Effects Of Different Delivery Seasons And Parities On Reproductive Performance Of Yorkshire Sows

In order to study the effects of different delivery seasons and parities on reproductive performance of Yorkshire A,B,and E,the reproductive records of delivery sows were collected in Shanghai a pig farm from 2013 to 2017,and the number of litters of different delivery seasons and parities of Yorkshire sows were analyzed by SPSS software to find the differences between the number of litters,so that we can provide certarn reference for improving the reproductive performance of Yorkshire sows.The results were showed:1?According to different delivery seasons,in 2013,it was found that total born per farrow and live bom per farrow of Yorkshire sows A were the highest in spring,which was significantly higher than in summer,autumn and winter(P<0.05);the total born per farrow and live born per farrow of Yorkshire sows B were no significant difference for between different seasons(P>0.05);the total born per farrow and live born per farrow of Yorkshire sows E were the highest in spring.In 2014,the total born per farrow and live born per farrow of Yorkshire sows A of the spring were significantly higher than in summer,autumn and winter(P<0.05);the total bon per farrow and live bom per farrow of Yorkshire sows B were the highest in spring;the total born per farrow and live born per farrow of Yorkshire sows E were no significant difference between various seasons(P>0.05).In 2015,total born per farrow of Yorkshire sows A was the highest in summer,and its live born per farrow was the highest in winter;the total bon per farrow of Yorkshire sows B was the highest in spring,and its live born per farrow was the highest in winter;the total born per farrow and live bom per farrow of Yorkshire sows E was the highest in spring.In 2016,the total bom per farrow and live bom per farrow of Yorkshire sows A,B,and E were the highest in spring.In 2017,the total bom per farrow of Yorkshire sows A was the highest in summer,and the live born per farrow of Yorkshire sows A was the highest in spring;the total bom per farrow and live born per farrow of Yorkshire sows B and E were no significant difference between each seasons(P>0.05).2?The results were analyzed according to different Parities,it was found that total born per farrow and live born per farrow of Yorkshire sows A of the 1st parity were the lowest,and 3rd parity were hightest in 2013;the born per farrow of Yorkshire sows B of the 3rd parity was the hightest,and its live bon per farrow of 2nd parity was the hightest;the total born per farrow and live born per farrow of Yorkshire sows E of 3rd parity were the hightest.In 2014,the total born per farrow and live born per farrow of Yorkshire sows A,B,and E of 3rd parity were the highest.In 2015,total born per farrow and live bom per farrow of Yorkshire sows A of the forth parity were the hightest;the total bon per farrow and live born per farrow of Yorkshire sows B and E of 3rd parity were the hightest.In 2016,the total bom per farrow and live bom per farrow of Yorkshire sows A of 3rd parity were the hightest;the total born per farrow and live born per farrow of Yorkshire sows B of forth parity were the hightest;the born per farrow of Yorkshire sows E of the fifth parity was the hightest,and its live bom per farrow of forth parity was the hightest.In 2017,the total born per farrow and live born per farrow of Yorkshire sows A of the forth parity were hightest;the total born per farrow and live bom per farrow of Yorkshire sows B of the sixth parity were hightest;the total bon per farrow and live born per farrow of Yorkshire sows E were no significantly difference between each parities(P>0.05).3?The effects of different years,strains,parities and seasons on reproductive performance of Yorkshire sows were analyzed by mixed linear model.The results showed that years*seasons had significant interaction among total number of piglet per farrow,number of live piglet per farrow,number of male piglet per farrow,number of female piglet per farrow and number of healthy piglet per farrow of Yorkshire sows(P<0.01),and year*strain*season only had significant interaction among the number of male size of Yorkshire sows(P<0.05).All in all,spring is the best delivery season for Yorkshire sows A,B,and E,and the 3rd to fifth parity are the best reproductive performance.