Effects Of Dietary Sodium Butyrate On Spermatogenesis,Antioxidant Status And Intestinal Function In Roosters

Sodium butyrate(SB)is a sodium salt of a volatile short-chain fatty acid(butyric acid).It has various functions as feed additives.These functions are very useful and make these supplements effective as ingredients in animal feed.It is considered a novel feed additive in poultry production and health.It was hypothesized in this study that butyrate,applied as a feed additive,could enhance intestinal homeostasis and animal health,resulting in improvement reproductive performance in the rooster.However,the effect of sodium butyrate on reproductive performance and testis function remain unknown.For that reason,the aim of the present study was:1.Effects of dietary sodium butyrate on semen quality,and serum oxidative statusin roosters.This study was carried out to evaluate the effects of dietary supplementation sodium butyrate(SB)on semen quality and serum antioxidant capacity of the adult roosters.Three hundred 22-week-old roosters were randomly divided into two dietary treatment groups of 6 pen replicates,namely basal diet(control)and a basal diet containing 0.05%SB.The supplementation of SB was carried out through 33 consecutive weeks(from 22 to 55)weeks of age.During this period,the body weight was measured weekly while semen samples were collected every two weeks.4-time-points from the weeks were chosen for analysis(30,35,45 and 55 weeks of age)respectively.The results showed that SB significantly(P<0.05)improved the semen volume and sperm motility at 30 and 35 weeks of age,while significantly(P<0.05)increased sperm concentration at 30,35 and 45 weeks of age and decreased abnormal sperm percentage during the whole experiment period.Furthermore,the sodium butyrate improved the antioxidant capacity by increasing the antioxidant enzyme activities in serum.CAT activity significantly increased(P<0.05)in birds fed diets supplemented with sodium butyrate at both 30 week and 35 week of age.Moreover birds in butyrate group had higher(P<0.05)serum SOD activity than the control groups at 35 weeks of age.These results indicated that sodium butyrate could enhance semen quality and improved serum antioxidant capacity in roosters,therefore appear as an important feed additive for poultry.2.Dietary sodium butyrate enhanced testosterone synthesis,testicular antioxidant status and semen quality in roosters.To clarify the mechanism outline sodium butyrate improves semen quality in(Chapter 2).The experimental design is same as the previous study.Three-time intervals from the weeks were chosen for analysis(30,35 and 45 weeks of age)respectively.The results showed that SB significantly(P<0.05)increase in the testosterone levels at 30 and 35 weeks of age,while no significant changes were detected in the expression of hydroxysteroid2-beta dehydrogenase 2(Hsd2b2),hydroxysteroid 17-beta dehydrogenase 4(Hsd17b4)and Cytochrome P450 17A1(Cypl7al)which involved in the testicular testosterone synthesis during all ages.The spermatogonial improvement and germ cell layers were increased and further militated against the oxidative stress by significantly(P<0.05)increase the activities of GSH-Px at 30 and 35 weeks of age and SOD at 45 weeks of age in the testis of roosters.In conclusion,the dietary supplementation with SB at the level of 0.05%caused significant improvement about semen traits.Thus,SB can be used as a useful tool for improvement of semen quality in roosters.3.Effects of dietary sodium butyrate on intestinal morphology and antioxidant status in roosters.To clarify effects of dietary sodium butyrate on intestinal function,we determine the intestinal morphology and antioxidant status at 4 time-points(30,35,45 and 55 weeks of age),and further we detect immune parameters and intestinal barrier function related genes at 45 weeks of age in roosters.The experimental design is same as the previous study.The results showed that 0.05%sodium butyrate in the diet maintaining body weight and significantly increased(P<0.05)villus height in jejunum and ileum and villus/crypt ratio of jejunum,while significantly decreased(P<0.05)in crypt depth of ileum at 45 and 55 weeks of age.Furthermore,dietary sodium butyrate improved the antioxidant capacity in the intestinal mucosa,CAT and SOD activities significantly increased(P<0.05)in the jejunum mucosa at 30 weeks of age and increased the concentration of IL-6(in the jejunum and ileum),TNF-?(in the ileum).Moreover,SB significantly up-regulated mRNA expression of mucin(MUC2)in ileum mucosa,while there is no significant increase in occludin,cl.audin-1 and zol mRNA expression in jejunum and ileum intestinal mucosa.Dietary SB significantly decreased the IL-1?(in the serum)these results indicated that sodium butyrate maintains body weight and enhance intestinal barrier functions by improving its morphological development and antioxidant capacity in the intestinal mucosa,regulating the immune response,and up-regulating MUC2 gene expressions in ileum mucosa.Sodium butyrate at level 0.05%had slight effects on the intestinal tight junction in adult breeder roosters.Further studies are needed to investigate the effect of the sodium butyrate and its interactions with other feed ingredients in poultry diets.