Suarez Martinez, Juan Carlos (2021-04). Impact of Live Coccidiosis Vaccine on Intestinal Morphology, Performance, and Vitamin D Status of Broilers: Use of Dietary Supplementation of Animal Feed Grade Sodium Bisulfate and 25-Hydroxycholecalciferol. Doctoral Dissertation.
Thesis
Studies were conducted to determine the extent to which animal feed grade sodium bisulfate (SBS) can help ameliorate the detrimental effects of coccidiosis in broilers. Four trials were conducted to establish a working foundation for SBS mode of action and differences between twenty-five hydroxycholecalciferol (25-OH-D3) vs D3 in broilers subjected to a live coccidiosis vaccine challenge. Previous research indicates the use of 25-OH-D3 as replacement or partial replacement of cholecalciferol (D3) in broiler diets can result in significant differences in performance and bone mineralization. This series of studies analyzed the impact of a 2X recommended dose coccidiosis vaccine challenge on vitamin D status, intestinal morphology, performance and bone mineralization in broilers. Studies revealed a consistent performance advantage from the dietary inclusion of 0.3 and 0.4% of SBS. Increasing SBS in the diet reduced (P < 0.001) feed pH and increased sodium and sulfur content (P < 0.001) of the diet. SBS didn't appear to modulate intestinal pH and similar performance advantages (higher body weights, improved feed conversion) can be expected when using animal feed grade sodium bisulfate or potassium bisulfate vs Control. Intestinal morphology was negatively modulated under the current coccidiosis vaccine challenge. SBS fed to broilers under coccidiosis vaccine challenge significantly reduced crypt depth compared to Control suggesting improved intestinal integrity. Vitamin D status can significantly (p<0.05) be impacted by a 2X coccidiosis vaccine challenge. Malabsorption syndrome associated with coccidiosis challenge was observed during the trial which resulted in significantly lower bone mineralization, and serum 25-OH-D3 concentration in birds fed a control diet. The results suggest the use of dietary 25-OH-D3 compared to inclusion of D3 alone provides a significantly improved safety margin for performance and bone mineralization. The results of this research effort provide practical information for the poultry industry as it relates to nutritional strategies that could be further studied as means to maintain performance under coccidiosis vaccine and offer flexibility in feed formulation.
