Intro=Welcome to the Ceva vaccination simulator. <line> This application will enable you to understand how to calculate the dates <line> of vaccination against Gumboro disease via the drinking water <line> based on the maternal antibody titer at day old and the type of vaccine used. <line> It is an educational tool that cannot replace the vaccination date calculation performed by <line> the software delivered by Elisa serological kit manufacturers.&


&Type=Enter your type of birds, broilers or layers. <line>  <line> The difference in growth rates between these two races <line> influences the decline rate of maternal antibodies <line> against Gumboro viruses. <line>  <line> It is generally considered that the maternal antibody half-life <line> is 3.5 days in broilers <line> and 5.5 days in layers.&

&Titre=This is the mean maternal anti-Gumboro virus antibody titer <line> calculated after ELISA serology tests over 20 chicks <line> picked out randomly <line> (one chick per crate) at day 1. <line>  <line> For reliability purposes, Ceva recommends <line> to use not less than 20 chicks for the calculation <line> of the vaccination date.&

&VAriation=Enter the coefficient of variation value as it appears <line> on the serological test. <line>  <line> This value is a measure of maternal antibody <line> titer heterogeneity . <line>  <line> A value is considered homogeneous when inferior to 30%25, <line> heterogeneous between 30%25 and 70%25, <line> and highly heterogeneous above 70%25.&


&Virus=Enter the type of Gumboro disease that affects your farm. <line> A classical virus will only result in substandard <line> economic performance and low mortality. <line> It can be combated with “Intermediate” vaccines <line> such as Cevac Gumbo L, or Intermediate Plus vaccines <line> such as Cevac IBD L. <line>  <line> A « hypervirulent » virus will cause prostration <line> and severe mortality for several days. <line> Only an « Intermediate Plus » vaccine <line> such as Cevac IBD L will be able to combat this type of virus.&


&Age=Ceva recommends a double vaccination <line> (-3 days and %2b3 days from the calculated date)  for broilers <line> if the coefficient of variation reaches or exceeds 70%25. <line>  <line> For layers, double vaccination should be systematic.&


&Mode=The « automatic » mode will let the software calculate the appropriate vaccination age(s). The operator is a mere spectator. <line> In « manual » mode, the operator is asked to enter a supposed <line> vaccination age (vaccination will then be automatically doubled <line> if the coefficient of variation is equal or higher than 70%25 <line> with broilers or if the birds are layers). <line>  <line> The operator will know the result of his/her choice <line> either by an increase in the antibody level <line> and bird protection if vaccination is duly performed, <line> or otherwise by a failure message and an explanation.&