Dietary thyme, gunnera, and liquorice powders enhance antioxidant status, gut-cardiopulmonary function, lipogenesis-related gene expression, and telomere length in broiler chickens.

The present study evaluated variations in growth performance, intestine morphometry, cardio-pulmonary function, hepatic lipogenesis, and telomere dynamic of broiler chickens as influenced by dietary supplementation of gunnera, thyme, and liquorice. The experiment was conducted in a high-altitude region (2,100 m) with a total of 500 one-day-old chicks (Ross 308). Five dietary treatments included a control diet, the control + gunnera powder (GP), the control + thyme powder (TP), and the control + liquorice powder (LP). TP and GP were supplemented at 7.5 g/kg and LP was supplemented at 3.75 and 7.5 g/kg. Results showed that weight gain, feed conversion ratio (FCR), and villus dimensions (height, width, and absorptive surface area) in the duodenum, jejunum, and ileum were improved by all herb supplements when compared to the control (P < 0.05). Herbal supplements elevated circulatory levels of nitric oxide (NO), and ferric-reducing antioxidant power (FRAP) whereas they lowered circulatory levels of malondialdehyde (MDA), triacylglycerol (TAG), total cholesterol (TC), and low-density lipoproteins cholesterol (LDL). Phytobiotic supplementations were associated with a decline in the T, R, and S wave amplitudes of the Lead II electrocardiogram (ECG) (P < 0.05). Dietary supplements caused an up-regulation of inducible nitric oxide synthase (iNOS), superoxide dismutase 1 (SOD1), and glutathione peroxidase (GPX) but decreased the expression of key hepatic lipogenic enzymes (fatty acid synthase (FAS) and hydroxy-methylglutaryl-CoA reductase (HMGCR) (P < 0.05). Chickens consumed herbs had higher telomeric DNA quantity in the liver relative to the control counterparts (P < 0.05). In conclusion, while the phytobiotics suppressed lipogenesis, they improved antioxidant defense, intestinal and cardio-pulmonary functions, and hepatic telomere length in broiler chicks subjected to hypobaric hypoxia.