Correlation and principal component analysis of semen quality in different stall types of boars

YANG Xiyan; NIE Jingkun; HE Jian; ZHOU Jian; ZHU Xiaoping; ZHAO Yunxiang

Abstract：The study aimed to explore the effects of limited and large pens on the semen quality of adult boars,as well as the relationship between various semen indicators.A total of 50 Duroc boars in limited pens and 220 Duroc boars in large pens were selected as experimental subjects.Semen record data(including 22 semen trait indicators)were collected from a large-scale boar station under a group enterprise in Guangxi from December 2022 to August 2023.By means of analysis of variance,correlation analysis,and principal component analysis,the differences in semen quality among different types of pens were identified,and the relationships between various indicators affecting semen traits were explored.The results demonstrated that the sperm motility and normal morphology of confined boars were significantly lower than those of large pigs(P<0.001),and the semen density was significantly lower than that of large pigs(P<0.05);Compared with the control group,the dynamic parameters of male pig sperm in the restricted range showed no significant difference except for LIN(%)(P>0.05),while other parameters showed extremely significant differences(P<0.001);The proportion of bent tail,curled tail,distal cytoplasmic droplet,proximal cytoplasmic droplet,and midline interruption in the sperm of confined boars was significantly higher than that of large pigs(P<0.001);The sperm abnormalities of confined boars were significantly negatively correlated with VSL,STR,LIN,DSL,and positively correlated with BCF;There is a highly significant positive correlation between the sperm curling tail and the sperm kinematic parameters in the Da Lan boar.The results of principal component analysis showed that the cumulative contribution rates of the first five principal components in the limit bar and the large column were 76.941%and 75.334%,respectively.These findings demonstrate that the overall semen quality of large pen boars was better than that of limited pen boars,and the normal sperm morphology rate,linear velocity of sperm movement,and forward orientation were important indicators for measuring semen quality characteristics.