Background: A 21-day experiment was conducted to test the hypothesis that Ca requirements to maximize growth performance expressed as the standardized total tract digestible(STTD) Ca to STTD P ratio is less than 1.40:...Background: A 21-day experiment was conducted to test the hypothesis that Ca requirements to maximize growth performance expressed as the standardized total tract digestible(STTD) Ca to STTD P ratio is less than 1.40:1. The second hypothesis was that increasing dietary Ca increases plasma Ca concentration and downregulates abundance of genes related to Ca absorption(TRPV6, S100 G, and ATP2 B1) in the duodenum, and tight junction proteins(OCLN, CLDN1, and ZO1) in the duodenum and ileum.Methods: Twenty corn-soybean meal diets were formulated using a 4 × 5 factorial design with diets containing 0.16%, 0.33%, 0.42%, or 0.50% STTD P, and 0.14%, 0.29%, 0.44%, 0.59%, or 0.74% STTD Ca. Six hundred and forty pigs(initial weight: 11.1 ± 1.4 kg) were allotted to 20 diets and 5 blocks in a randomized complete block design. On day21, weights of pigs and feed left in feeders were recorded and blood, duodenal tissue, ileal mucosa, and the right femur were collected from 1 pig per pen. Abundance of m RNA was determined in duodenal and ileal tissue via quantitative RT-PCR. Data were analyzed using a response surface model.Results: The predicted maximum ADG(614 g), G:F(0.65), and bone ash(11.68 g) was obtained at STTD Ca:STTD P ratios of 1.39:1, 1.25:1, and 1.66:1, respectively, when STTD P was provided at the requirement(0.33%). If dietary STTD P was below the requirement, increasing dietary Ca resulted in reduced(P < 0.05) ADG and G:F. However, if dietary STTD P was above the requirement, negative effects(P < 0.05) on ADG and G:F of increasing STTD Ca were observed only if dietary STTD Ca exceeded 0.6%. Plasma Ca concentration was positively affected by STTD Ca over the range studied(quadratic, P < 0.01) and negatively affected by increasing STTD P(linear, P < 0.01). There was a linear negative effect(P < 0.05) of STTD Ca on the abundance of S100 G, TRPV6, OCLN, and ZO1 in duodenum, and CLDN and ZO1 in ileum.Conclusions: The STTD Ca:STTD P ratio needed to maximize growth performance of 11-to 25-kg pigs is less than1.40:1, if P is at the estimated requirement. Increasing dietary Ca reduces transcellular absorption of Ca and increases paracellular absorption of Ca.展开更多
基于比较基因组学方法,选择大白猪和梅山猪作为试验材料,根据人、小鼠和猪的BM P 15基因设计并合成4对引物,进行基因组DNA的PCR扩增、克隆、测序,用BLA ST软件进行DNA序列排列,获得包含猪BM P 15基因外显子1(exon1)和外显子2(exon2)的...基于比较基因组学方法,选择大白猪和梅山猪作为试验材料,根据人、小鼠和猪的BM P 15基因设计并合成4对引物,进行基因组DNA的PCR扩增、克隆、测序,用BLA ST软件进行DNA序列排列,获得包含猪BM P 15基因外显子1(exon1)和外显子2(exon2)的全部编码区序列。用Pa irw ise BLA ST软件,将大白猪、梅山猪BM P 1 5基因编码区序列进行比较,在外显子2区域发现了一个SNP位点,位于编码区第390个核苷酸处,大白猪为T,梅山猪为A,且该位点导致了限制性内切酶Sp eⅠ酶切位点发生了改变。建立了猪BM P 15基因基于内切酶Sp eⅠ的PCR-RFLP多态性检测技术,发现猪BM P 15基因有3种基因型(BM P 15AA、BM P 15AB、BM P 15BB)。展开更多
基金Financial support for this research from AB Vista,Marlborough,UK
文摘Background: A 21-day experiment was conducted to test the hypothesis that Ca requirements to maximize growth performance expressed as the standardized total tract digestible(STTD) Ca to STTD P ratio is less than 1.40:1. The second hypothesis was that increasing dietary Ca increases plasma Ca concentration and downregulates abundance of genes related to Ca absorption(TRPV6, S100 G, and ATP2 B1) in the duodenum, and tight junction proteins(OCLN, CLDN1, and ZO1) in the duodenum and ileum.Methods: Twenty corn-soybean meal diets were formulated using a 4 × 5 factorial design with diets containing 0.16%, 0.33%, 0.42%, or 0.50% STTD P, and 0.14%, 0.29%, 0.44%, 0.59%, or 0.74% STTD Ca. Six hundred and forty pigs(initial weight: 11.1 ± 1.4 kg) were allotted to 20 diets and 5 blocks in a randomized complete block design. On day21, weights of pigs and feed left in feeders were recorded and blood, duodenal tissue, ileal mucosa, and the right femur were collected from 1 pig per pen. Abundance of m RNA was determined in duodenal and ileal tissue via quantitative RT-PCR. Data were analyzed using a response surface model.Results: The predicted maximum ADG(614 g), G:F(0.65), and bone ash(11.68 g) was obtained at STTD Ca:STTD P ratios of 1.39:1, 1.25:1, and 1.66:1, respectively, when STTD P was provided at the requirement(0.33%). If dietary STTD P was below the requirement, increasing dietary Ca resulted in reduced(P < 0.05) ADG and G:F. However, if dietary STTD P was above the requirement, negative effects(P < 0.05) on ADG and G:F of increasing STTD Ca were observed only if dietary STTD Ca exceeded 0.6%. Plasma Ca concentration was positively affected by STTD Ca over the range studied(quadratic, P < 0.01) and negatively affected by increasing STTD P(linear, P < 0.01). There was a linear negative effect(P < 0.05) of STTD Ca on the abundance of S100 G, TRPV6, OCLN, and ZO1 in duodenum, and CLDN and ZO1 in ileum.Conclusions: The STTD Ca:STTD P ratio needed to maximize growth performance of 11-to 25-kg pigs is less than1.40:1, if P is at the estimated requirement. Increasing dietary Ca reduces transcellular absorption of Ca and increases paracellular absorption of Ca.
文摘基于比较基因组学方法,选择大白猪和梅山猪作为试验材料,根据人、小鼠和猪的BM P 15基因设计并合成4对引物,进行基因组DNA的PCR扩增、克隆、测序,用BLA ST软件进行DNA序列排列,获得包含猪BM P 15基因外显子1(exon1)和外显子2(exon2)的全部编码区序列。用Pa irw ise BLA ST软件,将大白猪、梅山猪BM P 1 5基因编码区序列进行比较,在外显子2区域发现了一个SNP位点,位于编码区第390个核苷酸处,大白猪为T,梅山猪为A,且该位点导致了限制性内切酶Sp eⅠ酶切位点发生了改变。建立了猪BM P 15基因基于内切酶Sp eⅠ的PCR-RFLP多态性检测技术,发现猪BM P 15基因有3种基因型(BM P 15AA、BM P 15AB、BM P 15BB)。
