The Effect of Ginger on Frozen-Thawed Sperm Quality and Fertility of Broiler Breeder Roosters

Introduction: Fertility is one of the main factors influencing the economic result in poultry flocks and it is influenced by several variables including breed, nutrition quality, flock age and sperm quality. As a result, the decrease in the fertility of beef mother herds after the peak of production is one of the most important factors in reducing the economic profit of breeding units. It has been shown that fertility decline at the end of the productive period can be partially prevented through artificial insemination. The requirement for optimal use of artificial insemination in any species is the possibility of storing sperm in liquid and frozen form. Fertility rate of poultry sperm in frozen conditions is facing a serious challenge compared to other species, this challenge may be related to some special physiological characteristics of rooster sperm that lead to increased sensitivity in frozen conditions. Ginger is a plant that has strong antioxidant substances, which increases the level of antioxidant enzymes and collects free radicals and protects the cell membrane against the risk of oxidation and peroxidation of fats. The main antioxidant compounds in ginger are gingerols, sesquiterpenes, shogaols and some phenolic ketone derivatives, which have the ability to neutralize superoxide and hydroxyl radicals. This evidence shows that adding ginger powder to the diet of broilers can improve the quality of sperm after thawing and increase the fertility rate by improving the antioxidant properties of semen and protecting sperm from damage caused by freezing-thawing.Materials and Methods: In this research, twenty-seven Ras 308 breeding broilers were tested in the southern desert research farm in collaboration with Khuzestan University of Agricultural Sciences and Natural Resources.  At the age of 47 weeks, the sows were habituated for two weeks in individual cages and fed with basic ration and abdominal rubbing method for sperm collection. From the age of 49 to 60 weeks for 12 weeks, the sows were fed with a basic diet (control group) or diets with different levels of ginger powder (treatment groups) and kept at a temperature of 19-23 degrees Celsius and a photoperiod of 14 hours of light and 10 hours of darkness.  Experimental treatments included: control diet (no feeding of ginger powder), daily feeding of 7.5 grams of ginger powder and daily feeding of 15 g of ginger powder per kg of diet. During the test period, sperm samples were collected weekly by abdominal rub method and after initial evaluation, from the age of 51 weeks, they were frozen, and the quality parameters of semen, including total and progressive aspect, plasma membrane function, sperm viability and morphology after thawing were evaluated. took Frozen semen samples from weeks 59 and 60 were inoculated into broiler hens to evaluate sperm fertility after thawing.Results and Discussion: The effect of treatment and test weeks on most of the parameters measured including total and progressive motility, viability and function of sperm plasma membrane was significant. The interaction of treatment and test weeks significantly affected overall and progressive behavior, but its effect on survival tended to be significant. The effects of treatment, week and the interaction of treatment in week had no significant effect on the percentage of abnormal sperms. The study by Shafiq et al. (2015) improved the storage of rooster sperm using rosemary essential oil after the freezing and thawing process; The results of the research showed that the use of rosemary essential oil in the diluent improves the quality of rooster sperm, which is consistent with the present research.  Ginger comprises essential antioxidant compounds such as gingerols, sesquiterpenes, shogaols, and certain phenolic ketone derivatives. These compounds possess the remarkable ability to neutralize superoxide and hydroxyl radicals, contributing to their sustained antioxidant activity. Furthermore, the antioxidant enzyme glutathione peroxidase plays a crucial role in safeguarding sperm in the tissues of the testis and epididymis. A decline in the levels of this enzyme within the body has been associated with infertility. Recognizing the significance of these antioxidant components and enzymes underscores their continuous impact on maintaining reproductive health. By being placed in the sperm plasma membrane, this enzyme protects the sperm nucleus and epididymal fluid from the attack of free radicals and causes the final swelling and development of sperms. Fertility percentage and sperm yield in chicks of hens fed with 7.5 and 15 g/kg of ginger powder in the diet increased significantly compared to the control group. Among the sperm parameters, sperm motility and viability are considered to be the most important factors influencing sperm transfer to SSTs; In this research, the total and progressive motility and survival were increased in the groups of 7.5 and 15 grams per kg of diet, which can be the reasons for increasing the fertility and hatching of chicks in these groups. In a research by Masoudi et al. (2021), they investigated the effect of milk thistle, carob and ginger on the reproductive performance of Ras breed broilers and reported that supplementing the diet with plant additives significantly improved the quality of sperm and fertility of the sows compared to the control group.Conclusion: In generally, the results of the present study showed that the addition of 7.5 and 15 g per kg of ginger powder in the diet significantly increased the total and progressive motility, the integrity and function of the plasma membrane, and finally, the fertility and egg retrieval of sperm after thawing.