A number of studies have demonstrated the clear beneficial impact that vaccinating against Newcastle disease (ND) can have on reducing the frequency and severity of ND outbreaks. Here we go one step further and analyse the additional benefits in terms of improved production that result from vaccination. Data were collected from a cross sectional survey in Uganda of 593 chicken-rearing smallholders (for the purpose of this study this was defined as a farm with fewer than 75 chickens). Consenting participants were administered a detailed questionnaire covering a range of aspects of chicken production and management. These data were subsequently analysed in a generalised linear model framework with negative binomial error structure and the total offtake over the previous 12 months (chicken sales + chicken consumption + chickens gifted) was included as the dependent variable. Different measures of flock size were tested as independent variables and the model was also offered the district of the flock, ND vaccine adoption, use of poultry housing, provision of supplementary feed and use of dewormers as potential independent variables. We also developed an analogous model for the offtake of eggs (sale and consumption). The total size of the flock (counting chickens of all ages) was the measure of flock size that had the strongest association with offtake and was a significant but weak effect with an incidence rate ratio (IRR) of 1.011 (95 % Confidence intervals (CIs) = 1.007-1.015). ND vaccine adoption had a strong significant positive effect on offtake with an IRR of 1.571 (95 % CIs = 1.363-1.808). Use of a poultry house also had a significant effect (IRR = 1.365, 95 % CIs = 1.193-1.560). In the model of egg production, the number of hens was the demographic determinant with the lowest Akaike Information Criterion (AIC) (IRR = 1.094, 95 % CIs = 1.056-1.136) and ND vaccine adoption had a strong positive effect on egg offtake (IRR = 1.801, 95 % CIs = 1.343-2.412). Vaccinating against ND has a clear beneficial impact on the productivity of the flock, and the livelihoods of smallholder farmers.

中文翻译：

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新城疫疫苗接种和畜牧业做法对乌干达小农户鸡生产力的影响分析。

大量研究表明，接种新城疫（ND）疫苗可以明显减少ND暴发的频率和严重性。在这里，我们进一步走了一步，分析了疫苗接种带来的产量提高带来的其他好处。数据来自乌干达593家养鸡小农户的横断面调查（就本研究而言，这被定义为养鸡场少于75只的农场）。同意的参与者得到了一份详细的调查表，涵盖了鸡肉生产和管理的各个方面。随后在具有负二项式误差结构的广义线性模型框架中分析了这些数据，并将前12个月的总摄取量（鸡肉销售量+鸡肉消费量+有天赋的鸡肉）作为因变量。对鸡群大小的不同度量作为独立变量进行了测试，该模型还提供了鸡群区域，ND疫苗的采用，家禽舍的使用，补充饲料的供应和驱虫剂的使用作为潜在的独立变量。我们还开发了鸡蛋摄取（销售和消费）的类似模型。鸡群的总大小（计算所有年龄段的鸡）是与摄入量最强关联的鸡群大小的度量，并且是显着但微弱的影响，发生率（IRR）为1。011（95％置信区间（CIs）= 1.007-1.015）。采用ND疫苗对摄入量具有显着的显着正效应，IRR为1.571（95％CI = 1.363-1.808）。使用禽舍也有显着效果（IRR = 1.365，95％CI = 1.193-1.560）。在产蛋模型中，母鸡的数量是Akaike信息准则（AIC）最低的人口统计学决定因素（IRR = 1.094，95％CIs = 1.056-1.136），采用ND疫苗对鸡蛋的摄取有很强的积极影响（ IRR = 1.801，95％CI = 1.343-2.412）。接种抗ND疫苗对羊群的生产力和小农的生计有明显的有益影响。使用禽舍也有显着效果（IRR = 1.365，95％CI = 1.193-1.560）。在产蛋模型中，母鸡的数量是Akaike信息准则（AIC）最低的人口统计学决定因素（IRR = 1.094，95％CIs = 1.056-1.136），采用ND疫苗对鸡蛋的摄取有很强的积极影响（ IRR = 1.801，95％CI = 1.343-2.412）。接种抗ND疫苗对羊群的生产力和小农的生计有明显的有益影响。使用禽舍也有显着效果（IRR = 1.365，95％CI = 1.193-1.560）。在产蛋模型中，母鸡的数量是Akaike信息准则（AIC）最低的人口统计学决定因素（IRR = 1.094，95％CIs = 1.056-1.136），采用ND疫苗对鸡蛋的摄取有很强的积极影响（ IRR = 1.801，95％CI = 1.343-2.412）。接种抗ND疫苗对羊群的生产力和小农的生计有明显的有益影响。