EFFECTS OF SUPPLEMENTING A LAYING RATION CONTAINING RAPESEED MEAL WITH ANTIBIOTIC DRUGS ON THE FISHY ODOR AND TRIMETHYLAMINE CONTENT OF EGGS PRODUCED BY BROWN-EGG LAYERS

Two experiments were conducted to study the effects of supplementing a laying ration containing rapeseed meal (RSM) with antibiotic drugs on the fishy odor and trimethylamine (TMA) content in eggs laid by brown-egg layers. Brown-egg layers (Rhode Island Red) which had been previously found to lay eggs with a fishy odor when fed a ration containing 10% RSM were used in these studies. In exp. 1, a basal laying ration containing 10% RSM was fed to 16 groups of brown-egg layers (12 birds per group) for a pretreatment period of 4 wk. Quadruplicate groups of these birds were then allotted to each of four treatments for a period of 4 wk. These were the basal ration without supplementation with antibiotic, and the basal ration supplemented with either aureomycin (220 g/1000 kg), penicillin (55 g/1000 kg) or with sulfamethazine in the drinking water (1000 g/1000 kg). Eggs produced by birds during the last week of the pretreatment and treatment periods were scored organoleptically for fishy odor and pooled egg samp...