Effect of Water Organic Load and Total Ammonia Nitrogen on Broilers’ Humoral Immune Response Against Newcastle Disease Virus Vaccination in Egypt

Low-quality drinking water (DW) has a negative impact on poultry immunity raising the risk of emerging infections. The current trial used experimentally contaminated broilers’ DW to study its effect on humoral immunity compared to 2 control groups. A total of 450 unsexed 1-day-old Cobb chickens were randomly allocated into 6 groups (75 birds in 5 replicates per group). DW of (T1) had 24 ppm chemical oxygen demand (COD), (T2) 12 ppm COD, (T3) 15 ppm total ammonia nitrogen (TAN), (T4) 5 ppm TAN, (T5) normal tap water (TW), (T6) TW with immunostimulant (IMU FORT®) a day before and after vaccination. Birds were subjected to the NDV DW vaccination program, serum was collected weekly, antibody (Ab) titers were measured along 6 weeks, lymphoid organs somatic indices (OSI) were evaluated after carcass evisceration at the end of the trial (42nd day), and Postmortem lesions were examined. Groups showed differences in Ab titers however, the 3rd and 6th weeks showed significant differences (p≤0.05), at the 3rd week T3 titers were significantly higher than T1, T2 but lower than T4, T6, and at the 6th week T6 titers were significantly higher than T1, T3, T4 but T5 was significantly lower than T3. The lowest OSI was in T3 which records 0.475, 0.133, 0.101 for thymus, bursa, and spleen, respectively while T6 was the highest. Broilers’ DW which has a high organic load (COD) and TAN, significantly decreases Ab titers and OSI. Both good quality DW and immunostimulant supplementation have a positive effect on NDV vaccines’ immune response.