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1.
1. Soy isoflavones play a role in calcium and bone metabolism. Poor egg quality, skeletal abnormalities and architectural deterioration of bone tissue are common problems under hot climate conditions and with increased age in poultry. 2. In this study, we investigated the effects of soy isoflavone supplementation on egg production, egg quality, bone mineral density (BMD), levels of osteocalcin (OC), vitamin D, calcium (Ca), phosphorus (P) and alkaline phosphatase (ALP) activity in quail (Coturnix coturnix japonica) during the late laying period. 3. The birds (n = 180; 28 weeks old) were randomly assigned to 6 treatment groups consisting of 6 replicates of 5 birds each in a 2 x 3 factorial arrangement of treatments (temperatures, soy isoflavone concentration). Birds were kept in wire cages in a temperature-controlled room at either 22 degrees C (thermo-neutral, TN) or 34 degrees C (heat stress, HS) for 8 h/d (09:00 to 17:00 h; until the end of the study) and fed either on a basal (control) diet or on the basal diet supplemented with either 400 or 800 mg of soy isoflavones/kg of diet. 4. Heat exposure reduced feed intake, egg production, egg quality, BMD, OC, vitamin D, Ca, P and ALP when the basal diet was given. Feed intake, egg production and egg weight were not affected, while eggshell thickness and eggshell weight increased in soy isoflavone-supplemented quails reared under TN conditions. However, feed intake, egg production, egg weight, eggshell thickness, eggshell weight and Haugh units were positively influenced by soy isoflavone supplementation in HS groups for quail during the late laying period. Bone mineral density, serum OC, vitamin D, Ca, P levels and ALP activity were significantly improved by soy isoflavone supplementation in both the TN and HS groups in quail during the late laying period. 5. Soy isoflavone supplementation of basal diet significantly improved egg quality and bone mineralisation in quail during the late laying period. 相似文献
2.
The hypothesis that the presence of fish farming zones affects the water quality and plankton communities was investigated in an Aegean Sea fish farm during February, June, September and January 2000–2001. In the spatial coverage, a total of 12 stations were sampled; three of them were reference stations. A variance analysis was applied to the measurements made at the stations near the fish farms and at the control stations. While no significant differences in concentrations of nutrients, chlorophyll a, particulate organic carbon and particulate organic nitrogen were detected between the stations and the control sites within one season, significant differences were detected between the parameter values measured except for total dissolved phosphorus and dissolved organic phosphorus at different seasons. The seasonal differences were also significant with regard to the biodiversity. Together with these temporal differences in general, there was a higher diversity of species at the control site as compared with the other stations in September, which was the key season to detection of significant changes. The most important consideration is that it is not sufficient to take the instantaneous values for the physico‐chemical variables; rather, it is necessary to monitor the biological parameters in order to define the differences in the ecosystem. 相似文献
3.
The efficacy of dietary curcumin on growth performance,lipid peroxidation and hepatic transcription factors in rainbow trout Oncorhynchus Mykiss (Walbaum) reared under different stocking densities 下载免费PDF全文
Fatih Akdemir Cemal Orhan Mehmet Tuzcu Nurhan Sahin Vijaya Juturu Kazim Sahin 《Aquaculture Research》2017,48(8):4012-4021
4.
Orhan Tufan Eroldoan O. Tabozan S. Tabakolu 《Journal of the World Aquaculture Society》2008,39(2):267-274
The effect of restricted feeding on growth, feed efficiency, and body composition was studied in juveniles of gilthead sea bream, Sparus aurata. Juveniles (6.4 g) were stocked into 12 tanks at a density of 16 fish per tank. Four different feeding schedules were tested on triplicate groups of juvenile fish: (1) control fed for 48 d without deprivation, (2) starvation for 1 d and then refed for 2 d (S1), (3) 50% satiation for 2 d and then refed to apparent satiation for 2 d (R2), and (4) 50% satiation for 6 d and then refed to apparent satiation for another 6 d (R6). Results indicated that all fish subjected to cycled restricted feeding regimes were unable to achieve catching up with control group. The specific growth rate of fish in the control was significantly higher than those in S1, R2, and R6, which were not significantly different from each other. Protein efficiency and protein productive value were significantly higher in R2 compared to control, S1, and R6. Fish in R2 had lowest feed conversion ratio (1.12) compared to the control (1.17). Body protein composition in R6 was less than that of the control, S1, and R2, while moisture, lipid, and ash content were not significantly different compared to the control. 相似文献
5.
Tongjun Ren Shunsuke Koshio Orhan Uyan Connie Fay Komilus Saichiro Yokoyama Manabu Ishikawa Md Kadel Abdul 《Journal of the World Aquaculture Society》2008,39(6):797-803
A trial was conducted to determine the effect of ascorbyl‐2‐monophosphate Na/Ca (AMP‐Na/Ca) on blood chemistry and nonspecific immune response of red sea bream juveniles. Test diets with three levels of AsA (free, 107, and 325 mg/kg diet) were fed to juvenile red sea bream (36.0 ± 1.3 g) two times a day for 3 wk. There were no significant differences in hematocrit, glucose, and blood urea nitrogen. Total cholesterol and triglyceride in plasma of fish fed AsA‐free diet was significantly (P < 0.05) higher than that of fish fed two other diets. There were no significant differences in serum albumin, total bilirubin, and total serum protein. Glutamyl oxaloacetic transaminase in serum of fish fed diets containing 107 and 325 mg of AsA were significantly (P < 0.05) lower than that of fish fed AsA‐free diet. Serum lysozyme activity (LA) of fish fed diets containing 107 and 325 mg of AsA were significantly (P < 0.05) higher than that of fish fed AsA‐free diet. There was no significant difference in mucus LA. The results mentioned above demonstrated that AMP‐Na/Ca is a bioavailable AsA source for red sea bream juveniles. Supplement of more than 107 mg AsA/kg in diets improved blood chemistry and nonspecific immune function of red sea bream juveniles. 相似文献
6.
Burcu Sancar Beşen Onur Balcı Cem Güneşoğlu Mehmet Orhan E. İnci Somuncuoğlu İ. İrem Tatlı 《Fibers and Polymers》2017,18(6):1079-1090
In this paper, it was aimed to obtain disposable medical textiles having antibacterial and wound healing properties, as well as biological adaption. For this purpose, the St. John’s Wort oil and flax seed oil were ozonated, and the oils were capsulated with arabic gum. The produced ozonated oils were characterized through FTIR and TGA analyses, as well as the properties of antibacterial, wound healing, and biological adaption were investigated. The produced microcapsules were examined via optical microscope and FTIR. The characterized microcapsules of the ozonated oils were applied to the textiles with padding method. After the applications, the fabrics were researched with SEM and FTIR analyses; in addition the antibacterial and wound healing properties and biological adaption of the textiles were also investigated. The results showed that the St. John’s Wort oil and flax seed oil were successfully ozonated and microcapsulated. The microcapsules of the oils could be applied to the fabric samples with the determined application recipe. The ozonated oils and the fabric samples applied microcapsules of the ozonated oils gained high antibacterial and wound healing property. In addition, the fabric samples were produced as having biological adaptation. 相似文献
7.
Distribution of immunoglobulin-bearing cells in the gut-associated lymphoid tissues of the turkey: effect of antibiotics 总被引:2,自引:0,他引:2
Distribution of immunoglobulin (Ig)-bearing cells in the gut-associated lymphoid tissues of antibiotic treated and untreated control turkeys (Meleagris gallopavo) was compared. Antibiotic treatment was similar to a regimen used in commercial turkey production, which included preincubation dipping of fertile eggs in gentamicin solution, injection of turkeys with gentamicin at hatching, and inclusion of chlortetracycline in the diet. Tissues were examined from turkeys at 3, 7, 14, and 21 days of age with a direct immunofluorescence procedure. Cell distribution in control turkeys was as follows: In the bursa of Fabricius, IgA-carrying cells predominated at 3 days of age, but at later intervals, the 3 classes of Ig-bearing cells were in equal numbers. In the cecal tonsils, IgM- and IgA-bearing cells were in larger numbers at 3 days of age, whereas, the IgG-bearing cells were sparsely distributed. By 7 days of age, IgM cells became more numerous in the cecal tonsils and remained numerous until 21 days of age. At 3 days of age, IgA cells predominated in the small intestines and IgM cells predominated in the large intestine. At 7 and 14 days of age, IgM cells were more numerous in the small and large intestines, but by 21 days of age, IgA cell population equaled that of IgM. The IgG cells were generally sparse in the intestines. Antibiotic treatment often resulted in lower numbers of Ig-positive cells, especially those bearing IgM and IgA. Normal development of the bursa of Fabricius was also retarded in this group. 相似文献
8.
The aim of this study was to determine if the negative effects of high ambient temperature (34 degrees C) on egg production, egg quality, digestibility of nutrients, and mineral content of egg yolk could be alleviated by dietary vitamin E (dl-alpha-tocopheryl acetate) supplementation in laying Japanese quails (Coturnix coturnix japanica). Japanese quails (n=240; 7-week-old) were divided into eight groups, 30 birds per group. The quails were fed either a basal diet or the basal diet supplemented with either 125, 250 or 500 mg of dl-alpha-tocopheryl acetate/kg of diet. Birds were kept at 22 degrees C and 55% relative humidity (RH). At 14 weeks of age, the thermo-neutral (TN) group remained in the same temperature as at the beginning of the experiment, whereas the heat stress (HS) group was kept at an environment-controlled room at 34 degrees C and 44% RH for 3 weeks. Heat exposure decreased performance when basal diet was fed (P=0.001). With 250 and 500 mg/kg of diet, an increase in body weight (P=0.01), feed intake (P=0.01), egg production (P=0.001), and improvement in feed efficiency (P=0.01) was found with vitamin E supplementation in quails reared under heat stress conditions (HS). Similarly, egg weight (P=0.01), egg specific gravity (P=0.01), egg shell thickness (P=0.05) and Haugh unit (P=0.01) were positively influenced by vitamin E supplementation. Heat exposure decreased digestibility of dry matter (DM) (P=0.03), organic matter (OM) (P=0.05), crude protein (CP) (P=0.02), ether extract (EE) (P=0.05) and were elevated by supplemental vitamin E (P相似文献
9.
Naziroglu M Sahin K Simsek H Aydilek N Ertas ON 《DTW. Deutsche tier?rztliche Wochenschrift》2000,107(5):199-202
The aim of this study was to investigate the effects of feed withdrawal and darkening on the antioxidative status of laying hens in high ambient temperatures between 30-40 degrees C. We determined vitamins A and E, lipid peroxidation as thiobarbituric-acid reactive substances (TBARS), glutathione peroxidase (GSH-Px) and reduced glutathione (GSH) in the serum, liver and muscle. Sixteen week old hens (Ross Brown) were divided into 3 groups of 30 hens each. The first group was used as a control. Hens in the second (feed withdrawal) group were subjected to feed removal between 14-18 h during the summer. Hens in the third (darkening) group were subjected to darkening of the hens house with black curtains between 14-18 h. At the end of 16 weeks, blood serum, liver and breast muscle samples were taken from all animals and analysed. Vitamins A and E levels in serum and liver were significantly (P < 0.05, P < 0.01) higher in feed withdrawal and darkened groups than in control group whereas the serum levels of the darkening group were highest. GSH-Px activity and GSH level in liver and muscle were also significantly (P < 0.05, P < 0.01) higher in feed withdrawal and the darkening group than in control. However, TBARS levels in liver and muscle were significantly (P < 0.05, P < 0.01) lower in feed withdrawal and darkening groups compared with control group, whereas the level of the darkening group was the lowest. In conclusion, we observed that feed withdrawal and darkening of hens in high temperatures during summertime resulted in an increase of antioxidant enzymes and vitamins levels and in a decrease of lipid peroxidation. 相似文献
10.
Although of considerable agronomic importance, our understanding of B toxicity mechanism in plants is still not completely understood, and remains an open question. Therefore, we investigated the effect of increasing levels of B (0, 10, 20 and 30 mg kg−1) on the growth, boron (B) concentrations, stomatal resistance, lipid peroxidation (MDA), membrane permeability (MP), lypoxygenase activity (LOX), proline (PRO) and H2O2 accumulation, and the activities of major antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT and ascorbate peroxidase, APX) of grapevine (Vitis vinifera L. cv. Kalecik Karasi) grafted on 5BB rootstock (V. berlandieri × V. riparia) was investigated. Applied toxic levels of B significantly reduced leaf and root growth and increased the B concentration of the leaf, and stem, bark and root of rootstock. In the all B levels leaf tissues of grapevine accumulated more B than that of the other plant parts. In order to restrict excessive uptake of B, stomatal resistance of the leaves increased especially at high B treatments (20 and 30 mg kg−1). The concentrations of H2O2, MDA and membrane permeability were increased as the result of B toxicity while proline and the activity of lypoxygenase were decreased. Compared with control plants, the activities of SOD and CAT were increased by B treatments while the activity of APX was decreased. To our knowledge, this is the first report that B toxicity elevated the antioxidant enzymes to protect the membrane functions from reactive oxygen species (ROS) injury in grapevine and it was hoped that this study would provide a basis for developing strategies for reducing the risks associated with B toxicity. 相似文献