去除内脏对冰藏鲤感官、化学和微生物变化的影响

以感官、TVBN、菌落总数、假单胞菌为指标,探讨去除内脏对冰藏鲤(Cyprinus carpio)品质变化及货架期的影响。结果表明,去除内脏和未去除内脏冰藏鲤的高品质期分别为333h和330h,货架期分别为575h和654h;去除内脏鲤冰藏的货架期略短,但无显著性差异(P0.05)。在冰藏过程中二者假单胞菌数量占优势,高品质期终点,去除内脏和未去除内脏鲤的菌落总数(CFU/g)的对数值分别为6.33±0.02和6.07±0.03;假单胞菌数(CFU/g)的对数值分别为6.15±0.19和6.04±0.01;挥发性盐基氮值分别为(10.86±0.50)mg/(100g)和(10.15±0.01)mg/(100g)。货架期终点,二者细菌总数(CFU/g)的对数值分别为7.06±0.18和6.90±0.14;假单胞菌数(CFU/g)分别为6.89±0.13和6.31±0.05;挥发性盐基氮值分别为(19.03±0.90)mg/(100g)、(21.15±0.80)mg/(100g)。二者在高品质期终点和货架期终点的各指标均无显著性差异(P0.05)。与未去除内脏鲤相比,冰藏初期去除内脏鲤的挥发性盐基氮值略低,而其细菌增殖较快且直接进入对数增长期,这可能是由于去除内脏过程对鱼体造成破坏所致,而过了高品质期后,无论是挥发性盐基氮值还是感官评分都比未去除内脏的高,因此去除内脏鲤的货架期略短。     

维生素E缺乏对鲤骨骼肌损伤的影响

本文旨在探讨VE缺乏对鲤骨骼肌损伤的形态学影响。在半纯合日粮中分别添加0、25、50和100 mg/kg的VE,投喂体重约60 g的鲤鱼20周。结果表明:鲤鱼摄入VE缺乏的饲料后,出现“瘦背症”、脊柱弯曲及以突眼、竖鳞和腹水为特征的渗出性素质样病变。病理剖解见体壁肌肉萎缩,特别是背部两侧肌肉萎缩变薄,其厚度仅为对照组的1/4~1/2,似刀刃状;体侧红肌纤维褪色变白,呈白肌肉外观。组织学变化主要表现为肌营养性不良,骨骼肌变性、坏死,淋巴细胞和单核细胞浸润,大量结缔组织增生,残存的肌纤维萎缩变细。超微结构上表现为骨骼肌细胞核膜间隙增宽,呈锯齿状,并发生局部或广泛性的断裂,核变形,电子密度降低;肌浆内糖原颗粒明显减少,线粒体肿胀,嵴断裂,甚至溶解呈空囊泡状,肌原纤维的横纹模糊不清或完全消失。结论:日粮中0、25和50 mg/kgVE水平会导致鲤出现VE缺乏症,其骨骼肌主要表现为变性、坏死、肌萎缩和炎症细胞浸润的肌营养性不良。     

含紫花苜蓿饵料对鲤鱼生长性能、肉品质及消化酶活性的影响

通过在日粮中添加不同水平的紫花苜蓿草粉和鲜草,研究苜蓿草粉及鲜草对禾花鲤生长性能、鱼肉品质、消化酶活性及经济效益的影响。选取整齐一致的2龄禾花鲤1440尾,随机分为6个处理,每处理3个重复,每重复80尾,分置于18个试验池中饲养。各处理饲粮中苜蓿草粉的添加量分别为0,4%,8%,12%,16%和0 鲜草,正试期50 d。研究结果显示:1)添加苜蓿草粉后,试验Ⅱ组的尾均日增重和增重率显著高于对照组。试验Ⅰ、Ⅲ组的上述2项指标高于对照组,试验Ⅳ组低于对照组,苜蓿鲜草组低于对照组,但差异均不显著。2)和对照组相比,添加苜蓿草粉显著(试验Ⅳ组)或极显著(试验Ⅰ、Ⅱ、Ⅲ组)提高了禾花鲤肌肉中粗蛋白质含量,随着苜蓿草粉添加水平的增加,肌肉中粗脂肪和胆固醇水平显著下降,肌肉中水分含量呈先降后升的二次变化趋势,苜蓿鲜草组的肌肉中粗蛋白质、粗脂肪含量和胆固醇水平无显著变化。3)添加苜蓿草粉后对消化道各部位蛋白酶活性及淀粉酶活性有促进作用,均呈先升后降的变化趋势,其中试验II组的酶活性最高。添加苜蓿鲜草对消化道各部位酶活性无显著影响。4)与对照组相比,试验Ⅰ、Ⅱ、Ⅲ组经济效益均有所提高,但以试验Ⅱ组最好。以上结果表明,在鲤鱼饲粮中添加8%紫花苜蓿草粉对鲤鱼生产性能、鱼肉品质及消化酶活性指标有较显著的改善,但紫花苜蓿鲜草不适宜直接投喂鲤鱼。结合生产实际,建议在鲤鱼饲粮中添加8%紫花苜蓿草粉。     

Effects of Dietary Quercetin on Growth Performance,Digestive Enzyme Activities,Immune and Antioxidant Functions of Cyprinus carpio北大核心CSCD

This experiment was conducted to investigate the effects of different dietary levels of quercetin on growth performance, digestive enzyme activities, immune and antioxidant functions of juvenile Cyprinus carpio. Three hundred juvenile Cyprinus carpio with an initial body weight of (26.00±0.50) g were randomly divided into 5 groups with 3 replicates per group and 20 fish per replicate. The control group (T1 group) was fed a basal diet, and the experimental groups were fed the basal diets supplemented with 50 (T2 group), 100 (T3 group), 200 (T4 group) and 400 mg/ kg (T5 group) quercetin, respectively. The experiment lasted for 8 weeks. The results showed as follows: 1) compared with T1 group, the final body weight of juvenile Cypri⁃ nus carpio in T3 and T4 groups was significantly increased (P < 0. 05), the weight gain rate and specific growth rate in T3 group were significantly increased (P<0.05), and the feed coefficient in all experimental groups was significantly decreased (P<0.05), which in T3 group was the lowest. With the specific growth rate as the evaluation index, according to the cubic regression model analysis, the optimal supplemental level of quercetin in the diet for Cyprinus carpio was 124.02 mg/ kg. 2) The activities of intestinal protease, lipase and amylase in T3 group were significantly higher than those in the other groups (P<0.05). 3) Compared with T1 group, the serum acid phosphatase (ACP) activity and complement 3 (C3) content in T3 group were signifi⁃ cantly increased (P<0.05); the serum complement 4 (C4) content in T3 group was the highest, and signifi⁃ cantly higher than that in the other groups (P<0.05); the serum lysozyme (LZM) activity and immunoglobu⁃ lin M (IgM) content in T3 and T4 groups were significantly increased (P<0.05), and the serum LZM activity in T3 group was significantly higher than that in T4 group (P<0.05). 4) Compared with T1 group, the activi⁃ ties of liver superoxide dismutase (SOD) and catalase (CAT) in T3 group were significantly increased (P< 0.05); the liver glutathione peroxidase (GPX) activity in T3 group was the highest, and significantly higher than that in the other groups (P<0.05); the liver total antioxidant capacity (T⁃AOC) in T3 and T4 groups was significantly increased (P<0.05); the liver malondialdehyde (MDA) content in T2, T3 and T4 groups was significantly decreased (P<0.05). In conclusion, the optimal supplemental level of quercetin can improve the growth performance, digestive enzyme activities, immune and antioxidant functions of juvenile Cyprinus carpio, and the optimal supplemental level is 100 mg / kg. © 2023 Chinese Journal of Clinical Research. All rights reserved.     

Stimulation of gonadal and germ cell development in larval and juvenile carp (Cyprinus carpio L.) by homologous pituitary extract

The data presented show that in larval carp, gonadal size has increased distinctly after treatment with homologous pituitary extract (PE). Moreover, the precocious onset of primordial germ cell proliferation and of sex differentiation into male and female gonads was induced. Body weight of treated and control specimens did not differ significantly from each other throughout the experiment. Treatment of juvenile carp with homologous PE led also to an increase in gonadal size without concomitant increase in body weight. Induction of precocious spermatogenesis was observed too. GTH-levels in control and PE-treated carp were monitored by means of a homologous radioimmunoassay, showing that in PE-treated carp the GTH-level was distinctly elevated. The possible role of pituitary hormones in larval and juvenile gonadal development is discussed.     

亚甲基蓝在鲤体内消除规律研究

为探究常规用药条件下亚甲基蓝及其代谢物在水产动物体内的分布和消除规律,以鲤(Cyprinuscarpio)为研究对象,以质量浓度为15 mg/L的亚甲基蓝溶液浸泡试验鱼0.5 h后,将其饲养于水族箱中,采用高效液相色谱-质谱串联法检测亚甲基蓝及其代谢物在鲤各组织中的质量浓度,采用PK Solver药动学药效学数据处理软...     

西北酸菜直投式发酵剂菌株高密度培养的研究

[目的]制备出适合西北酸菜发酵的复合直投式发酵剂。[方法]前期筛选出3个菌株:产酸速率快的东方醋酸杆菌AC5,降解亚硝酸盐高的干酪乳杆菌L5,醇香味适中的东方伊萨酵母Y7。对这3种菌分别进行高密度培养研究,确定菌体增殖的最佳培养基及培养条件。[结果]确定增殖培养基的成分是马铃薯汁、番茄汁、葡萄糖、蛋白胨和磷酸盐。通过正交试验和培养条件优化得出,AC5的最佳培养基为马铃薯汁含量40 g/L、番茄汁含量80 g/L、葡萄糖含量20 g/L、胰蛋白胨含量10 g/L、磷酸盐含量10 g/L,在pH 5.5、30℃、150r/min下培养24 h活菌数达到3.42×108cfu/ml;L5的最佳培养基为马铃薯汁含量40 g/L、番茄汁含量60 g/L、葡萄糖含量5 g/L、胰蛋白胨含量15 g/L、磷酸盐含量10 g/L,在pH 6.5、30℃、120 r/min下培养24 h活菌数可达到1.93×109cfu/ml;Y7的最佳培养基为马铃薯汁含量60 g/L、番茄汁含量60 g/L、葡萄糖含量20 g/L、胰蛋白胨含量20 g/L、磷酸盐含量10 g/L,在pH 6.0、35℃、150 r/min下培养24h活菌数可达到2.74×108cfu/ml。[结论]该研究使单位体积的活菌数有很大提高,为制备西北酸菜直投式发酵剂提供了依据。     

饲粮中添加苜蓿草粉对黄河鲤鱼抗氧化性能及脂质代谢的影响

选取来源一致、体质健康、尾均重约248.70±1.31 g的黄河鲤鱼750尾,采用单因子完全随机设计,设5个处理,3个重复,分别在基础饲粮中添加0%(对照组)、5%(试验Ⅰ组)、10%(试验Ⅱ组)、15%(试验Ⅲ组)和20%(试验Ⅳ组)的苜蓿草粉,以探讨苜蓿草粉对黄河鲤鱼抗氧化性能及脂类代谢的影响.结果显示,1)添加5%和10%的苜蓿草粉能显著或极显著提高黄河鲤鱼血清和肝胰脏中超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活力,同时也能显著或极显著降低丙二醛(MDA)含量,说明苜蓿草粉能有效地提高黄河鲤鱼的抗氧化能力.2)血清、肝胰脏和肌肉中总胆固醇和甘油三酯含量都随着苜蓿草粉添加量的增加依次降低.其中,在血清中,试验Ⅳ组2指标含量均显著低于对照组(P<0.05),但另外3个试验组和对照组之间差异均不显著(P>0.05);在肝胰脏中,试验Ⅱ、Ⅲ、Ⅳ组的总胆固醇和试验Ⅳ组甘油三酯含量显著低于对照组(P<0.05);在肌肉中.试验Ⅲ、Ⅳ组的总胆固醇含量显著低于对照组(P<0.05).但苜蓿草粉的添加对血清中高密度脂蛋白和低密度脂蛋白含量并未形成显著性影响(P>0.05).