Correlation between insulin-like growth factor 1 gene expression and fennel (Foeniculum vulgare) seed powder consumption in muscle of sheep.

It has been shown that addition of fennel in the diets of domestic animals has positive and beneficial effects on growth and meat production traits. Thus, the purpose of current study was to investigate the effect of adding fennel in the ration on growth characteristics and on insulin-like growth factor 1 (IGF1) gene expression in muscle tissue of Kermani lamb. Feeding of animals were performed with three levels of fennel including zero, 10 and 20 g/kg dry matter (DM) for 90 days. After slaughter, small pieces of tissues were removed and rapidly transferred to a nitrogen tank. Then, total RNA extracting and the Real-Time PCR reaction was performed. Results showed that as the level of fennel in the diet increases the amount of IGF1 gene expression also increases significantly in humeral muscle and femur (leg) muscle tissues (p < 0.05). In animals fed with fennel, femur muscle weight, back muscle weight, lean meat weight, final weight, warm carcass weight and live daily gain were greater than in animals fed with diet without fennel (p < 0.05). According to the findings of this investigation, it can be concluded that fennel, by creating positive effects on IGF1 gene expression can be used to improve muscle structure.

Fennel (Foeniculum vulgare) seed powder increases Delta-Like Non-Canonical Notch Ligand 1 gene expression in testis, liver, and humeral muscle tissues of growing lambs.

Delta-Like Non-Canonical Notch Ligand 1 (DLK1) is one of the key genes involved in the development of muscle, liver, pancreas, and lung cells; adipocytes production; and the improvement of digestion, growth performance, and meat quality. It has been documented that fennel is effective on increasing the DLK1 gene (DLK1) expression in the testis, liver, and muscle tissues, which may consequently have important implications for sheep production. Hence, the aim of the current investigation was to evaluate the fennel seed powder's effect on DLK1 expression in testis, liver, and humeral muscle tissues in growing lambs. For the purpose of this study, 30 male Kermani sheep were fed with three different group of diets (number of animals in each group was 10), including control (without any fennel seed powder), treatment 1 (with 10 g/kg of dry matter (DM) fennel seed powder), and treatment 2 (with 20 g/kg of DM fennel seed powder) during a 3-month period. Thereafter, total RNA was extracted, cDNA was synthesized, and Real-Time PCR was performed. The addition of fennel seed powder (in the treatment 1 and treatment 2 groups) in the growing lambs diets consequently resulted in greater expression of DLK1 in both the liver and humeral muscle tissues compared to the testis tissue (P < 0.05). Furthermore, the increased DLK1 expression was higher in the tissue of humeral muscle (P < 0.05) in comparison to the other two tissues. As well, the concentration of blood testosterone was greater (P < 0.05) for the animals fed with fennel powder compared to growing lambs fed with the control diet. However, the concentrations of blood liver enzymes, including serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT), decreased by the addition of 10 g/kg DM fennel to diets of lambs compared to the control diet (no fennel). Therefore, it can be concluded that using fennel seed powder in the diet of growing lamb by affecting the expression of DLK1, can improve the concentrations of blood testosterone, SGOT, SGPT, and muscle structure (increased mass of muscle and size of muscle fiber).