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A 12‐week feeding trial was conducted to evaluate the effects of replacing fishmeal (FM) with soybean meal (SBM), rapeseed meal (RM) and cottonseed meal (CSM) on growth, feed utilization and body composition of juvenile hybrid sturgeon Acipenser baerii ♀ × Acipenser schrenckii ♂ (initial body weight, 8.63 ± 0.24 g). Five isonitrogenous and isoenergetic diets were formulated as follows: a control diet (FM60) containing 600 g/kg FM and four other diets (FM45, FM30, FM15 and FM0 containing 450, 300, 150 and 0 g/kg FM, respectively) where protein from FM was substituted by a mixture of SBM, RM and CSM. Fish fed FM0 and FM15 had poorer growth performance, feed utilization, apparent digestibility coefficients of dry matter, protein, lipid and gross energy, and fed FM0 had poorer hepatosomatic index and survival compared with the fish fed FM60. The whole body lipid in fish fed FM0 was significantly higher than that in fish fed FM60 and FM15. This study indicates that 300 g/kg of FM can be replaced with a mixture of SBM, RM and CSM in the diet of juvenile hybrid sturgeon without compromising growth performance, feed utilization and body composition.  相似文献   
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为了研究ABA调控下冬小麦在蛋白质水平上的抗寒分子机制,以强抗寒冬小麦品种东农冬麦1号为材料,在外源ABA及氟啶酮处理后,于大田自然降温至4 ℃和-25 ℃时取分蘖节进行蛋白质双向电泳分析。对各处理组的双向电泳结果进行软件分析可知,4 ℃下得到可匹配的蛋白点587个,-25 ℃下得到可匹配蛋白点394个。筛选后选择差异显著的24个蛋白点进行质谱分析, 经鉴定这些蛋白包括逆境蛋白(WCI16、LTR-Rbps、CORs)、代谢相关蛋白(PGAM、PGK、26sRP、ATPase-β、GST1、GST、GSTF5)、转录翻译相关蛋白(BTFs、 eIF4A、eIF5A)和未知蛋白。  相似文献   
4.
Cuticular proteins(CPs) are major components of the insect cuticle-associated organs such as integument and wings, although the importance of CPs for wing development and function in hemimetabolous insects remains understudied. In the present study, a wing cuticular protein LmACP8 was identified from Locusta migratoria, which belongs to the RR-2 subfamily of cuticular protein RR consensus(CPR) chitin-binding proteins. LmACP8 was mainly expressed in the wing pads and showed high expression levels before ecdysis of third-, fourth-, and fifth-instar nymphs, with its encoded protein located in the procuticle of wing pads and adult wings. Depletion of LmACP8 by RNA interference markedly reduced the amount of its protein, which consequently caused abnormal wing morphogenesis in the transition from nymph to adult of L. migratoria. We further demonstrated that the abnormal morphogenesis was caused by severe damage of the endocuticle in the wings. LmACP8 was suppressed by 20-hydroxyecdysone(20 E) in vivo, however, its expression was significantly up-regulated after knocking down the hormone receptor gene LmHR39. Thus, the LmACP8 that is negatively regulated by the LmHR39-mediated 20 E signaling pathway is involved in wing development during the nymph to adult transition.  相似文献   
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Corn gluten meal (CGM), pea protein isolate (PPI) and their mixture (CPP, 1:1 ratio) were evaluated as fishmeal (FM) alternatives in black sea bream (Acanthopagrus schlegelii) juveniles (9.02 ± 0.12 g). A FM diet was designed as control, and other six diets had 20% and 40% FM protein replaced by CGM, PPI and CPP, respectively, with the supplementation of crystalline methionine, arginine and lysine. After the 8‐week feeding trial, significantly lower weight gain was found in fish fed the 40% CGM diet (p < .05), whereas other treatments had no statistical difference (p > .05). The values of feed efficiency ratio and feed intake, as well as proximate compositions of muscle and whole body, were not significantly influenced in all treatments. Apparent digestibility coefficients (ADCs) of dry matter, crude protein, threonine, valine, methionine, isoleucine, leucine, phenylalanine and lysine were significantly influenced by protein source. Fish fed the 40% CGM diet had significantly higher content of essential amino acid in muscle than that of the 20% PPI diet. Fish fed the 40% CGM diet had significantly lower content of serum cholesterol than other treatments (p < .05). Elevated serum superoxide dismutase activity was found in fish fed the 40% plant protein diets. In conclusion, between 20% and 40% FM protein could be replaced by CGM, while about 40% FM protein derived from PPI and CPP could be applied in black sea bream.  相似文献   
7.
正小麦蓝矮病(Wheat blue dwarf,WBD)是我国西北麦区一种重要植原体病害,在我国西部地区危害严重。该病害由异沙叶蝉(Psammotettix alienus L.)专化性传播,介体传毒成为病害流行的重要中心环节[1]。本实验室前期通过免疫荧光标记研究发现WBD植原体免疫膜蛋白(immunodominant membrane protein, IMP)与介体异沙叶蝉肌动蛋白互作,说明IMP在植原体传播和致病过程中起关键作用。  相似文献   
8.
Clostridium autoethanogenum protein (CAP) is a single‐cell protein derived from ethanol production and may have potential to become a substitute for fishmeal in aquafeeds. A 70‐day feeding trial was conducted with black sea bream (Acanthopagrus schlegelii) (mean initial weight 6.03 ± 0.09 g) to evaluate partial replacement of fishmeal with CAP in diets. Seven isonitrogenous and isoenergetic diets were formulated with graded levels of CAP (0, 4.85, 9.70, 14.55, 19.40, 38.80 and 58.20%) to replace fishmeal. The inclusion of CAP at all dietary levels tested did not significantly affect the growth performance (p > .05). Fish fed the CAP58.20% diet showed a significantly lower feeding rate, with significantly higher protein efficiency ratio and feed efficiency ratio compared with fish fed the other diets (p < .05). No statistical differences were found in dorsal muscle and whole‐body compositions. Total superoxide dismutase in serum of fish fed CAP58.20% diet was significantly lower compared with that of the control. Malondialdehyde, catalase, total antioxidant capacity and digestive enzyme activities revealed no significant differences among dietary treatments. Phosphorus retention efficiency significantly increased, and phosphorus discharge showed a downward trend with increasing CAP inclusion levels. In conclusion, the results indicated that CAP is a safe and effective alternative protein source, which can replace fishmeal in the diet of black sea bream up to 58.20%, without adverse effects on growth performance, antioxidation and digestive enzyme activity. This study has shown the potential of converting industrial waste into a high protein feed ingredient for aquafeeds.  相似文献   
9.
The pomaces obtained after cold pressing oil production from oil seeds can be regarded as a source of many valuable nutrients such as unsaturated fatty acids, dietary fibre and antioxidants. The aim of the research was to determine the effect of five oil pomaces from black seed, hemp, pumpkin, milk thistle and primrose on the structure of gluten proteins. The model dough was supplemented with 3%, 6%, and 9% of the pomaces. Structural changes in gluten proteins were studied using Fourier transform Raman spectroscopy (FT-Raman) and Fourier transform infrared spectroscopy (FT-IR). Additionally, chemical composition of the pomaces was determined. Changes observed in the gluten structure resulting from the model dough supplementation with oil pomaces allow the pomace to be divided into two groups depending on the type and amount of fatty acids present in the pomaces. If the pomace contains a low number of fatty acids (black seed and pumpkin), pseudo-β-sheets are formed from β-turns and antiparallel-β-sheets in the gluten network. If the pomace contains a high number of fatty acids, non-aggregated β-structures are observed. Although the pomaces contain considerable amount of dietary fibre and polyphenols, comparison of the observed structural changes in gluten network with pomaces’ chemical composition indicates that the changes are connected with presence of fatty acids.  相似文献   
10.
新疆褐牛不同部位肉宰后成熟过程中蛋白降解变化研究   总被引:3,自引:0,他引:3  
为研究肌纤维类型对新疆褐牛肉宰后成熟过程中蛋白质降解变化的影响,选取背最长肌、腰大肌和股二头肌3个不同肌纤维类型组成的部位肉,分别在宰后4℃成熟1 h、6 h、12 h、1 d、3 d、7 d、14 d研究其蛋白质溶解度、肌原纤维小片化指数、肌纤维超微结构变化及进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)分析。结果表明:不同肌纤维类型的新疆褐牛肉蛋白质降解模式差异较大,Ⅰ型肌纤维含量高的腰大肌比Ⅱ型肌纤维含量高的背最长肌和股二头肌具有更高的初始肌原纤维小片化指数(MFI),但肌原纤维降解的速度比背最长肌和股二头肌要慢。ⅡA型肌纤维含量与初始蛋白质溶解度呈显著正相关,与蛋白质溶解度的变化率显著负相关。不同肌纤维类型组成的新疆褐牛肉在宰后成熟过程中蛋白质降解变化存在差异,研究结果可为宰后成熟过程合理控制、新疆褐牛肉产品开发提供理论依据。  相似文献   
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