Dose-Dependent Effects of Humic Acid Supplementation on Serum Lipid Profile and Newcastle Disease Antibody Response in Broiler Chickens

Abstract

Background/Introduction: Humic acid (HA) is a high polyphenol substance. Lipid profiling involves estimation of lipids and in broiler birds, it may be useful for optimizing nutrition and enhancing poultry performance. Immune response is a physiological reaction for the purpose of defense. Objective: The study examined the effects of varying concentrations of humic acid on broiler birds, focusing on lipid profiles and immune response. Methodology: One hundred (100) one-day-old broiler chicks were distributed into five dietary groups, each consisting of four replicates of five birds were used for the study. Treatment 1, which served as the control, utilized a basal diet without humic acid supplementation. Treatments 2 through 5 involved supplementations of humic acid at levels of 0.1 to 0.4 kg per 100 kg diet respectively. The study spanned 28 days, comprising 7 days of basal diet feeding followed by 21 days of experimental feed. Serum samples collected at the end of the experiment were analyzed for lipid profiling. Results: Birds receiving 0.1 kg HA/100 kg exhibited the lowest significant serum cholesterol (24.75 ± 0.42 mmol/l; p<0.05) compared to the control (25.88 ± 0.75 mmol/l). Immune response, measured via Hemagglutination Inhibition (HI) titres, peaked in the 0.2 kg group by day 28. Results indicated significant alterations in low-density lipoprotein, very low-density lipoprotein, cholesterol and high-density lipoprotein levels with increasing humic acid concentration in the diet. Birds that received 0.1 kg HA/100 kg dietary supplement exhibited a favourable lipid profile (p<0.05). The immune response of the birds showed improvement over time with humic acid supplementation in a concentration dependent manner. Diets supplemented with 0.2 kg and 0.3 kg/100 kg of humic acid showed significantly (p<0.05) increased immune response, consistently performing better than those of the birds on the basal diet throughout the duration of the study. Conclusion: The study concluded that varying concentrations of humic acid in the diet of broiler birds significantly influenced their lipid profiles and had positive impact on immune response.