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41.
The aim of the study was to examine the effects of increasing zinc supplementation on growth, feed efficiency and thyroid function and histology in broiler chicks. Sixty new born male broiler chicks were randomly allotted into one of four treatment groups and fed for 60 d. Zinc (Zn) was added into drinking water at the levels of 0, 125, 500, and 1000 mg Zn/L. Body weight gain were significantly higher and feed efficiency were significantly lower in chicks supplemented with 125 mg Zn/L compared with chicks supplemented with 500 or 1000 mg Zn/L at the end of the experiment. Serum Zn concentration linearly increased with the increasing level of Zn intake. Serum triiodothyronine and thyroxine levels and the diameters of follicles of thyroid gland were significantly reduced with high levels (500 and 1000 mg Zn/L) of Zn intake at the end of the experiment. It was concluded that chick receiving 1000 mg Zn/L as ZnSO4.7H2O in drinking water showed signs of Zn toxicity.  相似文献   
42.
1. The aim of this study was to determine the effects of juniper oil (JO) dietary supplementation on the laying performance, egg traits and egg malondialdehyde (MDA) concentrations of quail.

2. A total of 400 female Pharaoh quails were equally divided into 4 groups containing 100 quails (5 replicates of 20 quails each). The study included a control treatment with no diet additives, and the treatments were as follows: (group 1) 100 mg JO/kg; (group 2) 200 mg JO/kg; (group 3) 300 mg JO/kg. The experiment was carried out for 60 d.

3. At the end of the experiment, there were no significant differences in body weight, egg weight, egg mass, egg shape index, yolk colour, egg production, feed consumption or feed efficiency.

4. The Haugh unit was increased in groups 2 and 3 compared to the control group. Dietary fortification with JO improved eggshell thickness and breaking strength compared to the control group. Furthermore, the damaged egg ratio was significantly decreased in group 3 compared to the control. The increasing concentration of JO (200 and 300 mg/kg) caused a significant decrease in egg yolk MDA concentration after 15 and 30 d of storage at 20°C.

5. It was concluded that inclusion of JO in layer diets can improve egg quality characteristics in terms of Haugh unit, eggshell thickness and breaking strength. Moreover, supplementation of JO in the diets of quail may enhance the antioxidant status of eggs, and the most effective doses of JO were 200 and 300 mg/kg.  相似文献   

43.
Inoculants are of great importance in sustainable and/or organic agriculture. In the present study, plant growth of barley (Hordeum vulgare) has been studied in sterile soil inoculated with four plant growth-promoting bacteria and mineral fertilizers at three different soil bulk densities and in three harvests of plants. Three bacterial species were isolated from the rhizosphere of barley and wheat. These bacteria fixed N2, dissolved P and significantly increased growth of barley seedlings. Available phosphate in soil was significantly increased by seed inoculation of Bacillus M-13 and Bacillus RC01. Total culturable bacteria, fungi and P-solubilizing bacteria count increased with time. Data suggest that seed inoculation of barley with Bacillus RC01, Bacillus RC02, Bacillus RC03 and Bacillus M-13 increased root weight by 16.7, 12.5, 8.9 and 12.5% as compared to the control (without bacteria inoculation and mineral fertilizers) and shoot weight by 34.7, 34.7, 28.6 and 32.7%, respectively. Bacterial inoculation gave increases of 20.3–25.7% over the control as compared with 18.9 and 35.1% total biomass weight increases by P and NP application. The concentration of N and P in soil was decreased by increasing soil compaction. In contrast to macronutrients, the concentration of Fe, Cu and Mn was lower in plants grown in the loosest soil. Soil compaction induced a limitation in root and shoot growth that was reflected by a decrease in the microbial population and activity. Our results show that bacterial population was stimulated by the decrease in soil bulk density. The results suggest that the N2-fixing and P-solubilizing bacterial strains tested have a potential on plant growth activity of barley.  相似文献   
44.
Fourier transform infrared (FTIR) and Fourier transform Raman (FT-Raman) methods were used for rapid characterization and classification of selected irradiated starch samples. Biochemical changes due to irradiation were detected using the two vibrational spectroscopic techniques, and canonical variate analysis (CVA) was applied to the spectral data for discriminating starch samples based on the extent of irradiation. The O-H (3000-3600 cm(-1)) stretch, C-H (2800-3000 cm(-1)) stretch, the skeletal mode vibration of the glycosidic linkage (900-950 cm(-1)) in both Raman and infrared spectra, and the infrared band of water adsorbed in the amorphous parts of starches (1550-1750 cm(-1)) were employed in classification analysis of irradiated starches. Spectral data related to water adsorbed in the noncrystalline regions of starches provided a better classification of irradiated starches with 5 partial least-squares (PLS) factors in the multivariate model.  相似文献   
45.
The effects of digoxin and monensin on contraction force (CF), initial contraction velocity (ICV), average contraction velocity (ACV), initial relaxation velocity (IRV) and stimulus to response time (ST) in 'fatigued' (tired) and 'non-fatigued' (fresh) guinea-pig papillary muscles were investigated. 'Fatigued' muscles had lost 30% of their original CF with the elapse of time before they were treated. The 5 h of measurement were divided into five periods (T0 was equilibration, T1, T2, T3 and T4 were, respectively, 1, 2, 3 and 4 h after drug administration). It was found that both monensin and digoxin increased the CF, ICV and ACV at T1 and increased the IRV at T2. Digoxin lost its effect with the elapse of time while monensin did not. Digoxin also decreased the ST at T2, T3 and T4. However, monensin did not change the ST. It was also found that 'fatigued' and 'non-fatigued' guinea-pig papillary muscles did not respond to the drug treatment differently. It was concluded that the initial effects of these two drugs on guinea-pig papillary muscles are similar regarding contractility but in time digoxin loses its effect while monensin does not.  相似文献   
46.
Some important physicochemical and bioactive characteristics of disease free 10 wild grown bilberry (Vaccinium myrtillus) accessions were evaluated. External and internal fruit quality was assessed by standard parameters (fruit weight, fruit color, fruit firmness, soluble solids, pH and total acidity) and bioactive contents (total phenolics, total anthocyanins, total antioxidant capacity and, vitamin C) in fruit were also determined. The commercial grown northern higbush blueberry, Vaccinium corymbosum cv. Bluecrop also included in the study to make comparision with bilberry samples. The highbush blueberry cv. Bluecrop had distinctive external fruit characteristics, such as bigger and more attractive fruits. However, the wild grown bilberry accessions showed interesting characters in mesocarp, such as high total phenolic content, total anthocyanin and total antioxidant capacity. Total phenolic and total anthocyanin content was 327?mg gallic acid equivalent and 142?mg of cyanidin-3-glucoside equivalent in 100?g fresh fruit in cv. Bluecrop while it was between 576–624?mg gallic acid equaivalent and 296–324?mg of cyanidin-3-glucoside equivalent in 100?g fresh fruits of bilberry accessions. Moreover, wild accessions approximately had 2 folds higher antioxidant capacity than cv. Bluecrop. Results suggested that bilberry accessions may serve as a source of desirable genes to develop improved varieties that respond to the new needs of the market.  相似文献   
47.
Formalin (37–40% formaldehyde) is one of the most effective, widely used chemical in pisciculture for its antiparasitic, antifungal and prophylactic activities. It is used in paints, cleaning products and textile industry, as well. Genotoxic and histological effects of sublethal formalin exposure on Nile tilapia (Oreochromis niloticus) are investigated in this study. The semi‐static acute test was employed. One‐tenth, one‐fifth and half of the 96‐h LC50 value, 148 mg L?1, were used as sublethal exposure concentrations: 15, 30 and 75 mg L?1 for 24, 48, 96 and 168 h respectively. The micronucleus test was applied to investigate the genotoxic effects on fish erythrocytes at the end of predetermined exposure periods and all tissues of the fish were sampled for histological examination. The micronucleus frequencies increased significantly in all exposure groups when compared with their control groups in a dose and time dependent manner (< 0.05). Results of histological examination showed no histopathological findings in the gonads, heart, skeletal muscle, spleen and intestine tissues after sublethal formalin exposure. Passive hyperaemia of liver tissue in varying proportions, hydropic degeneration, fatty degeneration in high concentrations, branchitis on gill tissues in varying proportions, epithelial lifting, telangiectasia, bleeding in kidney and hyperaemia were found in Nile tilapia exposed to formalin at different concentrations and durations. As a result, it is thought that formalin leads to tissue damage and shows genotoxic effects even at 15 mg L?1 concentration in O. niloticus.  相似文献   
48.
The present study evaluated the effect of overwintered adult density and egg and adult parasitism rates on the new-generation population densities of the Sunn Pest (Eurygaster integriceps Put.) under field conditions. We quantified the abundance of overwintered adult densities and egg and adult parasitism rates in 20 one-ha unsprayed wheat fields in southeastern Turkey to assess their impact on nymphal instars, plus new-generation adult densities. The number of overwintered adults per square meter and the percent of egg parasitism rates were positively and negatively correlated with new-generation densities of the Sunn Pest, respectively. The results of multiple regression analysis produced the equation Y = 15.037 + 8.287 OW (overwintered adult) − 0.235 egg PR (parasitism rate). The findings suggest that the egg parasitoids may suppress nymphal instars plus new-generation adult densities of the Sunn Pest. The findings also suggest that the present formula can be used to determine the spraying areas in which densities reach economic threshold for the integrated Sunn Pest management program in wheat fields in Turkey.  相似文献   
49.
The aim of this study was to examine the coagulation profile in peste des petits ruminant (PPR) in kids. Five kids from a group of 150 animals (72 goats and 78 kids) were brought to the Veterinary Medical Teaching Hospital from a farm in Burdur province (Turkey) with nasal and ocular discharges and diarrhea. Fifteen goats and 41 kids had died due to diarrhea and three kids were presented to the Department of Pathology for diagnosis. Blood samples were taken from 12 ill animals (infected group) for haematological and biochemical analysis. In addition, five healthy kids were examined from another healthy flock (control group). Leukocyte and lymphocyte numbers of infected group showed significant declinations in comparison to control group (≤0.001). Haemorrhages in all organs of digestive system and small haemorrhagic areas in liver were caused to decrease in erythrocyte and haematocrit values (p ≤ 0.001) in infected group. Concentrations of blood urea nitrogen (BUN) (p ≤ 0.01) and creatinine (p ≤ 0.001) in infected group were significantly higher than control group. Compared to control group, significant increases were determined in serum concentrations of alkaline phosphatase (ALP) (p ≤ 0.01), aspartate aminotransferase (AST) (p ≤ 0.001) and alanine aminotransferase (ALT) (p ≤ 0.001) in the infected group. No significant differences were observed between the infected and control groups for serum gamma glutamyl-transferase (GGT) concentration value. In our study, thrombocytopenia (p ≤ 0.001) together with prolonged activated partial thromboplastin time (APTT; p ≤ 0.01) and prothrombin time (PT; p ≤ 0.001) may show that disseminated intravascular coagulopathy which can occur in kids with PPR.  相似文献   
50.
July 2004, a cow with clinical signs of ovine herpesvirus type-2 infection which is known as sheep associated malignant catarrhal fever (SA-MCF) was reported in Samsun Province in Turkey. Blood samples were collected from the suspected cow, 10 sheep housed with it, and from 150 healthy sheep and 29 healthy cattle randomly selected from different places in Samsun Province. Nested polymerase chain reaction (n-PCR) was used to detect ovine herpesvirus type-2 (OvHV-2) DNA in the suspected cow and competitive- ELISA (c-ELISA) kits were used to detect antibodies against OvHV-2. The suspected cow was found to be n-PCR positive and c-ELISA negative. The serological results were as follows: All 10 (100%) of sheep housed with the suspected cow and 18 of 29 (62%) of the randomly selected cattle were found seropositive. All 150 randomly selected healthy sheep were seronegative. The overall percentage of seropositivity was 14.7% (28/190). OvHV-2 DNA was detected in the peripheral blood leucocyte (PBL) samples of the cow and of the 10 sheep housed with the suspected cow.  相似文献   
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