Effect Of Energy And Lysine Content Of The Diet On The Reproductive Performance Of Pregnant Sows

This experiment was designed to investigated the effect of energy and lysine content of thediet on maternal body gain, total number born, litter weight, serum biochemical indexes and hormone level, by means of saturation-D best regression design, so as to improve the reproductive performance of primiparous sow and offer theoretical basis for feeding during gestation. In this trial, 36 7~8-month-old B line sows of CRP multiple cross system, weighting 123.26±5.69kg, were randomly allotted to 6 groups of 6 per group and fed individually on diet with six contents of digestible energy and the true digestible lysine. There were two periods in the trial: early gestation and late gestation.The results showed that: (1) As energy content during early gestation and late gestation increased, the maternal body gain increased significantly (p<0.01), and it also had an increasing trend with lysine content increasing. Energy and lysine content during early gestation and late gestation didn't have an effect on total weight of pregnant product, placenta and uterus. (2) Heightening energy content during early gestation, reduced number born alive after 84 days and 112 days (p<0.05), and increased number still born significantly (p<0.01), but higher lysine content can alleviated this negative effect . Increasing energy content also had a positive influence on litter weight after 84 days and 112 days (p<0.05), but when energy content was too high, it turned out to be bad for litter weight. With higher lysine content, litter weight had an increasing trend. (3) Energy and lysine content during early gestation and late gestation didn't have an effect on the content of crude protein in embryo, placenta and uterus. As energy content increased, crude fat in embryo and uterus during early gestation and late gestation also increased, especially crude fat in uterus during late gestation (p<0.05). Energy and lysine content during early gestation and late gestation had no influence on amino acid in embryo. (4) Serum total protein and serum free amino acids of primiparous sow had an increasing trend with lysine content increasing. As lysine content increased, serum urea nitrogen increased firstly but decreased subsequently. (5) During early gestation, the concentration of serum progesterone of sow declined with energy content ascending (p<0.05), but...