Effects of three feed disinfectants on microbial population and nutritional value of broiler diets

Feed hygienic quality can influence growth performance, health status, and production efficiency in broiler chickens. This study evaluated three chemical feed disinfectants differing in active ingredients-formaldehyde (formalin), a formaldehyde-propionic acid blend (Termin Gold®), and a hydrogen peroxide-silver nanoparticle formulation (Nanosil Feed & Air®)-and compared direct addition versus premix application on feed microbial quality, nutrient composition, and broiler performance. A total of 480 one-day-old male Ross 308 broiler chicks were used in a 35-d trial and allocated to 6 dietary treatments (4 pens/treatment; 20 birds/pen): control (no disinfectant), Termin Gold® added to the final diet, Nanosil Feed & Air® added to the final diet, formaldehyde added to the final diet, formaldehyde applied as a premix (prepared 7 d before use), and Termin Gold® applied as a premix (prepared 7 d before use). Growth performance was recorded weekly. Chemical composition of starter (d 0-10), grower (d 11-24), and finisher (d 25-35) diets was analyzed. Microbiological evaluations included total bacterial count, fungal count, and coliform population. From week 2 onward, premix-applied formaldehyde and Termin Gold® improved BW gain, feed intake, and feed conversion ratio, particularly during the grower and finisher phases. Disinfectant treatment did not adversely affect proximate diet composition. All disinfectants reduced bacterial contamination in starter and grower feeds, with formaldehyde showing the greatest effect in grower diets. Fungal counts were largely unaffected, whereas formaldehyde-based treatments produced the lowest coliform counts during the grower and finisher phases. In conclusion, both active ingredient and application method influenced disinfection efficacy. Premix application of formaldehyde- and formaldehyde-propionic acid-based disinfectants improved feed hygienic quality and broiler performance without compromising nutritional value.