怀山药皮对淇河鲫血清生化、免疫指标及组织结构的影响

为探究怀山药皮(Chinese yam peel,YP)对淇河鲫免疫的影响,选取平均体重为(106.76±3.74)g的淇河鲫240尾,随机分为对照组(NC)、0.5%怀山药皮添加组(LYP)、1%怀山药皮添加组(MYP)、2%怀山药皮添加组(HYP)4组,养殖8周,检测实验鱼生长指标、血清生化指标及免疫相关基因的表达情况。结果显示:添加怀山药皮对淇河鲫生长指标没有显著性影响;血液生化指标中谷草转氨酶活性在MYP组显著性降低,碱性磷酸酶的活性显著升高;与NC组相比,怀山药皮添加组肝脏细胞膜与核膜完整性增强,胞质破碎,核溶解、偏移现象减轻;与NC组相比,添加怀山药皮上调了抑炎因子(IL-10)、紧密连接蛋白基因(Claudin-1)、抗氧化基因(CAT和GST)和TLR通路基因(TLR4)mRNA表达量。以上结果表明,饲料中添加怀山药皮,能在一定程度上增强鱼体免疫力。     

流沙湾海域勒氏枝鳔石首鱼生物学性状的初步研究

在2013年1—12月渔业资源调查数据的基础上,研究了流沙湾海域勒氏枝鳔石首鱼的体长分布、体长-体质量的关系、肥满度月变化、饵料组成、摄食强度和营养级等生物学特性。结果表明:流沙湾海域枝鳔石首鱼体长82~145 mm,优势体长组为116~125 mm和106~115 mm;体长(L)-体质量(W)关系方程为:W=0.0242L~(2.9564)(R~2=0.9471);肥满度最大值出现在2月份,最小值出现在7月;枝鳔石首鱼的饵料组成以甲壳类为主要类群。枝鳔石首鱼的空胃率随季节变化显著(P0.05),在冬季最大,春季达到最小,饱满度指数在秋季最高,冬季最低;营养级变化范围在2.69~3.11,平均营养级为2.94。     

Effect of Bacillus cereus as a water or feed additive on the gut microbiota and immunological parameters of Nile tilapia

We evaluated the effects of Bacillus cereus, as an additive in water and feed, on the gut microbiota and immunological parameters of Nile tilapia (Oreochromis niloticus) fingerlings. Experiments were performed in tanks and net cages respectively. Experiment 1: Tilapia were housed in tanks for 42 days, and B. cereus was added to the water at 1.0 × 10⁴ cfu mL^?1 (Treatment 1) and 1.0 ×10⁵ cfu mL^?1 (Treatment 2) weekly. For the control, no probiotic was added. Experiment 2: Tilapia were housed in cages for 42 days, and the feed was supplemented with B. cereus at 1.0 × 10⁷ cfu g^?1 (Treatment 1) and 1.0 × 10⁸ cfu g^?1 (Treatment 2) weekly. For the control, no probiotic was added. Each treatment contained three replicates, with 50 male tilapias per replicate. The fish from the probiotic treatments in both tank and cage experiments had significantly higher serum lysozyme and peroxidase activities than the control. In the cage experiment, alkaline phosphatase and total superoxide dismutase activities in tilapia were significantly higher in probiotic treatments compared with the control. The results of polymerase chain reaction‐denaturing gradient gel electrophoresis showed that B. cereus supplementation in the feed and water affected the autochthonous gut bacteria community of tilapia and stimulated various potentially beneficial bacteria. Therefore, B. cereus, as a water or feed additive, could enhance the immune status and affect the gut microbiota of tilapia. Bacillus cereus was more effective as a feed supplement rather than a water additive for enhancing the immune status of tilapia.     

南美白对虾(Penaeus vannamei Boone)养殖污染的营养学(Nutriology)调控

南美白对虾养殖污染严重，本文从营养素的生态调整和绿色添加剂的应用两方面综合阐述了南美白对虾养殖污染的营养学调控途径。以期从源头上来控制和调节南美白对虾的营养代谢。减轻环境压力，实施可持续发展。     

Apparent digestibility coefficients of selected feed ingredients for juvenile snakehead,Ophiocephalus argus

Apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, gross energy, phosphorus and amino acids in Peruvian fish meal, poultry by‐product meal, meat and bone meal, spray‐dried blood meal, hydrolysed feather meal, corn gluten meal, soybean meal, peanut meal, cottonseed meal and rapeseed meal were determined for juvenile snakehead (Ophiocephalus argus) with initial mean body weight of 78.1 g. A reference diet and test diets that consisted of a 70 : 30 mixture of the reference diet to test ingredient were used with 5 g kg^?1 Cr₂O₃ as an external indicator. Fish meal, poultry by‐product meal and corn gluten meal had higher ADCs of dry matter, crude protein, and gross energy among ingredients tested. Dry matter ADCs ranged 61.9–81.5% for animal ingredients and corn gluten meal and ranged 52.2–68.0% for soybean meal, peanut meal, cottonseed meal and rapeseed meal. Energy ADCs of ingredients followed similar trends to differences in dry matter digestibility. Protein ADCs of animal and plant ingredients ranged 73.6–92.8% and 75.3–85.6%, respectively. Amino acid ADCs generally reflected protein digestibility. Lipid ADCs were relatively high for the ingredients tested. Phosphorus ADCs of animal and plant ingredients ranged 39.5–65.2% and 38.7–57.1%, respectively.     

Ontogenetic development of digestive enzymes and effect of starvation in miiuy croaker <Emphasis Type="Italic">Miichthys miiuy</Emphasis> larvae

The ontogenetic development of the digestive enzymes amylase, lipase, trypsin, and alkaline phosphatase and the effect of starvation in miiuy croaker Miichthys miiuy larvae were studied. The activities of these enzymes were detected prior to exogenous feeding, but their developmental patterns differed remarkably. Trypsin activity continuously increased from 2 days after hatching (dah), peaked on 20 dah, and decreased to 25 dah at weaning. Alkaline phosphatase activity oscillated at low levels within a small range after the first feeding on 3 dah. In contrast, amylase and lipase activities followed the general developmental pattern that has been characterized in fish larvae, with a succession of increases or decreases. Amylase, lipase, and trypsin activities generally started to increase or decrease at transitions from endogenous to exogenous feeding or diet changes, suggesting that these enzymatic activities can be modulated by feeding modes. The activities of all the enzymes remained stable from 25 dah onwards, coinciding with the formation of gastric glands and pyloric caecum. These results imply that specific activities of these enzymes underwent changes due to morphological and physiological modifications or diet shift during larval development but that they became stable after the development of the digestive organs and associated glands was fully completed and the organs/glands functioned. Trypsin and alkaline phosphatase were more sensitive to starvation than amylase and lipase because delayed feeding up to 2 days after mouth opening was able to adversely affect their activities. Enzyme activities did not significantly differ among feeding groups during endogenous feeding; however, all activities were remarkably reduced when delayed feeding was within 3 days after mouth opening. Initiation of larvae feeding should occur within 2 days after mouth opening so that good growth and survival can be obtained in the culture.     

不同饵料对中华虎头蟹幼体发育和存活率的影响

为探讨中华虎头蟹苗种繁育过程中饵料及投喂的影响,进行了不同饵料对中华虎头蟹溞状幼体和大眼幼体生长发育和存活的影响实验。实验结果,中华虎头蟹各期幼体生长发育效果较好的饵料为动物性饵料,Z1期以卤虫无节幼体为开口饵料,只投喂扁藻后期幼体发育较差;Z2以轮虫和卤虫无节幼体的搭配为好;Z3期则以轮虫为适宜饵料;M期投喂卤虫无节幼体效果相对较好。     

加州鲈迟缓爱德华氏菌病的检测和防治

以江苏省吴江市八坼镇区域养殖场加州鲈鱼病鱼的细菌性病原体为研究对象。通过分离纯化,形态学观察,结合16S rRNA基因序列同源性检索,对该病原菌进行初步判断。同时进行药敏实验,了解该病原菌对各种抗生素的耐药性和敏感程度。研究结果:分离纯化得到2株纯菌株L2F和L2P2,革兰染色均呈红色,阴性杆状菌。16S rDNA序列分析,L2F和L2P2菌株与迟缓爱德华氏菌(Edwardsiella tarda)的同源性达99%。初步判断该菌为迟缓爱德华氏菌。药敏实验结果,该菌对磺胺异恶唑、链霉素和利福平等药物不敏感或耐药,对左氧氟沙星、诺氟沙星、恩诺沙星、强力霉素、氟苯尼考、头孢哌酮相对敏感。     

Screening of cold-resistant seedlings of a Chinese wild grape (Vitis piasezkii Maxim var. pagnucii) native to loess plateau of eastern Gansu province,China, as rootstocks

Seedlings of a Chinese wild grape (Vitis piasezkii Maxim var. pagnucii) native to loess plateau of Eastern Gansu province, China, were evaluated to screen cold-resistant rootstocks in Lanzhou area. After 14-year investigation two selections of LDP-191and LDP-294 were screened as rootstocks for two table grape cultivars, ‘Fujiminori’ and ‘Red Globe’, respectively. The two graft unions demonstrated very high cold-resistance as well as good graft compatibility. Furthermore, they could survive through low temperatures in winter without soil coverage together with good fruit quality of the cultivars grafted.     

大蒜高产栽培技术及病虫害防治

大蒜为百合科葱属植物蒜的鳞茎。大蒜的幼苗、花茎、鳞茎均为广大群众所喜食,不仅可以生食和做成调味品,还可以做成糖醋蒜、罐头和大蒜油等产品出口创汇。大蒜栽培历史有2000多年,大蒜是人们日常生活不可缺少的辛香类蔬菜。大蒜含有丰富的糖类、蛋白质、脂肪、粗纤维,数量元素、维生素和大蒜素,营养与保健价值极高,被誉为“天然广谱杀菌素”。