Establishing the Tolerability to Turkeys of Nonanoic Acid at Practical Levels of Use as a Feed Flavoring

Objective: Nonanoic acid (NA) is one of a series of straight-chain aliphatic alcohols, aldehydes, acids and their derivatives with a well-documented history of use as a synthetic flavoring in human food. As part of a safety evaluation of NA for use as a flavoring in animal feed, an experiment was conducted to evaluate the ability of turkeys to tolerate NA at levels relevant to practical feeding practices. Materials and Methods: A total of 594-day-old BUT Premium turkeys (300 males and 294 females) were allocated at random to 40 floor pens containing either 15 males or 13 to 15 females. Poults were fed one of 4 treatment diets in crumble (0 to 14 days) or pellet (15 to 59 days) form containing 0 (control), 100, 300 or 1000 mg NA/kg complete feed for 59 days. General health and performance were monitored for the duration of the study. At days 57 and 59 of age, blood samples were taken and birds were sacrificed and necropsied for histopathological examination of the digestive tract. Significant differences were considered at P ≤ 0.05 and near-significant trends at P ≤ 0.10. Results: NA had no effect on mortality (Pχ2 = 0.54), average daily feed intake (ADFI) (P = 0.11), average daily gain (ADG) (P = 0.12) or feed conversion ratio (FCR) (P = 0.45) in poults over the 56-day feeding period. No treatment-related effects on blood parameters or tissue pathology were observed. Conclusion: The results of the study support the safety and tolerance of NA to turkeys at dietary levels of up to 1000 mg/kg which will provide a considerable margin of safety compared to anticipated practical conditions of use as a feed flavoring.