Effects of dietary supplementation with thymol on the lipid composition during embryonic development in quail (Coturnix japonica) eggs.

FERNANDEZ M. E.; MARIN R. H.; ZUNINO, P.; LABAQUE, M. C.

Congreso; 2015 Poultry Science Association Annual Meeting; 2015

Diet composition affects the quality and quantity of nutrients, particularlyfatty acids (FA) and antioxidants that females allocate for eggformation. Polyunsaturated FA (PUFA), some of which are deficient indiets of captive animals, are crucial components of yolk and particularlyprone to oxidative damage, that generates the loss of nutrients forembryonic development and influences the quality of eggs for humanconsumption through the formation of reactive species. Thymol (THY)is a natural antioxidant that could help maintain the degree of unsaturationof yolk FA. The present study evaluated the effect of THY feedsupplementation on the FA profile (total FA (T), and FA of phospholipid(PL) and triglyceride (TG) fractions) in quail egg yolk during embryonicdevelopment. Adult female quail (n = 24) were randomized to 1of 2 treatments: control or 6.25g of THY per kg of supplemented feed.Eggs were collected daily and incubated to obtain samples at 3 stagesof embryonic development: 0, 4 and 16 d of incubation (no development,early- and final- development, respectively). Methyl esters of T,PL and TG of the yolk were analyzed by GC-MS. ANOVAs and Fishertests were used to detect differences at P < 0.05. At 0 d of incubation,eggs from THY showed higher relative percentages of linolenic in Tand TG, docosahexaenoic in T, and arachidonic in TG fractions, andlower saturated FA/PUFA and stearic/oleic ratios in T and TG fractionscompared with their controls. At later developmental stages, no differenceswere found on FA profiles. The initial FA changes induced by THYsupplementation are consistent with an improved nutritional quality ofnewly laid eggs that because of the lack of treatment differences duringdevelopment, the embryo would be capitalizing. On the other hand, froma human consumption perspective, if the observed THY effects on FA ofnewly laid eggs generalize to laying hen strains, the use of THY wouldbe advisable for the production of healthier eggs.