Comparison of the application parameters of coccidia vaccines by gel and spray

Coccidiosis is an economically significant enteric disease caused by Eimeria species. Control of the disease is achieved through various means, including chemical anticoccidial drugs, ionophore antibiotics, and vaccination. Differences between the vaccines include the number of oocysts per dose (varying by as much as tenfold between vaccines), attenuation status of the oocysts, and the species present within the vaccine. Coccidia vaccines are typically administered via spray cabinet to day old chicks; however, a new gel-based delivery system that claims to elongate preening time and increase oocyst ingestion has been introduced and is specifically recommended for certain low dose vaccines. The purpose of this trial was to compare the application properties between high and low oocyst dose vaccines administered via gel and spray delivery systems to determine if application systems could potentially affect application success. The vaccines were mixed into gel and spray diluents per manufacturer's instructions, and samples were taken to assess how well the oocysts remained in suspension. Gel and spray application patterns were assessed by measuring the size and number of droplets applied onto a plexiglass sheet in a chick basket. Different size droplets were collected and oocyst enumeration and speciation were performed. Results show that no settling occurred after mixing in either diluent. As expected, the number of oocysts per droplet increased as droplet size of the spray administration increased but stayed constant in the uniform droplet size of gel administration. There was also a consistent number of oocysts found in each of the sections across the plexiglass sheet. Taken together, these data will aid poultry producers in deciding which delivery system will provide the best application in their production system.