| 英文摘要
| The objective of this study was to understand the effects of dietary calcium level or Rhizopus fermentation extract (RE) on semen quality of the Muscovy duck.
A total of number 27 28-week old male Muscovy ducks were used in this study and allocated randomly into three groups for different treatments: 3% Ca, 1% Ca and 1% Ca + 0.2% RE. The experiment was divided into two parts. The first part was to investigate the effect of calcium level on the semen quality of Muscovy duck and the second part was to understand the effect of Rhizopus fermentation extract on the semen quality of Muscovy duck. From 30 weeks of age, semen samples were collected twice every week until 52 weeks of age and semen volume, concentration, motility, and total number of spermatozoa were measured. During the experiment, ducks were weighed every four weeks. The blood and semen were also sampled for analysis of blood biochemistry value and sperm morphology. Semen was collected at 38, 46 and 49 weeks of age, and the 108 or 36 female Kaiya ducks at 26 or 36 weeks of age were randomly allocated into three groups for artificial insemination, and the eggs were collected for fertilization observation.
The results indicate that there was no significant difference in body weight gain, semen volume, sperm viability and fertilization rate between the 3% Ca group and the 1% Ca group. The sperm concentration of the 1% Ca group was higher than that of the 3% Ca group at late stage of the study and there was significantly different at 47 weeks of age (Pu003c0.05), but there was no significant difference for the overall sperm concentration. The total number of spermatozoa was higher in the 1% Ca group after 39 weeks of age, but there was no significantly different from 3% Ca group. In sperm motility, the 1% Ca group was significantly higher in straight line velocity (VSL), curvilinear velocity (VCL), and average path velocity (VAP) than the 3% Ca group. In sperm morphology, there was no significant difference in sperm viability, but the high calcium group has a higher sperm necking rate. However, the malformation rate was not significantly different between the two groups.
There was no significant difference in body weight gain, sperm concentration, motility, morphology, viability and fertilization rate between the 1% Ca group and the 1% Ca + 0.2% RE group. In semen volume, 1% Ca + 0.2% RE group was maintained above 1.4 mL, while the 1% Ca group was maintained at 1.2-1.4 mL. However, except for the semen volume of 1% Ca + 0.2% RE group, it was significantly high than that of the 1% Ca group of 47 weeks of age. However, there was no significant difference in other weeks of age between these two groups. In total number of spermatozoa, there was no significant difference between the two groups except at 36 weeks of age the 1% Ca + 0.2% RE group was significantly higher than 1% Ca group.
In conclusion, the dietary calcium level has an adverse effect on sperm motility. The addition of Rhizopus fermentation extract to the dietary does not affect sperm motility, viability, morphology and fertilization rate, but can increase the semen volume in Muscovy duck. Results of this study show that reducing the calcium level in the diet or the addition of the Rhizopus fermentation extract can improve the semen characteristics of the Muscovy duck, which is conducive to the improvement of production efficiency. |
