Biswas P K, Uddin G M N, Barua H, Roy K, Biswas D, Ahad A, Debnath N C
Department of Microbiology, Chittagong Veterinary and Animal Sciences University (former, Chittagong Government Veterinary College), Khulshi, Chittagong 4202, Bangladesh.
Prev Vet Med. 2008 Mar 17;83(3-4):260-71. doi: 10.1016/j.prevetmed.2007.08.001. Epub 2007 Sep 12.
We determined the flock sizes and rates of loss caused by different factors in broody-hen chicks (BHC) up to 60 days of age on 600 randomly selected smallholdings in Bangladesh. The smallholders were beneficiaries of a village poultry production chain called 'Smallholder Livestock Development Project-2' (SLDP-2) which was undertaken with the financial assistance of the Danish International Development Agency (DANIDA). For estimating survival time of BHC, we observed chicks in 80 smallholdings. SLDP-2 aims at ameliorating poverty among women by poultry rearing at village level; in total, 104,000 key rearers, constituting 96% of all of the beneficiaries of the SLDP-2 area, were enrolled in 26 upazilas (a lower administrative unit of Bangladesh). A key rearer is a smallholder who rears at least five 'Sonali' (RIR x Fayoumi) and some indigenous (desi) chickens in a semi-scavenging system. Sonali chickens are supplied from the development project, and have higher egg production while the broodiness of the desi hens is exploited to get chicks hatched for future stocks; thus, the chicks hatched and reared to 60 days old at key rearers' households are called BHC. In this study 32% of the smallholders had BHC each month. At the beginning of a month, the median number of chicks in a flock was 8, and the mean survival time was 50.5 days. Incidence rates of loss of BHC from disease, predation, selling and slaughtering were 0.102, 0.086, 0.009 and 0.002 per chick-month at risk, respectively. The major predators were crows, mongooses and eagles with incidence rates of loss being 0.018, 0.016 and 0.010 per chick-month at risk, respectively. Colibacillosis (both single and mixed infections) contributed to the death of 21% of dead BHC collected; Newcastle disease and salmonellosis contributed to the next highest (14 and 12%) proportional mortalities.
我们在孟加拉国随机选取了600个小农场，确定了60日龄内不同因素导致的抱窝母鸡所孵小鸡（BHC）的鸡群规模和损失率。这些小农场主是一个名为“小农户畜牧发展项目2”（SLDP - 2）的乡村家禽生产链的受益者，该项目是在丹麦国际开发署（DANIDA）的财政援助下开展的。为了估计BHC的存活时间，我们在80个小农场观察了小鸡。SLDP - 2旨在通过在村级饲养家禽来改善妇女贫困状况；在26个乡（孟加拉国的一个下级行政单位），共有104,000名核心饲养者登记参与项目，占SLDP - 2地区所有受益者的96%。核心饲养者是指在半放养系统中饲养至少5只“索纳利”（RIR×法尤米）鸡和一些本地（德西）鸡的小农场主。索纳利鸡由发展项目提供，产蛋量较高，而利用本地母鸡的抱窝性来孵化小鸡以供未来养殖；因此，在核心饲养者家庭中孵化并饲养到60日龄的小鸡被称为BHC。在本研究中，32%的小农场主每月都有BHC。在一个月开始时，一个鸡群中小鸡的中位数为8只，平均存活时间为50.5天。每只处于风险中的小鸡每月因疾病、捕食、出售和屠宰导致的BHC损失发生率分别为0.102、0.086、0.009和0.002。主要捕食者是乌鸦、獴和鹰，每只处于风险中的小鸡每月的损失发生率分别为0.018、0.016和0.010。大肠杆菌病（单一感染和混合感染）导致收集到的死亡BHC中有21%死亡；新城疫和沙门氏菌病导致的死亡率次之（分别为14%和12%）。
