不同比例的羊草纤维素源对五龙鹅消化代谢的影响

选取18月龄的健康五龙鹅24只,随机分为4个组,每组6个重复。各试验组日粮添加的羊草粉含量分别为12.70%、16.70%、21.00%、25.80%,采用全收粪法进行消化代谢试验,检测饲料和粪便中的多种营养成分,确定其消化率。结果表明：在代谢能（ME）和粗蛋白（CP）等摄入量一致的条件下,随着羊草粉添加水平的提高,CF的消化率为13.00%-18.40%,中性洗涤纤维（NDF）14.10%-21.47%,酸性洗涤纤维（ADF）15.40%-22.29%;组间净蛋白利用率（NPU）及氮（N）的沉积量差异不显著（P〉0.05）,粪中氨态氮（NH3-N）浓度显著下降（P〈0.05）,各种氨基酸表观消化率（AAAD）较高（77.30%-91.78%）;P的表观消化率各组间差异不显著（P〉0.05）,而Ca的表观消化率呈递减趋势（P〈0.05）;AKP活性与CF、NDF和ADF的消化率呈显著负相关（P〈0.05）,与Ca、蛋氨酸（Met）、胱氨酸（Cys）消化率呈显著正相关（P〈0.05）;ACP活性与Ca、P表观消化率呈显著正相关（P〈0.05）;其它四种酶的活性与CF、NDF、ADF消化率,Ca、P、Met、Cys表观消化率相关不显著。     

反刍动物日粮中非纤维性碳水化合物营养代谢的研究进展

非纤维性碳水化合物(NFC)是反刍动物日粮中重要的能量组成部分,其在日粮中的含量对反刍动物采食、生产性能、瘤胃发酵、营养物质消化和生理代谢等具有重要影响。本文就NFC对反刍动物采食量和生产性能、瘤胃代谢和营养素利用、机体健康和代谢等方面的影响进行综述,为进一步研究NFC及其科学应用提供参考依据。     

Influence of graded inclusion of white lupin (Lupinus albus) meal on performance,nutrient digestibility and ileal viscosity of laying hens

1. The aim of this study was to investigate the effect of white lupin (Lupinus albus) meal (WLM) addition on the intestinal viscosity, bird performance and nutrient utilisation of laying hens.

2. The experiment was conducted with 360 laying hens aged 21 weeks fed one of 6 treatments, including a corn-soybean meal control diet (CON) and 5 experimental diets containing 60, 120, 180, 240 and 300 g/kg WLM.

3. A linear increase in feed intake (p < 0.001) was observed with higher levels of WLM from 0 to 300 g/kg. Laying rate decreased quadratically (p < 0.05) and egg weight (at 6th, 12th and 18th weeks of the trial) decreased linearly with WLM inclusion from 0 to 300 g/kg. Birds fed 60 g/kg or more of WLM laid lighter eggs (p < 0.05) than CON hens. When 240 g/kg or more WLM was included into the diet, laying rate was affected negatively (p < 0.05).

4. As WLM increased from 0 to 300 g/kg, apparent metabolisable energy and pre-caecal digestibility of dry matter and crude protein decreased quadratically (p < 0.05). When 300 g/kg of WLM was used, there was a tendency (p < 0.1) to decrease pre-caecal starch digestibility. WLM dose exerted a quadratic effect (p < 0.05) on total sialic acid excretion. As WLM increased, the viscosity of ileal digesta linearly increased (p < 0.05).

5. In the 6th and 12th weeks of the experiment (p < 0.05), eggshell thickness decreased linearly when 240 g/kg of WLM was added. At the 6th, 12th and 18th weeks, a linear decrease in eggshell content was observed (p < 0.05) after WLM addition.

6. In conclusion, the graded inclusion of WLM into laying hens’ diets resulted in depressed performance, AME_N and eggshell quality.     

Reduced dietary nitrogen with a high Lys:CP ratio restricted dietary N excretion without negatively affecting weaned piglets

We hypothesized that balancing the content of exogenous amino acids, especially lysine, to reduce protein content in swine diets could reduce nitrogen (N) pollution associated with animal husbandry. Two experiments (45 d each experiment) were performed on weaned piglets (Duroc × Landrace × Yorkshire, 28 d of age) to test this and to determine the optimal lysine to crude protein (Lys:CP) ratio in diet. In Exp. 1, 12 piglets (6 replicates [n = 6]) were fed diets containing different levels of CP (17% and 20%) but the same level of Lys. Increased CP content resulted in significant increases (P < 0.05) of average daily gain (ADG), average daily feed intake (ADFI), and body weight (BW), but did not affect the feed to gain ratio. In Exp. 2, 24 piglets (8 replicates [n = 8]) were fed 1 of 3 diets as follows: 1) 20% CP with a regular Lys:CP ratio (6.23%, control); 2) 17% CP with a reduced Lys:CP ratio (6.14%, LL); or 3) 17% CP with a standard Lys:CP ratio (7.32%, SL). The ADG, final BW, serum concentrations of growth hormone and insulin-like growth factor-1, villus height in the jejunum, and villus height to crypt depth ratio were the lowest in piglets fed LL diet, whereas blood urea N concentration was the lowest and the value of lipase activity was the highest in the piglets fed SL diet. The SL diet did not affect growth performance, intestinal morphology, or serum hormone concentrations, indicating that reduced dietary N with a high Lys:CP ratio can efficiently reduce dietary N excretion without negatively affecting weaned piglets.     

瘤胃素对阿尔巴斯白绒山羊瘤胃发酵及营养物质消化代谢的影响

本论文用1.5岁龄阿尔巴斯型白绒山羊,研究了瘤胃素及瘤胃素+沸石对妊娠母羊瘤胃发酵和营养物质消化代谢的影响。试验结果表明:与对照组相比,添加瘤胃素+沸石提高丙酸占总挥发性脂肪酸(VFA)的比例10个百分点,血液总蛋白含量提高20.94％。同时,补加瘤胃素或瘤胃素+沸石能促进绒山羊对日粮营养物质的利用,日粮干物质消化率分别比对照组提高19.50％、11.87％;日粮有机物质消化率分别提高19.91％、21.83％;日粮粗蛋白质消化率提高10.38％、0.11％;日粮酸性洗涤纤维消化率提高32.75％、17.35％:日粮总能量利用率提高14.93％、6.93％;每日氮沉积量也有显著提高。     

单喂稻草补充非蛋白氮(NPN)对越冬水牛前胃消化代谢的影响

用三头装有瘤胃瘘(其中二头装皱胃瘘)的成年母水牛,冬季舍饲,单喂稻草(Ⅰ期)和补充尿素硫酸铵(Ⅱ期)以及添喂玉米粉(Ⅲ期),研究三种日粮对水牛前胃消化代谢的影响。Ⅱ、Ⅲ期与Ⅰ期比较,有机物(OM)进食量分别提高3％和和21％,酸性洗涤纤维(ADF)消化率都稍有提高,总挥发性脂肪酸(TVFA)、NH_3-N浓度、每天微生物蛋白(MP)合成量和合成效率都有明显增加。Ⅱ、Ⅲ期通过皱胃的总氮(TN)和其中的NAN,MN,NH_3-N的比例也相应增加,尤其通过瘤胃氮(BPN)Ⅲ期增加63.70％。皱胃的氨基酸通过量,Ⅱ期较Ⅰ期有增加趋势,Ⅲ期与Ⅰ期相比,各种氨基酸通过量明显增加,且三期的氨基酸比例较为一致,EAA约占48％,NEAA52％左右。     

The effects of concentrate added to pineapple (<Emphasis Type="Italic">Ananas Comosus linn. Mer.</Emphasis>) waste silage in differing ratios to form complete diets,on digestion,excretion of urinary purine derivatives and blood metabolites in growing,male, Thai swamp buffaloes

Four, male, growing Thai swamp buffaloes (197 ± 5.3 kg and all 1 year old) were used to evaluate the effects of concentrate added to pineapple waste silage in differing ratios, to form a complete diet, studying in vivo digestion, the rate of passage, microbial protein synthesis and blood metabolites. Animals were fed ad libitum with 4 diets, using four combinations of pineapple waste silage (P) and concentrate (C), in the proportions (on a dry matter basis) of 0.8:0.2 (P80:C20), 0.6:0.4 (P60:C40), 0.4:0.6 (P40:C60) and 0.2:0.8 (P20:C80). The results showed that the intakes of dry matter (DM), organic matter (OM), nitrogen (N), the N-balance, urinary purine derivatives (PD) excretion, the ratios of allantoin to creatinine (CR), PD to CR, the plasma urea-N (PUN) and insulin increased in the animals, but the intake of neutral detergent fiber (NDF), the coefficient of whole tract, apparent digestibility of NDF, the transit time (TT) and the mean retention time (TMRT) decreased, when the proportion of concentrate in the diet increased. This study indicated that the proportion of P40:C60 in the diet produced the best efficiency of urinary PD excretion (mmol) per digestible OM intake (kg DOMI).     

Compensatory digestion of fat, protein and starch (rates and amounts) in the large intestine of minipigs in case of reduced precaecal digestion due to pancreatic duct ligation — A short review

To generate quantitative ideas about the digestive capacity of the large intestine of pigs in case of reduced precaecal digestion, the results of several studies using the model “pancreatic duct ligated minipig”, are summarised. Ligation of the pancreatic duct causes an exocrine pancreatic insufficiency (EPI) leading to a severe reduction of precaecal digestibility (prc. dig.) rates [Tabeling, R., Gregory, P. Kamphues, J., 1999. Studies on nutrient digestibilities (pre-caecal and total) in pancreatic duct ligated pigs and the effects of enzyme substitution. J. Anim. Physiol. Anim. Nutr. 82, 251–263.]. All minipigs (control pigs; C and pancreatic duct ligated pigs; PL) were surgically fitted with an ileocaecal re-entrant fistula to determine rates and amounts of precaecal and total tract (total) digestion of crude fat (cfa), crude protein (cp) and starch (st).

The animals were fed diets rich in starch (StD:  60% st in dry matter [DM]) or rich in fat (FaD:  30% cfa in DM). In PL reduced prc. dig. rates, especially of cfa and cp (prc. cfa dig.: C: 88.2–97.6%; PL: 9.3–43.0%; prc. cp dig.: C: 79.1–82.3%; PL: 26.1–40.9%) were found. Digestion of starch was only moderately reduced in PL (prc. st dig.: C: 97.2–99.7%, PL: 61.9–92.5%). Up to 2.6 g of starch and 0.98 g of cp per kg body weight were digested postileally in PL, while postileal cfa digestion was negligible or negative (indicating microbial fat synthesis). Total tract digestibility of st did not differ between C and PL while dig. rate of cp was markedly reduced in PL. The studies permit an evaluation and quantification of the high compensative capacity of the hindgut especially in case of influx of large amounts of starch due to reduced prc. digestibility.     

粗蛋白水平对绵羊日粮养分后肠道消化的影响

本文旨在探讨粗蛋白(CP)水平对绵羊日粮养分后肠道及全消化道消化的影响。试验选4只装有永久性回肠瘘管的4月龄阉羊进行4×4拉丁方试验,定量饲喂4种等能量、相同中性洗涤纤维(NDF)水平、CP水平分别为11.8%(P12组)、14.0%(P14组)、15.9%(P16组)和17.8%(P18组)的日粮。结果表明:随着CP水平提高,日粮DM消化率显著(P<0.05)增加,有机物(OM)消化率无显著变化,CP消化率提高(P<0.01),NDF、酸性洗涤纤维(ADF)、半纤维素(HC)和纤维素(CEL)消化率增加(P<0.01),P12组的各项指标最低。日粮养分后肠道消化占总消化量的比率DM分别为31.3%、29.1%、28.8%和28.6%;OM分别为22.4%、20.8%、20.3%和20.0%;CP分别为19.3%、15.1%、14.3%和13.7%;NDF相应为28.2%、24.7%、23.4%和22.8%;ADF相应为25.3%、21.1%、19.9%和19.4%,P12组日粮ADF后肠道消化比率显著(P<0.05)高于其他3种日粮;HC分别为32.0%、29.5%、27.9%和27.4%;CEL分别为21.1%、18.9%、18.1%和17.9%,P12组日粮CEL后肠道消化比率显著(P<0.05)高于其他3种日粮;淀粉在后肠道消化不到1%。不同的粗蛋白水平对绵羊日粮养分后肠道的消化有一定的影响。     

五龙鹅对黑麦草结构日粮消化代谢规律的研究

选取4.5月龄的五龙鹅32只进行试验,试验分为4个组,1个对照组,3个处理组,每组8个重复,对照组饲喂基础日粮,处理组饲喂基础日粮与青绿冬牧-70黑麦草重量的比例分别为1:2、1:3、1:4(CF占日粮干物质的量分别为9.14％、17.92％、20.40％、22.27％),试验采用全收粪法,连续收集正试期4d排泄物,分析饲料及排泄物中的CF、NDF、ADF、AA、N、Ca、P等的含量。试验结果表明：在能量和CP摄入量一致的条件下,随着日粮粗纤维含量的提高,CF、NDF、ADF消化率逐渐提高;净蛋白利用率处理组间逐渐升高;除蛋氨酸(Met)和胱氨酸(Cys)外,其余氨基酸消化率(AAAD)变化不大;但降低Ca的吸收率,增加P的吸收率。