Dynamics of thymol dietary supplementation in quail: linking bioavailability and effects on total fatty acids of egg yolk and performance traits

FERNANDEZ, M. E.; MARIN, R. H.; TARTAGLINI, L.; KEMBRO, J. M.; LABAQUE, M. C.

Campinas, San Paulo

Conferencia; Poultry Science Association Latin American Scientific Conference; 2018

Poultry Science Association

Phytogenic additives such as thymol (THY) are encountering growing interest in poultry production . Measuring bioavailability of supplemented compounds is a key element for understanding how they modulate beneficial effects on animal body. Herein, we simultaneously assessed changes in THY concentration and total fatty acids (FA) of the egg yolk induced along 28d of THY dietary supplementation (DS) and 21d after discontinuation of supplementation (AS). THY eliminated through feces, female performance and physical characteristics of eggs were also monitored in both DS and AS periods . Fifty adult female quail were randomly assigned to 1 of 5 dietary treatments: CON (basal diet), VEH (basal diet + ethanol), THY2, 4 and 6.25 (basal diet + 2, 4, 6.25g of thymol/kg of feed, respectively). THY concentration in egg yolk and feces was determined at 2, 9, 16, 26d of DS and 17d AS . Female performance and characteristics of eggs were measured at 0, 7, 14, 28d of S and 21d AS . GLMMs and Fisher tests were used to detect differences at P < 0.05. In egg yolks, THY concentration increased along DS time and decreased AS . Moreover, THY concentration was higher in THY4 and THY6 .25 compared with THY2 at all time periods evaluated . These changes were accompanied by reduced 16:0 and 18:0 concentrations achieved by 28d of DS in THY2 and 14d of DS in THY4 and THY6 .25 . However, at 21d AS the aforementioned effect on 16:0 disappeared in all diets, but 18:0 was found still lower in THY4 compared with the other treatments . Throughout DS THY4 and THY6 .25 modulated polyunsaturated FA increments of higher magnitude than THY2, which remained increased at 21d AS. Specifically, all diets increased 22:6 and 20:5 by 7d of DS, but only THY4 y THY6 .25 showed higher concentrations of 18:3 and 20:4 by 14d of DS . In addition, THY2 and THY4 required 14d for increasing 22:5, while THY6 .25 needed 7d for achieving similar changes . FA changes induced by THY are consistent with an improved nutritional quality of eggs . In feces, increased THY concentrations were detected at 9, 16 and 26d of DS in both THY4 and THY6 .25 groups . No differences between dietary treatments nor during DS and AS periods were observed in female performance and physical characteristics of eggs . Findings suggest that both the dose of THY and the duration of DS, consistently modulate THY and FA concentration in egg yolk and THY concentration in feces . Furthermore, the persistence of those effects AS is also in accordance with a dose-dependent phenomena .