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41.
Tropical Animal Health and Production - Iranian buffalo plays a critical role in supplying a portion of the income and the necessities of the rural population. The first step to design a breeding...  相似文献   
42.
Aquaculture International - This study was performed to investigate the effects of dietary acetic acid, probiotic protexin, and their combination on growth performance, intestinal microbiota,...  相似文献   
43.
Nanofibers have a great potential for enzyme immobilization application due to their large surface area to volume ratio besides their porous structure. In this work, we produce polymethyl methacrylate (PMMA) nanofibers via electrospinning method in dimethylformamide (DMF) as solvent. Thereafter, we employ a chemical method on final PMMA nanofiberous web to covalently immobilize acetylcholinesterase (AChE) enzyme on membrane surface. Morphology and tensile properties of nanofibers are studied as first steps of characterization to make sure of obtaining a properly stable membrane for enzyme carrying application. Thereafter, the stability and activity of immobilized enzymes as two main characteristic parameters are tested and reported for different applications such as biosensor manufacturing.  相似文献   
44.
The Arasbaran Protected Area is an important but little studied nature reserve in NW Iran. In the past habitat heterogeneity and biodiversity have been threatened by over-exploitation; in the future depopulation may lead to partial abandonment. The soil seed bank was examined to see whether there are sufficient species represented as persistent seeds to reconstitute the vegetation in the event of habitat deterioration. There were differences between seed banks from different soils and vegetation types but essentially all soil seed banks contained few species and low densities of seed. Moreover, the species in the seed bank were unrepresentative of the vegetation. During future periods of changing land use it will be important to maintain the existing vegetation. There are however indications of successful recent conservation management. Annuals are abundant in the woodland seed bank but absent from the vegetation. The forest is recovering from the disturbance of collecting fire-wood.  相似文献   
45.
Tropical Animal Health and Production - The aim of this study was to determine the optimum carcass weight for meat quality and fatty acid composition in fat-tailed Chall lambs. Thirty lambs (15...  相似文献   
46.
The current study was designed to investigate the effect of idebenone (Id), an antioxidant on ram semen quality. Semen samples were collected, pooled and diluted in a Tris‐based extender supplemented with 0, 1, 2, 4 and 8 µM idebenone. Computer‐assisted sperm analysis was used to evaluate spermatozoa kinematics. Sperm viability and membrane functionality were assessed respectively, by eosin‐nigrosin staining and HOS test. Biochemical assays were carried out to measure different metabolites in spermatozoa and medium at 0, 24, 48 and 72 hr. Total and forward progressive motility were greater in 1, 2 and 4 µM idebenone treated groups compared to control at 24, 48 and 72 hr time points (p < 0.05). Semen supplementation with Id significantly increased viability and functionality of spermatozoa membrane during storage (p < 0.05). Lower amounts of lipid hydroperoxides in medium and spermatozoa were observed in Id‐treated groups compared to control one at 24 and 48 hr of storage (p < 0.05). Medium and spermatozoa amounts of malondialdehyde and nitric oxide were less in Id 4 µM group compared to the control at 72 hr (p < 0.05). Total antioxidant capacity values and superoxide dismutase activity of spermatozoa and medium were greater in 2 and 4 µM idebenone treated groups in comparison with the control at 72 hr (p < 0.05). Results of the current study indicated that ram semen supplementation with Id at 4 µM level improved quality by ameliorating nitrosative and peroxidative stress, hence could be considered as an antioxidant additive during storage at 4°C.  相似文献   
47.
The objective of this study was to determine the effects of fish oil replacement with dietary vegetable oils on growth performance, chemical composition and fatty acids profiles in fillets of farmed Caspian great sturgeon juveniles Huso huso (26.97 ± 0.49 g). Five isonitrogenous and isolipidic diets were formulated, containing 10 % of added oil. The diet with 100 % kilka fish oil (Caspian tyulka, Clupeonella caspia) was the control. Fish oil was substituted by 50 % of vegetable oils consisting of an equal share of sunflower and soybean oils (diet A), sunflower and canola oils (diet B) and soybean and canola oils (diet C). In diet D, 100 % of fish oil was replaced with vegetable oil (1:1:1 ratio of sunflower oil, soybean oil and canola oil). Significant differences (P > 0.05) were not detected during 60 days feeding trial in final body weight, weight gain, condition factor, specific growth rate, feed conversion rate, protein efficiency ratio and the chemical composition of fillet (crude protein, crude lipid, moisture and ash). Generally, the fatty acids composition of fish fillets was reflective of the dietary lipid sources. These results indicate the feasibility of substituting fish oils with the mixture of vegetable oils in diets of juvenile H. huso without negative influence on growth providing optimum ratios of n-3/n-6 and n-3/18:1n-9 is met in the diet.  相似文献   
48.
The objective of this study was to estimate heritability and genetic correlations between the liabilities of clinical mastitis (CM), milk fever (MF), metritis (MET), and retained placenta (RP) within the first three lactations of Holstein dairy cows. The records of 57,301 dairy cows from 20 large dairy herds in Iran between January 2005 and June 2009 were analysed with univariate and bivariate threshold animal models, using Gibbs sampling methodology. The final model included the fixed class effects of herd-year, season of calving, parity of dam, the linear covariate effect of age at calving, and the random direct genetic effect of animal. Posterior means of heritability for liabilities in first, second, and third lactations were 0.06, 0.08, and 0.09, respectively, for CM; 0.10, 0.12, and 0.11, respectively, for MF; 0.09, 0.07, and 0.10, respectively, for MET, and 0.07, 0.08, and 0.08, respectively, for RP. Posterior means of genetic correlations between disease liabilities were low or moderate (from −0.01 to 0.26). The results of this study indicated the importance of health traits for considering in the selection index of Iranian Holstein dairy cows.  相似文献   
49.
Replacement of olive pomace (OP) with wheat flour in diet was studied in diet of yearling Siberian sturgeon (Acipenser baerii). Fish (165 ± 6.8 g) were randomly allocated to 15 fibreglass tanks (15 fish/tank, in triplicate). Fish were assigned to one of five dietary treatments at 19.1 ± 1.5°C for 8 weeks: control diet (crude protein and crude lipid at 514.6 and 188 g/kg, respectively) and four experimental diets with 20, 50, 75 and 100 g/kg OP to replace wheat flour in the experimental diets. No significant difference was observed in the final weight, feed conversion ratio, specific growth rate, hepatosomatic index, viscera‐somatic index and survival rate among the treatments (p > 0.05). No change was seen in digestibility of protein and lipid in diets containing 20 g/kg and 50 g/kg OP compared to control group, while these values decreased with increasing in OP above 50 g/kg. Digestibility of dry matter and gross energy among the treatments demonstrated no significant difference (p > 0.05). Polyunsaturated fatty acids, especially C22:6n3 (DHA), in the muscle of the fish fed 75 g/kg and 100 g/kg OP in diets were significantly higher than control group (p < 0.05). These data show that OP could be recommended as a substitute for wheat flour in diet of S. sturgeon but its utilization for other species warranted future works.  相似文献   
50.
Single-walled carbon nanotubes, both before (SWNTs) and after treatment (t-SWNTs) with acidified ammonium persulfate, were successfully used to adsorb bisphenol A (BPA) and 17??-estradiol (E2) from aqueous systems. The surface characteristics of the SWNTs and t-SWNTs were analyzed by measuring their surface charge and by imaging their morphological properties through transmission electron microscopy. The extent of defects on the SWNT scaffold generated through acid etching was analyzed by Raman spectroscopy. A total of 19.4, 15.4, and 14.3?mg/g of BPA was adsorbed on SWNTs, while a total of 8.0, 6.4, and 5.1?mg/g was adsorbed on t-SWNTs with a 72-h contact time at 280, 295, and 315?K, respectively. A significantly high fraction of E2 (27.2?mg/g) was absorbed by both SWNTs and t-SWNTs, as compared to BPA. The adsorption kinetics was analyzed using a pseudo-second-order model. Sorption experiments showed that t-SWNTs adsorbed less than half as much BPA as SWNTs, but their E2 adsorption was similar. The sorption mechanism was investigated by performing molecular-level calculations. Adsorption energies calculated using density functional theory show preferential sorption of E2 to SWNTs and graphene (?26.2?kcal/mol on SWNT and ?34.1?kcal/mol on graphene) compared to BPA (?17.1?kcal/mol on SWNT and ?22.5?kcal/mol on graphene), which were consistent with the experimental findings. Thus, ab initio calculations can mechanistically explain the adsorption differences of BPA and E2 on SWNTs.  相似文献   
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