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21.
ObjectiveTo evaluate the clinical and physiological effects of epidural injection of ketamine in camels.Study designRandomized prospective study.AnimalsTen healthy immature male dromedary camels.MethodsKetamine was administered epidurally at doses of 1 and 2 mg kg?1 (five animals in each treatment). The drug was injected into the first intercoccygeal epidural space. Anti-nociception, sedation, ataxia, and effect on cardiopulmonary, rectal temperature and some selected haematological parameters were recorded at different intervals before (baseline) and after the drug administration. Data were analyzed by anova or U Mann–Whitney tests, as relevant and significance was taken as p < 0.05.ResultsEpidural ketamine at the 2 mg kg?1 dose produced complete anti-nociception in the tail, anus and perineum, whilst the 1 mg kg?1 dose produced complete anti-nociception only in the tail. Epidural ketamine resulted in mild to moderate sedation at the 1 mg kg?1 dose and deep sedation at the 2 mg kg?1 dose. Ataxia was observed in all test subjects and was severe, resulting in recumbency, in the 2 mg kg?1 group. Respiratory rate and rectal temperature did not change significantly after injection of either treatment. Following epidural injection of 2 mg kg?1 of ketamine, heart rate increased significantly from the pre-injection baseline of 55 ± 2 to 76 ± 4 (mean ± SD) beats minute?1, but after the lower dose changes were not significant. The only significant changes in measured haematologic parameters were decreases in total erythrocyte count at 45 minutes and total leukocyte count from 45–75 minutes, in the 2 mg kg?1 group.ConclusionEpidural ketamine injection was associated with caudal anti-nociception, sedation and ataxia in the dromedary camels; the intensity and duration of which was dose dependant.Clinical relevanceNeither of the doses of epidural ketamine injection in our study was applicable for standing surgical procedures in dromedary camels.  相似文献   
22.
Long-term effects of different levels of dietary vermicompost manure leachate powder (VCL) were investigated on the nauplii growth and survival, biochemical composition, total carotenoids, and reproductive performance of broodstock Artemia franciscana in laboratory cultures. The instar I nauplii were fed in five treatments including 100% of the microalga Dunaliella salina (Alg; control group, with a density of 18?×?106 cells mL?1) and mixtures of 75% Alg-25% VCL, 50% Alg-50% VCL, 25% Alg-75% VCL, and 100% VCL for 3 weeks. At maturity, 35 pairs (males and females) were individually isolated from each treatment and transferred to 50-mL falcon tubes in which the reproduction and longevity of females were monitored until mortality. Results showed that the total length of Artemia in the control, 75 Alg-25 VCL, and 50 Alg-50 VCL treatments was significantly different from the other groups at the end of the 2nd and 3rd weeks. The pre-puberty survival rate was severely affected by the increased dietary levels of VCL declining from 52% (control) to 6.7% (100 VCL). The adults’ body protein levels in the control and 75 Alg-25 VCL (54–57%) were similar, but both groups were significantly different from the other treatments. However, the lipid content (13.7–19.8%) and total carotenoids (36.5–47.7 μg mg?1) were significantly different between treatments. Many broodstocks’ reproductive characteristics were affected by the diet so that the total number of offspring in the control was markedly higher than the other groups. However, the number of offspring per brood revealed no differences between the control and 75 Alg-25 VCL treatment, but both were significantly dissimilar with the other groups. The interval between two successive brood productions detected in 100 VCL was almost double those in the other groups. The lifetimes of Artemia were not significantly different in the treatments received varied algal diets with the lowest lifespan in 100 VCL treatment. By increasing VCL to over 25%, the growth, survival, and particularly females’ reproductive performance decreased significantly so that Artemia had to be fed only up to 25% VCL (with 75% Alg). These findings indicate an inefficiency of VCL powder supply in long-term feeding to A. franciscana. Moreover, the use of only 25% VCL is apparently appropriate in small-scale laboratory cultures.  相似文献   
23.
Uncertainty and lack of information about the future make it difficult for shrimp farmers to develop and plan harvesting schedules. To do this effectively, farmers should be able to predict shrimp growth. A reliable prediction of growth and survival would also give farmers a better insight into future productivity and profitability. Linear and nonlinear regression models have been used to estimate growth of different types of animals. These models include theoretic guesses and hypotheses about the underlying laws that govern the system from which data are generated. Compared to such models, artificial neural networks (ANNs) make a few priori assumptions about the models and suited for predicting animal growth. This study evaluated the potential of an ANN as an alternative to regressions models for predicting shrimp growth. Empirical data were collected from 9 commercial shrimp farms in the Bushehr Province of Iran. The results showed that the ANN performed better compared to linear and nonlinear regression models for predicting the growth of farmed shrimp.  相似文献   
24.
Effects of graded dietary levels of fish meal (FM) replacement with meat and bone meal (MBM) with garlic powder (G) or without garlic powder (WG) garlic powder were investigated on growth, digestive enzymes, apparent digestibility, body composition and fatty acid profile of juvenile rainbow trout (Oncorynchus mykiss; 8.26 ± 1.10 g). A total of eight dietary treatments were evaluated: control with garlic powder (0 MBM+G), 250 MBM+G, 450 MBM+G, and 650 MBM+G (g MBM/kg diet; treatments with garlic powder; G treatments), control without garlic powder (0 MBM), 250 MBM, 450 MBM and 650 MBM (g MBM/kg diet; treatments without garlic powder; WG treatments). Our results demonstrated that increased dietary content of MBM impaired growth and production performance, body composition, digestive enzyme activity, tissue fatty acid profile and overall digestibility. Addition of garlic powder was able to correct fish performance, body composition, enzyme activity and digestibility to some extent. Dietary supply of garlic resulted in increased digestive enzyme activity improving fish performance. The current results indicated that fish fed 650 g MBM/kg feed exhibited impaired growth that could be attributed to reduce digestibility of protein, fat, energy and dry matter, PUFAs and n‐3 LC‐PUFAs in muscle. We suggest that 450 g FM per kilo feed can be successfully replaced with MBM supplemented with 30 g garlic powder per kilo feed without impairing fish performance and physiology, however distorting tissue fatty acid composition resulting in lesser levels of n‐3 LC‐PUFAs compared to the 0 MBM+G diet.  相似文献   
25.
Spirulina has been highlighted as a valuable complementary ingredient in aquafeeds due to its high protein and vitamin content, in addition to other nutritional benefits. To evaluate the effect of dietary spirulina inclusion in fish meal sparing (FMS) on juvenile Caspian brown trout as a slow‐growth fish, a complete randomized experimental design was developed with five treatments: 0% (control), 2% FMS (13.2 g/kg spirulina in diet), 4% FMS (26.4 g/kg spirulina in diet), 6% FMS (39.6 g/kg spirulina in diet) and 8% FMS (52.8 g/kg spirulina in diet). Six hundred juveniles (11.0 ± 1.0 g) were assigned to 15 experimental tanks. Although this fish is sensitive to diet composition, fish fed the 6% FMS and 8% FMS diets had a significantly higher weight gain rate (239.51% and 231.27%) and specific growth rate (1.74% bw per day and 1.71% bw per day) compared with those fed the control diet. Furthermore, 6% FMS and 8% FMS treatments had statistically higher protein efficiency (0.76 and 0.78), lipid efficiency (1.89 and 1.94) and statistically lower feed conversion ratio (2.47 and 2.41) compared with other treatments, respectively (p < 0.05). In terms of whole‐body composition, the higher amount of protein and lower content of lipid were observed in fish fed the 8% FMS diets as compared to control. Although no significant differences in ash and moisture content were observed, the highest protein deposition (157.3 g/kg) and the lowest lipid content (77 g/kg) in whole body were reported in fish fed 8% FMS diet. Based on the fillet fatty acid outcome, fish fed the 8% FMS diet had significantly higher saturated fatty acids (SFAs), C20:3n‐6, C18:3n‐3, polyunsaturated fatty acids (PUFAs) and total n‐3 fatty acids as compared to those fed the control diet (p < 0.05). Accordingly, increasing dietary spirulina content significantly enhanced the amount of these fatty acids in fish fillet. As regards of whole‐body amino acid profile, arginine and lysine in fish fed 6% FMS and 8% FMS diets were higher and lower than in those fed the control diet, respectively (p < 0.05). Fillet and skin colour parameters, such as luminosity, redness and yellowness, significantly increased with spirulina supplementation with the 8% FMS treatment displaying higher values than the control. In summary, according to our results, 8% FMS (52.8 g/kg spirulina in diet) treatment improved juvenile Caspian brown trout growth, carcass composition and pigmentation.  相似文献   
26.
This study investigated the effect of two lipid sources on reproduction performance and growth in pearl gourami. For this purpose, 180 fish (3.32 ± 0.25 g) were fed with three isoenergetic (19.80) and isonitrogenous diets (480 g/kg protein) including FO (80 g/kg fish oil), FS (40 g/kg fish oil and 40 g/kg soybean oil) and SO (80 g/kg soybean oil) for 10 weeks before maturation. At the end of the trial, there was no significant difference in weight gain, feed conversation ratio and body composition between fish fed FO and FS diets. Individuals fed dietary FO had significantly higher levels of n‐3 long‐chain polyunsaturated fatty acids in the muscle (130.5 g/kg lipid) and ovary (140.4 g/kg lipid) as compared with those fed SO diet (64.5, 103.6 g/kg, respectively) (p < .05). Feeding pearl gourami with FO and FS diets enhanced regarding absolute fecundity, relative fecundity, the fertilization rate, larvae total length and survival at 3 day posthatch (p < .05). Also, 17 beta‐estradiol in plasma of fish fed dietary FO (6.2 ng/L) was higher than those fed SO diet (1.7 ng/L) (p < .05). In conclusion, we suggest FS diet for broodstock nutrition of pearl gourami as a model for asynchronous multi‐batch spawning fish.  相似文献   
27.
Our aim was to evaluate the effects of fish oil feeding on sperm classical parameters, level of reactive oxygen spices (ROS), spermatozoa death incidence and in vitro fertilization (IVF) rate in rams. We randomly assigned nine rams, into two experimental groups (isoenergetic and isonitrogenous rations with constant level of vitamin E supplement): control (CTR; n = 5) and fish oil (FO; n = 4, 35 g/day/ram). Diets were fed for 70 days during the physiological breeding season. After a 21‐day dietary adaptation period, semen was collected weekly from each ram by an artificial vagina. Sperm classical parameters were determined by the computer‐assisted sperm analyzer system (CASA), and it was prepared for IVF process by swim‐up technique. These evaluations were performed during the first and last weeks of sampling. Intracellular ROS level and spermatozoa death incidence were detected by flow cytometry on a weekly basis after adaptation. Data were analysed with SPSS 15. The volume, concentration (3.6 and 2.7 × 109/ml) and sperm progressive motility (60 and 48%) were significantly improved in the FO group compared with the CTR (p < 0.05). A comparison of two‐cell stage embryos following IVF in the two groups showed a significantly higher fertilization rate in the FO group (56%) compared with the CTR (49%). Superoxide anion (O2?) rate was significantly lower (p < 0.05) at the third week of sampling in the FO. Although the H2O2 rate was numerically lower in the FO group compared with the CTR, this difference was not significant. In addition, apoptosis showed a significant difference in the third week of sampling (15 and 30% for FO and CTR, respectively; p < 0.05). Overall, adding fish oil to the ram diet not only improved sperm quality and IVF results, it also could reduce oxygen‐free radicals and the incidence of spermatozoa death.  相似文献   
28.
29.
Soil salinity presents a serious threat to crop production. The relatively poor tolerance to this stress agent exhibited by conventional crops incentivizes the search for alternative producers of food and forage in salinity-affected environments. Halophytes belonging to the genus Salicornia L. have been suggested as being able to provide both forage and edible seed oil. Here, a set of 14 Salicornia europaea L. accessions was investigated for their ability to produce seed oil and forage in response to a range of salt concentrations (100, 300 and 600 mM NaCl) in the water used for irrigation. Seed of the accessions was collected from diverse sites close to saline rivers and the sea in Iran. Salinity was shown to have a major effect on biomass yield, and on seed oil yield and composition. The ratio of unsaturated to saturated fatty acids in the seed oil was remarkably high. Forage yield was highest when irrigated with 300 mM NaCl for most of the accessions, while a level of 600 mM NaCl suited the production of seed oil.  相似文献   
30.
Aphelenchoides paraxui n. sp. is described and illustrated from bark samples of an oak tree (Quercus brantii L.) in Kermanshah province, western Iran. The new species is characterized by body length of 500–660 μm (females) and 630–665 μm (males), lip region set off from body contour, lateral fields with four lines, and total stylet 8–9 μm long with small basal swellings. The excretory pore is located ca one body diam. Posterior to metacorpus valve. The spicules are relatively large (29–33 μm in dorsal limb) with apex and rostrum rounded and well developed and the end of the dorsal limb clearly curved ventrad like a hook. The female tail is conical, the terminus having a complicated step-like projection, usually with many tiny nodular protuberances. Male tail bearing six (2 + 2 + 2) caudal papillae and a well-developed mucro. The new species belongs to the Group 2 category of Aphelenchoides species sensu Shahina (1996) in which eight known species among Group 2–4 sensu Shahina namely: A. arcticus, A. asteromucronatus, A. blastophthorus, A. lichenicola, A. saprophilus, A. seiachicus, A. silvester and A. xui, are the most closed species. Molecular analyses of the partial small subunit rDNA gene (SSU), D2/D3 expansion segments of the large subunit rDNA gene (LSU) and internal transcribed spacer (ITS) revealed this as a new species and supported the morphological results.  相似文献   
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