Investigation On Placental Efficiency, Litter Traits And Weaning Conflict In Pigs

The reproductive performance of sows is a very important factor influencing the benefit of a pig farm. The screening of sows will be able to provide much help for a pig farm. This experiment is divided into 3 parts with placental efficiency. Aiming to study the influence of placental efficiency on reproductive performance of sows and their offspring production performance. The first part of the experiment as the object of sows, studied the relationship between placental efficiency and reproductive performance of sows. In the second part of experiment as the object of piglets, and study the relation between the content of insulin, growth hormone in cord blood of piglets and the placental efficiency. In the third part on the experiment, studied the effects of placental efficiency with skin injury after live with together.1. The relationship between placental efficiency and reproductive performance of sowsIn this experiment, the purebred Landrace (Landrace 42) sows and purebred large white sows (Yorkshire 36) as the object. Sorted according to the size of placental efficiency, the placental efficiency<3 sows were divided into group 1,3≤placental efficiency≤4.5 sows were divided into second groups, placental efficiency≥4.5 sows were divided into third groups. Analysis the correlation between placental efficiency and reproductive performance of sows. The results showed, litter size and litter size alive are significantly higher than those in large white sows (P<0.05); placental efficiency and litter size, number born alive were strong positive correlation (P<0.05); and the average newborn piglets weight was a strong negative correlation (P<0.05). That placental efficiency can predict the ability of sow breeding, may be an important factor as the sow screening.2. The correlation of the contents of insulin, growth hormone and placental efficiency in cord blood of pigletsIn this experiment, purebred Landrace (Landrace 39) and purebred large white sows (Yorkshire 26) sows offspring as the object of study. According to the placental efficiency size is divided into three groups, analysis of the correlation of the contents of insulin and growth hormone placental efficiency in cord blood of piglets. The results showed, insulin levels decrease with the increase of placental efficiency, and the difference was significant (P<0.05). Placental efficiency and insulin levels had no significant difference, was strongly and positively related to insulin and growth hormone levels (P<0.05). It may be considered the placental efficiency high sow offspring growth performance is lower than the placental efficiency low sow offspring. In our screening sows placental efficiency cannot be neglected in the production performance of piglets.3. The effects of placental efficiency with skin injury after live with together.In this experiment, purebred Landrace (Landrace 30) of sows and piglets and purebred Large White Sows and piglets (Yorkshire30) as the research object. According to the placental efficiency filter out high efficiency in the placenta, placental efficiency, low placental efficiency of 3 groups, the correlation between the score 3h,24h,48h skin injury after weaning gregarious and placental efficiency. The results show the high efficiency of the placenta, groups of piglets scar score was lower (P<0.05), piglets scars of a significant difference in the 3h and 24h, and the 24h is the maximum value. Placental efficiency sows can affect the production performance of piglets.