Title: Effect of in ovo vaccination and anticoccidials on the distribution of Eimeria spp. in poultry litter and serum antibody titers against coccidia in broiler chickens raised on used litter Authors
|Lee, Kyung -|
|Jang, Seung -|
|Page, Marc -|
|Bautista, Daniel -|
|Pope, Conrad -|
|Ritter, Donald -|
|Lillehoj, Erik -|
|Neumann, Anthony -|
|Siragusa, Gregory -|
Submitted to: Research in Veterinary Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 30, 2014
Publication Date: N/A
Interpretive Summary: Avian coccidiosis is a major parasitic disease of industry concern worldwide. Afflicted birds exhibit nutrient malabsorption, decreased body weight gain and in severe cases, mortality. In the United States alone, the cost of anticoccidial medication has been assumed to be US $127 million annually. Developing a logical vaccine to control coccidiosis is important. In this report, ARS scientists collaborated with scientists from a poultry vaccine company to evaluate the effects of various field programs that are being used to control coccidioisis. The results showed that the type of disease management program influences the outcome of disease, and drugs usually decreased host immune response to the parasites. This information will enhance our ability to develop logical coccidiosis control strategies for the poultry industry.
Technical Abstract: The present study reports the effects of various field anticoccidial programs on the distribution of Eimeria spp. in poultry litter and serum antibody titers against coccidia in broiler chickens raised on used litter. The programs included in ovo vaccination and various medications with either chemicals, ionophores, or both. In general, serum samples from these chickens showed anticoccidial antibody titers when tested at days 7 and 14 post hatch with the peak response at day 43. Serum anticoccidial titers were highest in birds fed a non-medicated diet compared with those vaccinated or fed medicated diets. The total number of Eimeria oocysts and the composition of Eimeria spp. present in the litter samples from different treatment groups varied depending on the type of anticoccidial program. Oocyst counts in general ranged from 3.7 × 103 to 7.0 × 104 per g of litter. Importantly, both morphological and molecular typing studies revealed four major predominant Eimeria spp., E. acervulina, E. maxima, E. praecox, and E. tenella in the litter samples. Collectively, these results indicate that the field anticoccidial programs influenced the type and abundance of Eimeria spp. present in the litter samples, and also modulated host immune response to Eimeria.