摘要
本试验旨在研究标准全消化道可消化钙(STTD Ca)和标准全消化道可消化磷(STTD P)含量对7～25 kg断奶仔猪钙、磷吸收的影响.选取21日龄、体重接近的杜长大杂交断奶仔猪144头,随机分为6组,每组6个重复,每个重复4头猪(阉公猪和母猪各2头).第1～6组饲粮中 STTD Ca 和 STTD P 的比例均为 1.2,STTD P 含量分别为 0.18％、0.26％、0.34％、0.42％、0.50％、0.58％,STTD Ca 含量分别为 0.216％、0.312％、0.408％、0.504％、0.600％、0.696％.试验期42 d.结果表明:1)随着饲粮中STTD Ca和STTD P的含量逐渐升高,血清碱性磷酸酶活性逐渐降低,但组间没有显著差异(P＞0.05),血清降钙素(CT)、甲状腺素(T4)、1,25二羟维生素D3[1,25(OH)D3]、甲状旁腺素(PTH)含量逐渐升高,且6组显著高于1组(P＜0.05).1组血清中钙含量显著低于其他组(P＜0.05),其中2、4和6组的血清钙含量较于其他组更高;1组血清磷含量显著高于5组(P＜0.05).2)饲粮中STTD Ca和STTD P的含量逐渐升高对胃内容物及盲肠内容物pH无显著影响(P＞0.05).3)所有组肠道结构完整,1和2组十二指肠绒毛高度/隐窝深度显著高于5和6组(P＜0.05),2组空肠绒毛高度/隐窝深度显著低于5组(P＜0.05).4)在十二指肠中,2和3组维生素D受体(VDR)的基因相对表达量显著高于1和5组(P＜0.05),1和2组钙磷结合蛋白1(CALB1)的基因相对表达量显著高于4、5和6组(P＜0.05),1组细胞色素P450家族成员24A1(CYP24A1)的基因相对表达量显著高于其他组(P＜0.05);在空肠中,4和6组的钙离子通道6(TRPV6)的基因相对表达量显著高于2和5组(P＜0.05),6组S100钙结合蛋白G(S100G)的基因相对表达量显著高于2组(P＜0.05),4组ATP酶质膜钙离子转运蛋白1(ATP2B1)的基因相对表达量显著高于2组(P＜0.05),5和6组溶质载体家族蛋白34成员A3(SLC34A3)的基因相对表达量显著高于1和2组(P＜0.05),1组CYP24A1的基因相对表达量显著高于其他组(P＜0.05);在回肠中,CYP24A1和SLC34A3的基因相对表达量逐渐降低,1和2组CYP24A1的基因相对表达量显著高于其他组(P＜0.05),2组SLC34A3的基因相对表达量显著高于其他组(P＜0.05);在结肠中,1组TRPV6、ATP2B1和CALB1的基因相对表达量显著高于其他组(P＜0.05).在肾脏中,甲状旁腺素1受体(PTHIR)和钙离子通道5(TRPV5)的基因相对表达量先升高后降低,当升高到NRC(2012)推荐STTD P添加量(STTD P含量为0.34％～0.42％)时到达最大;3和4组PTH1R的基因相对表达量显著高于其他组(P＜0.05),4组TRPV5的基因相对表达量显著高于其他组(P＜0.05).在肝脏中,2组SLC34A3的基因相对表达量显著高于4组(P＜0.05),1组CALB1的基因相对表达量显著高于其他组(P＜0.05).综上所述,饲粮中STTD Ca和STTD P的比例为1.2时,随着饲粮中STTD Ca和STTD P的含量逐渐升高,十二指肠和结肠对钙、磷的吸收能力逐渐减弱,空肠对钙、磷的吸收能力逐渐增强,肝脏对钙、磷吸收能力逐渐降低.当饲粮中STTD Ca和STTD P的含量增加到NRC(2012)推荐的STTD P添加量(饲粮STTD P含量为0.34％～0.42％)时,肾脏对钙、磷重吸收的能力最强.结合血清钙、磷含量数据,当饲粮中STTD Ca和STTD P的含量分别在0.216％～0.312％和0.18％～0.26％时,断奶仔猪能有效利用饲粮钙、磷.
Abstract
The objective of this study was to investigate the effects of standardized total tract digestibility Ca(STTD Ca)and standardized total tract digestibility P(STTD P)contents on calcium and phosphorus absorp-tion in 7 to 25 kg weaned piglets.A total of 144 weaned piglets with a similar body weight at 21 days of age were randomly divided into 6 groups,with 6 replicates in each group and 4 pigs(two castrated boars and two sows)in each replicate.The proportions of STTD Ca and STTD P in the diet were 1.2,and the contents of STTD P were 0.18％,0.26％,0.34％,0.42％,0.50％and 0.58％,respectively,and the contents of STTD Ca were 0.216％,0.312％,0.408％,0.504％,0.600％and 0.696％,respectively.The trial period was 42 days.The results showed as follows:1)with the gradual increase of the contents of STTD Ca and STTD P in the diet,the serum alkaline phosphatase activity gradually decreased,but there was no significant difference be-tween the groups(P＞0.05),and the serum contents of calcitonin(CT),thyroxine(T4),1,25 dihydroxy vi-tamin D3[1,25(OH)D3]and parathyroid hormone(PTH)increased gradually,and group 6 were significant-ly higher than group 1(P＜0.05).The serum calcium content in group 1 was significantly lower than that in other groups(P＜0.05),and the serum calcium content in groups 2,4 and 6 was higher than that in other groups.The serum phosphorus content in group 1 was significantly higher than that in group 5(P＜0.05).2)The contents of STTD Ca and STTD P in the diet increased gradually,and there was no significant effect on the pH of gastric contents and cecal contents(P＞0.05).3)The intestinal structure of all groups was intact,the duodenal villus height/crypt depth in groups 1 and 2 was significantly higher than that in groups 5 and 6(P＜0.05),and the jejunal villus height/crypt depth in group 2 was significantly lower than that in group 5(P＜0.05).4)In the duodenum,the relative expression levels of vitamin D receptor(VDR)gene in groups 2 and 3 were significantly higher than those in groups 1 and 5(P＜0.05),the relative expression levels of calci-um and phosphorus binding protein 1(CALB1)gene in groups 1 and 2 were significantly higher than those in groups 4,5 and 6(P＜0.05),and the relative expression levels of cytochrome P450 family member 24A1(CYP24A1)gene in group 1 were significantly higher than those in other groups(P＜0.05).In the jejunum,the expression levels of calcium channel 6(TRPV6)gene in groups 4 and 6 were significantly higher than those in groups 2 and 5(P＜0.05),the relative expression levels of S100G gene in group 6 was significantly higher than those in group 2(P＜0.05),the relative expression level of ATPase plasma membrane calcium ion transporter 1(ATP2B1)gene in group 4 was significantly higher than that in group 2(P＜0.05),the relative expression levels of A3(SLC34A3)member of solute carrier family protein 34 in groups 5 and 6 that signifi-cantly higher than that in groups 1 and 2(P＜0.05),and the relative expression level of CYP24A1 genes in group 1 was significantly higher than those in other groups(P＜0.05).In the ileum,the relative expression levels of CYP24A1 and SLC34A3 genes decreased gradually,and the relative expression levels of CYP24A1 gene in groups 1 and 2 were significantly higher than those in other groups(P＜0.05),and that of SLC34A3 gene in group 2 was significantly higher than that in other groups(P＜0.05).In the colon,the relative expres-sion levels of TRPV6,ATP2B1 and CALB1 genes in group 1 were significantly higher than those in other groups(P＜0.05).In the kidney,the gene expression levels of parathyroid hormone 1 receptor(PTH1R)and calcium ion channel 5(TRPV5)increased first and then decreased,and reached the maximum when it in-creased to the recommended STTD P addition in NRC(2012)diet(STTD P content was 0.34％to 0.42％).The relative expression level of PTH1R gene in groups 3 was significantly higher than that in the other groups(P＜0.05),and the relative expression of TRPV5 gene in the group 4 was significantly higher than that in the other groups(P＜0.05).In the liver,the relative expression level of SLC34A3 gene in group 2 was significant-ly higher than that in group 4(P＜0.05),and the relative expression level of CALB1 gene in group 1 was sig-nificantly higher than that in other groups(P＜0.05).In summary,when the ratio of STTD Ca and STTD P in the diet is 1.2,with the gradual increase of the contents of STTD Ca and STTD P in the diet,the absorption capacity of calcium and phosphorus in duodenum and colon gradually weaken,the absorption capacity of calci-um and phosphorus in jejunum gradually increase,and the absorption capacity of calcium and phosphorus in the liver gradually decrease.When the contents of STTD Ca and STTD P in the diet increase to the STTD P addi-tion recommended by NRC(2012)(the content of STTD P in the diet is 0.34％to 0.42％),the ability of the kidney to reabsorb calcium and phosphorus is the strongest.Combined with serum calcium and phosphorus da-ta,when the contents of STTD Ca and STTD P in the diet are 0.216％to 0.312％and 0.18％to 0.26％,re-spectively,weaned piglets can effectively use the calcium and phosphorus in the diet.[Chinese Journal of Ani-mal Nutrition,2024,36(7):4243-4257]
基金项目
国家"十四五"重点研发专项(2021YFD1300402)
国家现代农业产业技术体系(CAR-35)
广东省乡村振兴战略专项资金项目(2023TS-3)
科技创新战略专项资金-高水平农科院建设(202106TD)
科技创新战略专项资金-高水平农科院建设(R2023PY-JX014)
维普
万方数据