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61.
Bromelain is a proteolytic enzyme extracted from Ananas comosus and has great potential to affect several physiological functions. The current study examined the effect of bromelain added to commercial feed at concentrations of 0 g (control), 10 g (B1) and 20 g (B2) per kg diet on growth, feed utilization, intestinal morphology, digestive enzyme and immune response of juvenile Sterlet (Acipenser ruthenus) for 56 days. At the end of this experiment, the highest final body weight was detected in fish fed diet of B2 compared to control. The protein content of whole fish was higher in fish fed diet of B1 and B2, but the content of calcium, iron, copper and zinc was noted lower in fillets of fish fed diet of B1 and B2. Supplementation with bromelain significantly increased the height of mucosal folds, enterocytes and the supranuclear zone of the epithelial cells compared to control diet. The enzymatic activity of lipase and pepsin was significantly (p < 0.05) higher in fish fed diet of B1 and B2. The highest activity of lysozyme, total protein level and total immunoglobulin and the proliferative activity of T and B cells were detected in fish fed diet of B2 compared to control, where no significant (p > 0.05) difference was found in ceruloplasmin, metabolic activity of spleen macrophages and potential killing activity of spleen phagocytes between different treatments.  相似文献   
62.
The aim of this work was to determine the impact of surgically implanted telemetry transmitters (TTs) on the growth, survival, hematological and biochemical indexes, and wound healing in juvenile pikeperch (Sander lucioperca) (body weight 60–90 g). Two incision suturing methods were used—silk sutures (experiment I—group ST) or tissue adhesive (experiment II—group GT). After tagging, the fish were held in a recirculating system for 35 days. No statistically significant differences were noted in the growth or condition indexes analyzed among the fish tagged with TT compared with those from the control groups (untagged). Substantial individual variability was noted, however, in the parameters examined in both the control and tagged groups. Among the hematological indexes, statistically significant differences were only noted in experiment I. Lower values of mean corpuscular volume and mean corpuscular hemoglobin were noted in group ST. Among the biochemical parameters, creatinine was statistically significantly threefold lower, magnesium and alkaline phosphatase (ALP) levels were lower, and ammonia levels were higher in group ST than in the control group. In experiment II, significant differences were only noted for ALP. Tissue adhesive was the superior and more effective method for closing the incision after TT implantation in juvenile pikeperch. This type of suturing facilitated faster healing, and it had less of an impact on juvenile pikeperch welfare.  相似文献   
63.
Proper management of soil organic matter is an important issue in the context of sustainable agriculture. The intensification of production and the loss of organic carbon associated with agriculture reduce the efficiency of production and the quality of the environment, especially in relation to areas exposed to erosion. The aim of this study was to determine the impact of specific tillage systems and plant cover on the organic carbon losses, as well as on runoff and soil losses, over a 6-year study period following the introduction of no-till. The first factor in the experiment was the tillage system: conventional tillage (CT) and no-till (NT). The second factor was plant cover: horse bean, spring wheat and winter oilseed rape. The results showed that runoff was 4.3 ± 0.6% higher under NT than under CT, while soil loss was 66.8 ± 2.7% lower under NT than under CT. Compared to CT, NT limited the total organic carbon losses by an average of 46.0 ± 2.9% and organic carbon bound with sediment losses by 53.2 ± 0.7%, whereas for dissolved organic carbon, there were no significant differences for the tillage systems. The anti-erosion effectiveness of NT was lower in the first year, but it increased in subsequent years after the introduction of this tillage system. Plant cover also had a significant impact on organic carbon losses and soil protection. The crops were ranked according to runoff, soil losses and organic carbon losses in the following order from lower to higher losses: winter oilseed rape > spring wheat > horse bean.  相似文献   
64.
65.
Studies of a spectrum of metabolites found in cereals are becoming one of the primary tools for evaluating their susceptibility to the effects of various environmental agents, such as: pathogens, temperature and precipitation. In order to reduce the effect of the environmental conditions, cultivars were grown under identical cultivation conditions.  相似文献   
66.
Nineteen cycling ewes underwent transrectal ultrasonography of ovaries followed by ovariectomies during the growth phase of the first follicular wave of the interovulatory interval or the proestrus/estrus phase of the cycle. Quantitative ultrasonographic characteristics of the antrum and follicular wall in a total of forty-three ovine antral follicles were examined for correlations with the protein expression of three steroidogenic enzymes (cytochrome P450 17α-hydroxylase, CYP17; cytochrome P450 aromatase, CYP19; and 3β-hydroxysteroid dehydrogenase, 3β-HSD) determined by densitometric analysis of immunohistochemical slides, follicular dimensions, granulosa layer thickness and the percentage of apoptotic granulosa cells. Significant correlations were found between echotextural attributes of ovine antral follicles and the percentage of apoptotic granulosa cells, CYP17 expression (theca), CYP19 expression (granulosa) and 3β-HSD expression (theca cells). Computer-aided analyses of ultrasonographic images can be beneficial to the development of assisted reproductive technologies and diagnosis of hormonal imbalances without the need for ovarian biopsies or hormone assays.  相似文献   
67.
Lake Zywiec is a man-made lake constructed in 1965 on the Sola River, Beskidy Mountains (South Poland). The lake is the largest one in a flood control reservoir system known as the Sola Cascade. In May and September 1970, separated by a big flood event in July, the lake was sampled for rock magnetic, chemical and granulometric studies. In 85% of the September samples, susceptibility decreases by 10 to 40% compared to the value measured in May. Seasonal changes are also observed in the total Fe content and some heavy metals. A general decrease in Zn, Pb, Cd, Cu and Cr content during the summer season was observed in the whole lake. The content of other metals such as Mn and Ni increased in samples taken in September. The changes observed in the lake sediments could be only an accidental result of the flood or may indeed result from seasonal changes fostered by the flood effect.  相似文献   
68.
The influence of dusts from aluminium (AP), zinc and lead (ZP1, ZP2), sintering (SP) and power (PP) plants on organic matter accumulation on the forest floor of a mixed oak-pine forest was studied in Niepo?omice Forest near Kraków, Poland. An artificial application of the dusts on experimental plots was used corresponding to 100, 500, 1000, 2000, and 5000 t km?2. Increased organic matter accumulation was observed 5 yr following the addition of AP, ZP1 and ZP2 dusts, while SP and PP dusts at levels > 100 t km?2 caused a slight decrease in litter accumulation. Statistical analysis indicated that Cd, Mn, Pb and Zn present in industrial dusts were responsible for the increase in litter accumulation, while some nutrients (e.g. K, Mg, Na) contained in the dusts might decrease organic matter storage to some extent.  相似文献   
69.
The rapid rise in obesity-related diseases has increased interest in oral and dietary agents that disrupt fat metabolism, resulting in the excretion of dietary lipids in the feces. In this study, a rapid and convenient liquid chromatography method to comprehensively analyze fecal lipids in a single injection was developed. An evaporative light-scattering detector (ELSD) for routine analysis or atmosphere pressure chemical ionization tandem mass spectrometry [(+)APCI-MS/MS] for structural confirmation and peak purity was used. The method was applied to characterize lipid components of feces from hamsters fed high-fat diets with either 5% microcrystalline cellulose or 5% hydroxypropyl methylcellulose (HPMC) fibers, to test the effect of HPMC on lipid metabolism. HPMC is a nonfermentable, soluble cellulose fiber. The fecal lipid components identified using this method includes two secondary bile acids, deoxycholic acid, lithocholic acid, and neutral sterols including cholesterol, coprostanol, stigmastanol, and sitosterol. The profile of fecal lipid components was compared between two groups. It was found that the bile acid excretion was increased 2-fold in HPMC-fed hamsters. More interestingly, diacylglycerides and triacylglycerides were detected in feces from hamsters on HPMC-included high-fat diets. We believe that this is the first report of excretion of acylglycerides following neutral soluble fiber feeding.  相似文献   
70.
We investigated in Syrian Golden hamsters the biological impact and its underlying mechanism of single whole grain breads supplemented with 2-3% hydroxypropyl methylcellulose (HPMC), a semisynthetic viscous soluble dietary fiber (SDF) as a substitute for gluten. Hamsters were fed high-fat diets supplemented with 48-65% (w/w) differently ground, freeze-dried single grain breads including whole grain wheat, barley, barley supplemented with HPMC, debranned oat, and oat supplemented with HPMC which were compared to a diet containing microcrystalline cellulose (control). All single grain breads significantly lowered plasma LDL-cholesterol concentrations compared to the control. Enrichment with HPMC further lowered plasma and hepatic cholesterol concentrations. Despite the reduced molecular weight of naturally occurring soluble (1--->3),(1--->4)-β-d-glucan (β-glucan) caused by the bread-making process, whole grain barley breads downregulated hepatic expression of CYP7A1 and HMG-CoAR genes that are responsible for bile acid and cholesterol synthesis, suggesting a possible role of bioactive compounds such as short-chain fatty acids and phenolic compounds from barley bread. Barley bread enriched with HPMC downregulated expression of ABCG5 gene. Taken together, it appears that distinctive modulation of synthesis and excretion of hepatic cholesterol and bile acid contributes to the cholesterol-lowering properties of whole grain barley breads and breads enriched with HPMC. These data suggests that alternative whole grain breads supplemented with HPMC may provide consumers with a staple food that can assist in cholesterol management.  相似文献   
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