukocytosis due to neutrophilia, hypoproteinaemia due to hypoalbuminaemia, and azotaemia due to elevated urea concentration. Although these changes were non-specific they did allow assessment of prognosis for survival and response to treatment. Koalas with lymphosarcoma were invariably anaemic, leukaemic, azotaemic and hypoalbuminaemic. Elevated enzymes (aspartate transaminase [AST]. lactate dehydrogenase [LD] and gamma glutamyl transferase [GGT]) were more common in koalas with lymphosarcoma. Koalas affected by miscellaneous conditions showed variable changes but once again anaemia, leukocytosis, azotaemia, elevated AST and LD, and hypoalbuminaemia were not uncommon. On the basis of these findings a minimal profile is suggested for the investigation of sick koalas and would include haematocrit, total and differential leukocyte counts, urea, total protein and albumin concentrations and AST, GGT and LD activities.  相似文献   
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Ecophysiological simulation models provide a quantitative method to predict the effects of management practices, plant characteristics and environmental factors on crop and weed growth and competition. The INTERCOM interplant competition model was parameterised, calibrated by monoculture data for three cowpea (Vigna unguiculata) genotypes that differed in growth habit, common sunflower (Helianthus annuus) and common purslane (Portulaca oleracea), and used to simulate competition of cowpea cover crops with sunflower or purslane. The simulation results were compared with observations from field competition experiments in 2003 and 2004. INTERCOM more accurately simulated actual field data for the competition of cowpea genotypes and sunflower than companion field experiments for the competition of cowpea and purslane. The validated simulation model of cowpea and sunflower at two densities was used to study the effects of cowpea growth habit on final biomass production of cowpea and sunflower. The model suggested that erect growth habit was more competitive than semi‐erect and prostrate growth habit, when cowpea genotypes were grown with sunflower. Cowpea leaf area distribution was important to higher cowpea biomass production, while cowpea height growth was important to reduce sunflower biomass. Our simulation approach is suggested as a method for crop breeders to gauge the likely success of selection for competitive crops before undertaking expensive long‐term breeding experiments.  相似文献   
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ABSTRACT Relationships between environmental factors and release of ascospores of Anisogramma anomala, the causal agent of eastern filbert blight, were examined in four European hazelnut (Corylus avellana) orchards during a 2-year period. In each orchard, Burkhard volumetric spore traps and automated weather-monitoring equipment were deployed for 12-week periods beginning at budbreak, when hazelnut becomes susceptible to infection. Ascospores of A. anomala were released when stromata on the surface of hazelnut branches were wet from rain but not from dew. Release of ascospores ceased after branch surfaces dried. The duration of free moisture on branch surfaces regulated the initiation and rate of ascospore release, but no significant effects of temperature, relative humidity, wind, or light on ascospore release were apparent. Most (>90%) ascospores were captured during precipitation events that exceeded 20 h in duration, which represented about 10% of the total precipitation events each season. Quantitative relationships between the hourly capture of A. anomala ascospores and hours since the beginning of a precipitation event were developed. With the onset of precipitation, the hourly rate of ascospore capture increased until the fifth hour of rain, remained relatively constant between the fifth and twelfth hours, and then declined gradually. During the 12-week spore-trapping periods, the likelihood and rates of ascospore release associated with precipitation were highest at budbreak and then declined through April and May until early June, when the reserve of ascospores in the perithecia was depleted. Large numbers of ascospores were captured in the volumetric spore traps, indicating that ascospores may be commonly dispersed long distances on air currents as well as locally by splash dispersal within the canopy, as reported previously. The results indicate that monitoring seasonal precipitation patterns may be useful for estimating the quantity and temporal distribution of airborne inoculum during the period that the host is susceptible to infection.  相似文献   
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Heart rate is a major factor influencing diagnostic image quality in computed tomographic coronary artery angiography (MDCT‐CA), with an ideal heart rate of 60–65 beats/min in humans. The purpose of this prospective study was to compare effects of two different clinically applicable anesthetic protocols on cardiovascular parameters and 64‐MDCT‐CA quality in 10 healthy dogs. Scan protocols and bolus volumes were standardized. Image evaluations were performed in random order by a board‐certified veterinary radiologist who was unaware of anesthetic protocols used. Heart rate during image acquisition did not differ between protocols (P = 1), with 80.6 ± 7.5 bpm for protocol A and 79.2 ± 14.2 bpm for protocol B. Mean blood pressure was significantly higher (P > 0.05) using protocol B (protocol A 62.9 ± 9.1 vs. protocol B 72.4 ± 15.9 mmHg). The R‐R intervals allowing for best depiction of individual coronary artery segments were found in the end diastolic period and varied between the 70% and 95% interval. Diagnostic quality was rated excellent, good, and moderate in the majority of the segments evaluated, with higher scores given for more proximal segments and lower for more distal segments, respectively. Blur was the most commonly observed artifact and mainly affected the distal segments. No significant differences were identified between the two protocols for optimal reconstruction interval, diagnostic quality and measured length individual segments, or proximal diameter of the coronary arteries (P = 1). Findings indicated that, when used with a standardized bolus volume, both of these anesthetic protocols yielded diagnostic quality coronary 64‐MDCT‐CA exams in healthy dogs.  相似文献   
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The aim of this study was to evaluate the reproductive performance of three parities of gilts treated or not treated with gonadotropin to induce puberty. Sixty gilts received 600 IU of equine chorionic gonadotropin (eCG) followed by 2.5 mg of porcine luteinizing hormone (LH) 72 h later. Fifty‐nine other gilts were exposed only to a mature boar for 15 min twice daily. Artificial insemination (AI) was performed at 0, 12 and 24 h after the detection of oestrus, and gestation was confirmed by ultrasound after 35 days. Sows were inseminated at the first post‐weaning oestrus. The total numbers of piglets born, piglets born alive, stillborn, mummified foetuses, as well as pregnancy and farrowing rates were evaluated for each of the three parities. Culling rates, farrowing intervals and weaning‐to‐oestrous intervals (WEI) were also analysed. Mean age at puberty and oestrous manifestation were not significantly different between treatments (p = 0.0639; 179.20 ± 17.52 compared with 173.96 ± 16.94, 91.66% compared with 94.92%) across the experimental period. However, females that underwent puberty induction showed modest increases both in the number of total pigs born and in the number of piglets born alive. In conclusion, puberty induction through exogenous gonadotropin administration in field conditions did not induce a more concentrated first oestrous manifestation, but trended to a modest increase in the number of pigs born alive in the first parity and a reduced culling rate during the first gestation.  相似文献   
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A 17-year-old Quarterhorse gelding with a clinical diagnosis of protein-losing enteropathy was submitted for necropsy following a 4-5-month duration of weight loss, decreased appetite, and hypoproteinemia. Gross findings included multiple 1-2-cm diameter ulcers on the luminal surfaces of the duodenum and ileum. Histologic examination revealed individual large, round cells infiltrating much of the mucosal epithelium of the duodenum, jejunum, ileum, and colon in addition to multifocal areas of ulceration. Similar round cells infiltrated Brunner's glands and expanded the submucosa beneath the foci of ulceration. Immunohistochemical staining indicated the round cell population was of T-lymphocyte origin. Several features of this equine neoplasm bear similarities to enteropathy-associated T-cell lymphoma in humans.  相似文献   
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