The Effect Of Melatonin And Dopamine Hydrochloride On Low Temperature Liquid Storage Of Goats Semen

With the large-scale generalization and application of goats artificial insemination techniques, the need of semen is increased greatly by farming enterprises and farmers. However, these diluent have many problems during semen preservation in low temperature, such as short preservation time, low sperm motility, low conception rate and so on. These problems are seriously restricts the development of goats industry in our country. The further study about goats sperm will be crucial role for accelerate the breeding space and keep excellent goats genes. Therefore, the study of efficient and stable low temperature liquid storage of goats semen is the key problem for this field, the antioxidant and cryoprotectants become the study guide for goats sperm preservation. In order to investigate the effect of melatonin and dopamine hydrochloride on goats semen preservation in low temperature, five different foundation formulas were used for screening the best one, then added different concentrations of melatonin(10, 20, 40, 80 mg/L), dopamine hydrochloride(1, 2, 4, 8 mg/L) and the blank control group, and test semen quality, total antioxidant capacity(T-AOC), malondialdehyde(MDA) concentration, Catalase assay kit(CAT) and Mitochondrial activity, determine the optimal additive amount, study its effect on semen quality during preservation. The following are the main results in this study:1. Among the five low temperature preservation extenders, the extender 3 with glucose 1.15 g,D-fructose 1.45 g, PVA 0.25 g, sodium citrate 1.17 g, EDTA 0.23 g, Na HCO3 0.125 g, penicillin 5000 IU, streptomycin 0.1 g, H2 O 100 m L have a better preservation effect. After five days preservation, the sperm motility rate was 45.42%, the plasma membrane integrity was 47.24%, acrosome integrity was 61.26%(P<0.05). The effective preservation time of extender 3 was 3.2 d, then the extender 2. And the sperm motility, plasma membrane integrity, acrosome integrity ofextender 2were significant lower than the extender 3 in the effective preservation time(P<0.05), but significant higher than the extender 4 and extender 5(P<0.05). The extender 1 was the worst. Therefore, the extender 3 was chosen as the basis in the next stage experiment.2. Added different concentrations melatonin to extender 3, the results showed that with the concentration increasing, the sperm motility rate, plasma membrane integrity, acrosome integrity, mitochondrial activity and T-AOC of each treatment group were increased at first and then decreased, but the MDA content were decreased at first and then increased.When the group added 20 mg/Lmelatonin, after 5 days preservation, the sperm motility rate, plasma membrane integrity, acrosome integrity and mitochondrial activity were49.73%, 49.02%, 67.43% and 49.15% respectively, they were significant higher than other groups(P<0.05). The preservation effect of 40 mg/L melatonintreatment were worse than the groupssupplemented with 20 mg/L at goats semen preservation, but mitochondrial activity, TAOC, MDA contents were not significant(P>0.05). After 5 days preservation, the group added 80 mg/L melatonin preservation effect was worst.This indicated that 20 mg/L melatonin was the best concentration for the low temperature liquid storage of goats semen, the concentration over 40 mg/L was bad for goats semen.3. Added different concentrations dopamine hydrochloride to the extender 3, the results showed that appropriate amount of dopamine hydrochloride was good for low temperature liquid storage of goats semen. 2 mg/L dopamine hydrochloride was the best concentration forgoats semen. After 5 days preservation, the sperm motility rate, plasma membrane integrity, acrosome integrity, mitochondrial activity, T-AOC and CAT were 46.86%, 49.22%, 65.85%, 46.25%, 2.51 IU/m Land 2.82U/m L respectively, they were significant higher than other groups(P<0.05). After 1 day preservation, the sperm motility rate, plasma membrane integrity, acrosome integrity, mitochondrial activity, T-AOC and CAT were decrease significantly when the concentration reach 4 mg/L, After 5 day preservation, they were significant lower than other groups(P<0.05). Therefore, 2 mg/L dopamine hydrochloride was the best concentration for the low temperature liquid storage of goats semen.