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排序方式: 共有26条查询结果,搜索用时 15 毫秒
1.
The current study investigated the effects of oyster mushroom Pleurotus ostreatus, extract on immunological and hematological parameters of rainbow trout, Oncorhynchus mykiss. The fish were fed diets containing 0 (control), 1, and 2% supplementation of the oyster mushroom extract for 6 wk. Blood samples were collected weekly for the first 6 weeks. After 6 wk of feeding, the fish were challenged with Lactococcus garvieae and mortality was recorded. The results of this study showed that feeding rainbow trout an oyster mushroom extract–supplemented diet stimulated phagocytic activity of phagocytic cells, lysozyme activity, and myeloperoxidase activity in serum, but it did not significantly affect the total serum immunoglobulin level. At the same time, a significant increase was found in the number of neutrophils, monocytes, and total white blood cells. Fish fed the diet supplemented with oyster mushroom extract showed reduced mortalities following L. garvieae infection compared with controls. These results show that supplementation of fish diets with oyster mushroom extract at 1 and 2% concentrations significantly imrpoves hematological parameters and modulates the immune response against L. garvieae in rainbow trout.  相似文献   
2.
The effects of dimethoate on hematological, biochemical parameters, and behavior were investigated in Oncorhynchus mykiss exposed to sublethal concentrations of 0.0735, 0.3675, and 0.7350 mg/l for 5, 15, and 30 days. Significant decrease was determined in erythrocyte and leukocyte counts, hemoglobin, hematocrit, MCV, and MCH, which was pronounced after prolonged exposure indicating the appearance of microcytic hypochromic anemia. There were no prominent changes in thrombocyte and MCHC. The glucose concentration showed an ascending pattern that proved to be positively correlated with duration. The protein concentration declined in higher dimethoate concentrations following 15 and 30 days. Negative and significant correlation was detected between glucose and protein concentrations. The fish showed remarkable behavioral abnormality such as loss of balance, erratic swimming, and convulsion. Present findings revealed that dimethoate exerts its toxic action even in sublethal concentrations and hematological parameters and abnormal behavior may be sensitive indicators to evaluate pesticide intoxication.  相似文献   
3.
Black carrots contain anthocyanins possessing enhanced physiological activities. Explants of young black carrot shoots were cultured in Murashige and Skoog (MS) medium for callus initiation and were transferred to new MS medium supplemented with four different combinations of 2,4-dichlorophenoxyacetic acid and kinetin. Subsequently, the lyophilized calli and black carrot harvested from fields were subjected to ultrasound extraction with ethanol at a ratio of 1:15 (w:v). Obtained extracts were applied to various human cancer cell lines including MCF-7 SK-BR-3 and MDA-MB-231 (human breast adenocarcinomas), HT-29 (human colon adenocarcinoma), PC-3 (human prostate adenocarcinoma), Neuro 2A (Musmusculus neuroblastoma) cancer cell lines and VERO (African green monkey kidney) normal cell line by MTT assay. The highest cytotoxic activity was achieved against Neuro-2A cell lines exhibiting viability of 38–46 % at 6.25 μg/ml concentration for all calli and natural extracts. However, a significantly high IC50 value of 170.13 μg/ml was attained in normal cell line VERO indicating that its natural counterpart is an ideal candidate for treatment of brain cancer without causing negative effects to normal healthy cells.  相似文献   
4.
In this study, the influence of a branched‐chain amino acid blend (BCAA composed of 3 l ‐leucine:1 l ‐valine:2 l ‐isoleucine) injected into the amniotic fluid was evaluated for embryonic growth, yolk‐sac (YS) utilization and development of gastrointestinal tract (GIT) and skeletal muscles of turkey embryos from day 24 of incubation (24E) to hatching, together with hatchability, poult quality and liver L* (lightness), a* (redness) and b* (yellowness) values at hatch. At day 22 of incubation, embryonated eggs (n = 240) were assigned to three treatments, that is, eggs were not injected (control, NC) or injected with 1.5 ml sterile solution with 0.9% salt (SA) or 0.2% BCAA blend (BCAAb). These solutions were injected manually into the amniotic fluid of the embryonated eggs. To determine weights and lengths (where appropriate) of the studied organs and tissues, four embryonated eggs and poults per treatment were selected at 24E and at hatch. While the BCAAb decreased the YS and embryo weight, hatchability and the liver L* value, it increased the weight and quality of poults and the weights of breast and thigh muscles at hatch. In conclusion, the in ovo feeding of the BCAA blend negatively affected hatchability but positively affected hatching weight and poult quality by improving development of skeletal muscles and by regulating energy metabolism.  相似文献   
5.
Fusarium oxysporum f. sp. melongenae (Fomg), causal agent of Fusarium wilt of eggplant, is a serious pathogen in open fields and greenhouses. Inter-simple sequence repeat (ISSR) banding profiles, sequence analyses of inter-transcribed-spacer (ITS), translation elongation factor 1-alpha (TEF-1α), and actin (actA) DNA regions were employed in this study to determine genetic diversity and population structure of Fomg isolates obtained from Turkey. For ISSR study, (ACTG)5, (GACAC)3, (GACA)4, (GATA)4, HVH(TG)7 and (CA)8RG primers were selected from a set of 16. Discriminative ability of the primers revealed with various indices including polymorphic information content (PIC), and mean PIC value was calculated as 0.26. The ISSR data revealed 31 loci belonging to 202 Fomg isolates and 14 of them were found to be polymorphic. The isolates on neighbor joining ISSR tree were grouped into two major clusters which separated Fomg and outgroup isolates. Population structure was investigated based on bayesian modeling and results indicated five subpopulations (K = 5, ?K = 205.42). Mean genetic and geographical distances among sampling locations revealed only a weak and insignificant correlation (r = 0.583, P = 0.06). Phylogenetic analyses were carried out with ITS, TEF-1α and actA DNA regions with a selected subset of 30 Fomg, along with one non-host and one outgroup isolates. Since ITS region were not able to provide a meaningful separation, TEF-1α and actA sequences of each organism were concatenated individually to build a dendrogram. The clustering tree successfully separated the Fomg, non-host and outgroup isolates in which all Fomg were located on the same branch, forming a monophyletic group in the dendrogram.  相似文献   
6.
A nutrition trial with striped catfish (Pangasianodon hypophthalmus) juveniles was undertaken to evaluate the effect of replacing dietary fishmeal (FM) protein with corn gluten meal (CGM). A diet with FM as the main protein source was used as the control diet (FM). Five experimental diets (approximately 320 g kg?1 crude protein) were formulated to progressively replace 20% (CGM20), 40% (CGM40), 60% (CGM60), 80% (CGM80) and 100% (CGM100) of FM protein. Fifteen fish per tank (initial weight 11.2 ± 0.6 g) were randomly distributed into 18 80‐litre fibreglass tanks connected to a closed recirculation system (temperature 30.3 ± 1.0 °C). The diets were tested in triplicate for 12 weeks. The final weight and specific growth rate (SGR) of fish fed diets CGM20, CGM40 and CGM60 were not significantly different compared to fish fed the FM diet. Feed intake (FI) tended to decrease with increasing dietary CGM level. Striped catfish fed FM, CGM20 and CGM40 had significantly lower feed conversion ratio (FCR) compared with fish fed CGM80 and CGM100 (< 0.05). The protein efficiency ratio (PER) of fish fed the CGM80 and CGM100 diets was significantly lower than those of all other treatments (< 0.05). Total ammonia‐nitrogen (TAN) excretion increased with elevated dietary CGM inclusion. The viscerosomatic index (VSI) of fish fed the CGM80 and CGM100 diets were significantly higher (< 0.05) than those of fish fed the other treatments. The crude lipid content in the final body composition of the striped catfish was elevated significantly with increasing dietary CGM levels. Fish fed the CGM80 and CGM100 diets displayed haematocrit levels significantly lower (< 0.05) than those fed the other diets. The haemoglobin content in fish was significantly higher in fish fed CGM20 and lower at CGM100 compared to fish fed the FM diet. The results of the present trial indicated that the optimum level of FM protein replacement with CGM determined by quadratic regression analysis was 25.1% on the basis of maximum SGR.  相似文献   
7.
Alternaria genus includes many plant pathogens on numerous hosts, causing leaf spots, rots and blights. Alternaria blight has been observed as one of the important fungal diseases of pistachio (Pistacia vera L.) as well as its wild relatives (P. terebinthus, P. lentiscus, P. khinjuk, P. atlantica, P. mutica) in Turkey. Alternaria species were sampled from Pistacia spp. hosts from different geographic regions in Turkey during field trips in late spring to early fall of 2013. Alternaria blight symptoms were observed mainly on fruits and rarely on leaves. Four hundred and twenty two of the isolates were morphologically defined as A. alternata, A. tenuissima, A. arborescens and also intermediate morpho-species between A. alternata/A. arborescens. Pathogenicity of the isolates was confirmed with host inoculations on detached fruits. Mating types of 270 isolates of Alternaria spp. from the collection were identified using a PCR-based mating type assay that amplifies either a MAT1-1 or a MAT1-2 fragment from the mating locus. Although a strongly clonal population structure was expected due to the putative asexual reproduction of these fungi, both idiomorphs were detected at equal frequencies at several different spatial scales. The distribution of mating types within each geographic region, within host species as well as in overall collection was not significantly different from 1:1. Amplified fragments of partial idiomorph sequences were obtained for representative isolates. Parsimony trees were depicted based on sequence data of mating type genes for these representative isolates as well as some other Alternaria species obtained by Genebank. Several point mutations presented a few clusters which are supported by high bootsrapped values. The Alternaria blight disease agents both from cultivated and wild hosts were pathogenic on pistachio which may cause difficulties to control the disease because of extensity of pathogen sources. Besides, equal mating type distribution of the pathogen at both geographic and host species levels suggests a potential for sexual reproduction of Alternaria spp. in Turkey.  相似文献   
8.
The effect of varying hydrogel (0, 0.5, and 1.0% w/w) supply on some agro-physiological properties, such as dry matter, nutrient contents, chlorophyll contents, proline content, and ionic balance of bean plants in different salt sources and stress due to doses were investigated. Plants were treated with eight salt sources [sodium chloride (NaCl), sodium sulfate (Na2SO4), calcium chloride (CaCl2), calcium sulfate (CaSO4), potassium chloride (KCl), potassium sulfate (K2SO4), magnesium chloride (MgCl2), magnesium sulfate (MgSO4)] and four concentrations (0, 30, 60, and 120 mM doses) for 60 days in a growth media. Salt type, doses, and hydrogel (HG) affected the soil electrical conductivity. Soil salinity affected the parameters considered, and changed the nutrient balance of plants. High salt concentration caused substantial reduction in plant growth. Different salt concentrations negatively affected plant dry weight. The highest decrease of plant root dry weight was obtained with NaCl application followed by Na2SO4, CaCl2, CaSO4, MgCl2, MgSO4, KCl, and K2SO4, and similarly NaCl, Na2SO4, CaCl2, CaSO4, KCl, K2SO4, MgCl2, and MgSO4 in root dry weight. Total chlorophyll and nitrate contents of plants decreased with increasing salt doses, and the lowest value was obtained for NaCl application. Proline contents of plants were increased with increasing salt doses, and the highest value was obtained with the NaCl application. The effects of salt concentrations in nitrogen (N), potassium (K), and phosphorus (P) content of plants were significant. The presence of salt in the growth medium induced an important decrease the macro nutrient of the root and shoot part of plant such as N, P, K, calcium (Ca), and magnesium (Mg) content, but the N and P content of root and shoot part of the plant were increased with increasing of the HG application doses. The highest N and P increases were obtained with the 1.0 HG application for all salt types for both the root and shoots of plants. The HG added to saline soil significantly improved the variables affected by high salinity and also increased plant N and P, reduced soil electricity conductivity, nitrate, proline, and electrolyte leakage of plants, enhanced plant root and shoot dry weight by allowing nutrients and water to release to the plant as needed. The results suggested that HG has great potential for use in alleviating salinity stress on plant growth and growth parameters in saline soils of arid and semi-arid areas. This HG appears to be highly effective for use as a soil conditioner in vegetable growing, to improve crop tolerance and growth in saline conditions. It is intended to confirm the results of these studies by field trials.  相似文献   
9.
To evaluate the effect of reduced calcium (Ca) and available P (aP) levels in starter diets on growth performance and tibia, sternum and serum characteristics, and to assay the association between Ca and P (aP) intakes and these variables, 600 one-day-old broiler chicks (Ross 308) were used in a 21-days trial. Broilers were randomly allotted to five treatments with five replicate pens. Chicks were fed on one of the five starter diets that were formulated with a 10% reduction in the Ca and aP contents, starting from the control diet and hence, named as C (0.96% Ca, 0.45% aP), L1 (0.85% Ca and 0.42% aP), L2 (0.77% Ca and 0.38% aP), L3 (0.68% Ca and 0.34% aP) and L4 (0.61% Ca and 0.31% aP). Declining dietary Ca and aP levels did not affect body weight and levels of Ca, P and alkaline phosphatase in serum, but reduced linearly feed intake, the feed conversion ratio and the bone weight and ash content. The Ca and aP intakes and Ca:aP ratio displayed a positive correlation with both tibia and sternum weights, and the mass of the bones were equally sensitive to dietary Ca and aP levels. In conclusion, the body weight of young broilers was irresponsive to changes in the skeleton when exposed to early dietary Ca and aP restrictions (up to 0.61% Ca and 0.31% aP) and the mechanostat had limits due to the association between Ca and aP intakes, and bone properties.  相似文献   
10.
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