TY - JOUR
T1 - Modeling the impact of newcastle disease virus vaccinations on chicken production systems in northeastern madagascar
AU - Annapragada, Akshaya
AU - Borgerson, Cortni
AU - Iams, Sarah
AU - Ravelomanantsoa, M. Ando
AU - Crawford, Graham C.
AU - Helin, Marika
AU - Anjaranirina, Evelin Jean Gasta
AU - Randriamady, Hervet J.
AU - Golden, Christopher D.
N1 - Publisher Copyright:
© 2019 Annapragada, Borgerson, Iams, Ravelomanantsoa, Crawford, Helin, Anjaranirina, Randriamady and Golden.
PY - 2019/9/1
Y1 - 2019/9/1
N2 - Chickens are a key source of nutrition for rural Malagasy communities. Due to high endemic rates of Newcastle disease, it remains challenging to raise sustainable chicken flocks as a consistent food source. Here, we explore the impact of triannual Newcastle disease virus (NDV) vaccine interventions on the growth and herd immunity acquisition of Malagasy chicken flocks. Between 2011 and 2018 we collected longitudinal data to assess the population dynamics of chicken populations in remote Malagasy communities. In 2016, we launched a pilot campaign for vaccination in six rural communities to determine the impacts on chicken survivorship and productivity. We used these data to specify a mathematical model of realistic Malagasy chicken population dynamics under a triannual vaccination regime. The mathematical model represents an extension to conventional SIR models that allows for modeling the impact of specific vaccinations on chicken flock dynamics, rather than estimation of parameters. Understanding chicken population dynamics is important for realizing the potential for domestic chicken flocks to serve as sustainable food sources. The results suggested that vaccination coverage of at least ∼40% is necessary over 5+ years to achieve population doubling, while complete herd immunity may not be possible given the short duration of effectiveness of vaccination, and the high levels of births and deaths in the chicken flocks.
AB - Chickens are a key source of nutrition for rural Malagasy communities. Due to high endemic rates of Newcastle disease, it remains challenging to raise sustainable chicken flocks as a consistent food source. Here, we explore the impact of triannual Newcastle disease virus (NDV) vaccine interventions on the growth and herd immunity acquisition of Malagasy chicken flocks. Between 2011 and 2018 we collected longitudinal data to assess the population dynamics of chicken populations in remote Malagasy communities. In 2016, we launched a pilot campaign for vaccination in six rural communities to determine the impacts on chicken survivorship and productivity. We used these data to specify a mathematical model of realistic Malagasy chicken population dynamics under a triannual vaccination regime. The mathematical model represents an extension to conventional SIR models that allows for modeling the impact of specific vaccinations on chicken flock dynamics, rather than estimation of parameters. Understanding chicken population dynamics is important for realizing the potential for domestic chicken flocks to serve as sustainable food sources. The results suggested that vaccination coverage of at least ∼40% is necessary over 5+ years to achieve population doubling, while complete herd immunity may not be possible given the short duration of effectiveness of vaccination, and the high levels of births and deaths in the chicken flocks.
KW - Animal-source foods
KW - Food security
KW - Malnutrition
KW - Poultry
KW - Sustainable agriculture
KW - Vaccination
UR - http://www.scopus.com/inward/record.url?scp=85073163966&partnerID=8YFLogxK
U2 - 10.3389/fvets.2019.00305
DO - 10.3389/fvets.2019.00305
M3 - Article
AN - SCOPUS:85073163966
SN - 2297-1769
VL - 6
JO - Frontiers in Veterinary Science
JF - Frontiers in Veterinary Science
IS - SEP
M1 - 305
ER -