L-carnitine-induced changes in the expression profile of key genes in broiler chickens of the “Smena 9” cross, taking into account sex differences

Relevance. The study of the effect of L-carnitine on the productivity and gene expression of broiler chickens, taking into account sex differences, is relevant for optimizing feeding and increasing production efficiency.

The aim of the study was to study the effect of L-carnitine in various dosages on the expression of key genes in broiler chickens of the “Smena 9” cross.

Methods. Groups were formed: I (control) received the basic ration (RR), II (experimental) — RR + L-carnitine at a dosage of 30 g/t of feed, III (experimental) — RR + L-carnitine at a dosage of 60 g/t of feed, IV (experimental) — RR + L-carnitine in a dosage of 90 g / ton of feed.

Results. The addition of 60–90 g/t of L-carnitine to the feed (experimental groups III and IV) increased the live weight gain of roosters (by 115 g and 119 g, respectively) compared with the control group (I) (p < 0.05). Similar data was obtained for chickens. In the cockerels in group III, the expression of AvBD9 was increased by 54.4 times (p < 0.05) compared with the control, and in group IV, the expression of AvBD10 increased by 10.3 times (p < 0.05). In chickens, L-carnitine inhibited the expression of AvBD9 (a decrease of 7 times for group II, p < 0.05) and AvBD10 (a decrease of 5.7 times for group II, p < 0.05). The expression of IL6 increased (2.3-fold in group III and 1.9-fold in group IV, p < 0.05) and IL8L2 (maximum 3.3- fold in group II, p < 0.05). L-carnitine has a complex effect on molecular processes in the blind processes, however, these effects may differ depending on the sex of the bird.

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