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1.
Four isonitrogenous diets containing different carbohydrate:lipid (CHO:L) ratios (0.3, 0.6, 1.1 and 1.8) were tested in triplicate groups (16 fish per replicate) of silvery‐black porgy juveniles for 8 weeks. Growth performance was not affected by different dietary CHO:L ratios (P > 0.05); however, the viscerosomatic index, the intraperitoneal fat, whole‐body lipid, energy and n‐3 long chain polyunsaturated fatty acids levels increased with decreasing dietary CHO:L ratios (P < 0.05). Fish fed with 1.8 CHO:L diet had the lowest apparent digestibility coefficients of protein and lipid, as well as the lowest plasma haemolytic and lysozyme activities (< 0.05). Red blood cell counts and plasma glucose levels were higher in fish fed with 1.1 and 1.8 CHO:L ratio diets than in the other groups (< 0.05). Plasma alkaline phosphatase and alanine aminotransferase, as well as the level of lipid peroxidation and total antioxidant capacity in the liver and plasma increased as dietary CHO:L ratios decreased (< 0.05). The results of the current study indicated that the diets with CHO:L ratios between 0.6 and 1.1 are optimal for silvery‐black porgy, whereas higher ratios may result in hyperglycaemia and immune suppression, and lower CHO:L ratios may lead to oxidative stress and liver dysfunction.  相似文献   
2.
A 5‐week study was performed to evaluate the effect of spoilage date extract (SDE) as the biofloc carbon source on Litopenaeus vannamei (5.4 ± 0.3 g) performance. The two levels of dietary protein (15% and 25% crude protein) and two carbohydrate sources (molasses‐M and SDE‐P) were tested including: M15, M25, P15 and P25. The minimum (0.2 ± 0.0 mg/L) and the maximum (0.5 ± 0.0 mg/L) of total ammonia nitrogen were observed in the P15 and M25 groups respectively. The highest protein efficiency ratio (6.1 ± 0.3) and protein productive value (112.3 ± 5.8%) were found in the P15 group (p < 0.05). No significant difference was found between biofloc treatments in the expression of cathepsin L gene in hepatopancreas (p > 0.05). The number of total haemocyte count (THC), semigranular cells (SGC) and granular cells (GC) of shrimp in SDE‐based biofloc treatments was relatively higher than those in molasses‐based biofloc treatments. Following the white spot syndrome virus (WSSV) challenge, a significant decrease in THC, SGC, GC and hyaline cell values was observed in all treatments (p = 0.001). Plasma biochemical parameters were significantly influenced by dietary protein levels, biofloc carbon sources as well as WSSV challenge test. In conclusion, SDE successfully could be used as an alternative carbon source for establishing a biofloc system in L. vannamei production.  相似文献   
3.
Zusammenfassung Die wichtigsten Milben von wirtschaftlicher Bedeutung im Libanon, Jordanien und der südlichen Türkei werden aufgeführt. Es handelt sich auf Äpfeln um:Tetranychus urticae, Metatetranychus ulmi, Tetranychus cinnabarinus, Bryobia rubrioculus; aufCitrus sp. um:Phyllocoptruta oleivora, Aceria sheldoni ,Eutetranychus orientalis, Brevipalpus obovatus, T. cinnabarinus: auf Gemüsearten um:Tetranychus urticae, T. cinnabarinus; auf Wein um:Eriophyes vitis; auf Granatäpfeln um:Eriophyes granati.Die Orte und Daten der Befunde werden angegeben.
Summary The mites of economic importance in the Lebanons, Jordan and South-Turkey are listed with the dates and places in which they were found. On apples were found:Tetranychus urticae, Metatetranychus ulmi, Tetranychus cinnabarinus, Bryobia rubrioculus; onCitrus sp.: Phyllocoptruta oleivora, Aceria sheldoni, Eutetranychus orientalis, Brevipalpus obovatus, T. cinnabarinus; on vegetables:T. cinnabarinus, Tetranychus urticae; on vines:Eriophyes vitis; on pomegranates:Eriophyes granati.

Résumé Les acariens d'une importance èconomique au Liban, en Jordanie et au sud de la Turquie sont donné avec les dates et les endroits où ils ont ètè trouvés. Sur pommiers on a trouvé:Tetranychus urticae, Metatetranychus ulmi, Tetranychus cinnabarinus, Bryobia rubrioculus; sur agrumes:Phyllocoptruta oleivora, Aceria sheldoni, Eutetranychus orientalis, Brevipalpus obovatus, T. cinnabarinus; sur légumes;Tetranychus urticae, T. cinnabarinus; sur les vignes:Eriophyes vitis; sur les grenades:Eriophyes granati.
  相似文献   
4.
  • ? In this study, longitudinal specific modulus of elasticity along the grain (specific MOEL = MOEL/ρ) as well as radial and tangential shear moduli (G LR and (G LT ) of Populus Deltoides wood were examined in free flexural vibration in a free-free bar method, where end-cracks produced manually in LT plane along and parallel to annual rings in four different sizes.
  • ? The effects of four different crack sizes (0, 6, 12, and 18 cm) on elastic parameters of the bars were examined for their vibration properties based on Timoshenko bar equations, in order to find a procedure to make a confident choice of a clear specimen among the cracked ones, considering three initial modes of vibration.
  • ? Based on research findings, a significant correlation existed between radial and tangential shear moduli of the clear bars as G LR was approximately 15 percents higher than (G LT . After making the shortest crack sizes, however, this correlation entirely faded. Statistically for 6 cm crack, decreases in specific MOE L for measurement on the tangential impact were not significant though they were for longer cracks.
  • ? It was also revealed that in specimen under the study if longitudinal specific modulus of elasticity from both LR and LT flexural vibrations were almost equal and G LR was slightly larger than (G LT , the user could be confident enough to consider the specimen without severe longitudinal cracks.
  •   相似文献   
    5.
    6.
    The present research was designed to investigate the growth promoting and immunostimulating properties of Moringa oleferia leaf meal (MLM) in grass carp. Juvenile grass carp (22.03 g ± 1.164) were fed with diets supplemented with 0, 50, 100 and 150 g/kg MLM for 48 days. At the end of feeding trial, skin mucus was used for analysis of lysozyme, protease, antiprotease and peroxidase activity. Head kidney was used for expression analysis of tumour necrosis factor‐alpha, interleukin‐8 and interferon‐γ. The obtained results showed that fish fed with 100 and 150 g/kg MLM had significant increase in weight gain and specific growth rate (p < .05). However, condition factor was not altered. The MLM (50 and 100 g/kg) inclusion resulted in higher mucus lysozyme and protease activity (p < .05), while peroxidase activity increased only in fish fed with 100 g/kg MLM and antiprotease activity was not altered. Expression of tnf‐α increased in a dose‐dependent manner, and significant (p < .05) increase was recorded in fish fed with 150 g/kg MLM. The expression of il‐8 and ifn‐γ increased in fish fed with 50 and 150 g/kg MLM; however, the increase was not significant (p > .05). In conclusion, supplementing juvenile grass carp feed with MLM up to 150 g/kg has growth promoting and immunostimulating effects.  相似文献   
    7.
    Y. Kowyama  T. Saba  T. Tsuji  T. Kawase 《Euphytica》1994,80(1-2):27-38
    Summary Developmental stages during gametogenesis of rice were histologically examined in the period from differentiation of reproductive organs to anthesis. Plants were exposed to acute X-rays of 20 Gy. Radiosensitivity and mutation frequency were investigated in relation to the developmental stages of reproductive organs. The most radiosensitive stage, as measured by reduction of the M1 pollen-and seed-fertilities, was the last premeiotic interphase. Mutations induced at different developmental stages were scored in M3 strains. Sterility mutants and short-culm mutants were most frequently observed. Grain shape, panicle morphology, heading-date and endosperm character mutants were induced at a relatively low frequency. The overall mutation frequency varied with the developmental stage at the time of irradiation. The highest overall mutation frequency was observed when radiation was applied 10 days before anthesis, the late tetrad stage of microspores. Radiation exposure of florets at the late tetrad stage was found to be a more efficient method of inducing a large number of mutations than radiations applied to seeds and fertilized egg cells.  相似文献   
    8.
    Sirt5 is a NAD-dependent protein lysine demalonylase and desuccinylase   总被引:1,自引:0,他引:1  
    Du J  Zhou Y  Su X  Yu JJ  Khan S  Jiang H  Kim J  Woo J  Kim JH  Choi BH  He B  Chen W  Zhang S  Cerione RA  Auwerx J  Hao Q  Lin H 《Science (New York, N.Y.)》2011,334(6057):806-809
    Silent information regulator 2 (Sir2) proteins (sirtuins) are nicotinamide adenine dinucleotide-dependent deacetylases that regulate important biological processes. Mammals have seven sirtuins, Sirt1 to Sirt7. Four of them (Sirt4 to Sirt7) have no detectable or very weak deacetylase activity. We found that Sirt5 is an efficient protein lysine desuccinylase and demalonylase in vitro. The preference for succinyl and malonyl groups was explained by the presence of an arginine residue (Arg(105)) and tyrosine residue (Tyr(102)) in the acyl pocket of Sirt5. Several mammalian proteins were identified with mass spectrometry to have succinyl or malonyl lysine modifications. Deletion of Sirt5 in mice appeared to increase the level of succinylation on carbamoyl phosphate synthase 1, which is a known target of Sirt5. Thus, protein lysine succinylation may represent a posttranslational modification that can be reversed by Sirt5 in vivo.  相似文献   
    9.
    1. This study aimed to evaluate the effects of dietary medium-chain fatty acids (MCFAs) on the performance, carcass characteristics, and some serum parameters of broiler chickens.

    2. A total of 176 one-day-old male broiler chicks (Ross 308) were assigned to four treatments including control treatment (basal diet), 0.1% MCFA, 0.2% MCFA, and 0.3% MCFA treatments according to a completely randomised design. Each treatment consisted of 4 replicates with 11 chicks for each replicate. In MCFA treatments, the amounts of MCFAs were added to basal diet as a substitution of soybean oil.

    3. There were not any significant differences in body weight, feed intake, and feed conversion ratio among the treatments in different stages of the experiment. However, MCFA treatments had a lower abdominal fat and a higher breast yield compared to control treatment.

    4. Blood glucose, cholesterol, and low-density lipoprotein (LDL)-cholesterol concentrations were significantly decreased, but blood high-density lipoprotein (HDL)-cholesterol concentration was significantly increased in the MCFA treatments compared to the control treatment.

    5. These results indicate that dietary MCFA has a positive effect on the health and productivity of broiler chickens.  相似文献   

    10.
    In Japan, tea (Camellia sinenis (L.) Kuntze) seedlings are propagated by cutting. A root system of clonal plants by cutting consists of adventitious roots and lateral roots. Most of the roots grow horizontally, which results in a shallow distribution of the root system. Such a shallow root system could be one of the factors contributing to the deterioration of nutrient uptake and resistance to water stress. Gravitropism of the roots is considered to be a decisive factor that controls the depth of a root system. The authors have investigated changes in the growth direction of roots to gravitative stimulus, using several kinds of roots (seminal roots, lateral roots and adventitious roots). Furthermore, amyloplasts in the root-cap cells, which are considered to be an equipment sensing gravistimulus, were observed. Seminal roots prominently showed orthogravitropism and contained many amyloplast particles in their root cap cells. Most lateral and adventitious roots showed plagiogravitropism, growing in an angle to gravistimulus, and lacked observable amyloplast particles in their root cap cells. The results suggest that the shallowing of root systems of elonal tea plants could be attributed to a gravitropic reaction of the adventitious and lateral roots composing the root system. There could also be a close relationship between the growth direction of roots and the presence of amyloplasts in root-cap cells.  相似文献   
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