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991.
  1. The aim of this study was to investigate the effect of dietary supplementation of green tea (Camellia sinensis) catechins in quail (Coturnix coturnix japonica).

  2. Quail were fed with a basal diet, and the treatment groups were fed on the basal diet with 1.25 or 2.50 g/kg catechin supplementation for 30 d.

  3. Fattening performance and meat quality of the quail were estimated. Serum total antioxidant status (TAS), plasma and liver malondialdehyde (MDA) and some serum biochemical parameters were measured.

  4. The results showed that catechin supplementation did not affect live weight, feed intake, feed conversion ratio, carcass weight, carcass dressing or the nutrient composition of breast and thigh meats. The water holding capacity (WHC) of breast meat was increased in the 2.50 g/kg catechin treatment. Catechin supplementation increased the serum TAS, but decreased plasma MDA and liver MDA concentration as well as serum glucose and total cholesterol levels. Serum triglyceride and total protein levels were not affected by catechin supplementation.

  5. In conclusion, catechins have effective antioxidant hypoglycaemic and hypocholesterolaemic properties, as well as having the potential to increase meat quality in fattening quail. On the other hand, catechin supplementation did not have any negative effect on the fattening performance, meat nutrient composition and fattening costs in fattening quail.

  相似文献   
992.
993.
The Sorraia, a critically endangered indigenous Iberian horse breed, is characterized by low genetic variability, high rate of inbreeding, bad sperm quality and subfertility. Here, we studied 11 phenotypically normal but subfertile Sorraia stallions by karyotyping, sex chromosome sperm‐FISH and molecular analysis of FKBP6 – a susceptibility locus for impaired acrosome reaction (IAR). The stallions had normal sperm concentration (>300 million cells/ml), but the numbers of progressively motile sperm (21%) and morphologically normal sperm (28%) were invariably low. All stallions had a normal 64,XY karyotype. The majority of sperm (89%) had normal haploid sex chromosome content, although 11% of sperm carried various sex chromosome aneuploidies. No correlation was found between the percentage of sperm sex chromosome abnormalities and inbreeding, sperm morphology or stallion age. Direct sequencing of FKBP6 exon 4 for SNPs g.11040315G>A and g.11040379C>A revealed that none of the stallions had the susceptibility genotype (A/A‐A/A) for IAR. Instead, all animals had a G/G‐A/A genotype – a testimony of low genetic variability. The findings ruled out chromosomal abnormalities and genetic predisposition for IAR as contributing factors for subfertility. However, low fertility of the Sorraia stallions could be partly attributed to relatively higher rate of sex chromosome aneuploidies in the sperm.  相似文献   
994.
Abstract— Age determinations of whitefish ( Coregonus lavaretus (L.)) were compared in two different tests. In the first test, the readers determined the age of each individual from one calcified structure (scale, otolith, or opercular bone) at a time. The samples from three populations, 50 specimens in each, were mixed so that the readers did not know which population each calcified structure was from. A sample of known-age whitefish was used in the second age determination test, where information such as time of catch, length, weight, and sex was available to the readers. In each of the 50 envelopes the reader got scale impressions and two otoliths, one of which had been burned and ground. In the first test, the precision of the readers was low both between readers and between different structures. In the samples of slow-growing populations, the determinations made from the otoliths showed older ages than the determinations from the scales. In the second age determination test the results were better; 73-90% (average 82%) of the determinations were correct. The use of two calcified structures and the knowledge of the material were considered to improve the accuracy. Age determination bias may occur that affects the age distribution: even though 80% of the fish were aged correctly, an exceptionally strong or weak year class could remain unidentified. The estimation of growth rate seemed less sensitive to incorrect age determination than age distribution.  相似文献   
995.
The parasite population dynamics of a Danish isolate of Gyrodactylus derjavini Mikailov 1975 on immunosuppressed fry of rainbow trout, Oncorhynchus mykiss (Walbaum), were investigated and compared with immunocompetent fry. Immunosuppression was induced 14 days prior to infection by intraperitoneal injections of dexamethasone (fluoro-methyl-prednisolone). Treated and untreated fish were infected by cohabitation with Gyrodactylus-infected donorfish, carrying 4-week-old infections. Initial infections did not differ between the two groups. However, parasite populations increased significantly faster and reached significantly higher levels in the dexamethasone-treated group from day 13 post-exposure and during the following 3 weeks when compared with the untreated group. Microhabitat distribution of parasites on the two host groups differed from day 20 post-exposure, which could indicate a different host response to infection. Changes in the density of superficial mucous cells in the caudal fins were investigated during the course of infection. No differences in mucous cell density between untreated and dexamethasone-treated groups were found.  相似文献   
996.
In Europe, the perforator method (EN 120) is the mostly used laboratory method of the wood-based panel industry. Usually, the measured perforator value depends on the moisture content of the boards. According to DIBt-100, the measured perforator values are corrected to a common moisture content (MC) of 6.5% using an established equation proposed by Jann and Deppe (1990). The correction factor of Jann and Deppe (1990) is based on the assumption that particle- and fibreboards change their perforator values to the same extent regardless whether increasing or decreasing the moisture content in the range of 3 ≤ u ≤ 9%. Application of this correction factor to particle- and fibreboards of higher moisture content than 6.5% can lead to biased corrected results in favour of low emission. The corrected values can also lead to paradoxical relation between the perforator values and emission in the low-emission region.  相似文献   
997.
Wheat bran is an important source of dietary fiber but also contains considerable amounts of phytic acid, which is known to impair mineral absorption. The present study was conducted to investigate the phytic acid reduction in coarse and fine wheat bran by fermentation with the different levels of bakers' yeast (3, 6 and 9%) for 8 h at 30 °C, incubation with the different levels of barley malt flour (2.5, 5.0, 7.5 and 10.0%) for 8 h at pH 5.2 and 55 °C, and autoclaving at the different pH levels (pH 5.0, 4.5, 4.0 and 3.5) adjusted with acetic acid for 2 h. The phytic acid content of the wheat bran was effectively reduced by all treatments, and the phytic acid lost was in the range of 88.4–96.9%. Without addition of yeast or malt flour, or autoclaving without pH adjustment, the phytic acid content of the bran samples was reduced at most to 44.9% of the initial amounts under the investigated conditions. Increasing the concentration of yeast or malt flour or decreasing the pH towards 3.5 did not enhance the phytic acid reduction. The most reduction occurred after 2 h of yeast fermentation and malt flour incubation, and after 30 min of autoclaving, which made up 92–98% of the total phytic acid loss. Extending the treatment periods contributed nominally to further increase in the phytic acid reduction, and the rate of the phytic acid loss decreased progressively.  相似文献   
998.
污泥膨胀的原因及其控制方法   总被引:3,自引:0,他引:3  
污泥膨胀不仅影响出水水质,增大污泥的处理费用,而且极易引起大量污泥流失,严重时可导致整个处理工艺失败。污泥膨胀分为丝状菌性污泥膨胀和非丝状菌性污泥膨胀,主要影响因素有污水水质、溶解氧、污泥负荷、冲击负荷以及运行方式和处理工艺等。通过临时控制措施、工艺设计控制措施、工艺运行控制措施可有效解决污泥膨胀问题。尽管当前有一些理论解释污泥膨胀问题,如表面积/容积比(A/V)假说,动力学理论,饥饿假说理论、NO假设,但缺乏充分的实验证明模型适用与否。需进一步完善污泥膨胀理论,为控制污泥膨胀提供严谨的理论依据。  相似文献   
999.
Leaves lying on the forest floor are a major source of dissolved organic substances in soil and surface waters, and these substances have important effects in those environments. We used zero‐tension lysimeters to study the chemical characteristics of water percolating through litter from various species of forest trees. The leaching rates were greatest in the autumn and declined rapidly thereafter, especially for deciduous litter. During an annual cycle, 2.5–17% of the initial contents of the carbon in the litter was recovered as dissolved organic carbon in percolates. Humus‐like substances, hydrophilic acids and hydrophilic neutral compounds constituted the major fractions of dissolved C. Leachates from deciduous leaf litter were only partly biodegradable, and those from spruce needles were scarcely biodegradable. Low molecular weight organic acids constituted 0–12% of the dissolved organic carbon in the percolates of the first autumn sampling and decreased over time. Acetic and formic acids were present at the largest concentrations, up to 30 μmol l?1 per g litter, and gluconic, pyruvic, fumaric, oxalic and citric acids were also frequent in significant concentrations. Among the aromatic acids, p‐hydroxybenzoic acid was identified in four out of five autumn samples. The organic components in litter leachates are important for the microbial activity in soil and surface waters. The organic acids enhance weathering and translocation of metals by their ability to form complexes. Litter is also a source of inorganic ions in soil solutions. The dominant cations in the percolates were K+, Ca2+ and Mg2+, and spruce litter also yielded large quantities of Al and Fe.  相似文献   
1000.
A powdery mildew resistant double disomic wheat-rye substitution line carrying rye chromosomes 1R and 2R was crossed with normal bread wheats. The F2 generation was analysed cytologically by C-banding. Wheat-rye chromosome translocations involving both rye chromosomes 1R and 2R were frequent in F2. Lines with translocations of 1R and 2R were harvested separately. After four generations of selfing and selection for mildew resistance and fertility, fully fertile resistant lines were selected and analysed cytologically. Lines with 1BL/1RS and 2BS/2RL translocations were identified. The resistance on chromosome 1RS could not be shown to be different from control varieties carrying the same rye segment, while the resistance on 2RL is much broader than the earlier known 2RL derived resistance in the line Transec. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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