棕点石斑鱼中草药免疫增强剂的快速筛选

采用离体外周血白细胞与中草药水提液共同孵育法,快速筛选棕点石斑鱼中草药免疫增强剂。39种生药量浓度为100 mg/ml 的中草药水提液及添加5.0 mg/ml 酵母聚糖的中草药水提液分别与棕点石斑鱼外周血白细胞孵育后,采用氮蓝四唑(NBT)还原法检测各种中草药水提液对棕点石斑鱼外周血白细胞氧呼吸爆发活性的影响,再以吞噬乳胶微球法检测具有显著增强白细胞氧呼吸爆发活性效果的中草药对棕点石斑鱼白细胞吞噬活性的影响,筛选中草药免疫增强剂,并将其拌料饲喂棕点石斑鱼,考察其对棕点石斑鱼外周血和头肾白细胞氧呼吸爆发活性的影响。结果显示,39种中草药中有10种对棕点石斑鱼离体白细胞氧呼吸爆发活性显著提高15%以上,3种酵母聚糖添加组对白细胞氧呼吸爆发活性提高70%以上;筛选出可同时提高棕点石斑鱼离体白细胞的氧呼吸爆发活性和吞噬活性的 3种中草药,它们分别为鸡血藤、黄柏和墨旱莲。拌料饲喂实验结果显示,饲喂1%的鸡血藤、黄柏和墨旱莲可显著提高棕点石斑鱼体内外周血和头肾白细胞氧呼吸爆发活性。     

Yeast extract, brewer’s yeast and spirulina in diets for Labeo rohita fingerlings affect haemato-immunological responses and survival following Aeromonas hydrophila challenge

A feeding trial was conducted for 60 days to study the immunomodulatory role of three different immunostimulants yeast extract (YE), brewer’s yeast (BY) and spirulina (SP) in Labeo rohita fingerlings. Four hundred and fifty fingerlings (avg. wt 3.35 ± 0.15 g) were randomly distributed in ten treatments and fed with either of ten iso-nitrogenous and iso-caloric semi-purified diets, prepared with three incremental levels (1%, 2% and 4%) of different immunostimulants except the control. Growth parameters did not vary significantly (p > 0.05) among the experimental groups. Haematology and serum parameters was performed before Aeromonas hydrophila challenge whereas respiratory burst activity was analysed following challenge. The respiratory burst activity, total leucocyte count, serum total protein and globulin was significantly higher (p < 0.05) in YE 1% supplemented group. The survival (%) after challenging with A. hydrophila was also highest in the YE fed groups. The results indicate that among the different sources and levels of immunostimulants, YE at lower inclusion level is more effective in promoting the immune status of L. rohita fingerlings.     

Immunomodulatory potential of marine secondary metabolites against bacterial diseases of shrimp

Shrimp disease management using bioactive marine secondary metabolites (MSMs) was developed as a package of practice for the sustainable shrimp farming. Therefore, the effect of MSMs on the host defense factors of shrimp was evaluated in the present study. Findings indicated that Ulva diet significantly increase the defense factors such as haemogram, agglutination index, phagocytic rate, bacterial clearance and serum bactericidal activity of treated shrimps over the control group. Based on the gut bacterial load, Ulva diet was considered as proactive drug whereas Dendrilla diet was determined as a curative agent.     

水产动物免疫增强剂的研究现状及应用前景

水产养殖业在世界范围内蓬勃发展的同时，由于高密度集约化养殖、过量投饵等原因，而造成环境恶化，导致各类细菌病、病毒病的频繁发生，严重阻碍了水产养殖业的持续健康发展。鱼类、贝类、虾类、蟹类均发生过大面积死亡，尤其某些病毒性疾病的死亡率可达60％-100％，对水产养殖业的打击是毁灭性的。目前已从生理、病理、种质、营养、生态、流行特点等方面进行了大量研究，以使用抗生素为代表的传统治疗方法，因其易导致养殖动物产生抗药性、易有残留等原因，在各国逐渐被禁用和取代。免疫机制的研究是合理有效防治各类病害的根本和依据，近来免疫学研究已成为水产动物病害研究的热点之一。     

Immunostimulant effect of a mixed herbal extract on infectious bursal disease virus (IBDV) vaccinated chickens in the context of a co-infection model of avian influenza virus H9N2 and IBDV

This study was conducted to assess the comparative effects of a mixed herbal extract (MHE) containing Ocimum sanctum, Withania somnifera, Emblica officinalis, Tinospora cordifolia, Mangifera indica, and Asphaltum (shilajit) on infectious bursal disease virus (IBDV)-vaccinated (VAC) chickens infected with IBDV and avian influenza virus (AIV) H9N2. The experiment included three groups (G1-G3): G1, the negative control group; G2, the VAC + challenged (Ch) group; and G3, the VAC + Ch + MHE group. MHE was orally administered continuously for 5 weeks post-vaccination (PV) with IBDV at 12 days of age, and the chicks were simultaneously challenged with virulent IBDV (intraocularly) and AIV H9N2 (intranasally) at 21 days PV. Blood and tissue samples as well as tracheal and cloacal swabs were gathered at different times PV and post-challenge. Immunological and haematological parameters, histopathological lesions, relative organ weights and final live weights revealed significant differences (P ≤ 0.05) between G2 and G3 groups. Furthermore, in the G3 group, the protection rates, ELISA and HI titers and CD4+/CD8+ ratio were significantly increased, whereas viral shedding titers and the heterophil/lymphocyte ratio were decreased. In conclusion, the oral administration of the mixed herbal extract for 5 weeks can stimulate the immune response to IBDV vaccination and relieves the pathogenicity of an AIV H9N2 and IBDV co-infection in chickens.