Factors Influencing Semen Quality and Fertility in Boars

Abstract

The objectives of this researchwere 1) determine the influence of antibiotics on semen quality, 2) determinethe association among insulin-like growth factor I (IGF-I) in seminal plasma,semen quality, and subsequent fertility, and 3) retrospectively study theassociation among semen parameters and sow fertility. In the first study, the effects of gentamicin (GM), amikacin (AM), neomycin sulfate (NM), and penicillin-streptomycin (PS) in semen extender on the percentagesof motile (MOT), morphologically normal sperm (MOR), and sperm with normalacrosome (NAR) were examined. An in vitro penetration assay was conductedusing sperm cells on day 0 and day 5 of storage. GM and NM groupsshowed higher (p<0.05) MOT than other groups after 5 days of storage. No differences in penetration rate were found among treatments; however,the penetration rate decreased (p<0.05) on day 5 of storage. In the second study, ejaculateswere collected and diluted in an extender (Vital&#8482;). Gilts (n=113)and sows (n=375) were inseminated with the extended semen in homogenetic-homospermic regimens. Farrowing rate (FR), total pigs born (TB) and born alive (TBA) were recorded. IGF-I was determined in seminal plasma by radioimmunoassay. Concentration of IGF-I from 204 ejaculates was 95.38 &#177; 3.56 ng/ml (mean &#177; SEM) and total amount of IGF-I/ejaculate was 23.50 &#177; 1.20 &#956;g. Seminal IGF-I differed (p<0.05) among genetic lines and had no effect (p>0.05)on MOT, MOR and NAR. However, IGF-I was associated (p<0.05) withsemen volume, sperm concentration and total number of sperm/ejaculate. No association between IGF-I level in seminal plasma and fertility indices was found. The third study determinedthe associations among insemination parameters with subsequent fertilityof boar semen using data from the second study. MOR was associated (p<0.05) with fertility parameters. TB and TBA were associatedwith age of semen at the first insemination (SAGE) and number of spermper insemination dose (AIDOSE). With stepwise regression analysis,it was evident that FR was associated with semen volume, MOR and SAGE. Meanwhile, TB and TBA were associated with SAGE, AIDOSE and total numberof spermatozoa/ejaculate. In conclusion, the assessment of semen characteristics may not necessarily delineate fertility between boars.

Description

Keywords

Citation

Degree

PhD

Discipline

Physiology

Collections