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991.
992.
褐菖鲉生长缓慢,在浙江南麂海域2001年4月30日放养0.9g的苗种,至2001年6月7日达8.3g,当年底达24.8g,2003年6月26日达112.3g。总养殖成活率20.1%,平均日增重0.14g,平均增重率0.62%。秋末至夏初低水温期是其主要生长期。冬春季养殖成活率高于秋夏季,第一年夏季养殖成活率低,仅28.1%。饵料系数为3.6,食性为杂食性,对网箱具有明显的清洁作用。在9~13%低水温期亦会摄食与生长。适温下限在7.2℃以下,适温上限在25.6℃以下。养殖方式以混养为宜,生产安排以10月份收购502左右的苗种养至翌年6月达100g以上规格出售为好,该养殖模式能避开台风期与高温期。褐鲉鲇肉质细嫩,味道鲜美,近年颇受人们欢迎,其经济价值高,且我国沿海褐菖鲇苗种资源丰富,养殖开发前景良好。 相似文献
993.
Shiang‐Lin Huang Haiping Wu Xianyan Wang Chongwei Peng Chun‐Chieh Wang 《水产资源保护:海洋与淡水生态系统》2020,30(9):1775-1782
- Protecting critical habitats of the Indo‐Pacific humpback dolphin, Sousa chinensis, is a hot topic of discussion for marine biodiversity conservation in China and many Southeast Asian countries. In practice, sound habitat protection action (HPA) planning often suffers from information gaps in macroscopic habitat configurations and changes in the habitat conditions of humpback dolphins.
- Recent publications in the journal Aquatic Conservation: Marine and Freshwater Ecosystems (AQC) have served to advance humpback dolphin conservation in Chinese waters by resolving such habitat configurations and indicating significant changes in distribution patterns and habitat characteristics under intense coastal anthropogenic activity.
- We highlight an integrative research framework to investigate habitat configuration and long‐term habitat changes when planning a holistic HPA programme for humpback dolphins. When constructing habitat configuration baselines, field surveys should be designed and conducted in a systematic manner to ensure survey efforts cover diverse environments equally, in either a spatially stratified or gridded pattern, to minimize potential spatial sampling biases. Long‐term habitat changes can be revealed by comparing satellite images from different decades. Changes in habitat preferences and habitat characteristics can be explored through questionnaire surveys on local ecological knowledge, associating historical occurrences with coastline features and projecting historical habitat configuration by species distribution modelling exercises.
- A lack of good communication and sharing of information between research and management sectors can still be an obstacle to the implementation of sound conservation practices, however, even though there is robust scientific evidence to fill knowledge gaps in distribution and habitat baselines. We have addressed the need to establish a mechanism to improve and streamline information sharing between research teams, management sectors, and stakeholder groups.
994.
Xugan Wu Yongxu Cheng Liying Sui Xiaozhen Yang Tianzuo Nan & Jinqing Wang 《Aquaculture Research》2007,38(14):1459-1467
The morphological characteristics, tissue indices, proximate and fatty acid compositions of hepatopancreas, gonad and muscle of pond‐reared (PR) and lake‐stocked (LS) Eriocheir sinensis broodstock were compared. Lake‐stocked crabs are characterized by a blue carapace, white abdomen, golden legs and yellow setae while PR crabs have a brown carapace, grey abdomen, black legs and similar yellow setae. The carapace length and width of PR crabs were significantly less than those of LS crabs of the same wet weight (WW). The results showed that the hepatosomatic index (HSI) of PR males was significantly higher, but the gonadosomatic index (GSI) was significantly lower for PR females when compared with LS individuals of the same sex. Regardless of their origin, the muscular index (MI) of males was higher than that of females. The hepatopancreas of LS crabs had higher protein levels and lower lipid levels compared with PR crabs. The results of proximate analysis of male gonads from two different sources were similar, while the protein level in the ovary of LS females was higher than that of PR females. The tissues of males had higher water content but lower lipid and protein levels compared with females regardless of their source. The LS crabs had higher highly unsaturated fatty acid (HUFA) levels than PR crabs in their gonad and hepatopancreas. In conclusion, our results suggest that the nutritional quality of LS crabs is better than that of PR crabs, the nutritional quality of males is poorer than that of females. The reproductive performance and larval quality of crabs from these two rearing systems should be further verified. 相似文献
995.
Molecular characterization was carried out on an iridovirus isolated from yellow grouper, Epinephelus awoara . The major capsid protein (MCP) gene was located, sequenced and compared with homologous genes from other iridoviruses. The nucleotide sequence is 1392 bases long and contains a single open reading frame beginning at an ATG codon from the 5' end and terminating at a TAA codon at the 3' end. The open reading frame encodes a protein of 463 amino acids with a predicted molecular weight of 50 272 Da. Pairwise amino acid alignments detected a high degree of sequence identity between grouper iridovirus (GIV) MCP and the homologous genes of other iridoviruses. The MCP gene of GIV was most similar to the MCP gene from frog virus 3 (FV3) with 70% nucleotide and 73% amino acid sequence identity. The predicted molecular weight of the protein of this gene is comparable with the apparent weight obtained by SDS–PAGE. Pathogenicity of the GIV was investigated in yellow grouper by intraperitoneal injection of 107 and 104 TCID50 virus. Cumulative mortalities reached 100% within 11 and 25 days post-infection, respectively, while no grouper died in the control group. The molecular studies demonstrated that GIV is a member of the genus Ranavirus . 相似文献
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998.
选择福安水牛品种资源保护区临床健康的福安水牛公、母牛各10头进行福安水牛生理生化指标的测定。结果表明:福安水牛的呼吸频率、心率、体温都比滨湖水牛的都低;福安水牛的白细胞计数、血红蛋白比滨湖水牛略高,但在《奶牛疾病学》和《家畜生理学》的正常值范围内;福安水牛母水牛的红细胞数平均值比滨湖、摩拉、尼里、三元杂种、广西本地五种母水牛都低;福安水牛白细胞总数比湖南滨湖母水牛、摩拉水牛高,比尼里母水牛、广西灵山当地母水牛低;而福安母水牛的白细胞总数仅比广西灵山当地水牛低。福安水牛的生理生化指标在性别上没有显著性差异。 相似文献
999.
为分离和筛选产抗金黄色葡萄球菌乳酸菌素的优势乳酸菌,利用乳酸菌分离培养基MRS从收集的各种腌制菜汁中分离培养乳酸菌,通过细菌培养特性、革兰氏染色特点、生理生化特性初步鉴定,同时根据Genbank中乳酸菌的16SrDNA序列设计特异性引物,采用PCR方法进一步鉴定,并以金黄色葡萄球菌为指示菌对乳酸菌的发酵上清液进行抑菌特性研究。结果表明,从腌渍菜汁中分离获得90株产酸菌,通过形态学、生理生化特性和PCR鉴定,结果73株产酸菌为乳酸杆菌;分泌产物抑菌试验表明,有10株菌具有抑制金黄色葡萄球菌活性,经酸排除和过氧化氢排除试验,仍然有5株乳酸菌的分泌产物具有抑制金黄色葡萄球菌活性。可见,从腌渍菜汁分离到的乳酸菌具有抑制金黄色葡萄球菌活性的特性,主要是通过分泌乳酸菌素来发挥作用。 相似文献
1000.
犬附红细胞体病是由犬附红细胞体引起的一种以黄疸和贫血为主要特征的人畜共患传染病.该病流行范围广泛,对犬只危害严重.本文主要阐述了1例犬附红细胞体病的诊断过程,并提出一些相关的防治措施,以期为宠物临床上相关病例的诊治提供借鉴. 相似文献