EPIDEMIOLOGY OF NEWCASTLE DISEASE IN VILLAGE CHICKENS IN BAUCHI STATE, NIGERIA
Newcastle disease (ND) is considered as a major constraint to village chicken production in Africa. A study on the epidemiology of ND in village chickens was conducted in nine communities randomly drawn from nine Local Government Areas (LGAs) in Bauchi State to asses: the importance of NDto village chicken farmers using the participatory epidemiological tools; the prevalence of ND from monthly disease reports, the prevalence of ND virus (NDV) and seroprevalence of ND; andacceptance among farmers of ND vaccination and its benefits. A sixty Monthly Disease Reports (June 2010-May 2015) submitted by the eight Area Veterinary Offices covering the studied communities were examined at the office of the Director Veterinary ServicesBauchiState for cases of ND disease in poultry. Staff from the Veterinary Department was assigned the duty of inviting farmers in each community for a focus group discussion (FGD) to assessthe importance of ND among the common diseases of village chickens in their community. Participants of FGDs also selected eight households (HHs) in each community. From these HHs samples of blood and cloacal swabs for detection and determination of prevalence of antibodies and antigen of ND virus (NDV) were collected; chickens were vaccinated against ND to assess acceptance and benefit of vaccination. Also, volunteering members from these HHs answered questionnaire on village chicken management. Haemagglutination inhibition test (HIT) was used to detect ND antibodies from sera extracted from the blood collected from village chickens. Conventional Reverse Transcriptase Polymerase Chain Reaction was used to detect NDV. Cloacal swabs that tested positive for ND were inoculated into 9-11 day old embryonatedchicken eggs to isolate NDV. The prevalence of reported cases of ND in poultry was 11.6%. Newcastle disease was mostly reported during the cold season (October-March) with the highest seasonal index of 44.4% and an odds ratio of 6.6 in November. The proportional piling scores for ND in Chinade was 146/249 (69.9%), in Jalam 35/105 (32.4%), in Udubo 183/261(70.1%), in KafinMadaki 149/244 (61.1%), in Gongoro 80/183 (43.7%), in Dass 175/270 (64.8%), in Kutaru 126/243 (50.8%) and in Toro 173/288 (60.1%). The pair wise ranking score for ND in Chinade was 4/5, in Jalam 5/6, in Udubo 5/6, in KafinMadaki 6/7, in Gongoro 4/5, in Dass 3/4, in Kutaru 5/6 and in Toro 4/5. Most of the respondents 71 (98.6%) had experienced outbreak of ND in their flock within the last six months with greater than 50% mortality of 54 (75%) chicken during the cold season. Vaccination against ND was not practiced by any of the respondents. The seroprevalence of ND was 36.4%;and the prevalence of NDV was 29.9%. Three isolates (3/20; 15%) were obtained from cloacal swabs of chickens from Toro. Vaccination against ND was first carried out on 1139 village chickens in 72 HHs and the second vaccination was carried out on 814 chickens in 54 of the 72 HHs. Rejection of vaccination was experienced in 8 HHs (8/72; 11.11%). Additional ND vaccines were given to 746 chickens in 64 HHs that were neighbours of the initial participants. A proportional piling scores given by 68 participants was 100% (340/340 beans shared) for acceptance of vaccination against ND, while, a score of 92.7% (338/365 beans shared) was given in favour of ND vaccine being beneficial to farmers of village chickens. The study concludes that ND is an important disease of village chickens that is widespread and cannot be controlled by the current management practices. Vaccination of village chickens against ND was accepted and beneficial to farmers. The study recommends characterization of local strains of NDV by National Veterinary Research Institute, Vom; prioritization of ND by Bauchi State for state wide immunization and routine vaccination of village chickens against ND by farmers for an improvement in village chicken production.
Nigeria had an estimated human population of 177,475,986 in 2014 (The World Bank Group, 2016) with over half of its population living in poverty (NBS, 2012). The desire to end poverty and hunger; and to empower women is among the 17 goals contained in the United Nations Agenda 2030 for sustainable development goals (SDG, 2015).
Poverty refers to people earning less than $1.25 dollar a day (SDG, 2015). Hunger refers to chronic undernourishment, while, undernourishment refers to a person who cannot have sufficient food to meet his or her energy need for a period of one year (FAO, IFAD and WFP, 2015). To reduce extreme poverty requires an increase in the income of the poor above $1.25 a day. To end hunger among people requires the doubling of agricultural productivity, and access to safe, nutritious and sufficient food (FAO, IFAD and WFP, 2015; SDG, 2015) that eventually will result in food security.
Village poultry could be use to achieve poverty reduction and improvements in the livelihood of its owners; improvements in the production of these chickens are possible especially with vaccination against ND as the first step (Dolberg, 2003). Village poultry can increase household income, and reduce poverty (Pica-Ciamara and Otte, 2010). Village chicken could be used to meet the nutritional and economic welfare of resource poor people (Magotheet al., 2012). Village chickens provide meat and eggs that can be used to achieve food security.
Village chicken belongs to the species Gallus gallusdomesticus and constitutes over 96% of the rural poultry population in Africa (FAOSTAT, 2012). Rural poultry refers to chickens, ducks, guinea fowls, turkeys and pigeons (Bagnol, 2012).
Nigeria has about 182, 109,343 poultry (WAHID, 2014) most of which are rural poultry (Adene and Oguntade, 2006; Joannis et al., 2013) that could be used as a tool to end poverty and hunger.
Eradication of poverty and hunger using these chickens will not be possible due to constraints of poor nutrition, predators, disease and environmental stress (Bell, 2009). Newcastle disease (ND), the major cause of chicken mortality in Nigeria (Abdu et al., 1992), is recognized together with avian influenza, Gumboro and Fowl pox as the major constraints of village chicken production (Bell, 2009).
Wherever ND was controlled, a boost in village chicken production has been recorded due to reduced chicken mortality and increase in egg production that resulted in the hatching of more chickens (Alders, 2009).
The control of ND could result in the sales and consumption of more chickens which directly increases both income and protein of the owners of these chickens- thereby reducing both poverty and malnutrition. The owners of these chickens could trade on them to pay school fees, medical bills; buy clothes and meet other social obligations (Alders,etal., 2009).
The control of ND could stimulate interest in chicken and other livestock production. It could stimulate an interest in the control of other diseases for the benefit of the farmers, researchers and clinicians (Alders and Spradbrow, 2001)
1.2 Statement of the Research Problem
Although, Bauchi State has over 5,000,000 village chicken (Adene and Oguntade, 2006), their use as a tool to end poverty and hunger is limited by ND and other constraints (Bell, 2009).
Newcastle disease which was said to be endemic in Nigeria (Sa‟idu et al. 2006) is both a notifiable disease and a transboundary animal disease. Newcastle disease can restrict international trade in poultry and poultry products (OIE, 2012).
Even though, Nigeria as a member of world Animal Health Organization (WAHO) and (OIE) and Inter-African Bureau for Animal Resources (AU-IBAR) is obligated to submit monthly and annual disease report on OIE listed diseases and trans-boundary animal diseases (TADs) (Pan-African Resource Year Book, 2014), a review on ND reports in Nigeria showed that less than twenty percent of cases were reported by states and about fifty one percent (51.6%) of the cases were reported late (Gashash, 2009). The observation that diseases were under reported (Gashash, 2009; Tsofo, 2012; Joannes et al., 2013) makes the use of complimentary techniques like the participatory epidemiology anadjunct to disease reporting.
Newcastle disease was regarded as the major constraints limiting village chicken production in Africa and Nigeria (Spradbrow, 1988; Abdu et al., 1992). Newcastle disease is one of the two most important diseases of poultry that can cause between 50-100% mortality in a susceptible village chicken population (Ahlers et al., 2009) resulting in negative economic impact on poultry production.
Infection with lentogenic strain of ND could lead to reduction in the productivity of village chicken (Charkrabarti, 2007; OIE, 2012). Mixed infection of ND with other diseases can affect the severity ofclinical signs in village chicken (Charkrabarti, 2007; Higgins and Shortridge, 1988).
A previous serologic study of ND in village chickens by Nwakiti et al. (2010) was carried out six years ago and was restricted only to Bauchi Metropolis. A study combining serology with other techniques are needed to assess the importance, the occurrence and distribution of ND beyond the Bauchi Metropolis in Bauchi State.
Assessment of the importance of ND may require a situational analysis within the studied communities. Participatory study has been recommended as an aid to conventional epidemiology in undertaking a situational analysis and in monitoring and evaluation of a vaccination campaign (Alders and Spradbrow, 2001; Ahlers et al., 2009).
Vaccination was said to be critical to the control of ND (Nwanta, 2008). Information on vaccination of village chickens against ND is lacking in Bauchi State. To generate such information will require a pilot vaccination campaign. Involvement of farmers into such vaccination campaign could generate information on the levels of acceptance and benefits of such interventions. When such intervention is accepted by farmers in their communities, the possibility of a largescale implementation of ND control programme is high.
1.3 Justification for the Study
Village chickens have been used as a tool for poverty reduction and improvement of the nutrition of its owners (Pica-Ciamara and Otte, 2010). Nigeria and indeed Bauchi State has abundance of village chickens that could be used to attain the SDGs of poverty reduction and elimination of malnutrition and hunger (SDG, 2015).
Newcastle disease affects the production of village chickens which is the common asset of the poor (Sonaiya, 2009) that could be used to generate income or consumed to improve the nutrition of its owners. Village chickens as an asset of the poor are produced under a low input system with short term return on investment. They are used as the first rung in the ladder of acquisition of other livestock that eventually could bring social acceptance of farmers in their communities (Dolberg, 2003; Sonaiya, 2009).
A previous study on ND was restricted to seroprevalence conducted within a slaughter house in Bauchi metropolis. A holistic study of ND beyond Bauchi metropolis could enable better understanding of the epidemiology of ND in village chickens in the State.
Newcastle disease in the less virulent form can decrease productivity of village chicken (OIE, 2012). The knowledge of the distribution of NDV could provide the basis for intervention, while, characterization and tracing of the phylogeny of NDV could yield valuable molecular epidemiologic information(Aldous et al., 2001).Vaccination, the only means of controlling ND in Nigeria (Sa‟idu et al., 2006; Nwanta,etal.,2008) has not been routinely practised in village chickens; a study on acceptance by farmers following a pilot vaccination could generate information that could aid implementation of a policy on vaccination against ND and other important diseases of village chickens in Bauchi State.
This study could generate information that could improve village chicken production and make significant contribution towards attainment of the sustainable development goals of ending poverty and hunger in Bauchi State which has the fourth highest poultry population in Nigeria (Adene and Oguntade, 2006).
1.4 Aim of the Study
The aim of this work was to study the epidemiology of Newcastle disease in village chickens in Bauchi State.
1.5 Objectives of the Study
The objectives of the study were to:
- Retrospectively determine the prevalence of cases of ND in poultry from the Monthly disease reports (MDRs) in Bauchi State.
- Determine by participatory techniques the importance of ND in village chickens in some communities in Bauchi State.
- Determine the seroprevalence of ND in village chickens in some communities Bauchi State.
- Determine the prevalence of NDV in in some communities Bauchi State.
- Examine wether thecurrent way of managing village chickens could aid the control of ND in some communities in Bauchi State.
- Assess the level of acceptance of ND vaccination and its benefit among farmers of village chickens.
1.6 Research Questions
- What is the prevalence of ND in poultry in Bauchi State?
- Do communities in Bauchi State regard ND as an important disease of village chicken?
- What is the seroprevalence of ND in village chickens in Bauchi State?
- What is the prevalence of NDV in village chickens in Bauchi State?
- Does the current management of village chickens facilitate the control of ND in village chickens in Bauchi State?
- Is ND vaccination of village chickens acceptable and beneficial to farmers?
EPIDEMIOLOGY OF NEWCASTLE DISEASE IN VILLAGE CHICKENS IN BAUCHI STATE, NIGERIA