Published in Scientific Works. Series C. Veterinary Medicine, Vol. LXVIII, Issue 1
Written by Alexandra OPRESCU, Aurel VASIU, Carmen Dana ȘANDRU, Diana OLAH, Florina MARIAN, Marina SPÎNU, Emoke PALL, Gheorghiță DUCA, Mariana RUSU, Ioan Liviu MITREA
Marek’s disease (MD) is highly economically impacting viral disease in chickens aged 4 weeks - 4 month. Various hypotheses were posed to explain its recurrent epidemiology and increasing virulence over the years. This study aimed at comparing the epidemiological indicators of two confirmed Marek’s disease episodes (DIVA Real Time PCR) in two different series of Isa Brown pullets hatched one week apart on the same farm. The data indicated an increasing mortality due to MD from week 6 towards week 14, from 0.28 to 2.72% in the first series and 0.07 to 1.43% in the second one, with a cumulative mortality 3.26% and 2.28% respectively. There were no statistically significant differences between the weight gains of the two series on week 14 (peak of MD mortality), but it decreased in the first series (1398.7g versus 1478.00 g respectively) by week 16. Although the two episodes significantly differed in mortality (p<0.05), except a slight variation of the size of the flock, no other circumstances could have been identified as influential causes, the variability being attributed to differences in viral pathogenicity.
[Read full article] [Citation]
