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1.
In ovo injection (IOI) of Naringin (N), flavanone was examined on post‐hatch blood biochemical parameters, antioxidant status and bone characteristics. Fertile eggs (n = 700) were distributed in seven groups with 100 eggs. On 14th and 17.5th days of incubation, four groups were injected using 15 or 30 mg active ingredient levels of naringin/0.5 ml saline/egg, low and high level, into amnion sac. Controls include sham (injected normal saline, 0.5 ml/egg on day 14 and 17.5th) and un‐injected group. IOI of high naringin and saline on 14th day of incubation resulted in lower hatchability and then higher mortality in last week of embryonic life. On day hatch, high levels of injected groups more body weight compared to the control. Chick length was increased at high levels of naringin on day 17.5th compared to control and saline injected. Quality traits of bones were improved in naringin‐injected groups compared to control. IOI of naringin influenced thyroid hormones on 14th day of incubation. Naringin groups influenced the Alkaline phosphatase (ALP), Calcium (Ca), superoxide dismutase (SOD), blood biochemical and lipids. Totally, amniotic IOI of naringin in last days of developing embryo may be useful for hatched chick, development of leg long bone or effect on biochemical metabolites by levels of flavanone that it needs more research.  相似文献   
2.
We investigated the distribution and frequency of damage to tree stands adjacent to low-volume roads according to the type of hillside materials involved(soil or rock) and hillside gradient in mountainous forests of northern Iran. A total of 80 plots were systematically and randomly sampled to record damaged trees(bending,crushing and wounding) by class of hillside gradient and materials at the edge of road. Tree wounding and crushing at rock slopes was significantly greater than at hillsides with a mix of clay soil(p \ 0.05). Damage on hillsides with slope gradients[45% were 2, 8.5 and 2.3 times more frequent than on hillsides with slope gradient\15% for bending, crushing and wounding, respectively. The damage distribution varied according by type and the most frequent damage was tree wounding(p \ 0.05). The damage distribution was measured at distances of 4, 5 and 8 m from the road fillslope for tree bending, crushing and wounding, respectively. Using hydraulic excavators and physical barriers(wooden obstruction and synthetic holder) during earthworks for road construction could reduce these damage.  相似文献   
3.
In this study, the effect of a vacuum impregnation (VI) process with pulsed electric field (PEF) pretreatment on fortification of whole potato with ferric pyrophosphate was investigated. The VI process and PEF pretreatment were optimized with respect to physicochemical attributes of PEF-VI-processed samples using response surface methodology (RSM). The results indicated that the iron content of VI-processed and PEF-VI-processed potatoes was increased about 126 and 457%, respectively, compared to unprocessed potatoes. A more intensive PEF pretreatment led to a higher cell disintegration, decrease in colour and textural parameters and also increase in components leakage from treated potato. Our study suggests that whole 180-g potatoes should be pretreated at 394 V/cm with 36 pulses and then treated at 3.5 kPa for 37 min in vacuum stage and 39 min restoration time in atmospheric stage to achieve the highest iron fortification and the lowest physicochemical changes during PEF-VI processing.  相似文献   
4.
This experiment was carried out to investigate the potential probiotics properties of Bacillus subtilis in protecting of juvenile freshwater prawn, Macrobrachium rosenbergii against Aeromonas hydrophila infection. A B. subtilis bacterium isolated from gut of juvenile prawns was added to the prawns feed at 108 cells g?1 feed. There were significant differences (P < 0.05) between B. subtilis-treated and control groups in growth and survival enhancement of juvenile prawns after 60 days of feeding trial. Sixty days after B. subtilis feeding trial, the prawns were challenged by bath exposure to A. hydrophila (107 cells mL?1) for 28 days. Four weeks after challenge, there was significant difference in the survival of prawns between B. subtilis-treated groups (88.33 %) and control groups (20.81 %; P < 0.05). In addition, the control groups had an unhealthy external appearance, while the treated groups, appeared healthy and normal. From this, it was concluded that the selected B. subtilis may be a promising probiotics for protection of prawns from A. hydrophila infection.  相似文献   
5.
Optimised pre-analytical methods for measuring the chemical properties of soil macro-organisms are needed. We tested the effects of ethanol immersion, freezer storage, and drying method on the reliability of estimates of key stoichiometric elements (carbon [C], nitrogen [N], phosphorus [P]) and abundances of 13C and 15N in samples of crickets (Acheta domestica), cockroaches (Nauphoeta cinerea) and mealworms (larval Tenebrio molitor). Ethanol immersion tended to increase A. domestica C and N, and reduced A. domestica P, relative to the reference treatment (deep freezing and oven drying). For N and P these effects were only present after 28-day ethanol immersion. Nauphoeta cinerea and T. molitor samples were generally unaffected by storage treatments, while δ13C and δ15N were not affected by any storage treatment for any species. Thus, five days of ethanol immersion may be acceptable prior to elemental and stoichiometric analyses of hard-bodied soil invertebrates in comparative studies.  相似文献   
6.
  • ? In this study, longitudinal specific modulus of elasticity along the grain (specific MOEL = MOEL/ρ) as well as radial and tangential shear moduli (G LR and (G LT ) of Populus Deltoides wood were examined in free flexural vibration in a free-free bar method, where end-cracks produced manually in LT plane along and parallel to annual rings in four different sizes.
  • ? The effects of four different crack sizes (0, 6, 12, and 18 cm) on elastic parameters of the bars were examined for their vibration properties based on Timoshenko bar equations, in order to find a procedure to make a confident choice of a clear specimen among the cracked ones, considering three initial modes of vibration.
  • ? Based on research findings, a significant correlation existed between radial and tangential shear moduli of the clear bars as G LR was approximately 15 percents higher than (G LT . After making the shortest crack sizes, however, this correlation entirely faded. Statistically for 6 cm crack, decreases in specific MOE L for measurement on the tangential impact were not significant though they were for longer cracks.
  • ? It was also revealed that in specimen under the study if longitudinal specific modulus of elasticity from both LR and LT flexural vibrations were almost equal and G LR was slightly larger than (G LT , the user could be confident enough to consider the specimen without severe longitudinal cracks.
  •   相似文献   
    7.
    In the present study, we examined the mortality rate, egg production, and clinical signs of quail experimentally infected with a field isolate of A/Chicken/Iran/339/02 (H9N2) avian influenza virus obtained from an infected commercial layer farm with severe morbidity and mortality. A total of 120 quail at 14 days old were randomly divided into four groups of vaccinated (B and C) and unvaccinated (A and D) birds. Vaccination was done on days 20 and 32, and viral inoculation of birds in groups C and D was then carried out on day 43. For evaluation of viral transmission, at 24 hr postinoculation additional unvaccinated birds were placed in direct contact with challenged birds. All the birds were evaluated for clinical signs, egg production, antibody production, viral titration in lung homogenates, and viral transmission following inoculation. All unvaccinated-challenged birds were infected and showed clinical signs, whereas the infection rate along with clinical signs of vaccinated-challenged birds reached 30%-40%. Although vaccination induced high antibody titers, reduction in food and water consumption was evident in this vaccinated-challenged group compared with the unchallenged control group. These results could indicate that inactivated vaccine did not fully prevent the infection, although it was capable of protecting birds against clinical signs and significantly decreased viral titers in lungs after intranasal challenge.  相似文献   
    8.
    1. Gelatin prepared from calf bones (GCB) is a novel source of high-quality protein and phosphorus. Its inclusion in broiler chicken diets may improve bone strength, plasma and digestive alkaline phosphatase activity (ALP), phosphorus digestibility and performance of broilers. Therefore, di-calcium phosphate in a corn-soy control diet was replaced with 12, 24, and 36 g/kg of GCB in a completely randomised design with four treatments of six replicates and 10 chicks in each pen. The trial lasted from 1 to 42 d of age.

    2. Body weight and feed intake were measured weekly. Plasma calcium and phosphorus concentration along with plasma and digestive ALP were assayed throughout the trial. Trypsin, α-amylase, lipase and total protease activity were assayed at 14 and 28 d of age. Tibia ash, calcium and phosphorus content and breaking strength were measured at 14, 28 and 42 d of age. Phosphorus digestibility was measured at 36 d of age.

    3. Body weight and feed intake showed no significant differences between controls and diets containing 12 and 36 g/kg GCB. Tibia ash and tibia length were increased by supplementation of GCB (P ≤ 0.001). Tibia calcium and phosphorus content were increased by GCB inclusion at 14 d of age (P ≤ 0.001). Digestive alkaline phosphatase activity was increased and trypsin activity was reduced by inclusion of GCB (P ≤ 0.001; P ≤ 0.004). α-amylase activity decreased by inclusion of 12 and 24 g/kg GCB, whereas an increase in α-amylase activity was observed by inclusion of 36 g/kg GCB (P ≤ 0.001). Supplementation of diets with GCB increased phosphorus digestibility (P ≤ 0.01) and suppressed ileum growth during the experimental period.

    4. Results of the current study showed that phosphorus from gelatin can greatly improve broiler bone characteristics and phosphorus digestibility and complete elimination of inorganic phosphate sources from broiler diets is feasible with inclusion of 36 g/kg high phosphorus gelatin.  相似文献   

    9.
    A biological assay was carried out to evaluate the impact of dietary tryptophan (TRP) in aflatoxin B1‐contaminated diets (AFB1‐D) on performance, blood parameters, immunity, meat quality and microbial populations of intestine in Japanese quails. Six experimental diets were formulated to include two levels of dietary TRP; 2.9 (moderate high: MH‐TRP) and 4.9 g/kg (excess: Ex‐TRP); and three levels of AFB1 (0.0, 2.5, and 5.0 mg/kg). Each experimental diet was fed to the one of the six groups of birds from 7 to 35 days of age in a completely randomized design with 2 × 3 factorial arrangement. Decrease in feed intake, body weight gain and gain:feed in birds fed 5.0 mg/kg AFB1‐D was restored to the control level by 4.9 g TRP/kg of the diet. The hepatic enzymes in blood were elevated in quails fed on AFB1‐D but attenuated by 4.9 g TRP/kg of the diet (Ex‐TRP; p ≤ .01). High serum uric acid in birds challenged with AFB1 significantly decreased by Ex‐TRP (p ≤ .01). The skin thickness to 2,4‐dinitro‐1‐chlorobenzene challenge suppressed by AFB1 but increased by Ex‐TRP diet (p ≤ .02). The AFB1 increased the malondialdehyde in meat, whereas TRP efficiently diminished malondialdehyde production (p ≤ .01). The greatest drip loss and pH in meat were observed in the birds fed 5.0 mg/kg AFB1‐D but Ex‐TRP augmented the adverse effects of AFB1 (p ≤ .01). The Ex‐TRP reduced the total microbial and Escherichia coli counts (p ≤ .01). The adverse effect of AFB1 on ileal Lactic acid bacteria was completely prevented by Ex‐TRP (p ≤ .03). This study showed that tryptophan supplementation could be considered as a powerful nutritional tool to ameliorate the adverse effects of AFB1 in growing quails.  相似文献   
    10.
    One hundred and ten clinical Escherichia coli isolates of serovar O157 (n = 102) and O26 (n = 8) were characterized for the presence of putative virulence genes by PCR. All but one of these isolates contained the eae gene. The EHEC-hly gene could be detected in all E. coli O157 and in 50% of E. coli O26 isolates. Forty-five (40.9%) of the 110 E. coli were positive for both stx(1) and stx(2) genes, 2 (1.8%) isolates were positive for stx(1) and 57 isolates (51.8%) were positive for stx(2) only. Among the 102 stx(2) positive isolates, 14 (13.7%) E. coli O157 contained also the stx(2c) variant gene. No other stx(2) variant was identified. Six clinical isolates (five E. coli O157:H7 and one E. coli O26) did not contain stx genes. Ten non-pathogenic E. coli isolates which were amplified as controls didn't contain any stx and eae gene but two of the ten strains contained the EHEC-hly gene. By their growth on chromogenic media, all but two of 50 E. coli O157 could be differentiated from eight E. coli O26 and 10 non-pathogenic E. coli. Sixty-one of the O157:H7 isolates were further subjected to pulsed-field gel electrophoresis (PFGE) which identified 49 distinguishable patterns. In five cases where contact infection among family members was suspected, indistinguishable PFGE patterns confirmed the epidemiological relatedness of the isolates. Moreover, two PFGE clusters were identified which comprised five and three strains, respectively. These findings indicate the occurrence of both family and diffuse outbreaks of E. coli O157 infections in Austria during recent years and demonstrate the need for molecular subtyping of these pathogens.  相似文献   
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