新品种高寒鲤的选育

从１９７９年开始，用了约１５年时间，采用杂交和雌核发育上结合的方法，成本地将黑龙江野鲤的耐低温，荷包红鲤耐高密度养殖和镜鲤生长快等优良性状综合到三杂交种中，建立了Ⅰ，Ⅱ两个选育系，再用它们与野鲤和镜鲤回交，从６个回交种中选出２个与Ⅰ，Ⅱ两个雌核发育系组合成合成系并系统选育到Ｆ７，育成抗寒力达９７．６％，生长速度比当地养殖鲤快近一倍的高寒鲤。     

氨电极在鳙鱼和鲢鱼鲜度质量评定上的应用

本研究选用Orion95-12型氨电极对在-3℃、0℃和5℃保藏过程中的鳙鱼和鲢鱼鲜度质鼙进行测定，同时与康维(Conway)法测定结果进行比较，考察这两种方法测定结果的相互关系。研究中也将上述两种理化测定方法与细菌学测定方法进行对比，进一步验证其相互关系。研究结果表明各批样品用氨电极法测定的粗氨氮值与Conway’s法测定的挥发性盐基氮值相关系数在0.9521～0.9895之间，相关极显著；而理化指标与细菌学指标的相关系数在0.8143～0.9178之间，相关也显著。氨电极法具有测定结果可靠、设备规模小、价格便宜、操作简便和测定速度快等优点。推荐此法作为生产现场或研究机构对鱼类鲜度质量进行控制的检测方法。     

The in vitro effect of CpG-ODNs on the innate immune response of common carp, Cyprinus carpio L.

Unmethylated CpG dinucleotides within bacterial DNA or synthetic oligodeoxynucleotides (ODNs) can activate immune cells. A panel of synthetic oligodeoxynucleotides was evaluated in vitro for their ability to enhance the innate immune response of common carp (Cyprinus carpio L.). In vitro addition of CpG-ODNs enhanced the phagocytic activity and superoxide anion production of stimulated kidney phagocytes. The CpG-ODNs also induced lymphocyte proliferation in the fish kidney cells. The ODNs containing multiple CpGs generally resulted in greater stimulatory capacity, although CpGs located at the terminus of an ODN were ineffective. These results indicated that CpG-ODNs enhance the innate immune response of common carp.     

鲤鱼体组织中喹乙醇的残留规律研究

[目的]探索喹乙醇在鲤鱼体内的残留规律。[方法]采用高效液相色谱法(HPLC法)测定幼鲤鱼和成鲤鱼肝脏和肌肉中喹乙醇的残留量。[结果]鲤鱼肝脏中喹乙醇的残留量明显高于肌肉,而幼鲤鱼组织中喹乙醇的残留量要高于成鲤。饵料中菜籽粕不同用量对鲤鱼喹乙醇的残留量无显著影响(P0.05)。[结论]在实际生产中应禁止喹乙醇的使用。     

γ-Fe_2O_3纳米颗粒对鲤鱼各组织中SOD和GSH-Px酶活性的影响

为了研究γ-Fe2O3纳米颗粒对鲤鱼各个组织(脑,鳃,肝,肾,脾)的SOD和GSH-Px酶活性的影响,将大小一致的鲤鱼随机分为5组,分别暴露在0.1、1、10、100mg·L-1的γ-Fe2O3纳米颗粒悬浊液中,同时设有空白对照组,暴露30d后,测定各个组织匀浆中超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)的含量,从而评价γ-Fe2O3纳米颗粒对鲤鱼各组织的氧化损伤作用。结果表明,在实验浓度下(0～100mg·L-1),各组织对纳米颗粒的相对敏感性不同,与对照组相比,鳃、肝和脾组织中的SOD活力降低;而脑、肝和肾组织的GSH-Px含量降低,该结果表明γ-Fe2O3纳米颗粒对鲤鱼内脏组织的抗氧化系统有一定程度的损害。同时,肝组织中SOD和GSH-Px含量变化与γ-Fe2O3纳米颗粒染毒浓度存在一定的剂量——效应关系。上述结果说明肝脏为γ-Fe2O3纳米颗粒对鲤鱼氧化损伤中的靶器官。     

Nutritional studies on rats and fish (carp Cyprinus carpio) fed diets containing unheated and heated Jatropha curcas meal of a non-toxic provenance

Unheated and heated (121 ^°C, 66% moisture; 15, 30 and 45 min) Jatropha meals of non-toxic provenance from Veracruz state in Mexico were evaluated using rats and fish. With rats, the weight gain was highest for the casein diet followed by heated (30 min; only this treatment was studied using rats) and unheated Jatropha meal containing diets. The protein efficiency ratio (PER) for unheated and heated Jatropha meal containing diets was 37 and 86%, respectively, of the casein diet. On the other hand, the body weight gain, PER and feed conversion ratio of fish were statistically similar for unheated and heated (15, 30 and 45 min) Jatropha meal containing diets fed for a period of 35 days. Although these parameters were statistically similar for the unheated and heated Jatropha meal containing diets, the body weight gain, PER and protein productive value were highest and the feed conversion ratio lowest with 15 min heated Jatropha meal, suggesting that the heat treatment for 15 min is optimal for the meal. Trypsin inhibitor and lectin activities decreased drastically (>83 and 99%, respectively) after 30 and 45 min of heat treatment and after 15 min, the residual lectin activity was negligible and the residual trypsin inhibitor activity was 34%. These results, together with the nutritional parameters investigated, imply that Jatropha trypsin inhibitors and lectins do not have any adverse effects on carp at least up to 35 days of feeding. The nutritional value of Jatropha meal of the non-toxic provenance is high, and potential exists for its incorporation into the diets of monogastrics, fish and possibly humans.     

Variation in spawning responses, egg and larvae productions from induced rohu (Labeo rohita) during pre-monsoon and monsoon seasons: Relationship with hormonal changes and oocyte responsiveness during final maturation

Early induced spawning in captive rohu (Labeo rohita) often encounters with reduced spawning performances and devaluation of final product. The present study attempted to gain insight into the problems associated with poor performance of rohu during pre-monsoon spawning. A combination of sGnRHa and domperidone was used to induce final oocyte maturation (FOM) and ovulation in rohu during early (pre-monsoon, PM) and normal (monsoon, MN) spawning. The spawning performance parameters such as, spawning response, production and quality of egg and larvae showed significantly lower values (p < 0.05) in PM, when compared with MN spawning. The egg and spawn productions were recorded as 2.6 ± 0.05 and 2.41 ± 0.05 during the MN season, which were reduced by almost 50% in the PM season. Moreover the quality of egg and hatchling was devaluated significantly (p < 0.05) and exhibited higher percentage of mortality and abnormality in PM than those recorded in the MN season. The plasma concentration of carp gonadotropin (cGtH), 17β-estradiol (E) and 17α20β-dihydroxy-4-pregnen-3-one (DP) in relation to progress of FOM and ovulation at different seasons exhibited marked variation in hormonal profiles particularly in E and DP of PM fish. Higher initial plasma E (3.8 ± 0.3) and a distinct E peak clearly indicated the lack of transition from vitellogenic to post-vitellogenic stages that prevailed in PM rohu. Delayed DP and cGtH surge during FOM and ovulation resulted in longer latency period in spite of higher water temperature (31.5 °C) that prevailed during the PM period. In-vitro study on oocyte maturational competence (OMC) clearly depicted the lack of maturational competence in ovarian follicles during PM than MN in rohu. However priming the fish with purified carp gonadotropin (PCG) enhanced the acquisition of OMC in PM rohu in such an extent, that no marked seasonal differences (p > 0.05) in OMC were remained further, when compared with MN follicles. The PCG mediated acquisition of maturational competence was found to be dependent fully on new mRNA and protein synthesis in PM fish. The present study clearly demonstrated that the oocytes' unresponsiveness to hormonal induction was mainly responsible for reduced spawning performance in PM rohu, which could be ameliorated through PCG priming to achieve better spawning response in rohu during the pre-monsoon period. Thereby, the rohu fry production could be initiated successfully as early as May, allowing public and private hatcheries to produce larger age-0 rohu fingerlings ensuring reliable steady source of stocking materials for grow-out system earlier in the season.     

低pH水平对鱼类生理生化效应的影响研究

本文研究了低pH水平对鱼类血液电解质，血糖浓度和鳃组织酶活力影响。实验结果表明：低pH水平对鲤鱼血液K^ 的含量明显高于正常水平，Na^ 含量明显低于正常值，低pH为4．5－5．0时，鲤鱼血糖明显升高，体重下降，抑制生长，pH值为6．0时，21天起Na^ -K^ -ATPase酶活力明显下降，并有显著抑制作用（P＜0．05），历经30天有极显著抑制作用（P＜0．01）；pH值6．0加铝时，21天有极显著抑制（P＜0．01），抑制作用达到75％，pH5.5-5.0加铝时14天有极显著抑制（P＜0．01），抑制作用达到100％，pH4.5-4.0加铝时7天同样有极显著抑制（P＜0．01），抑制作用达到100％。     

文庆鲤酶解蛋白(EAP)的制备

以广东肇庆地区特产鱼种———文庆鲤为原料,通过筛选,选择枯草杆菌中性蛋白酶为实验用酶来制备文庆鲤酶解蛋白(EAP),并最终确定了最佳工艺条件:温度40℃,酶量2%,底物浓度1∶2,时间5.5 h。     

鲤鱼源粪肠球菌的体外抑菌试验研究

为证明益生菌候选菌株具有益生特性,将筛选的鲤鱼源粪肠球菌YL-1进行体外抑菌试验。结果发现,YL-1对病原菌嗜水气单胞菌有较强的抑菌作用;通过对YL-1上清液进行热处理,蛋白酶处理,中和酸等方式分析发现,其抑菌物质主要是对有机酸和胰蛋白酶敏感的一类物质。