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The study was carried out to examine morphological and physiological effects of different levels of fat in compound extruded feed for carp. A 90 days experiment was performed in tanks with water flow 0.34 L min?1, stocked each with 29 specimens of carp, average weight 15.4 ± 4.2 g. The fish was fed 3 diets containing 38 % protein and 8, 12 or 16 % of fat (feed L8, L12, and L16, respectively). Body weight gain, specific growth rate, food conversion ratio, feed efficiency ratio, condition factor, liver and intestine histology and morphometry and some blood biochemical parameters were analysed. At the end of the experiment, a difference was established between the fish fed L8 feed compared to carp fed L12 and L16 feed for all growth parameters. For several other parameters, nuclear area of hepatocytes, nuclear/cytoplasm ratio, enterocytes height and intestinal folds’ length, a difference between carp fed feed L8 compared to feed L16 was found. The histological analysis revealed that normal structure of the liver and intestine prevailed, but changes were observed regardless of the diet type. In the hepatopancreas, more prominent changes were found around pancreatic tissue—particularly, increased number and size of adipocytes. Although blood biochemical parameters were within normal values, a difference between L8 and L16 diet-fed carp was found for plasma levels of triglycerides and total proteins. According to the results obtained in this study, the best results were achieved using a feed with 8 % fat.  相似文献   
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A 1-year-old castrated male cat was evaluated because of alopecia of approximately 4 to 5 months' duration as well as hyperactive behavior. It was later determined that the cat was ingesting valproic acid by eating food to which it had been added for daily administration to a child in the household who had cerebral palsy. The clinical signs slowly resolved after the source of valproic acid was removed. This emphasizes the sensitivity of cats to drugs that are commonly used in humans. It was not determined whether the clinical signs that developed in this cat were caused by an adverse reaction or from toxicosis as a result of prolonged hepatic elimination of valproic acid, which requires glucuronide metabolism for disposition. However, the cat recovered completely following removal of the drug and prevention of further exposure. This report emphasizes the importance of obtaining a careful and complete history from the owner regarding an animal and its environment. In the cat of this report, the owner had not considered the impact of the presence of the drug in the child's food.  相似文献   
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Earthworms, Eisenia fetida, were treated by surface exposure to the fungicide benomyl at various stages of posterior segmental regeneration. Teratogenic effects of benomyl were observed when worms were treated 7–11 days after amputation (i.e. during the normal period of segmental replication), but not during days 1–5, 13–17, or 19–23. Teratogenic effects included a reduction in the number of regenerated segments, an increased frequency of segmental groove anomalies, and a variety of monstrosities. The effects of benomyl treatment on the number of regenerated segments and frequency of anomalies were dose-dependent within a narrow concentration range (approximately 0.2–5.0 mg litre?1); at higher concentrations (e.g. 25 mg litre?1) teratogenic effects were less frequent because the onset of segmental delineation was delayed until well after exposure. Non-invasive electrophysiological recordings from treated worms indicated that functional integrity of giant nerve fibre conduction pathways was established in all anomalously regenerated tail segments, except in a two-tailed monstrosity. The evidence supports the hypothesis that these teratogenic effects derive from an antimitotic mode of action of benomyl on segmental regeneration.  相似文献   
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The erythrocyte sedimentation rate (ESR), white blood cell count (WBC), haematocrit (HCT) and platelet number (PLT) were quantified and compared with the acute phase proteins (APPs) in dogs naturally infected with Babesia canis and healthy dogs. Both groups were treated with imidocarb dipropionate on the day of admission and both groups were monitored for all parameters on the admission day and on the first, second, third, fourth and seventh days in order to determine the presence of an acute phase reaction, to assess the diagnostic value of these markers in uncomplicated canine babesiosis and to evaluate the use of APPs in treatment monitoring. It was demonstrated that an acute phase response occurs in dogs naturally infected with Babesia canis, with significant increases in the concentration of major acute phase proteins. The serum concentration of C-reactive protein (CRP), serum amyloid A (SAA) and the erythrocyte sedimentation rate (ESR) decreased daily after treatment and approached reference range values by the eighth day. PLT and haematocrit (HCT) increased daily after treatment and approached reference range values by the fourth day. WBC and haptoglobin increased after treatment and then decreased from the third and fourth days, respectively, to the eighth day. The diagnostic sensitivity of CRP, SAA and PLT was significantly higher compared to haptoglobin, ESR, HCT and the WBC count. CRP and SAA were of clinical use in monitoring the response to antibabesial treatment.  相似文献   
89.
Experiments were carried out to develop an optimal cryopreservation protocol for tench sperm by testing the fertilizing capacity and motility parameters including progressive motility, curvilinear velocity (VCL) and linearity (LIN) of cryopreserved sperm. Three experiments were designed to this aim: first experiment where we tested the effects of two extenders (sugar‐based Grayling and ion‐based Kurokura 180) and two cryoprotectants (DMSO and methanol) on fertilization and hatching success; second where we tested the effect of cryoprotectant type (methanol or DMSO) in different concentrations (5%, 10% and 15%) on fertilization and hatching success; and third where we tested the effect of two cryoprotectants (methanol and DMSO) on sperm motility parameters (progressive motility, VCL and LIN) after 4 h post‐thaw storage (4°C). Sperm prepared with the sugar‐based Grayling extender displayed better fertilization and hatching rates independently of the applied cryoprotectant most likely due to glucose present which acted as an external cryoprotectant. Concerning cryoprotectant concentrations, the use of 10% methanol yielded the highest fertilization (85 ± 15%) and hatching (80 ± 13%) rates, which were significantly higher than in all other groups. During the post‐thaw storage time, 5% methanol, 10% methanol and 5% DMSO groups had significantly higher motility parameters than other groups and we observed no significant decline in any of the parameters during the storage time. Overall, we found that a sugar‐based extender in combination with methanol as cryoprotectant is suitable for the cryopreservation of tench sperm and allows storage of cryopreserved sperm for up to 4 h post thaw.  相似文献   
90.
The magnetometer and electron reflectometer experiment on the Lunar Prospector spacecraft has obtained maps of lunar crustal magnetic fields and observed the interaction between the solar wind and regions of strong crustal magnetic fields at high selenographic latitude (30 degreesS to 80 degreesS) and low ( approximately 100 kilometers) altitude. Electron reflection maps of the regions antipodal to the Imbrium and Serenitatis impact basins, extending to 80 degreesS latitude, show that crustal magnetic fields fill most of the antipodal zones of those basins. This finding provides further evidence for the hypothesis that basin-forming impacts result in magnetization of the lunar crust at their antipodes. The crustal magnetic fields of the Imbrium antipode region are strong enough to deflect the solar wind and form a miniature (100 to several hundred kilometers across) magnetosphere, magnetosheath, and bow shock system.  相似文献   
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