影响草鱼出血病疫苗免疫效果因素风险评估

Risk assessment of factors affecting immune efficacy of grass carp hemorrhage disease vaccine

应用模糊层次分析法,并结合流行病学调查、荟萃分析和德尔菲法,构建了由评估指标体系、风险因素权重、评分标准、综合评价函数等组成的草鱼出血病免疫预防风险评估模型,其中,评估指标体系包括疫苗品质(B1)、免疫程序(B2)、鱼体(B3)、池塘环境(B4)和饲养管理(B5)共5个准则层风险因素和疫苗品种(C1)、保存温度与有效期(C2)、运输存储条件(C3)、免疫时疫苗的存放(C4)、免疫时鱼体健康状态(C5)、免疫技术(C6)、免疫剂量(C7)、漏免的鱼数(C8)、鱼种来源(C9)、健康状态(C10)、鱼体规格(C11)、水温(C12)、溶氧(C13)、氨氮(C14)、亚硝酸盐(C15)、pH值(C16)、透明度(C17)、水色(C18)、底泥厚度(C19)、载鱼量(C20)、搭配模式(C21)、药物的使用(C22)、饲料(C23)、青草投喂(C24)等24个指标层风险因素;5个准则层风险因素权重值集合为W={0.267;0.102;0.131;0.263;0.237},24个指标层风险因素绝对权重集合为W={0.138;0.059;0.046;0.024;0.035;0.018;0.027;0.022;0.040;0.054;0.037;0.076;0.037;0.032;0.030;0.027;0.018;0.019;0.024;0.104;0.024;0.027;0.062;0.020};分别建立了定性和定量评估指标的评分标准,并以综合评价函数1i疫池塘发病风险,结果显示,3个发病池塘风险值分别为0.572、0.638、0.617,处于高度风险级别,与未发病塘存在极显著差异(P<0.01),评估结果较准确,表明该模型可应用于草鱼出血病免疫预防管理和决策。

Risk analysis has been used regularly in the management of aquatic animal health, resulting in increased success at preventing and controlling diseases. A number of factors affect the efficacy of a vaccine in aquaculture. Thus, it is important to identify these risk factors and estimate their weights. We developed a quantitative risk assessment model for the prevention for grass carp hemorrhage disease by analyzing epidemiological study data using the Delphi method and meta-analysis. The model was composed of a risk hierarchy system, weight and valuation standards for each risk factor, and an integrated evaluation function. The risk hierarchy system included 5 criterion layers and 24 in-dex layers. The criterion layers included vaccine quality （B1）, immune program （B2）, fish （B3）, pond environment （B4）, and care and management （B5） with a set of weight about W={0.267, 0.102, 0.131, 0.263, 0.237}. The index layer con-sisted of vaccine species（C1）, storage temperature and expiration date（C2）, storage and transportation conditions （C3）, storage of the vaccine （C4）, health status of the fry following vaccination（C5）, vaccination technique（C6）, vaccination dosage（C7）, number of unimmunized fry （C8）, source of fry （C9）, health status of fish（C10）, size of fish（C11）, water temperature（C12）, dissolved oxygen（C13）, ammonia nitrogen（C14）, nitrite（C15）, pH （C16）, water transparency（C17）, water color（C18）, thickness of mud（C19）, rearing density（C20）, culture type（C21）, drug use（C22）, feed（C23）, and grass feed（C24） with a set of absolute weights about W={0.138, 0.059, 0.046, 0.024, 0.035, 0.018, 0.027, 0.022, 0.040, 0.054, 0.037, 0.076, 0.037, 0.032, 0.030, 0.027, 0.018, 0.019, 0.024, 0.104, 0.024, 0.027, 0.062, 0.020}. The results of the risk assessment were represented by the integrated evaluation function GI=∑i=1^m Ci·Pi . Using vaccination data from south-CP ii i=1 west China to validate the model, the integrated evaluation value from three infected ponds was 0.572, 0.638, and 0.617. These values were significantly higher than values from non-infected ponds （P〈0.01）.The results of the risk assessment are consistent with the survey data. Thus, our model can be used to reduce the risk of grass carp hemorrhagic disease by allowing culturists to plan with more certainty for increased immune efficacy.