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101.
We investigated the effect of soybean and chicken egg lecithin on the growth performance, fatty acid profile and body composition of rainbow trout fry. Seven isonitrogenous and isolipidic diets were prepared by replacing 0, 2, 4 and 6 % soybean and egg lecithin instead of soybean oil in diets. Trout fry with initial average weight 120 ± 4.08 mg were randomly distributed in twenty-one 90-L tanks. Triplicate groups (165 fish per tank) of fry were fed to visual satiation at six meals per day for 40 days. Incorporation of 2 and 4 % egg lecithin led to increase in final weight, specific growth rate and weight gain compared with control group. Also, 4 % soybean lecithin had moderate effects on growth performance of fry. The fatty acid compositions of fry were influenced by dietary fatty acid. Fish fed egg lecithin showed higher amount of monounsaturated fatty acid than soybean lecithin and control groups. Fry fed soybean lecithin had significantly higher levels of polyunsaturated and n-6 fatty acid than egg lecithin and control groups. Soybean and egg lecithin induced higher amount of highly unsaturated fatty acid in lecithin groups compared with control group. The lipid and ash content of whole-body tissues were positively affected by percentages of soybean and egg lecithin in the diets. So 6 % soybean and egg lecithin induced higher amounts of lipid and ash body content. The results of our study indicated that dietary egg lecithin had growth-promoting effect, and rainbow trout fry had moderate lecithin requirement (at least 2 % as fed).  相似文献   
102.
103.
In this study, the effects of spermiation time are investigated on milt quality of Russian sturgeon over the course of the spawning season. The milt samples were collected from three broodstock batches at three time points including: the beginning, middle and at the end of the spawning season. According to the results, the milt quality parameters including pH, sperm density, spermatocrit, duration of sperm motility and percentage of sperm motility were significantly low in the beginning and end of season than middle of season. The values of milt quality parameters in the middle of season were as follows: (motility percentage: 69.6 ± 3.5, motility duration: 460.3 ± 37.2 s, sperm density: 8.7 ± 0.4 × 109, milt volume: 86.3 ± 8.1 and milt pH: 8.3 ± 0.15). Significant positive correlations were also found between milt pH and sperm motility as well as between sperm density and spermatocrit. In conclusion, our study showed that the middle of season is the best time for collection of milt with appropriate quality in Russian sturgeon. Selection of milt with good quality is necessary aim to cryopreservation of spermatozoa in endangered fish species including Russian sturgeon.  相似文献   
104.

Background:

Serologic screening of gastric cancer (GC) by serum pepsinogens (sPG) levels and Helicobacter pylori (Hp) sero-status, though highly informative, has provided heterogeneous results. Here, we have evaluated the modifying effects of demographic factors on the risk impact of Hp sero-status/sPG levels in gastric cancer, with particular emphasis on age.

Methods:

A cross-sectional study was carried out on 1341 individuals (GC = 578, healthy = 763), who were stratified into two age groups: 35-59 years (middle-aged, n = 830) and ≥ 60 years (60 years-plus, n = 511). Demographic factors and serological states (Hp sero-staus and sPG levels) were recorded by subject interview and serum ELISAs, respectively. Covariate-specific odds ratios were calculated by multivariable logistic regression.

Results:

Hp infection was consistently associated with increased sPGI and sPGII levels in the 60 year-plus, but not the middle-aged group. The joint examination of the variable states of the three serum biomarkers (Hp serology, sPGI, and sPGI/II ratio), in the 60 year-plus age group, demonstrated a stepwise escalation of risk from the single (sPGIlow; OR = 2.6), to double (sPGIlow/sPGI/IIlow; OR = 3.55, and Hppositive/sPGIlow; OR = 5.0) and ultimately triple (Hppositive/PGIlow/PGI/IIlow; OR = 10.48) positive states, in reference to the triple negatives. However, this pattern was not exhibited in the middle-aged subjects.

Conclusion:

Age was clearly identified as a modifying factor on the risk projection of the combined states of Hp serology and sPG levels in gastric cancer screening, reflected by the augmented (~10.5 fold) risk of GC in the triple positive (Hppositive/sPGIlow/sPGI/IIlow) 60 year-plus subjects, which was not evident in the middle-aged group. Key Words: Biomarkers, Demography, Age Distribution  相似文献   
105.
Results document, for the first time, the role of soil moisture on a unique, tripartite, host-specific rhizosphere interaction (i.e., Cucumis melo-Monosporascus cannonballus-Olpidium bornovanus). Specifically, colonization of cantaloupe roots by zoospores of O. bornovanus and germination of ascospores of M. cannonballus were highest at a soil matric potential of ?0.001 MPa but significantly inhibited at a matric potential of only ?0.01 MPa. Matric water potentials of ?0.01 MPa or drier are characteristically inhibitory to the motility of zoosporic microbes but not hyphal growth of filamentous fungi like M. cannonballus. These results support our previous conclusion that germination of ascospores of M. cannonballus, a destructive root pathogen of cantaloupe is mediated by O. bornovanus, an obligate, zoosporic fungus.  相似文献   
106.
Salinity is a major abiotic stress that limits rice production across rice areas as high‐yielding modern rice varieties are generally sensitive to salt stress. The study was conducted to deduce heritability and combining ability estimates of rice for various morphological and physiological traits using a 7 × 7 full‐diallel‐cross analysis at seedling and reproductive stages. The salinity stress treatment was 12 dS m?1 at the seedling stage and 8 dS m?1 at the reproductive stage. Diallel analysis revealed high for salinity tolerance scores and shoot height, moderate for shoot dry weight and root dry weight and low for Na+ and K+ concentrations and K+/Na+ ratio. The low‐to‐moderate narrow‐sense heritability for number of panicles, number of fertile spikelets, grain weight, spikelet fertility and K+/Na+ ratio suggests a large breeding population and delayed selection for tolerance until later generations. Significant maternal effects indicate that selection of the female parent is very important for desired trait development. The results of this study confirmed that salinity tolerance at the seedling and reproductive stages is regulated by a different set of genes that could be pyramided using different donors to enhance the level of tolerance.  相似文献   
107.
In this work, silver iodide (Ag(I)) ions were separated via the carrier element-free coprecipitation (CEFC) method using an organic coprecipitating agent, 1,6-diamino-4-(4-chlornphenyl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile [DCODD] prior to its determination by ?ame atomic absorption spectrometry (FAAS). Analytical parameters including pH of aqueous solution, amount of DCODD, standing time, centrifugation rate and time, and sample volume were studied and optimized. Under the best experimental conditions, it was found that extraction can be performed from the sample volume of 500.0 for silver ion (preconcentration factor of 100.0). Linearity was maintained between 0.006 and 1.50 µg.mL?1 for silver. Detection limit for silver based on 3Sb was 1.60 ng.mL?1. The relative standard deviation of eight replicate measurements of 0.20 µg.mL?1of silver was 2.10%. Finally, the developed method was successfully applied to extraction and determination of the silver ions in the Lepidium draba L plant, water and standard samples and satisfactory results were obtained.  相似文献   
108.
The aim of this study was to investigate the role of acute-phase protein concentration and metabolic status in the establishment and resistance of clinical endometritis (CE) and subclinical endometritis (SE) in dairy cows. We also characterised the treatment-related changes in the concentration of acute-phase proteins and metabolic variables in dairy cows affected by CE and SE. Cows of the SE and CE groups presented a significantly higher β-hydroxybutyrate (BHB), haptoglobin and total sialic acid (TSA) concentrations compared with a healthy group of animals. A significantly lower serum calcium concentration, and a significantly higher serum aspartate aminotransferase activity in the CE group, were observed when compared with SE and healthy groups. The comparison of parameters before treatment indicated that cows suffering from CE or SE with lower concentrations of hepatic and inflammatory markers showed a better response to further treatment, and endometritis was not detected in the second examination. Moreover, decreased concentrations of BHB, acute-phase proteins and hepatic markers were observed after successful treatment for endometritis in CE and SE cows. The results obtained in this study suggest that improved liver function and a decrease in the acute-phase protein concentration might favour the resolution of endometritis after treatment.  相似文献   
109.
In this study, viral pathogens associated with nine outbreaks of naturally occurring dairy calf pneumonia in Mashhad area of Khorasan Razavi province from September 2008 to May 2009 were assessed. Five diseased calves from each farm were chosen for examination. Acute and convalescent serum samples were taken from calves with signs of respiratory disease. Sera were analyzed for antibodies to bovine viral diarrhea virus (BVDV), bovine herpesvirus type 1 (BHV-1), bovine respiratory syncytial virus (BRSV), parainfluenza virus type 3 (PI-3V), and bovine adenovirus-3 (BAV-3) by indirect ELISA kits. Among 42 serum samples collected at sample 1, seroprevalence values for viruses BHV-1, BVDV, BRSV, PI-3V, and BAV-3 were 61.9% (26), 57.1% (24), 64.2% (27), 90% (38), and 61.9% (26), respectively. Seroconversion to BVDV, BRSV, PI-3V, and BAV-3 occurred in 11.9% (5), 16.6% (7), 26.1% (11), and 21.4% (9) of animals, and 52.3% (22) had generated antibodies against one or more viral infections at sample 2. In addition, no significant relationship between seroprevalence of BHV-1, BVDV, BRSV, PI-3V, and BAV-3 and dairy herd size was observed (P > 0.05). According to serological findings, BHV-1, BVDV, BRSV, PI-3V, and BAV-3 are common pathogens of the dairy calf pneumonia in dairy herds in Mashhad area of Khorasan Razavi province, Iran.  相似文献   
110.
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