Abstract
The aims of the current study were to investigate the effect of dietary supplementation of flaxseed powder on some hormonal profile and genomic DNA concentration of Karadi male lambs. Twelve healthy Karadi ram lambs, 6 months old, were randomly divided into 3 equal groups (4 lambs/group); and the treatments were as follow for two months; 0% considered as control group, 4% as a low level (T1), and 8% of flaxseed as a high level (T2) in their feed. Blood samples were collected from each ram lambs every two weeks, serum was separated immediately after sampling, testosterone, estradiol, growth hormone (GH), Thyroid Stimulating Hormone (TSH), and Thyroxine (T4) were measured. Genomic DNA was extracted from each samples. The results showed that testosterone hormone concentration decreased significantly in T2 group (1.575±0.004 n.mol / l) in comparison to control group (6.95±1.992 n.mol / l). Estradiol hormone level significantly increased in T1 (293±4.2 P.mol/l) in comparison to control and T2 (128.5±5.485 and 139±8.083 P.mol/l) respectively. A positive significant effect of flaxseed recorded on growth hormone, which its level increased in T2 group (120±2 ng/ul) in comparison to T1 group (81.5±1 ng/ul). TSH concentration increased significantly in T1 and T2 groups (13.5±2 and 14.5±1 U/ml, respectively) in comparison to control group (7±1.5 U/ml), while T4 hormone was not affected. Flaxseed supplementation caused a significant decrease in Genomic DNA concentration in T2 group (56.2 ng) in comparison to control (28.7 ng). In conclusion, adding flaxseed in lamb rations caused a significant decrease of testosterone, increased estradiol concentration, also each of growth hormone and TSH hormones increased significantly, T4 not affected. This decrease in genomic DNA concentration with flaxseed supplementation may due to one of the mechanisms by which phytoestrogens may influence reproductive physiology that involve in inhibition of enzymes essential for DNA replication.
