| The utilization rate,non-productive days,Batch production mode,productive efficiency of female animals can be optimized by using Timed Artificial Insemination procedure,which plays an important role in animal large-scale production.However,there are many challenges in the production and application of domestic gilts,such as the optimization of timed insemination procedure,improvment of the stability and the related molecular mechanism of timed insemination procedure that affecting the reproductive performance of gilts is still unclear.In order to optimize the timed insemination technique,this experiment carried out the effect of the puberty and the different timing infusion techniques on estrus,ovulation,pregnancy and litter giving effects of gilts.Next,transcriptome sequencing technology was employed to detect the expression of related genes in luteum tissue in sows at different stages of pregnancy,and verify the expression patterns of candidate genes in luteum tissue of sows at different stages of pregnancy.In order to investigate the effect of the puberty on the FTAI procedures of gilts,a part of 182 puberty record gilts was randomly allocated to three groups: control group(C1 group,n=62),Altrenogest group(A1 group,n=60)and Altrenogest+PMSG+GnRH group(APG1 group,n= 60).Another part of 193 haven’t puberty record gilts were randomly divided into control group(C2 group,n=63),Altrenogest group(A2 group,n=65)and Altrenogest+ PMSG+ GnRH group(APG2 group,n= 65).The effects of FTAI were assessed by comparing oestrus rate of gilt and pregnancy rate of participating sows among different groups.The results are as follows: The estrus rate of C2,A2 and APG2 in the no puberty group was significantly lower than that in the puberty groups of C1,A1 and APG1(35.48± 3.83% vs.23.81± 3.33%,33.85± 4.58 %vs.63.33± 4.92%,58.46± 3.75% vs.83.33± 3.79%).According to the statistics of pregnancy,the pregnancy rate of no puberty group was only 29.23± 4.36%,after Altrenogest treatment(A2),which was significantly lower than that of puberty group(A1)(53.33± 3.78%),(P<0.05).After treatment with Altrenogest + PMSG + GnRH,the pregnancy rate in the no puberty group(APG2)was also significantly lower than that in the puberty group(APG1)(53.38± 4.82% vs 83.33± 4.26%)(P<0.01).Indicated that the timing of insemination procedure can significantly improve the pregnancy rate of gilts.The puberty period is the key factor affecting the timing of insemination of gilts,and the timed insemination procedures employed in puberty gilts is better.The study on the effects of two kinds of timed insemination procedures showed that the estrus rate of A1,A2,APG1,APG2 groups(63.33± 4.92%,33.85± 4.58%,83.33± 3.79%,58.46± 3.75%)was significantly higher than that of C1 and C2 groups(35.48± 3.83%,23.81± 3.33%)(P<0.05),and the estrus rate of APG1 and APG2 groups was significantly higher than that of A1 and A2 groups(P<0.05),indicated that both timing insemination procedures can significantly improve estrus rate of gilts,but the treatment group of Altrenogest+PMSG+GnRH program was better.The statistical results of pregnancy effects showed that,compared with the control groups C1 and C2(27.42± 3.26%,19.05± 3.76%),the A1 and A2 groups(53.33± 3.78%,29.23± 4.36%)significantly increased the pregnancy rate of the gilts,however,is much lower than that of APG1 and APG2 groups(83.33± 4.26%,55.38± 4.82%),indicated that the estrus rate and pregnancy rate of gilts can significantly improved by the timed insemination procedure,and with the treatment of Altrenogest+PMSG+GnRH procedure is better.The statistical results of estrus concentration showed that the A1 group and the A2 group treated with Altrenogest only concentrated on the 5th to 9th day after stopping the treatment,and there was obvious estrus delay in the A2 group;After treatment with Altrenogest+PMSG+GnRH,both APG1 and APG2 were concentrated on the 5th and 6th day after stopping of Altrenogest.Indicated that Altrenogest+PMSG+GnRH treatment increased the estrus concentration of gilts.The statistical results of litter total number born and litter total number born alive showed that APG1 group(12.98± 1.78%,12.75± 1.61%)and A1 group(12.43± 2.46%,12.03± 2.82%)were significantly higher than C1 group(10.98± 4.52%,10.02± 2.86%)(P<0.05),and APG1 group was higher than A1 group.Indicated that both timed insemination procedures can effectively increase the number of litters,and the Altrenogest+PMSG+GnRH program treatment group is better in increasing litter size.In summary,employed Altrenogest+PMSG+GnRH program is more effective in improving the reproductive performance of gilts.In order to investigate the effects of timed insemination on reproductive related organs and early embryo development in gilts,12 pregnancy gilts were selected from Altrenogest+PMSG+GnRH(test group)and untreated(control group).The animals were slaughtered at 16(16APG)and 25(25APG)days of pregnancy,and the number of luteum in ovarian,the weight of uterine,the length of uterine horn,and embryo diameter were compared,and the ovarian and luteum tissues were analysed by transcriptome sequencing.The results showed that the total weight of ovary,total number of luteum in ovarian and total length of uterine angle of gilts were significantly higher in the experimental group than in the control group(16Cand 25C)(P<0.01),and the left and right ovary weights were not significantly different between the groups in each group(P>0.05).But the left and right number of luteum in ovarian and uterine horn length were significantly different between the experimental group and the control group(P<0.05),meanwhile the uterus weight of the experimental group was significantly higher than that of the control group at 25 days of pregnancy(P<0.01).The results of embryo diameter measurement showed that the length of embryos in the 16-day pregnancy group was not significantly different from that in the control group(P>0.05),but the experiment group was significantly larger than the control group at 25 days of pregnancy(P<0.05).The transcriptome sequencing of luteum tissues in different pregnancy stages of gilts employed by timed insemination procedure showed that 30143 genes were differentially expressed in different stages of pregnancy and different treatment groups(P<0.05,difference multiples>0.0).By clustering,GO and KEGG analysis,the number of differential genes between 16 APG group and 16 C group was much larger than that between 25 APG group and 25 C group(2394vs.1476).The number of differential genes between 16 APG group and 25 APG group was close to that of 16 C group and 25 C group(1211vs.1060).Indicated that the genetic differences caused by the number of days of pregnancy was close to that of the 25 th day of pregnancy and the 16 th day of pregnancy,suggesting that the timing of insemination procedure is the main factor causing the difference in the genetic changes of the gilts in different stages of pregnancy,and the difference in expression of ovarian and luteum tissues during pregnancy mainly occurs in the early stage of attachment.Differentially expressed genes were screened by GO analysis,cluster analysis and KEGG analysis: CYP17A1、IL18、LDLR、DCN、RPL10 and PRLR.The expression of these differentially expressed genes in the luteal tissue were verified bu qPCR,and the results showed that RPL10、CYP17A1、DCN、IL18 and LDLR in the timed insemination group were significantly higher than that in the control group(P<0.05).The expression of PRLR in the timed insemination group was significantly lower than that in the control group(P<0.01).In summary,the timed insemination should try to choose gilts with puberty;Altrenogest+PMSG+GnRH program can significantly improve the reproductive efficiency of gilts.The expression levels of CYP17A1,LDLR,IL18,DCN and RPL10 are increased,and the decrease of PRLR expression is likely to be an important reason for the improvement of reproductive efficiency of gilts in sows with Altrenogest+PMSG+GnRH program. |
PDF Full Text Request