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1.
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   
2.
Three serological methods, the Rose-Bengal test (RBT), the complement-fixation test (CFT) and an indirect enzyme-linked immunosorbent assay (I-ELISA) were compared for the detection of Brucella-infected animals in unvaccinated cattle herds in Eritrea. In this study, 71 herds first were classified as positive or negative for Brucella infection on the basis of at least one animal being seropositive by RBT and CFT. All the 159 RBT-positive samples from the 26 seropositive herds and 214 RBT-negative samples randomly selected from the seropositive herds and from the 45 negative herds were tested further by CFT and I-ELISA. Using the ELISA titer as main predictor, and incorporating the RBT results, a logistic model was built to predict the CFT-negative or -positive status of individual sera and to estimate sensitivity and specificity. Whilst the ELISA titers (< or =20) accurately predicted all the negative sera in herds that were also negative by the CFT, the number of seropositive animals was higher by ELISA in herds that had positive animals. Serum samples which give higher degrees of agglutination with the RBT need not be re-tested with CFT; consideration of the seropositive status of a herd should be taken into consideration on defining the cut-off optical density readings for ELISA.  相似文献   
3.
Susceptibility to acephate, methomyl, and permethrin was determined with laboratory bioassays for adults of greenhouse whitefly, Trialeurodes vaporariorum Westwood, from 12 to 14 sites in Hawaii. Comparisons at LC50 showed up to 42-fold resistance to acephate, 36-fold resistance to methomyl, and 8-fold resistance to permethrin. Higher levels of resistance to acephate and methomyl than to permethrin are consistent with greater use of organophosphates and carbamates than pyrethroids by growers. Insecticide use varied from 1 to 98 insecticide sprays per site per season. Significant positive associations between LC50 for each insecticide and frequency of application of the same insecticide were found across sites. This finding suggests that local variation in insecticide use was an important cause of variation in susceptibility.  相似文献   
4.
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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The essential oils of four medicinal plants belonging to Lamiaceae were explored for phytonematode control. The four oils inhibited (P<0.05) nematode motility butMentba spicata was generally more effective in reducing the numbers of active nematodes followed byThymus vulgaris, Majorana bortensis andMentba longifolia. The main corresponding compound of each oil, determined by GLC analysis, was carvone (58.14%), P-cymene (40.5%), terpinen-4-ol (41.6%) and carvone (70.36%). Soil stages of the reniform nematode were more affected by the oil than those of the ring and lance nematodes. When transferred to water, the total nematodes that regained their activeness ranged from 12% forT. vulgaris to 60% forM. longifolia. The four 0.1 oil solutions inhibited more than to about 3.5% at the control. The content of oxygenated compounds in these oils ranged from 45.79% to 96.5% and may be partially responsible for the nematicidal effects.  相似文献   
7.
The aim of this study was to test the applicability of electrical stimulation of lumbar spinal nerve roots and obtain normative electrical root stimulation (ERS) data for L7 nerve root and sciatic nerve in dogs. For that purpose ERS and sciatic nerve stimulations were performed consecutively, in totally 40 healthy dogs. ERS was applied in the L7/S1 intervertebral space via monopolar needle electrodes. Muscle responses were recorded from the gastrocnemius muscles on the left and right hind limbs. Sciatic nerve stimulation was performed at the greater trochanter level on the left hind limb, with records obtained from the left gastrocnemius muscle. Mean root latencies of the left and right side were 5.22?±?0.49 ms and 5.29?±?0.53 ms, respectively. There was no significant difference in root latency between the right and left sides. The mean terminal latency was 3.82?±?0.46 ms. The proximal motor nerve conduction velocity of the sciatic nerve was 63.15?±?3.43 m/s. The results of this study show that ERS provides objective data about the integrity of lumbar spinal nerve roots by evaluating the entire population of motor fibres and total length of the motor axon in dogs. ERS can be considered a useful diagnostic method for confirmation of diagnoses of lumbosacral diseases.  相似文献   
8.
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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Increasing consumer demands for indigenous, non-sprayed with pesticides and less-known or “forgotten” fruits necessitate knowledge on their breeding, cultivation, biochemical content, harvesting and marketing. Anatolia is rich for wild edible fruit species and barberry is abundant throughout Anatolia. The aim of this study was to determine some important physicochemical characteristics, bioactive content and antioxidant capacity of fruits from nineteen promising barberry (Berberis vulgaris L.) genotypes grown in the Coruh valley, Northeastern Anatolia. The results indicated genotype-specific differences for most of the physicochemical characteristics, antioxidant capacity and the content of some bioactive compounds. Fruit mass ranged from 0.073 (‘Coruh-7’) to 0.267 g (‘Coruh-11’). Total phenolic content ranged from 2532 (‘Coruh-’) to 3719 mg GAE per liter fruit juice (‘Coruh-11’). The genotype ‘Coruh-12’ had the highest total monomeric anthocyanin content (1004 mg per liter fruit juice) as cyanidin-3-glucoside. The highest total antioxidant capacity was observed in fruits of ‘Coruh-8’ and ‘Coruh-9’ genotypes with all three antioxidant-determining methods. We conclude that the barberry fruits represent a good source of bioactive phytochemicals because of their high phenolic and anthocyanin contents.  相似文献   
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