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本研究旨在通过测定低蛋白质饲粮中植物源血根碱替代色氨酸后仔猪门静脉血浆流率(PVPF)、氨基酸净吸收量及血清尿素氮净吸收量,探讨血根碱替代色氨酸对仔猪PVPF及门静脉氨基酸代谢的影响。试验选取12头20 kg左右的"杜×长×大"三元杂交公猪进行血液插管手术(颈动脉、门静脉和肠系膜静脉插管),随机分为4个处理,每个处理3头猪。4个处理分别为低蛋白质饲粮组(低蛋白质组)、低蛋白质不补充色氨酸饲粮组(缺色氨酸组)、低蛋白质不补充色氨酸添加血根碱饲粮组(血根碱组)和常规饲粮组。结果表明:1)猪PVPF会随着采食时间变化整体呈上升的趋势,在后期趋于稳定,缺色氨酸组6 h内平均PVPF比低蛋白质组、血根碱组和常规饲粮组均低,但差异不显著(P0.05)。2)缺色氨酸组门静脉赖氨酸、色氨酸及精氨酸净吸收量显著低于蛋白质组、血根碱组和常规饲粮组(P0.05),而低蛋白质组、血根碱组和常规饲粮组3组间门静脉赖氨酸、色氨酸及精氨酸净吸收量差异不显著(P0.05)。缺色氨酸组门静脉必需氨基酸及总氨基酸净吸收量显著低于蛋白质组、血根碱组和常规饲粮组(P0.05),而低蛋白质组和血根碱组间门静脉必需氨基酸及总氨基酸净吸收量差异不显著(P0.05)。3)各组的血浆尿素氮的净吸收量相近,差异不显著(P0.05)。由此可见,低蛋白质饲粮中不补充色氨酸,对PVPF和门静脉氨基酸净吸收量有一定影响;在不补充色氨酸添加血根碱后会相对提高PVPF,增加门静脉必需氨基酸和总氨基酸净吸收量,但不影响门静脉血浆尿素氮净吸收量。 相似文献
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《中国畜牧杂志》2019,(3)
本试验旨在研究饲粮外源代谢葡萄糖(MG)水平对断奶仔猪门静脉回流组织(PDV)氨基酸利用量的影响。选择20头健康状况良好、体重在7.74 kg左右的25日龄杜×长×大三元杂交断奶仔猪,分为4个处理组,每组5个重复,给每头猪的门静脉、颈动脉和肠系膜静脉安装血管插管,并安装"T"型回肠瘘管。待仔猪术后恢复正常后,4组分别饲喂MG水平为22.82%、26.59%、36.37%、42.41%的等能、等氮的玉米-豆粕型饲粮,每种饲粮添加0.1%的二氧化钛(TiO2)作外源指示剂。术后3 d,从肠系膜静脉持续灌注对氨基马尿酸(PAH),并从门静脉和颈动脉采血,并且在回肠段收集食糜。结果表明:仔猪PDV氨基酸利用量随着MG水平增加呈先上升后下降的趋势;PDV对17种氨基酸的利用量均在饲粮MG水平为26.59%时达到最大值;必需氨基酸、非必需氨基酸、生糖氨基酸、支链氨基酸也在饲粮MG水平为26.59%时达到最大值(P<0.05)。可见,饲粮适宜MG水平能够显著增加小肠氨基酸消失量和门静脉氨基酸净吸收量,从而显著提高仔猪PDV对饲粮蛋白质的利用效率。 相似文献
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采食不同来源淀粉对生长猪门静脉养分吸收和增重的影响 总被引：3，自引：0，他引：3
研究了不同来源淀粉对生长猪门静脉养分净吸收量和生产性能的影响。结果表明：玉米和糙米组成的试验日粮生长猪生长速度最快，显著快于糯米组（P〈0．05），极显著地快于抗性淀粉组（P〈0．01）。生长猪采食抗性淀粉日粮后，葡萄糖和总氮基酸的门静脉净吸收量分别仅为17．84g／100gFI和5．93g／100gFI，显著低于玉米、糙米和糯米组（P〈0．05）。门静脉净吸收氨基酸模式与回肠末端可消化氮基酸模式有很大区别，肠黏膜代谢对氨基酸模式有选择的修饰作用。生长猪增重速度与门静脉总必需氩基酸净吸收量有比较高的相关关系（P=0．0295）。 相似文献
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酵母培养物和半乳甘露寡糖对育肥猪生长性能的影响 总被引：3，自引：0，他引：3
选择45头体重为(25.3±2.3)kg的杜约二元杂种断奶仔猪,按单因子随机试验设计分为A、B、C3组,A、B组为试验组,C组为对照组,每组15头进行94天的饲养试验。A组饲喂基础饲粮+0.2%酵母培养物+0.05%半乳甘露寡糖;B组饲喂基础饲粮+0.15%酵母培养物+0.08%半乳甘露寡糖;C组饲喂基础饲粮+金霉素80mg/kg,各组基础饲粮完全相同。结果表明,试验全期A、B组日增重较C组分别提高9.0%和6.8%,差异显著(P<0.05);料重比A、B组较C组分别降低10.4%和7.6%,差异显著(P<0.05);A、B组较C组每头多盈利33.46元和20.04元,A组较B组多盈利13.42元。 相似文献
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日粮淀粉来源对生长猪门静脉养分及能量净吸收的影响 总被引：1，自引：1，他引：0
为研究不同淀粉来源对生长猪门静脉养分及能量净吸收量的影响,试验选择杜×长×大三元杂种公猪4头,在门静脉、肠系膜静脉和颈动脉安装插管,进行4×4拉丁方试验.结果表明,试验猪每采食100 g日粮8 h后门静脉净吸收的葡萄糖和氨基酸总量以玉米组最高,分别为27.52和8.89 g,显著高于抗性淀粉组(P＜0.05).抗性淀粉、玉米、糙米和糯米组的门静脉总吸收能量分别为676.61、883.32、806.16和812.43 J,其中以玉米组最高,抗性淀粉组显著低于其他各组(P＜0.05).在门静脉总吸收的能量中,抗性淀粉组以葡萄糖形式吸收的能量显著低于其他各组(P＜0.05);而以VFA形式吸收的能量显著高于其他各组(P＜0.05);4种日粮均为以乳酸形式吸收的能量较低,占吸收总能量的3.22%～5.41%.玉米组门静脉总吸收的能量占摄入总能和消化能的比值分别为51.59%和55.55%,显著高于抗性淀粉组(P＜0.05).由试验结果得出,不同淀粉来源在猪消化道中吸收的形式存在差异,而且提供能量的效率也不相同,主要以葡萄糖形式供能的淀粉源,能量利用效率较高;而主要以VFA或乳酸形式供能的淀粉源,能量利用效率较低. 相似文献
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本试验在分析了22种饲料原料中α-半乳甘露聚糖(α-GM)、β-半乳甘露聚糖(β-GM)和半乳甘露聚糖(GM)含量的基础上,研究了饲粮豆粕水平与β-甘露聚糖酶(β-MN)对断奶仔猪血清α-GM、β-GM、GM含量,血清生化指标,以及肠道溶质载体家族7成员1(SLC7A1)、溶质载体家族7成员11(SLC7A11)、溶质载体家族38成员2(SLC38A2)基因相对表达量的影响。试验采用2×2因子设计,将24头初始体重接近的健康二元杂交断奶仔猪随机分为4组(Ⅰ、Ⅱ、Ⅲ、Ⅳ组),每组6个重复,每个重复1头猪。Ⅰ组饲喂22%豆粕水平饲粮,Ⅱ组饲喂22%豆粕水平并添加0.02%β-MN的饲粮,Ⅲ组饲喂37%豆粕水平饲粮,Ⅳ组饲喂37%豆粕水平并添加0.02%β-MN的饲粮。试验期为30 d。在第30天对24头仔猪进行颈动脉、肠系膜静脉以及肝门静脉采血10 m L,检测血清中α-GM、β-GM和GM含量;对前腔静脉采血10 m L,检测血清生化指标;并取空肠前端和回肠后端,检测SLC7A1、SLC7A11、SLC38A2基因相对表达量。结果表明:与Ⅰ组相比,Ⅲ组断奶仔猪平均日采食量(ADFI)和回肠SLC7A1基因相对表达量均显著降低(P0.05),Ⅲ组断奶仔猪平均日采食α-GM含量,颈动脉血清β-GM含量,肠系膜静脉血清β-GM、GM含量,前腔静脉血清谷丙转氨酶、谷草转氨酶活性和尿素氮含量均显著升高(P0.05);Ⅱ组断奶仔猪肠系膜静脉血清α-GM含量及肝门静脉血清α-GM和GM含量均显著降低(P0.05),前腔静脉血清葡萄糖、钙和高密度脂蛋白含量均显著升高(P0.05)。与Ⅲ组相比,Ⅳ组断奶仔猪肝门静脉血清GM含量显著降低(P0.05),空肠SLC7A1、SLC7A11和SLC38A2基因相对表达量均显著升高(P0.05)。由此可见,仔猪平均日采食α-GM的含量升高,可降低仔猪ADFI;肝门静脉、颈动脉和肠系膜静脉血清α-GM、β-GM和GM含量随饲粮α-GM、β-GM和GM含量的增加而增加。饲粮α-GM、β-GM和GM含量增加时,添加β-MN可降低肝门静脉血清GM含量,上调空肠SLC7A1、SLC7A11和SLC38A2基因相对表达量。 相似文献
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本试验旨在研究长期饲喂高精料饲粮下添加复合缓冲剂(碳酸氢钠20 g/d、氧化镁12 g/d、丁酸钠20 g/d)对奶山羊乳成分、血浆生化指标及激素含量的影响。选择8头安装门静脉及肝静脉瘘管处于泌乳中期的奶山羊随机分为2组,分别饲喂基础饲粮(高精料饲粮组,HG组)和基础饲粮+复合缓冲剂(高精料饲粮+复合缓冲剂组,BG组)。预试期为7 d,正试期为143 d。结果显示:与HG组相比,复合缓冲剂显著升高采食后010 h瘤胃液p H平均值(P0.05);复合缓冲剂显著降低肝静脉血浆中非酯化脂肪酸的含量(P0.05),对门静脉和肝静脉血浆中葡萄糖、β-羟丁酸含量无显著影响(P0.05),对肝脏组织中甘油三酯和总蛋白含量无显著影响(P0.05);复合缓冲剂显著降低门静脉血浆中胰岛素和胰高血糖素的含量(P0.05),对门静脉和肝静脉血浆中胰岛素样生长因子1和生长激素的含量无显著影响(P0.05);复合缓冲剂显著或极显著升高产奶量、乳脂率、乳蛋白率、乳非脂固形物率(P0.05或P0.01)。综合得出,在长期高精料饲粮饲喂条件下,由碳酸氢钠、氧化镁、丁酸钠组成的复合缓冲剂能通过影响奶山羊血浆生化指标及激素含量,影响体机营养物质代谢,最终有效提高产乳量与改善乳品质。 相似文献
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半乳甘露寡糖对早期断奶仔猪生长性能及腹泻的影响研究 总被引：7，自引：0，他引：7
选用体重(8.4±0.27)kg(杜×长×大)28d断奶仔猪72头,随机分为3个处理组,每个处理组6个重复,每个重复4头猪。3组处理日粮分别为:处理1为基础日粮添加0.12%的半乳甘露寡糖;处理2为基础日粮添加50×10-6的金霉素+0.08%的半乳甘露寡糖;处理3为基础日糖添加100×10-6的金霉素。结果表明:处理1的平均日增重和平均日采食量最高,且处理1和2之间差异显著(P<0.05),饲料转化率3个处理组间差异不显著。试验期间,处理2、3组各有1头猪轻微腹泻,注射青链霉素1d后好转,处理1无腹泻发生。试验表明半乳甘露寡糖可提高仔猪生产性能且有减少腹泻发生的趋势。 相似文献
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Four crossbred(Duroc×Landrace×Yorkshire)boars,weighing an average of 22.40 ± 1.08 kg and fitted with permanent catheters in their portal and mesenteric veins as well as their carotid artery,were utilized in a 4 × 4 latin square design experiment in order to investigate the effects of different starch sources(maize,brown rice,sticky rice,and resistant starch)on the absorption of energy sources through the portal vein.Portal blood flow averaged 30.68,28.40,29.99,and 30.12 mL/min per kg BW for pigs fed the maize,brown rice,sticky rice,and resistant starch diets,respectively,and did not differ(P0.05)between treatments.The absorptions of glucose,plasma ammonia,and total amino acids were significantly lower(P0.05)in pigs fed the resistant starch diet than pigs fed the other starch sources.In contrast,significantly(P0.05)higher amounts of propionate and total volatile fatty acids were absorbed from the portal vein of pigs fed resistant starch than pigs fed diets based on maize,brown rice,or sticky rice.In addition,significantly(P0.05)more lactic acid was absorbed from the portal vein by pigs fed the sticky rice diet than pigs fed the other three diets.The energy absorbed from the portal vein in the form of glucose and amino-N as well as the total energy absorbed was significantly(P0.05)lower in pigs fed the resistant starch diet than pigs fed the other three starch sources.In contrast,the amount of energy absorbed in the form of volatile fatty acids was significantly(P0.05)higher in pigs fed resistance starch than pigs fed the other three starch sources.The total energy absorbed through the portal vein as a percentage of the gross energy and digestible energy consumed in pigs fed maize were 50.8% and 54.6%,respectively,which were significantly(P0.05)higher than the values in pigs fed resistant starch(41.5% and 46.6% respectively).The results indicate that energy is absorbed in different forms and with different utilization efficiencies in the digestive tract of pigs as a result of feeding different starch sources.Starch sources supplying most of their energy in the form of glucose had higher energy utilization efficiencies,while starch sources supplying most of their energy in the form of volatile fatty acids or lactic acid had lower energy utilization efficiencies. 相似文献
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Net portal absorption of AA during the 6-h postprandial period was measured in eight gilts (48.5 +/- 1.6 kg BW) in a crossover design. The pigs had chronic catheters placed in the portal vein, carotid artery, and ileal vein, and were trained to consume 1.2 kg of a standard grower diet once daily. Blood samples were taken every 30 min for 4 h and then hourly until 6 h after feeding. The first set of blood samples was taken after pigs were fed a meal of the test 16% CP corn-soybean meal diet (16% CP) or the test 12% CP corn-soybean meal diet supplemented with crystalline lysine, threonine, and tryptophan (12% CP + AA) to equal the three AA levels in the 16% CP diet. Pigs were then fed the standard diet for 2 d. Following that, blood samples were again taken after the pigs were fed a meal of the test diet that was not given to them at the first sampling period. Net portal AA absorption was calculated by multiplying porto-arterial plasma AA concentration difference by portal vein plasma flow rate (PVPF), estimated by an indicator-dilution technique employing p-aminohippuric acid as the indicator infused into the ileal vein. Plasma concentrations of lysine and threonine of pigs were affected by the diet x time interaction (P < 0.01). Portal and arterial plasma lysine and threonine concentrations in pigs attained the maximal level by 1 h postprandial when the 12% CP + AA diet was fed, but reached the peak level at 2.5 h postprandial when the 16% CP diet was given. The PVPF of pigs over the 6 h postprandial was less (P < 0.01) when the 12% CP + AA diet was given than when the 16% CP diet was fed. Net portal absorptions of lysine and threonine also were affected (P < 0.05) by time x diet interaction. The peak portal absorption of both lysine and threonine in pigs appeared at 0.5 h postprandial when the 12% CP + AA diet was given, but at 2.5 h postprandial with the feeding of the 16% CP diet. The early appearance of peak portal absorption of lysine and threonine from feeding the 12% CP + AA compared with the 16% CP diet indicates that crystalline lysine and threonine are absorbed more rapidly than protein-bound lysine and threonine in pigs fed once daily. 相似文献
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Fasting O2 consumption by the whole animal (W) and by portal vein-drained organs (PVDO) during the 24- to 30-h postprandial period were measured in seven growing pigs (36.1 +/- 2.3 kg) with catheters chronically placed in the hepatic portal vein, ileal vein, and carotid artery trained to consume 1.2 kg of a 16% CP corn soybean meal basal diet (B) once daily. The pigs were placed individually into an open-circuit, indirect calorimeter and connected to an arteriovenous (A-V) O2 difference analyzer for hourly simultaneous measurements of O2 consumption by W and PVDO. The PVDO O2 consumption was calculated by multiplying the A-V O2 difference by the portal vein blood flow rate derived from constant infusion of a p-aminohippuric acid solution into the ileal vein. After the initial series of hourly measurements, four pigs remained on the B diet and three pigs were fed a B + 55 ppm carbadox diet. Seven days later, the second series of measurements was made. In pigs fed the diet with carbadox added, the hourly W O2 consumptions were not different (P greater than .05) between the initial and second series and averaged 7.5 mL.min-1.kg of BW-1. However, the A-V O2 differences (mL/dL) were reduced (P less than .05) from 4.6 to 4.0 at 24 h, 4.8 to 4.0 at 25 h, and 4.6 to 4.0 at 29 h postprandial and the fractions of W O2 consumption used by PVDO (percentage) were reduced (P less than .05) from 28.6 to 21.6 at 26 h and 25.2 to 18.2 at 27 h postprandial.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Effect of carbadox on net absorption of ammonia and glucose into hepatic portal vein of growing pigs
Chronic cannulas were placed into the hepatic portal vein, ileal vein and carotid artery of growing pigs trained to consume their daily allowance of 1.2 kg of feed (16% protein corn-soybean meal basal diet) in a single meal. The average preoperative BW of pigs was 44.7 kg for Trial 1 (three pigs) and 35.3 kg for Trial 2 (seven pigs). In Trial 1, net absorption of ammonia (NH3) and glucose into the portal vein was determined three times at weekly intervals. The net portal absorptions were derived by multiplying the porto-arterial plasma concentration difference of NH3 and glucose by portal vein plasma flow rate estimated with the p-aminohippuric acid indicator-dilution technique. Differences in the net portal absorptions of NH3 and glucose among the three weekly measurements were small (P greater than .05). In Trial 2, the first sequence of net portal absorption measurements was conducted when pigs were fed the basal diet, and the second sequence of measurements was conducted after the pigs had been fed the diet supplemented with 55 ppm of carbadox for 7 d. Carbadox supplementation reduced (P less than .05) plasma NH3 concentration in portal plasma during the 2.5-h to 5-h postprandial period and decreased (P less than .05) net portal absorption of NH3 during the 2.5-h to 4-h postprandial period. Carbadox, however, did not affect (P greater than .05) net portal absorption of glucose. We suggest that carbadox suppresses the production of cell-toxic NH3 by intestinal microorganisms and, thus, reduces the injury and turnover of intestinal cells.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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A method for chronically quantifying net absorption of nutrients and gut metabolites into hepatic portal vein in conscious swine 总被引：1，自引：0，他引：1
Surgical procedures are described for chronic cannulation of portal vein, ileal vein, abdominal aorta, and carotid artery in pigs. Silastic or Micro-Renathane tubing was used for cannulating portal vein and ileal vein, while carotid artery was cannulated with Micro-Renathane tubing. The lumen of Micro-Renathane tubing was coated with tri-dodecylmethyl ammonium chloride (TDMAC)-heparin complex. The abdominal aorta was cannulated via saphenous artery with vinyl tubing. This allows simultaneous collection of blood samples from hepatic portal vein and systemic artery (carotid or abdominal aorta) and continuous infusion of p-aminohippuric acid (PAH) into ileal vein. The constant PAH infusion provided an indicator-dilution method for estimating the blood flow rate in portal vein. In 13 pigs weighing 54 +/- 2.8 kg, the mean portal vein blood flow rate during the 8-h postprandial period was estimated to be 1,979 ml X min-1 X pig-1 or 37.8 ml X min-1 X kg-1 body weight. By simultaneously measuring the concentration of nutrients and metabolites in the portal and systemic arterial blood and multiplying porto-arterial differences by the estimated portal vein blood flow rate, the net absorption of nutrients (except long-chain fatty acids) and metabolites into hepatic portal system in conscious swine can be quantified. 相似文献
16.
The aim of the study was to determine if differences in the molecular size of two protein sources affect in vivo intestinal absorption rates of amino acids under normal feeding conditions. Accordingly, the portal absorption rate of amino acids was studied in rats fed semi‐synthetic diets containing native casein (NC) or enzymatically hydrolysed casein as the only protein sources. Enzymatic casein hydrolysate (ECH) consisted of a mixture of free amino acids (51.2% with respect to total amino acids) and low molecular weight peptides. Rats were pre‐adapted to the experimental diets for 5 days prior to the absorption studies. Total free amino acid concentrations in portal vein plasma of rats fed ECH diet at 60, 105, 150 and 195 min after feeding were lower (p < 0.05) than those of rats fed NC. Lower (p < 0.05) concentrations of free threonine, proline, tyrosine, valine and tryptophan at all time points, and higher (p < 0.05) leucine at 60 and 105 min were found in rats fed ECH when compared with those fed NC in portal vein plasma. Portal flow rates of threonine, proline, tyrosine and valine were higher in NC at most time points tested, while leucine and lysine were higher for ECH fed rats 60 and 105 min after feeding. In arterial plasma, significantly (p < 0.05) higher concentrations of some individual free amino acids (proline, tyrosine, valine and tryptophan) were determined at 60, 105, 150 and 195 min after feeding, and lower leucine values after 60 and 105 min, in rats fed NC compared with those fed ECH. Results indicate that in normal feeding conditions amino acids from NC and ECH are absorbed at different rates in rats. 相似文献
17.
本试验旨在研究十二指肠灌注大豆小肽对奶山羊小肠小肽和游离氨基酸吸收的影响。选择7只体况良好、体质量相近的奶山羊((37.88±3.03)kg),安装永久性十二指肠近端瘘管和门静脉、肠系膜静脉近端和远端以及颈动脉慢性血插管进行4×4拉丁方试验,分别从十二指肠灌注生理盐水、60、120、180g.d-1大豆小肽。结果表明,随着十二指肠大豆小肽灌注水平的提高,奶山羊肠系膜排流组织(MDV)总肽结合氨基酸净流量显著增加(P0.05或P0.01);60、120、180g.d-1组门静脉排流组织(PDV)总肽结合氨基酸净流量均显著高于对照组(P0.05),但3个大豆小肽灌注组间无显著性差异(P0.05)。奶山羊小肠对小肽的吸收率随小肠中肽量的增加而下降。随着大豆小肽灌注水平的增加,奶山羊MDV和PDV组织游离氨基酸净流量显著增加(P0.05)。随十二指肠大豆小肽灌注水平的提高,试验羊颈静脉血浆尿素氮浓度显著增加(P0.05),对血浆葡萄糖、胰岛素、生长激素、胰高血糖素和IGF-1浓度没有显著影响(P0.05)。研究结果表明,大豆小肽灌注增加奶山羊小肠中肽结合氨基酸的流量,提高了MDV肽结合氨基酸的净流量,但因肽结合氨基酸吸收率降低或/和肽结合氨基酸吸收细胞降解率提高,降低了进入肠系膜静脉的肽结合氨基酸的比率。 相似文献
18.
Experiments were conducted to determine the effect of the physiological condition of swine on standardized ileal digestibility coefficients (SID). The apparent ileal digestibility coefficients were determined for crude protein and amino acids in six feed ingredients (corn, barley, wheat, soybean meal, canola meal, and meat and bone meal) in growing pigs and in gestating and lactating sows. Growing pigs and lactating sows were given free access to their diets, whereas gestating sows were allowed to consume only 2 kg of feed daily. The nonspecific (basal) endogenous losses of protein and amino acids were determined under similar feeding regimens after feeding a protein-free diet. The SID for crude protein and amino acids were calculated by correcting the apparent ileal digestibility coefficients for the nonspecific endogenous losses of protein and amino acids. With a few exceptions, there were no differences (P > 0.05) in the SID for crude protein and amino acids between growing pigs and lactating sows. Overall, gestating sows had higher (P < 0.05) SID for crude protein and all amino acids, except for tryptophan and aspartate, compared with growing pigs. Likewise, the SID of most amino acids obtained by gestating sows were higher (P < 0.05) than those obtained by lactating sows. Interactions (P < 0.05) between animals and diets were observed for gestating sows compared with growing pigs as well as gestating sows compared with lactating sows. As a consequence, it is not possible to extrapolate data from one feed ingredient to another. On most occasions, the lowest SID among the indispensable amino acids was calculated for threonine, valine, and lysine. It is concluded that gestating sows fed 2 kg of feed per day have higher standardized digestibility coefficients than do growing pigs and lactating sows given free access to their diets. This difference may be due to differences in daily feed intake rather than to the physiological status of the animals. 相似文献