ABSTRACT This study examined the effects of lavender essential oil on performance, meat quality, microbial load, fatty acid profile and gut microbiota in quails. In the study, 200 quails (Coturnix coturnix Japonica) were divided into 4 groups and 5 subgroups. The groups consisted of a control group (0 mg/kg feed) and three lavender essential oil groups, namely Lav125 (125 mg/kg feed), Lav250 (250 mg/kg feed), and Lav500 (500 mg/kg feed). In terms of body weight change, Lav500 group had the best results after the control group (p>0.05). It was observed that, compared to the control group, pH levels were high (p<0.05) in Lav250 and Lav500 groups on the 9th day of storage. The effect of storage time on malondialdehyde (MDA) was used as a parameter of lipid peroxidation in meat, and the Lav250 and Lav500 groups presented lower concentrations as compared to the control group (p<0.05). In this study, the addition of lavender essential oil to the diet enriched the concentrations of n-3 and n-6 polyunsaturated fatty acids (PUFA). Moreover, the height of villi in the duodenum and jejunum, and consequently absorption, increased significantly in the Lav500 group as compared to the control group. The concentration of MDA, a blood serum antioxidant enzyme, decreased with the addition of lavender oil. Additionally, lavender essential oil added to quail diets was observed to increase the number of Lactobacillus spp. (probiotic bacteria) colonies (p<0.05).

ABSTRACT Fucoxanthin is a major carotenoid found in marine brown algae. This study investigated the impact of fucoxanthin on the growth performance, antioxidant metabolism and meat quality of broilers. Overall, 180 one-day-old male broiler chicks (Ross 308) were assigned to one control group (CONT) and 2 treatment groups (FUCO1 and FUCO2), with six replicates of 10 birds each. The CONT, FUCO1 and FUCO2 birds were fed a basal diet supplemented with 0, 100 and 200 mg/kg of fucoxanthin, respectively. Average body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) were similar among the groups. Fucoxanthin increased catalase (CAT) and superoxide dismutase (SOD) activities and glutathione (GSH) levels (p<0.01), and reduced malondialdehyde (MDA) levels (p<0.01) in the liver, breast and drumstick tissues. The effects of fucoxanthin on drumstick yellowness (b*) on day 3 and water activity (aw) on day 5 and breast lightness (L*) on day 3 b* values days 2 and 5 were limited and variable. While fucoxanthin showed antimicrobial effect against Staphylococcus spp. in the breast meat on days 5 and 6 of storage (p<0.05), its effects at different time periods and against other microorganisms varied. In conclusion, fucoxanthin did not affect performance parameters, but had a significant impact on antioxidant metabolism, and showed a limited effect on the microbial quality of meat.