Preparation by enzymolysis and bioactivity of iron complex of fish protein hydrolysate (Fe-FPH) from low value fish

Preparation of Fe^2＋ chelate of fish protein hydrolysate （Fe-FPH） obtained from low value fish proteins was introduced and its bioactivity was studied by compound enzymolysis. The optimum conditions for hydrolysate chelating Fe^2＋ are DH （degree of hydrolysis） at 5%, pH 7.0, 20℃ and 15 min chelating time for FM （material not being defatted）. Four types of Fe-FPH including CA （deposit after chelating）, CB （deposit in 50% of absolute ethanol solution）, CC （suspended deposit in 80% of absolute ethanol solution）, and CD （bottom deposit in 80% of absolute ethanol solution） were fractionated with absolute ethanol from FM. Structural analysis through infra-red spectrum revealed that Fe^2＋ was combined strongly with amino-group and carboxyl-group in each chelate and each Fe^2＋ could form two five-member ring structures. All of the four chelates were shown more significant antioxidative activity and can be used as natural hydrophobic and hydrophilic antioxidant. Among all the chelates, the CB possesses the most effective antioxidative activity at 92% as high as that of a-tocopherol. Among all Fe-FPHs, only CD showed the most effective antibacterial activity against Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Bacillus subtilis and can be used as natural antibacterial. It provides a more effective way for utilization of low value fish proteins and key information of Fe-FPH as additive in food industry.

Fish Protein Recovered Using pH Shifting Method and Its Physicochemical Properties

The solubility of meat protein of croaker and jack mackerel was significantly affected by pH shifting. The protein yield of alkali-aided processing is higher than those of conventional and acid-aided processing. The addition of sarcoplasmic protein increases the breaking force and deformation value. The breaking force of recovered protein gel from alkali-aided processing is decreased by the addition of NaCI. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE） revealed that fish protein of alkali is similar to that at pH7.0. Alkali-aided processing for recovering fish protein is a valuable method for increasing the utilization of frozen and pelagic fishes and for making kamaboko products.

Improvement of Vitis amurensis Rupr.grape quality by using fish protein hydrolysates as fertilizer

High quality wine grape is the first factor to satisfy the wine-maker to produce superior quality wines.In this work,a fish protein hydrolysates derived from deep-sea salmon or cod,was used as fertilizer to improve Shuanghong(Vitis amurensis Rupr.)grape quality.Application of powder fish protein hydrolysates fertilizer by spraying directly to foliar(4.5 kg/ha),to root(4.5 kg/ha)or to the both foliar(4.5 kg/ha)and root(4.5 kg/ha)were carried out respectively,during the period from 2–3 weeks before flowering until 2–3 weeks before harvest.Grape sampling was made at both veraison and harvest.Different classes of phenolic compounds,including 10 phenolic acids and 11 proanthocyanidins in grape seeds and 10 anthocyanins in grape skins were determined by UHPLC or HPLC;total anthocyanins and total polyphenols in grape skins were determined by spectrophotometric method.Antioxidant activities of the phenolic compounds were evaluated by ABTS and FRAP methods.The results showed that the application of fish protein hydrolysates fertilizer to both root and foliar led to a significant improvement of berry quality at harvest/maturity,i.e.,increasing 12.13%total polyphenols(TP),8.3%total anthocyanins 11.03%ABTS and 45.81%FRAP compared with control.Besides,both root and foliar application resulted in the highest individual anthocyanins and proanthocyanidins in grapes.These results suggest that the both root and foliar application could be of great interest for the viticulturists to produce grapes with higher polyphenolic content and antioxidant activity.Although this work was experimented with Vitis amurensis Rupr.grapes,the proposed methods would also be applicable to other grape varieties for the purposes of increasing anthocyanin or polyphenol contents.

Effects of fish protein hydrolysate on growth performance and humoral immune response in large yellow croaker (Pseudosciaena crocea R.)

We investigated the effects of fish protein hydrolysate (FPH) on growth performance and humoral immune response of the large yellow croaker (Pseudosciaena crocea R.). One thousand and two hundred large yellow croakers [initial average weight: (162.75±23.85) g] were divided into four groups and reared in floating sea cages (3 m×3 m×3 m). The animals were fed with 4 diets: basal diet only (control) or diets supplemented with 5%, 10% and 15% (w/w) FPH. The results show that dietary FPH levels significantly influenced the growth and immunity of the large yellow croaker. Compared with the control group, total weight gain (TWG) in all treatment groups, relative weight gain (RWG) and specific growth rate (SGR) in fish fed with diets supplemented with 10% and 15% FPH were significantly increased (P<0.05). Similar results were observed in immune parameters [lysozyme activity, serum complements, immunoglobulin M (IgM)]. Lysozyme activity, complement C4 and IgM were also significantly increased (P<0.05) in fish fed with diets supplemented with 10% and 15% FPH, while complement C3 level was significantly increased (P<0.05) in all treatment groups. In general, with the supplementation of FPH, particularly at dose of 10%, the growth performance and immunity of the large yellow croaker can be improved effectively.

Identification of SNARE proteins in fish—Tilapia Oreochromis niloticus

SNARE proteins are a group of membrane-associated proteins involved in exocytosis, secretion and membrane trafficking events in eukaryotic cells. Research on SNARE protein biology has become a more attractive field in recent years, which is applied to marine biology specifically to the fish Tilapia （Oreochromis niloticus）. Plasma membrane fractions of different tissues of Tilapia, including brain, liver-pancreas, intestine, skin and muscle, were extracted, and immuno-decorated with isoform-specific antibodies to the SNARE families and associated proteins. The presence of Syntaxins - 1 A, 2 and 3, SNAP - 23 and SNAP - 25, VAMP - 2, Munc - 18 - 1 and Munc - 13 in the brain was identified, which were differentially distributed in the other organ tissues of the fish Tilapia. The distinct distribution of SNARE and associated proteins will serve as the basis for further investigation into their special secretory function in these tissues of the fish.

Amino acid fortified diets for weanling pigs replacing fish meal and whey protein concentrate:Effects on growth,immune status,and gut health

Background： Limited availability of fish meal and whey protein concentrate increases overall feed costs. Availability of increased number of supplemental amino acids including Lys, Met, Thr, Trp, Val, and lie allows replacing expensive protein supplements to reduce feed costs. This study was to evaluate the effect of replacing fish meal and/or whey protein concentrate in nursery diets with 6 supplemental amino acids on growth performance and gut health of post-weaning pigs. Treatments were 1） FM-WPC： diet with fish meal （FM） and whey protein concentrate （WPC）; 2） FM-AA： diet with FM and crystalline amino acids （L-Lys, L-Thr, L-Trp, DL-Met, L-Val, and L-lie）; 3） WPC-AA： diet with WPC and crystalline amino acid; and 4） AA： diet with crystalline amino acid. Results： Pigs in FM-AA, WPC-AA, and AA had greater （P 〈 0.0.5） ADG and gain：feed than pigs in FM-WPC during wk ] （phase 1）. Plasma insulin concentration of pigs in AA tended to be greater （P = 0.064） than that of FM-WPC at the end of wk 1 （phase 1）. Plasma concentrations of IgG in AA was lower （P 〈 0.05） compared with WPC-AA and FW, and FM-AA had lower （P 〈 0.05） IgG concentration than WPC-AA at the end of wk 1 （phase 1）. Concentration of acetate in cecum digesta in FM-AA tended to be greater （P = 0.054） than that of FM-WPC and WPC-AA. Concentration of isovalerate in cecum digesta of pigs in FM-AA was greater （P 〈 0.05） than that of FW and WPC-AA. Conclusions： This study indicates that use of 6 supplemental amino acids can replace fish meal and/or whey protein concentrate without adverse effects on growth performance, immune status, and gut health of pigs at d 21 to 49 of age. Positive response with the use of 6 supplemental amino acids in growth during the first week of post-weaning may due to increased plasma insulin potentially improving uptake of nutrients for protein synthesis and energy utilization. The replacement of fish meal and/or whey protein concentrate with 6 supplemental amino acids could decrease the crude protein level in nursery diets, and potentially lead to substantial cost savings in expensive nursery diets.

FISH和IHC检测HER2基因及蛋白在乳腺癌诊治中的应用

目的对比研究免疫组织化学（IHC）与荧光原位杂交（FISH）方法检测乳腺癌中C-erbB-2蛋白表达和HER2基因扩增,评估两种方法的实际应用价值。方法 IHC和FISH法分别检测58例乳腺癌组织中C-erbB-2蛋白表达和HER2基因扩增状况,并进行一致性分析。结果IHC检测蛋白阳性2＋和3＋共22例,占总病例的37.9%,58例乳腺癌中FISH检测出HER2基因扩增17例,占29.3%。IHC检测C-erbB-2蛋白3＋的12例中11例HER2基因扩增阳性,1例无扩增;C-erbB-2蛋白2＋者10例,其中5例可见HER2基因扩增;C-erbB-2蛋白1＋者11例HER2基因扩增仅1例。C-erbB-2蛋白阴性病例共25例均未检测到基因扩增。结果显示IHC检测C-erbB-2蛋白与FISH检测HER2基因扩增状态有较高的一致性（k=0.681,P〈0.01）,C-erbB-2蛋白阴性和3＋标本与HER2基因扩增阳性率比较差异无统计学意义（P〉0.05）;而C-erbB-2蛋白1＋和2＋病例与其HER2基因扩增差异具有统计学意义（P〈0.05）。结果 IHC检测C-erbB-2蛋白强阳性（3＋）和阴性（0）与HER2基因扩增有较高的一致性,可作为临床是否应用Herceptin治疗的依据,而C-erbB-2蛋白2＋和1＋病例必须进一步行HER2基因扩增检测。

利用FISH技术检测胃癌组织中HER2基因及其与p53蛋白表达的相关性

目的探讨胃癌组织中HER2基因状态及其与p53蛋白表达的相关性。方法采用FISH和免疫组织化学技术对67例胃癌组织中HER2基因状态和p53蛋白进行了检测。结果 FISH检测HER2基因扩增率17.9%(12/67),HER2基因无扩增的55例中拷贝数增加和基因扩增者共49.3%(33/67)。HER2蛋白表达率43.3%(29/67),在HER2蛋白表达3+、2+者中HER2基因扩增比例分别为3/4和6/9与1+者3/16比较差异有统计学意义(P<0.05)。p53蛋白表达率58.2%(39/67),HER2基因扩增率、p53蛋白表达率与胃癌的浸润深度、淋巴结有无转移差异有显著性(P<0.05);与组织学类型、年龄、性别差异无统计学意义(P>0.05)。结论 HER2基因扩增率和基因拷贝数增加与p53蛋白表达率呈正相关,HER2基因状态和p53蛋白表达的联合检测对于胃癌的转移、患者的病情发展及预后评估有一定的参考价值,对指导临床制定个体化治疗方案有重要意义。

A Study of the Enzymatic Hydrolysis of Fish Frames Using Model Systems

A model system was employed to study the operating conditions and primary parameters of enzymic hydrolysis of cod proteins. Pancreatin, papain, and bromelain were used to hydrolyse minced cod fillets under controlled conditions and with the rate of hydrolysis being continually monitored via both the pH-stat and TNBS method. The two methods were compared and evaluated. The rate of protein solubilisation was plotted against the degree of hydrolysis (DH). Dry fish protein hydrolysate (FPH) powders having short, medium and high degrees of hydrolysis (DH of approximately 8%, 11% and 16% respectively) were produced and analysed for their molecular weight distribution, using size exclusion chromatography. Almost complete protein solubilisation (75 g soluble protein per kg hydrolysis solution) could be achieved within an hour, at 40oC, at 1% enzyme/substrate ratio (w/w) with papain and bromelain. The pH-stat was found capable of continuously following the rate of hydrolysis but only at low DH. The TNBS could be accurately used even at high DH to estimate the percentage of the peptide bonds cleaved, but required chemical analysis of withdrawn samples.

A Comparative Study of Present Status of Marketing of Formalin Treated Fishes in Six Districts of Bangladesh

The fish is an important food stuff and source of protein all over the world. In Bangladesh, fisheries sector contributes a lot, in the case of the earning foreign currency and meeting domestic need of the animal proteins. To fulfill the domestic need of protein and fish, Bangladesh imports fish and fish products from the neighboring county. In many studies, it was proved that most of the imported fishes are contaminated with formalin, which is the highly hazardous and carcinogenic chemical. Information was collected from the fish retailers and consumers on the marketing of the formalin treated fishes through survey using prescribed questionnaire at 18 different fish markets in 6 different districts of Bangladesh. It was found that most of the commercially imported fishes are highly contaminated with formalin. On the other hand, local big fishes, such as rui (Lobeo Rohita), catla (Catla catla) and mrigal (Cirrhinus cirrhosus) etc., are also formalin contaminated partially, but not all the fishes. All the local small fishes are free from the formalin contamination. In this study, it was found that, among the 939 fish samples collected from the different fish markets of the six districts, 213 fishes (22.68%) were directly contaminated with formalin. The contamination rate is so much higher in the big city like Dhaka (36.78%) and lower in the small town like Jamalpur districts (13.33%). This study also indicated that, all the village markets were totally free from the formalin contamination. As the fish traders used formalin to increase the shelf life of the fishes, it was also observed that, the shelf life of the local fishes or formalin free fishes was much higher and the organoleptic characteristics were much more excellent than the formalin contaminated local or imported fishes. The price of the imported fishes was also lower than the local fishes. It was also clear that, the organoleptic characteristics of the imported fishes and formalin contaminated fishes were greatly different than the local fishes, which were not satisfactory to the consumers. The study also indicated that, the overall hygienic practice and sanitary conditions of the markets and the fish traders/retailers were very poor, not satisfactory. This survey also revealed that, all the traders or retailers who were mixed formalin with the fishes, knew about the bad effects of the formalin.

大口黑鲈饲料营养需求及鱼粉替代研究进展

水产养殖动物的精准营养需求参数对其配合饲料的优化或者开发至关重要。文章概述了大口黑鲈蛋白质、脂肪、矿物质、碳水化合物以及维生素等主要元素需求以及蛋白源替代研究,对大口黑鲈饲料配制和降低成本等有重要的指导意义。

Utilization of Small Size Bolti (<i>Talibia nilotica</i>) and Sardine (<i>Sardina pilchardus</i>) Fish in Preparing Canned Weaning Food Purees

Utilize small size of bolti and sardine fish in preparing fish based weaning foods rich in protein, essential amino acids, fat high in omega 3 fatty acids, minerals and vitamins was investigated. The proximate composition, nutritional value, physical and sensorial properties were evaluated, The results of the chemical composition showed that the moisture content of fish based weaning food purees ranged from 67.73% to 72.05%. On dry weight basis, the five prepared formulations considered rich in protein (37.39% - 44.86%), fat (26.55% - 30.43%), ash (6.53% - 12.23%) and low in carbohydrates (20.70% - 22.18%). Using fish bones with muscles in preparing weaning food puree caused a marked rise in its content of Ca, P, Fe, and Zn levels especially in purees formulated from bolti. Weaning food purees containing sardine fish rich, in fat, were higher in vitamin A and D than those formulated from bolti one. Palmitic acid (C16:0), stearic acid (C18:0), and myristic acid (C14:0) represented the major saturated fatty acids in the prepared formulations. Weaning food purees containing sardine fish had relatively higher levels of sulfur-containing amino acids and slight lower values of lysine, alanine and glycine than these including bolti fish. The In vitro protein digestibility index (IVPDI) of the different formulations was found to be 100%. The visual colour of such products can be described as yellowish. Except hardness, the other texture characteristics;cohesiveness, springiness, gumminess, and chewiness of the weaning food purees did not significantly change. The children’s mothers accepted the appearance, flavor, and mouth feel of all weaning food purees prepared in this study.

Effects of Three Humic Acid Foliar Fertilizers on Quality and Photosynthetic Characteristics of Hawthorn

[Objectives]To investigate the effects of three foliar fertilizers on photosynthetic characteristics,fruit quality and yield of hawthorn.[Methods]Taking hawthorn foliar fertilization as the reference,the photosynthetic rate,transpiration rate,intercellular CO 2 concentration,stomatal conductance and single fruit weight of hawthorn leaves were measured under different concentrations of foliar fertilizer.[Results]The results showed that the photosynthetic rate,transpiration rate and stomatal conductance of hawthorn leaves increased significantly,while the intercellular CO 2 concentration decreased.Specifically,the fish protein peptide foliar fertilizer performed best,with net photosynthetic rate and transpiration rate increased by 57.22%and 57.51%,respectively.All the three foliar fertilizers significantly reduced the intercellular CO 2 concentration.In addition,fertilization significantly increased the single fruit weight of hawthorn,and the effect of fermented fulvic acid foliar fertilizer was the most significant,with the highest growth rate of 68.49%.[Conclusions]Spraying foliar fertilizer significantly increased the content of Vc,titratable acid,anthocyanin and soluble solids of hawthorn fruit,among which fermented fulvic acid foliar fertilizer had the optimal effect.

化肥减量配施鱼蛋白有机液肥对番茄产量和品质的影响

为探讨增施鱼蛋白有机液肥替代化肥的效果,以每667m^(2)施用高钾水溶肥5.0kg为对照,设置每667 m^(2)施用高钾水溶肥3.5 kg+鱼蛋白有机液肥5.0 L、高钾水溶肥2.0 kg+鱼蛋白有机液肥5.0 L、高钾水溶肥0.5kg+鱼蛋白有机液肥5.0L这3个化肥减量处理,比较分析化肥减量增施鱼蛋白有机液肥对番茄生长、产量和果实性状及可溶性固形物含量的影响。结果表明:在每667m^(2)施用5.0L鱼蛋白有机液肥的情况下,减少水溶肥用量会降低番茄的株高、叶长和叶宽,但促进了茎粗、果实纵横径的生长,其中不同处理的果实纵径差异不显著,果形指数和可溶性固形物含量随水溶肥用量的减少先升高再降低,以每667 m^(2)每次追施高钾水溶肥3.5 kg和2.0 kg的果形指数最大,但与其他处理没有显著差异。不同处理的平均单穗坐果数没有显著差异,单果质量和果实纵横径的变化趋势一致,每667 m^(2)每次追施高钾水溶肥0.5 kg的小区产量最大。因此,在追求产量的情况下,果实膨大至采收前以每667 m^(2)每次追施高钾水溶肥+0.5 kg鱼蛋白有机液肥5.0 L的肥料配比最适合生产;如果追求品质,每667 m^(2)每次追施高钾水溶肥2.0 kg+鱼蛋白有机液肥5.0 L的肥料配比有利于生产,比对照果实可溶性固形物含量可提高5.8%,667 m^(2)产量提高17.2%。

Influence of Amino Acid Supplementations in Juvenile Yellow Perch Fed Plant Protein Combinations

Distillers dried grains with solubles (DDGS) in combination with soy protein concentrate (SPC) with and without an essential amino acid (EAA) complex were assessed as protein alternatives in juvenile Yellow Perch Perca flavescens diets. Diets contained 5% FM, 40% SPC, and 20% or 40% DDGS each with or without EAA. No mortalities or health assessment differences were observed during the trial and all fish readily accepted the experimental diets. Diets supplemented with EAA produced greater weight gain, improved feed conversion, and apparent protein digestibility. Performance was consistently improved for fish fed diets containing amino acid supplements. Based on these results, Yellow Perch are able to utilize high levels of the plant proteins, accompanied with EAAs, as a FM replacer.

油炸预制鱼冷冻复热过程中的品质变化

为解决新零售预制烤鱼经冷冻复热后口感下降的问题,选取草鱼为研究对象,以水分含量、持水力、水分分布及组成和微观结构等为指标,探究鱼肉油炸、冷冻、复热不同阶段的品质变化规律。结果表明,随冻融循环次数增加,鱼肉肌纤维破坏程度增加,水分含量显著降低(P<0.05),持水性变差,脂肪氧化和蛋白降解程度显著增加(P<0.05),风味发生改变。复热后,冻融1次鱼肉仍能保持较好口感,但冻融2次后鱼肉感官评分较低,且肌原纤维小片化指数、TBARS和TCA-可溶性肽含量较冷冻前样品分别增加了24.44%、225.84%和52.85%。综上,当油炸预制鱼产品在贮运流通过程中发生冻融次数超过2次时明显降低产品食用品质和消费者接受度。

改进鱼类营养和饲料研究范式:从大口黑鲈和大黄鱼配合饲料在养殖生产中的应用谈起

鱼类营养和饲料研究起始于20世纪50年代,并借鉴对人类和畜、禽营养研究的经验建立了研究范式。在过去70年中,鱼类营养和饲料研究遵循已有的范式取得了大量的成果,这些研究成果推动了水产配合饲料技术的进步,为水产饲料产业从无到有、从小到大做出了贡献。然而,随着全球水产养殖规模的不断扩大,水产养殖产业面临的资源和环境压力日益增加,对水产饲料也提出了更多和更高的要求。养殖生产实践表明,根据一些肉食性鱼类营养和饲料研究结果设计配方生产的饲料不能取得预期的应用效果,这意味着遵循已有研究范式所得到的结果难以完全满足现代鱼类养殖生产的需要。本文总结了两种具有重要经济价值的肉食性鱼类(大口黑鲈和大黄鱼)配合饲料在养殖生产中应用的曲折历程,指出早期研究明显低估了饲料蛋白水平是导致配合饲料长期无法在养殖生产中成功应用的主要原因。早期研究报道大口黑鲈的饲料蛋白需求为400~440 g/kg,大黄鱼的饲料蛋白需求为450~470 g/kg,但投喂配合饲料的鱼的生长明显比投喂冰鲜鱼的鱼慢。重新评估发现大口黑鲈和大黄鱼饲料蛋白需求分别为480~510 g/kg和490~520 g/kg,投喂含适量蛋白的配合饲料时鱼生长与投喂冰鲜鱼时接近。对大口黑鲈和大黄鱼饲料蛋白需求的明显低估反映出已有鱼类营养和饲料研究范式中存在不足,其表现为:①强调食物对鱼类生长的影响,但忽视了鱼类遗传背景和食物外的其他环境条件对鱼类生长和摄食的作用;②强调鱼类个体生长可反映其营养需求和饲料质量,但忽视了鱼类个体生长并不能完全反映养殖产量和效益;③强调生长和饲料利用效率在评价水产养殖效益方面的重要性,但忽视了投饵养殖对自然资源和环境所产生的负面影响是限制水产养殖可持续发展的瓶颈;④基础饲料配方对评价营养需求或饲料质量的影响没有得到足够重视,因基础饲料组成不合理导致一些研究结果缺乏实际意义。针对上述问题,作者建议对已有范式的概念、理论和研究方法做如下改进:①重视鱼类遗传背景和食物以外的其它环境条件对鱼类生长的影响,明确鱼类生长潜力决定营养需求,而食物营养是实现生长潜力的条件;②重视食物中各种营养素之间的相互作用,明确不同饲料原料在配方的营养平衡中发挥不同的作用;③进行饲养实验时重视实验鱼种质和种群结构,重视对照组和处理组个体生长的差异幅度在判断处理效应方面的指示意义,重视饲料配方对自然资源和环境等制约水产养殖可持续发展的因素的影响。改进后的研究范式更符合现代水产养殖生产实际,遵循其开展研究获得的结果能够更好地指导饲料配方设计,所生产的配合饲料也能更好地应用于水产养殖生产。

白血病染色体MLL基因断裂(易位)FISH探针的研究

目的自主研制可以检测白血病染色体MLL基因断裂的双色FISH检测试剂盒。方法根据染色体基因图谱,选定合适的BAC克隆重叠群分别作为MLL基因断裂点5'端探针和3'端探针。采用缺口平移法,制作出5'端标记绿色荧光素,3'端标记红色荧光素的探针。用双盲法检测白血病临床样本40例,对自制探针和同类进口探针在各项技术参数上进行对比研究。结果自制探针检测MLL基因断裂(易位)的阴、阳性率与同类进口产品完全相符;在Spectrum Green和Cy3?v1通道中,自制探针的平均荧光信号强度比进口探针明显提高(自制探针分别为:2930.5±38.00,2766±59.54;进口探针分别为:2239±45.13,1986±59.56;P<0.01),自制探针信噪比分别为进口探针的2.4倍和1.9倍。结论自制的MLL基因FISH检测探针设计合理、质量可靠,与进口探针相比,荧光信号更强,信噪比更高,将来可能替代价格昂贵的进口产品。

棉籽蛋白替代鱼粉对斑点叉尾鮰生长性能、饲料利用和肠道组织结构的影响

试验旨在研究棉籽蛋白替代鱼粉对斑点叉尾鮰生长性能、饲料利用率和肠道组织结构的影响。设计鱼粉含量为100 g/kg的基础饲料,用棉籽蛋白分别替代基础饲料中0、20%、40%、60%、80%和100%的鱼粉配制成6组等蛋白饲料(D1、D2、D3、D4、D5组和D6组),饲养初始平均体重为(171±1)g的斑点叉尾鮰67 d。结果表明:与D1组相比,D5组和D6组的末均重和增重率显著降低,饲料系数显著增加(P<0.05);D3组、D5组和D6组的肝体比显著低于D1组(P<0.05);D6组肌肉粗蛋白含量显著高于D1组(P<0.05);各组斑点叉尾鮰存活率、肥满度、脏体比和肌肉的水分、粗脂肪和粗灰分含量均无显著差异(P>0.05);当棉籽蛋白100%替代鱼粉比例时,饲料的干物质表观消化率和蛋白质表观消化率显著下降(P<0.05),各组之间的脂肪表观消化率无显著差异(P>0.05);在肠道组织学中,棉籽蛋白替代鱼粉对肠道的绒毛高度和肌层厚度无显著差异(P>0.05)。综上所述,在鱼粉含量为100 g/kg的基础饲料中,棉籽蛋白可以有效替代60%的鱼粉不会影响斑点叉尾鮰的生长性能、饲料利用和肠道组织结构。

γ-聚谷氨酸和鱼蛋白水溶肥对松花菜生长和产量的影响

为明确γ-聚谷氨酸和鱼蛋白水溶肥在蔬菜生产上的作用,以松花菜为供试作物,设置常规施肥、γ-聚谷氨酸、鱼蛋白3个处理。试验结果表明,γ-聚谷氨酸处理和鱼蛋白处理都能显著提高松花菜的株高、茎粗,提升松花菜品质和产量,增加松花菜的经济效益,以鱼蛋白处理对松花菜增产增效效果更好。