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11.
Yeast probiotics have great promise, yet they received little attention in fish. This study investigated the influence of Aqualase®, a yeast‐based commercial probiotic composed of Saccharomyces cerevisiae and Saccharomyces elipsoedas, on health and performance of rainbow trout (Oncorhynchus mykiss). Probiotics were incorporated in the diets at three different inclusion levels (1%, 1.5% and 2%) and administered to the fish for a period of 8 weeks. After the feeding trial, intestinal total viable aerobic bacterial count was significantly higher in fish group that received 2% in‐feed probiotics. In addition, a significant increase in at least 11% in intestinal lactic acid bacteria population was observed in all probiotic‐fed groups. Total protein level and lysozyme activity in skin mucus were significantly elevated following probiotic feeding. Inhibitory potential of skin mucus against fish pathogens was significantly enhanced by at least 50% in probiotic‐fed groups. Humoral and cellular immune parameters were influenced by probiotic feeding and the effects were dependent on inclusion level. Digestive physiology was affected by in‐feed probiotics through improvement of intestinal enzyme activities. All growth performance parameters were significantly improved following probiotic administration specifically at inclusion rate 1.5% and above. Taken together, the results revealed that Aqualase® is a promising yeast‐based probiotic for rainbow trout with the capability of modulating the intestinal microbiota, immunity and growth.  相似文献   
12.
OBJECTIVE: To evaluate L-selectin (CD62L) and Mac-1 (CD11b) expression at the surface of blood and milk neutrophils during the early inflammatory response to Escherichia coli-induced mastitis in cows. ANIMALS: 6 healthy Holstein heifers in early lactation. PROCEDURE: Blood and milk samples were collected before and after intramammary administration of 10(4) CFU's of E coli in the left mammary gland quarters. Bacterial counts and electrolyte concentrations in milk, rectal temperature, differential blood leukocyte counts, milk somatic cell counts, neutrophil viability, and the expression of CD62L and CD11b on blood and milk neutrophils were determined longitudinally. RESULTS: Bacteria grew during the first 6 hours after inoculation with a pronounced leukocytic influx. Coincident with neutrophil influx was an increase in CD62L+ and CD11b+ milk neutrophils, as well as an improved viability of milk neutrophils. The peak of the inflammatory reaction was reached approximately 12 hours after E coli inoculation. From that time forward, changes in CD62L and CD11b expression were opposed to each other, with a decrease in CD62L expression and an increase in CD11b expression on blood and milk neutrophils; the magnitude of the differences in CD62L and CD11b expression between blood and milk neutrophils decreased. Percentages of CD62L+ and CD11b+ milk neutrophils increased to percentages that were similar to blood neutrophils (ie, approx 92%). CONCLUSIONS AND CLINICAL RELEVANCE: The presence of adhesion molecules on a large percentage of milk neutrophils during the acute inflammatory response, together with the changes in receptor density, suggest a major role for CD62L and CD11b in neutrophil function during coliform mastitis.  相似文献   
13.
Effects of three insecticides, diazinon, fenitrothion and chlorpyrifos on Andrallus spinidens Fabricius (Hemiptera: Pentatomidae), a predator of lepidopterous larvae in rice fields were investigated. The insecticides were applied topically at lethal dose (LD30) on the fifth instar nymphs of A. spinidens and evaluated on life table and some biochemical parameters of the predatory bugs. The results showed that pre-oviposition period, fecundity and longevity of treated bugs were significantly affected compared with the control. Analysis of life table parameters of A. spinidens revealed adverse effects of insecticides on net reproductive rate (R0), intrinsic rate of increase (r), finite rate of increase (λ), doubling time (DT) and mean generation time (T). Among the tested insecticides, fenitrothion was the most toxic insecticide. The lowest value of r was 0.060 day?1 in fenitrothion. Effects of insecticides on the detoxification enzymes showed that all compounds had inhibitory effect on esterases, acetylcholinesterases and glutathione S-transferases. According to this study, the insecticides cause harmful effects on demographic and biochemical parameters of A. spinidens and are not compatible with the predatory bug even at sublethal concentration.  相似文献   
14.
Anatomical and histological studies of the large intestine in birds are essential for necropsy and histopathological examinations. On the other hand, large intestine plays a critical role in the immune system and absorption. The present study's objective was to provide information about the morphological, morphometric and histological characteristics of the large intestine in see-see partridges (Ammoperdix griseogularis) and pheasants (Phasianus colchicus). These two members of the Galliformes order are found in large areas of Iran. In this study, ten male see-see partridges and ten male pheasants were randomly selected. Also, the histological studies were carried out on tissue specimens using haematoxylin for staining. In both species, the cecum was visible as two large tubes at the beginning of the rectum. The cecum and rectum's outer surfaces were flat and had no sacculation in both of the birds. Histologically, intestinal villi in all the large intestine parts and increase their height from the base to the apex is remarkable. The muscularis mucosae was distinct, and lymph nodes and Liberkuhn glands were found in all parts of the large intestine, approximately. It can be concluded that the morphology of the large intestine is very similar to the other avian species, but there are more differences in the histological features. These structural features are in full accordance with the bird's habits and diet.  相似文献   
15.
In this present study, we investigated the effects of cocoa extract containing polyphenols and methylxanthines prepared from cocoa powder on the biochemical parameters of obese-diabetic (Ob-db) rats. Obese-diabetic (Ob-db) rats were developed using a high-fat diet (49% fat, 32% carbohydrate, and 19% protein from total energy, kcal) for 3 months, followed by a low dose (35 mg/kg body weight) streptozotocin (STZ) injection. Cocoa extract (600 mg/kg body weight/day) was given to the rats for 4 weeks. The results indicated that there were no significant differences in fasting plasma glucose and insulin level after 4 weeks of cocoa extract administration. Oral glucose tolerance test revealed that cocoa supplementation in Ob-db rats significantly (p < 0.05) reduced plasma glucose at 60 and 90 min compared to unsupplemented Ob-db rats. Plasma free fatty acid and oxidative stress biomarker (8-isoprostane) were significantly (p < 0.05) reduced after cocoa supplementation. Superoxide dismutase activity was enhanced in Ob-db compared to that in nonsupplemented rats. However, no change was observed in catalase activity. The results showed that cocoa supplementation had an effect on postprandial glucose control but not for long term (4 weeks). Moreover, cocoa supplementation could reduce circulating plasma free fatty acid and 8-isoprostane and may enhance the antioxidant defense system.  相似文献   
16.
A soil isolate of actinomycete, strain S-70, revealing presence of plasmid(s) was placed in the genus Streptomyces according to the wall composition and morphology. The toxicity of S-70 grown on two fermentation media, glucose-asparagine broth (GAB) and malt extract-yeast extract broth (MYE), against infective larvae of Toxocara canis was assessed. The use of mortality test has provided a sensitive and reproducible bioassay. The results suggest high larvicidal activity of the Streptomyces crude products examined being highly potent when using GAB culture medium.  相似文献   
17.
Spirulina has been highlighted as a valuable complementary ingredient in aquafeeds due to its high protein and vitamin content, in addition to other nutritional benefits. To evaluate the effect of dietary spirulina inclusion in fish meal sparing (FMS) on juvenile Caspian brown trout as a slow‐growth fish, a complete randomized experimental design was developed with five treatments: 0% (control), 2% FMS (13.2 g/kg spirulina in diet), 4% FMS (26.4 g/kg spirulina in diet), 6% FMS (39.6 g/kg spirulina in diet) and 8% FMS (52.8 g/kg spirulina in diet). Six hundred juveniles (11.0 ± 1.0 g) were assigned to 15 experimental tanks. Although this fish is sensitive to diet composition, fish fed the 6% FMS and 8% FMS diets had a significantly higher weight gain rate (239.51% and 231.27%) and specific growth rate (1.74% bw per day and 1.71% bw per day) compared with those fed the control diet. Furthermore, 6% FMS and 8% FMS treatments had statistically higher protein efficiency (0.76 and 0.78), lipid efficiency (1.89 and 1.94) and statistically lower feed conversion ratio (2.47 and 2.41) compared with other treatments, respectively (p < 0.05). In terms of whole‐body composition, the higher amount of protein and lower content of lipid were observed in fish fed the 8% FMS diets as compared to control. Although no significant differences in ash and moisture content were observed, the highest protein deposition (157.3 g/kg) and the lowest lipid content (77 g/kg) in whole body were reported in fish fed 8% FMS diet. Based on the fillet fatty acid outcome, fish fed the 8% FMS diet had significantly higher saturated fatty acids (SFAs), C20:3n‐6, C18:3n‐3, polyunsaturated fatty acids (PUFAs) and total n‐3 fatty acids as compared to those fed the control diet (p < 0.05). Accordingly, increasing dietary spirulina content significantly enhanced the amount of these fatty acids in fish fillet. As regards of whole‐body amino acid profile, arginine and lysine in fish fed 6% FMS and 8% FMS diets were higher and lower than in those fed the control diet, respectively (p < 0.05). Fillet and skin colour parameters, such as luminosity, redness and yellowness, significantly increased with spirulina supplementation with the 8% FMS treatment displaying higher values than the control. In summary, according to our results, 8% FMS (52.8 g/kg spirulina in diet) treatment improved juvenile Caspian brown trout growth, carcass composition and pigmentation.  相似文献   
18.
T evaluate the effect of supplementation with Enterococcus faecium strain SF68 (NCIMB10415) on immune function, responses to a multivalent vaccine were investigated in kittens given palatability enhancer with or without E. faecium SF68 daily. E. faecium SF68 was detected in the feces of seven of nine treated cats. Supplementation of kittens with E. faecium SF68 did not affect developmental parameters. The percentage of CD4+ lymphocytes was significantly higher in the treatment group. There were no statistical differences in measurements of any other nonspecific or specific immune parameters between groups.  相似文献   
19.
Somatic embryogenesis is a routine method in obtaining mass-production of plantlets especially in Musa spp. Somatic embryogenesis is a process characterized by a series of morphological changes leading to plant regeneration. Therefore it is important to identify stages in somatic embryogenesis through morphological and histological characteristics. In this study, stages of somatic embryogenesis through morphohistological study could differentiate between embryogenic callus consisting of somatic embryos and non-embryogenic callus. In Musa spp., globular to torpedo shaped somatic embryos resulted in good suspension cultures followed by recovery of somatic embryos during developmental stage. The morphological observations were supported by histological sections of structures at all particular stages. Histological examination also revealed the vascular connection in germinated somatic embryos which later turned into a complete plantlet.  相似文献   
20.
Potassium (K) uptake rates were determined for Marianna 2624 rootstocks with ‘French’ prune scions using the nutrient solution depletion technique. The nutrient solutions were bubbled with factorial combinations of nitrogen (N2), oxygen (O2), and carbon dioxide (CO2) to create treatment root atmospheres with O2 ranging from 0.01 to 0.10 m3/m3 and CO2 ranging from 0 to 0.05 m3/m3. The K+ uptake rate was more susceptible to O2 deprivation than to elevated CO2 in the root atmosphere. Decreasing O2 levels from 0.10 m3/m3 decreased K+ uptake in a hyperbolic fashion to no net uptake at 0.01 m3/m3 O2. Increasing root atmosphere CO2 from 0 to 0.05 m3/m3 had a small depressing effect on net K+ influx from 60 μM K+ solutions at 0.10 and 0.05 m3/m3 O2, but no effect when O2 was 0.025 or 0.01 m3/m3. Elevating CO2 decreased Km for the net K+ influx rate at 0.10 and 0.05 m3/m3 O2. Increased pH buffering from higher HCO3 concentration at the plasma membrane surface was suggested to explain the CO2 effect on Km.  相似文献   
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