| Two experiments were designed in our study. Experiment 1 was conducted to investigate the effects of dietary supplementation with polyunsaturated fatty acids of different vegetable oils and L-carnitine on boar libido, semen characteristics, fatty acid composition of sperm and semen antioxidant properties. Experiment 2 was conducted to investigate the effects of supplementation with different ratio of soybean oil (SO) and flaxseed oil (FO) in the diet on the semen quality, breeding performance and serum reproductive hormone of male SD rats. Experiment 1 Effects of supplementation with different vegetable oils and L-carnitine on the libido, semen characteristics of breeding boars30 adult P×D boars were divided into 3 groups(10 boars each). The diet of treatment 1,2,3 were containing 1.5% SO,1.5% SO+200 ppm carnitine,0.3% SO+1.2% FO+200 ppm carnitine, respectively. The feeding trial lasted 16 weeks. The study was conducted to investigate the effect of dietary supplementation with polyunsaturated fatty acids of different vegetable oils and L-carnitine on boar libido, semen characteristics, fatty acid composition of sperm and semen antioxidant properties. The results showed that:(1) The sperm density and motility of treatment 3 were significantly higher than the treatment 1 (P<0.01), while the sperm density was higher than the treatment 2 (P<0.05).(2) The semen volume and ejaculation duration of treatment 3 were significantly higher than the other groups (P<0.01), and the reaction time was significantly lower than the other groups (P<0.01).(3) During 8-16 weeks, the sperm docosahexaenoic acid (DHA, n-3) and activity of superoxide dismutase (SOD) of treatment 3 were higher than the other groups (P<0.05). The seminal plasma SOD activity of the treatment 1 was significantly lower than the other groups (P<0.01) and the content of malondialdehyde (MDA) was significantly higher than the other groups (P<0.01).Experiment 2 Effects of supplementation with different vegetable oils on reproductive performance and blood biochemical indexes of male SD rats 80 clean male SD rats (weighing 250-290g) were randomly divided into 5 groups (16 rats each). The treatment groups were respectively supplemented with 7% SO (the control group),5.25% SO+1.75% FO,3.50% SO+3.5% FO,1.75% SO+5.25% FO and 7.00% FO. The experiment lasted 60 days. The blood serum on day 0,30,60 were respectively collected by cutting tail way. then using of ELISA method measured serum reproductive hormone (GnRH, LH, FSH, T). Eight male SD rats were choiced from each group to mate with female rats (all were fed the control diet) by 1:1 co-cage breeding on day 60, while another eight male SD rats of each group were sacrificed, to calculate testicular index and sperm characteristics. The results showed that:(1) No significant differences were observed among dietary treatments for testis index (P>0.05), but the control group and 5.25% SO+1.75% FO group had slightly higher than the other groups. Spermatogenesis and spermiogenesis in testes of 5.25% FO group were the best by Electron micrographs of testes sections.(2) Compared with the control group, sperm density and sperm motility of 5.25% FO and 7% FO group were increased (P<0.05) and sperm abnormality rate decreased (P <0.05). Sperm density and sperm motility of 5.25% FO group were higher than the other groups, and the sperm abnormality rate was the lowest.(3) Compared with the control group, with the FO concentration increased, the number and birth weight of male SD rats' offsprings showed an increasing trend. The litter size of 5.25% FO and 7% FO groups were increased by 38%,30%, respectively.(4) Compared with the control group, no significant differences were observed among dietary treatments for serum reproductive hormone (P>0.05) levels on day 0. On day 30 and 60,5.25% FO rats' serum GnRH, LH, FSH and T levels were significantly increased (P<0.05). On day 60,7% FO rats' serum GnRH, LH and T levels were also increased significantly (P<0.05).In conclusions, these results demonstrated that:(1) Dietary supplementation with 0.3%SO+1.2%FO+200 ppm L-carnitine enhanced the boar libido, increased DHA concentration of sperm and semen antioxidant properties, thereby enhancing the boar semen production, sperm motility and sperm density.(2) Dietary supplementation 1.75%SO+5.25%FO could promoted the secretion of the male SD rats'testosterone, thereby enhancing semen quality of the male SD rats, litter size and birth weight of the male SD rats'offspring... |
