@article{fdi:010075519,
  title = {{M}ortality, disease and associated antimicrobial use in commercial small-scale chicken flocks in the {M}ekong {D}elta of {V}ietnam},
  author = {{C}arrique-{M}as, {J}. and {V}an, {N}. {T}. {B}. and {C}uong, {N}. {V}. and {T}ruong, {B}. {D}. and {K}iet, {B}. {T}. and {T}hanh, {P}. {T}. {H}. and {L}on, {N}. {N}. and {G}iao, {V}. {T}. {Q}. and {H}ien, {V}. {B}. and {P}adungtod, {P}. and {C}hoisy, {M}arc and {S}etyawan, {E}. and {R}ushton, {J}. and {T}hwaites, {G}.},
  editor = {},
  language = {{ENG}},
  abstract = {{R}aising chickens in small-scale flocks following all-in-all-out management is common in the {M}ekong {D}elta of {V}ietnam. {T}hese flocks represent an intermediate category between backyard and intensive (industrial) farming systems. {H}owever, little is known about the occurrence and burden of disease and/or mortality in such flocks, and their potential association with antimicrobial usage ({AMU}). {W}e investigated mortality, disease and weekly antimicrobial use ({AMU}) in 124 cycles of meat chicken flocks raised in 88 farms in the {M}ekong {D}elta of {V}ietnam (with a median cycle duration of 18 weeks [inter-quartile range {IQR} 17-20]). {W}e visited each farm 4 times per cycle to review data collected weekly by the farmers on clinical signs, mortality, and {AMU}. {T}he overall probability of disease and {AMU} were 0.31 (95% {CI} 0.29-0.32) and 0.26 (95% {CI} 0.24-0.28), respectively. {T}he average weekly incidence of mortality was 2.6 (95% {CI} 2.2-3.0) per 100 birds. {B}oth the probabilities of a flock experiencing disease and mortality, as well as of using antimicrobials decreased with the flock's age. {H}owever, mortality peaked at the 5-10 week period. {T}he only significant explanatory factors associated with presence of disease was the stage of production >= 5 weeks (protective) ({OR} <= 0.51). {F}actors independently associated with {AMU} (p < 0.05) were: (1) {N}umber of chickens (log) ({OR} =1.46), (2) {S}tage of production >= 5 weeks ({OR} <= 0.67) (protective), (3) {C}ao {L}anh district ({OR} 2.23), (4) {D}ensity of veterinary drug shops at commune level (log) ({OR}=1.58), and (5) {D}isease in flocks ({OR}= 1.80). {F}actors independently associated with overall increased weekly incidence of mortality (p < 0.05) were: (1) {H}igh level of education attainment (secondary education or higher) ({H}azard rate {R}atio [{HR}] =1.70), (2) number of chickens (log) ({HR}= 1.39), and (3) {S}tage of production > 5 weeks ({HR} <= 2.14). {I}n flocks reporting disease, {AMU} significantly reduced the incidence of mortality ({HR}= 0.90). {T}hese results confirm an exceptionally high mortality in chicken flocks in the area, jeopardizing the profitability and sustainability of these small-scale farming systems. {T}he data also suggest an association between nearby access to antimicrobials and {AMU}, and a high correlation of {AMU} over consecutive cycles. {T}he atomized farming landscape of the {M}ekong {D}elta, the high incidence of disease and mortality, and the unrestricted and easy access to antimicrobials present major challenges to the implementation of policies aimed at {AMU} reductions.},
  keywords = {{M}ortality ; {D}isease ; {A}ntimicrobial use ; {P}oultry ; {C}hickens ; {V}ietnam ; {VIET} {NAM} ; {MEKONG} {DELTA}},
  booktitle = {},
  journal = {{P}reventive {V}eterinary {M}edicine},
  volume = {165},
  numero = {},
  pages = {15--22},
  ISSN = {0167-5877},
  year = {2019},
  DOI = {10.1016/j.prevetmed.2019.02.005},
  URL = {https://www.documentation.ird.fr/hor/fdi:010075519},
}