Husbandry and trade of indigenous chickens in Myanmar—Results of a participatory rural appraisal in the Yangon and the Mandalay divisions

There is a variety of professions working with village chickens in developing countries, including farmers, veterinarians and chicken traders. People from all these occupations were involved in a participatory rural appraisal to investigate husbandry practices and trade of village chickens in Myanmar. Data were collected in two climatically different regions of the country, in the Yangon and in the Mandalay divisions. The breeding and training of fighting cocks was practised only in the Mandalay division, with well-trained birds sold for very high prices. Apart from this, chickens were raised in both regions mainly for small disposable income and were generally sold when money was needed, in particular during religious festivals. Chicken traders on bicycles, often called ‘middle men’, usually purchase birds from farmers in about 10 villages per day. Several ‘middle men’ supply birds to wealthier chicken merchants, who sell these birds at larger chicken markets. There is in general limited knowledge among farmers about the prevention of Newcastle disease via vaccination. Commercial indigenous chicken production is practised in Myanmar, but family poultry farming dominates indigenous chicken production in the country.     

山东省肉仔鸡新城疫流行病学调查

采用鸡胚接种法从山东省的潍坊、烟台、青岛、淄博、滨州、东营、聊城、济宁、临沂、日照、德州等地分离到32株有血凝性的病毒，经HA、HI试验及血清中和接种鸡胚试验，27株被确定为新城疫病毒，其中25株来自于发病鸡群．2株来自从发病鸡场中捕捉的麻雀。参照国际上规定的新城疫病毒毒力判定标准及其方法，测定27株新城疫病毒的鸡胚最小致死量平均死亡时间(MDT)为37．6～56．8h；1日龄雏鸡脑内接种致病指数(ICPI)为1．74～1．92；6周龄鸡静脉注射致病指数(IVPI)为2．11～2．70。测定结果表明：27株新城疫病毒为新城疫强毒。用27株分离的新城疫病毒接种14日龄新城疫非免疫鸡，其发病率为100％，病死率为70％～90％。调查统计发生鸡新城疫的肉仔鸡群的有关情况。调查结果表明：鸡新城疫在山东省的潍坊、烟台、青岛、淄博、滨州、东营、聊城、济宁、临沂、日照、德州等地存在不同程度的流行，且一年四季均可出现，其中冬天出现的频率最高(12／25)。多种日龄的鸡均可发生鸡新城疫，其主要的发病日龄为20～40日龄，10日龄以内的雏鸡亦可发病，死亡率有时超过70％。而且发病鸡的发病日龄越小，死亡率越高。     

Genetic Resistance of Egyptian Chickens to Infectious Bursal Disease and Newcastle Disease

Genetic resistance of native Egyptian breeds to very virulent infectious bursal disease virus (vvIBDV) and Newcastle disease virus (NDV) was investigated in two experiments. In the first experiment, birds from four breeds (Gimmizah, Sina, Dandrawi and Mandarah) were challenged with vvIBDV. The Mandarah chickens had the lowest mortalities (10%) compared to the Gimmizah, Sina and Dandrawi chickens (55%, 35%, and 55%, respectively). Antibody response, lymphocyte response to mitogen, and bursal lesions did not clearly correlate with the mortality rates. In the second experiment, the four chicken breeds were challenged with virulent NDV. The Mandarah chickens re-emerged as a resistant breed (20%, mortality), while the Sina, Dandrawi and Gimmizah breeds were highly susceptible (85%, 100% and 100% mortality, respectively). Further studies on the resistance mechanism are warranted.     

Comparison between a Live and an Inactivated Vaccine against Newcastle Disease in Village Chickens. A Field Study in Northern Malawi

A total of 156 chickens in two villages in Malawi were marked and sampled. One hundred and fifteen of these were vaccinated against Newcastle disease immediately after blood sampling, using the V4 heat-resistant strain applied by eye-drop in one village and the inactivated Newcavac vaccine in the other village. A second blood sample was collected 4 weeks after vaccination. The samples were examined using an indirect ELISA test kit. The titre group median ranged from 2 to 3 before vaccination. Both vaccines led to a positive immune response. Newcavac induced higher and more homogeneous titres compared with the V4 vaccine. There was also an increase in the median of the control group where V4 live vaccine had been applied. The differences between the median titres induced by V4, Newcavac and controls were statistically significant.     

Enhancement of mucosal immune responses by intranasal co-delivery of Newcastle disease vaccine plus CpG oligonucleotide in SPF chickens in vivo

Immunostimulatory CpG oligodeoxynucleotides (ODN) have been tested as immunoadjuvants for various vaccines in mice and human. Findings from previous reports suggest that CpG ODN can be used to enhance magnitude and balance of an immune response while reducing undesirable side effects of commercial vaccine, when delivered by parenteral route. Recently, it has been showed that CpG ODN is a promising mucosal adjuvant in mice, but data on mucosal immune responses induced by CpG ODN in other animals, especially in chickens, are scarce. Herein, we evaluated intranasal (IN) delivery of CpG ODN with newcastle disease (ND) vaccine (NDV) to determine its potential as a mucosal adjuvant to a commercial vaccine. CpG ODN augmented systemic (IgG in serum, T cell proliferation) and mucosal (IgA in intestinal washings and feces) immune responses against antigen. CpG ODN stimulated effectively both systemic and mucosal immune responses when delivered intranasally. Results from this study indicate that stimulatory CpG ODN is a potential effective mucosal adjuvant for the NDV in SPF chickens and may be applicable to husbandry animals.     

徐州地区新城疫流行病学调查与分析

对徐州地区三个禽病门诊2012年资料进行了初步统计,发现新城疫门诊量占15．1％,其中20日龄以内发病占51．6％,发病率和病死率也以20日龄以内居高。20日龄以内病鸡多表现败血症症状,20日龄以上以非典型症状为主。结合当地养殖和防疫状况,对当前新城疫流行形势进行了分析,旨在为业内同行提供借鉴。     

Free-range village chickens on the Accra Plains, Ghana: Their contribution to households

A cross-sectional survey investigating the contribution of free-range village chickens to household economies was carried out in four administrative districts within 60km of Accra. Answers were provided by 101 men and 99 women. Nearly all respondents claimed to keep chickens for meat, with a far smaller percentage claiming to keep them for egg production. Over 80% of respondents kept chickens to supplement their incomes. The proportion of the flock eaten varied between administrative areas (p=0.009 and p=0.027), although this was possibly a consequence of differences in consumption patterns between occupation of the respondent, land area cultivated and flock size. The proportion of chickens sold varied as a result of differences in flock size (p=0.013), the proportion sold increasing with number of birds in the flock. Respondents generally agreed that chickens could be sold without difficulty. A majority of chicken sales were from the farm gate, directly to consumers or traders. Sales were on demand or when the owner needed money. Money from the sale was kept by the owner of the chicken and the money was spent on personal needs. The proportion of the flock sold varied between administrative areas (p=0.025) and occupation of the respondent (p=0.040). Respondents describing animal production as their main occupation tended to have greater reliance on chicken sales for their income. Consideration is given to estimating the offtake from the flock and the financial contribution to the household.     

切除结膜结合淋巴组织鸡对新城疫疫苗点眼免疫反应 Ⅱ.组织学与免疫组织化学研究

60只 1日龄健康雏鸡随机分为 A、B、C三组。A组于 1日龄手术切除下眼睑结膜。A、B两组于 12日龄时结扎鼻泪管 ,用新城疫克隆 30苗点眼。C组为对照组。 2 3日龄分别采取其 CAL T和哈德氏腺 ,比较观察其组织细胞。结果 ,1日龄手术切除下眼睑结膜后造成鸡 CAL T缺失 ,点眼免疫后 ,哈氏腺的免疫细胞也较正常免疫鸡少 ,而正常接种 ND克隆 30 (B组 )后 ,CAL T发生早 ,生长快 ,淋巴细胞数量多 ,故本实验证实 CAL T对哈氏腺免疫细胞的数量与成分有一定的调控作用。 CAL T缺失鸡是研究黏膜免疫系统比较理想的模型     

Local chicken production system in Malawi: Household flock structure,dynamics, management and health

Household flocks of scavenging chickens were monitored from August 2002 to August 2003 in 27 villages in Lilongwe, Malawi. The objective was to evaluate the local chicken production system by investigating flock structure, utilization, management and constraints. Farmers and researchers jointly obtained data on household flocks. Mean flock size was 12.9, with a range of 1–61 chickens. The flock dynamics of chickens over 8 weeks old constituted 91% migrating out of flocks and 9% into the flocks. Primary functions based on flock dynamics were, in order of importance, household consumption, participation in socio-cultural ceremonies, selling, exchanging breeding stock and gifts. Of the flock exits, 43.9% were due to losses from diseases, predation and theft. Most flocks (85%) were housed in human dwelling units. Scavenging was the main source of feed. The majority (77.6%) of farmers supplemented their chickens erratically with energy-rich feeds, mostly maize bran. Most supplementation took place during the cold-dry season. Village chicken production offers diverse functional outputs but faces animal health (diseases, parasites, predation) and management (feeding) constraints, which require an integrated intervention approach at community and household level.     

Free-range Village Chickens on the Accra Plains, Ghana:Their Husbandry and Productivity

A cross-sectional[4pc] survey investigating husbandry and productivity of free-range village chickens was carried out in four administrative districts within 60km of Accra. Responses were provided by 101 men and 99 women. The mean (SD) household flock size was 28.7 (25.97) and the median was 20. The factors included in the final model investigating variance in flock size were sex of the respondent (p=0.011), administrative area (p=0.004), the numbers of members in the household (p=0.017) and the number of cattle, sheep and goats owned by the household (p=0.031). Chickens were owned by individual members of the household, but women and children were the predominant providers of care for chickens. All respondents described their chickens as scavengers that were provided with supplementary feed, and over 80% of respondents named maize as a supplementary food source. Approximately 50% of respondents claimed difficulty in providing supplementary feed, with the degree of difficulty varying between administrative areas (p<0.001). A majority of respondents (approximately 65%) claimed that their chickens laid 3–4 clutches of eggs per year. Over 70% of respondents estimated that each clutch contained 10–20 eggs, and approximately 70% of respondents estimated that 75% of the eggs hatched. Opinions on mortality varied, but 60% of men and 70% of women estimated that between 50% and 75% of both chicks and adult birds died each year. Approximately 80% of respondents named Newcastle disease as the most important health issue. The opportunities for and consequences of controlling Newcastle disease are discussed.     

Characterization of Newcastle Disease Viruses Isolated from Chickens and Ducks in Tamilnadu,India

During 1993, outbreaks of Newcastle disease occurred on many farms in Tamilnadu, India. Six Newcastle disease virus (NDV) isolates were obtained from the chickens on five different farms and from the birds on one duck farm during outbreaks of the disease. All the isolates were characterized as velogenic, based on the mean death time, intravenous pathogenicity index, intracerebral pathogenicity index (ICPI), stability of haemagglutinin at 56°C, agglutination of equine erythrocytes, haemagglutination elution pattern and adsorption of haemagglutinin by chick brain cells. The isolate obtained from ducks resembled a group D strain, based on its ICPI and its reaction with a panel of monoclonal antibodies. The other five NDV isolates obtained from chickens were placed in groups B(1), C1(2) and D(2) on the basis of their binding patterns with the panel of monoclonal antibodies. In challenge experiments, it was found that LaSota vaccine provided 100% protection against each of these field isolates and against a local NDV strain obtained from the Institute of Veterinary Preventive Medicine, Tamilnadu, India, while unvaccinated chickens succumbed to challenge. The possible origin of epizootic viruses causing outbreaks in vaccinated flocks is discussed.     

藏鸡胚死亡曲线分析研究

本文通过对四批藏鸡胚死亡曲线进行统计,分析出：引起藏鸡胚死亡的原因除种鸡的健康状况、种蛋品质、种蛋保存外,主要是高海拔低压缺氧环境和后期相对湿度较低造成的。从而为提高藏鸡种蛋孵化率提供理论依据。     

Antigenetically Unusual Newcastle Disease Virus from Racing Pigeons in India

Newcastle disease virus isolated from an outbreak in racing pigeons in India was found to be velogenic, based on the mean time to death in 10-day-old embryonated hen's eggs, the intravenous pathogenicity index in 6-week-old chickens and the pathogenesis in chickens and pigeons. The virus induced disease in chickens without prior adaptation in chickens. The virus was antigenically unusual since it could not be grouped with the available panel of monoclonal antibodies at the World Reference Laboratory for Newcastle disease, UK. However, commercially available lentogenic and mesogenic vaccines provided 100% protection to chickens against this antigenically unusual NDV.     

Response of Chickens to Infection with Newcastle Disease Virus Isolated from a Guinea Fowl

An isolate of Newcastle disease virus obtained from a guinea fowl was characterized as a viscerotropic velogenic strain based upon pathogenicity index studies. Following inoculation of the viral isolate oronasally into 3-week-old chickens, clinical signs appeared after an incubation period of 4–5 days and included dullness, depression, dyspnoea, diarrhoea and leg paralysis. The virus caused a mortality of 56% with haemorrhages at the tip of the glands of the proventriculus and caecal tonsil. Histopathological changes were prominent in the lymphoid organs, being characterized by depletion, degeneration and necrosis of the lymphoid tissues. The brain was the first organ affected, with changes being noticed 3 days after infection. Isolation of virus from various organs was more frequent from 5 to 10 days after infection, but the virus persisted in some of the organs until 21 days after infection. In spite of the high mortality, a good immune response was elicited by the isolate, as was evident from the antibody titre.     

中药复方散剂对肉鸡生长及鸡新城疫灭活油苗免疫效果的影响

将玉屏风散、十全大补汤、六味地黄丸三个中药复方散剂分别按1%剂量添加到科宝快大型白鸡日粮中, 于雏鸡14日龄, 按0.5 ml/只剂量肩部肌肉注射鸡新城疫灭活油乳剂疫苗, 即日起饲喂上述饲料, 并按40 mg/kg剂量胸肌注射环磷酰胺,每天1次, 连续3天; 免疫后第10天、 20天、 30天采血检测鸡新城疫HI抗体效价,观测鸡增重情况,免疫后第15天、 25天检测血清总蛋白含量.实验结果表明,玉屏风散、六味地黄丸能显著提高鸡新城疫HI抗体效价(P<0.05),十全大补汤的作用不明显;玉屏风散、十全大补汤能显著增加肉鸡体重(P<0.05),六味地黄丸的作用不明显,实验组鸡死亡率均降低;玉屏风散、十全大补汤能显著提高血清总蛋白含量(P<0.05),六味地黄丸的作用不明显.     

新城疫基因工程疫苗的研究与应用进展

新城疫是当今世界上最严重的家禽传染病之一,特别是对养鸡业可造成重大经济损失,被世界动物卫生组织（OIE）列为必须报告的传染病。新城疫的主要防控手段仍是免疫接种,虽然传统的灭活疫苗和弱毒疫苗在疫病的控制中发挥了巨大作用,但存在着毒力返强、散毒和免疫期短等问题,不利于疫病的控制和消灭。论文论述了国内外应用现代分子生物技术对新城疫亚单位疫苗、重组活载体疫苗、DNA疫苗、新城疫病毒载体疫苗的研究和应用情况,展示了基因工程疫苗良好的应用前景。