Investigation Of The Reproductive Performance On Scale Pig Farms In Jiang Su

Pig farm production efficiency is mainly affected by the sow productivity.And sow productivity levels has two major parts:litter performance including litter size,number of piglets born alive,piglet birth weight and reproductive performance including weaning mating interval,production cycle which are supplement each other,and restrict each other.I Two medium-sized farms were selected to exploring the main factors affected the level of sow reproductivity and investigation of production levels of breeding sows.In the field study records of breeding sows of two pig farms were collected the records of the original breed farm from 2011 to 2014 and the Yorkshire × Landrace sow herd from 2010 to 2014.After an analysis of the statistical data,the following results are obtained:In the original breed farm,the reproductive performance of average litter size,number of piglets born alive and number of piglets weaned were 11.15±3.19,10.51±3.05,9.80±2.25 respectively.The average farrow-to-farrow interval(days)was 159.30±8.80.And we found that:(1)The average litter size of the Large white,Landrace are significantly(p<0.05)higher than that of Duroc.(2)2 to 5 tire swine reproductive performance is superior to the other tires.(3)As a result of the influence of heat stress,weaning mating interval of June-August sows is longer than other months.(4)It is helpful to improve the litter size at the age distribution of 260-289 days of the sows in the mating for the first time.In the Yorkshire×xLandrace sow herd:the reproductive performance of average litter size,number of piglets born alive and number of piglets weaned were 11.67±2.67,11.12±2.61,10.32±1.87 respectively.The average farrow-to-farrow interval(days)was 159.46±9.23.And we found that:(1)The best breeding tires times is 3-6 of the Large white,Landrace.(2)It is helpful to improve the litter size at the age distribution of 260-289 days of the the Large white,Landrace sows in the first mating time.(3)It is beneficial to improve the next litter performance to breeding after 4-6 days of weaning.Through the investigation and analysis about sows eliminated in June 2011-13 in June 2013 have found that most of sows were eliminated due to the persistent diestrous and unpregnant for manytimes.The ratio of Follicular cyst sows which are Persistent diestrous ones have reached 54.55%,and the proportion of sows got lutein-cyst in unpregnant groups have reached 27.27%.The concentration of estrogen in blood are much higher in unpregnant sows than it was in persistent diestrous ones.Through the above analysis,the litter performance of the original breeding pig farm and the Yorkshire×Landrace sow herd is higher,the long non-production days and high number of deformity piglet are the main factor restricting the two pig fertility rise;Ovarian cysts may delayed sows’ estrus,and the high estrogen level may lead to the sows’unpregnant.Strengthen management of sows and piglets feeding,shorten the non-production period will improve sow productivity will make the enterprise gain greater production efficiency.