Biochar, zeolite and bentonite feed supplements influence broiler growth and meat yield and excreta properties

The effects of biochar, zeolite and bentonite as feed additives were evaluated in terms of performance of broiler body growth, carcass and meat yield and excreta properties. In a pen trial, broiler chickens (Cobb 500) were randomly allocated to 10 treatments (n = 20 per treatment), being fed on either a standard diet or that diet supplemented with 1, 2 or 4% w/w biochar, zeolite or bentonite for the period 12 to 46 days from hatching. The highest eviscerated carcass weight was associated with birds on 1% biochar feed. Carcass dressing percentage and weight of meat cuts was also highest in birds on the 1% biochar diet, while abdominal fat pad weight was lowest in birds on the 4% biochar diet. Pen ammon ia levels were decreased by all supplement treatments, relative to the control, while pH was increased in excreta of birds fed with biochar and bentonite supplements. Excreta C increased significantly with 2 and 4% biochar in diet, as expected, and excreta N decreased with supplement inclusion. Commercial shed trials were conducted involving bird flocks of 2800 birds per shed, maintained on either a normal diet or a 2% w/w biochar amended diet (n = 10 sheds for each treatment). Bird weight and eviscerated carcass weight were increased by 4.9 and 5.3%, respectively, with the dietary biochar addition. Likely mechanisms for the noted effects are discussed. © Verlag Eugen Ulmer, Stuttgart.