6 Zusammenfassung/Summary .1 Zusammenfassung
6.2 Summary Ellen Schapmann:
Influence of protein source in the diet on sperm parameters in boars
The intent of this study was to answer the question of whether the replacement of fishmeal by vegetable protein affects the quality of sperm, in particular the integrity of sperm membranes in breeding boars. 80 boars of an AI station were divided into two equal groups, one group still received the usual standard feed for boars, while the other group was fed with a fishmeal-containing diet over a period of 12 weeks. In this group the 3%
soybean meal and 5% potato protein in the standard feeding were replaced with 8% fishmeal. 702 ejaculates of 80 boars were examed spermatological over a period of 24 weeks. The examination starts 6 weeks before the feeding trial at intervals of 2 to 4 weeks, the sperm were examined by microscopy and flow cytometry. The focus was on the integrity of plasma- and acrosomemembrane and on the stability of spermchromatin. The fertility results (in terms of pregnancyrates and number of piglets born) of 62 boars (from a total of 13883 inseminations) were evaluated with a special monitoring program of the AI station.
During the examination period, the average daily temperatures and their amplitudes were measured. It should be analyzed if there is a possible link between ambient air temperature and semen quality of the boars.
Statistical analysis was performed using analysis of variance models (SAS program) at a significance level of p <0.05.
The following results were collected and interpreted:
• The spermatological and flowcytometric parameters of both groups of boars were throughout the experimental period at a high level and did not differ significantly from each other.
• The fertility parameters of both groups of boars did not show a significant difference.
• The seasonal effect of temperature induced variations in sperm quality, which were particularly pronounced in animals with reduced sperm quality.
• Statistically significant correlations existed between motility and membrane status (rP = -0.60 at p <0.001), motility and acrosome status (rP = -0.34 at p <0.001), motility and morphologically abnormal spermatozoa (rP = -0.57 at p
<0.001), and membrane status and morphologically abnormal sperm (rP = 0.38 at p <0.001).
• single ejaculates with more than 5% chromatininstable sperm often showed simultaneously other deficites in spermatological parameters. Nevertheless there was no link to reduced fertility.
In conclusion, it was found that the replacement of of fishmeal as the animal protein source with vegetable protein sources (soybean meal and potato protein powder) had no negative impact on the integrity of the sperm membranes or on other parameters of semen quality of boars. It could not be shown if there were feeding-related effects on fertility. The seasonal influence of the warm season had a negative effect on sperm quality. That could be seen particularly strong in animals with reduced sperm quality.
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8 Anhang
8.1 Laborbedarf und verwendete Materialien