Evaluation of the efficacy of vaccine in coccidiosis in broilers in New Valley governorate

Abstract

Avian coccidiosis is the primary parasitic disease that afflicts poultry and is responsible for significant economic losses. Vaccination has emerged as a viable alternative to chemical treatments for controlling broiler coccidiosis and has shown considerable potential for mitigating its impact. This study aimed to evaluate the effectiveness of Fortegra ® vaccination in controlling coccidiosis in broiler chickens. A total of 245 unsexed one-day-old broiler chickens obtained from Masr poultry were divided into seven groups, with 35 birds in each group. Four groups (GA1, GA2, GA3, and GA4) were vaccinated with Fortegra ® while three groups (GB1, GB2, and GB3) served as non-vaccinated controls. At 6 days of age, all chicks in the vaccinated group were administered Fortegra ® , while all groups except GA3 and GB3 were infected with coccidia at day 22. The results showed that vaccination did not prevent infection but resulted in lower lesion scores compared to the conventional and control groups. Body weight in the vaccinated group (GA) was lower than that of the non-vaccinated (GB) groups. Microscopic examination of fecal samples collected at different ages confirmed coccidia infection in all experimental groups. Broiler intestinal mucosa scrapings revealed typical forms of Eimeria species, leading to bloody diarrhea and petechial hemorrhage. After a 72-hour period at 30ºC with forced aeration, sporulation occurred, and oocysts were stored in a potassium dichromate solution. Microscopic examination confirmed the presence and shape of oocysts, and experimental samples displayed a 500 bp amplicon size specific to Eimeria spp. While Fortegra ® vaccination did not prevent infection, it resulted in lower lesion scores compared to the conventional and control groups. Thus, vaccination may serve as an effective approach for controlling coccidiosis in broiler chickens, but further research is necessary to optimize vaccination protocols and evaluate its long-term effects on broiler production.