生产层不同测定方法对青贮饲料中NDF和ADF含量的影响

为探讨滤器和不同测定方法对青贮饲料中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）的影响,本试验选取内蒙古地区常见的8种青贮饲料为供试材料,选用ANKOM滤袋、CAU滤袋和P2型玻璃坩埚为热抽滤装置,以传统的范氏法为对照,分别对青贮饲料NDF的测定进行耐高温α 淀粉酶处理, ADF的测定采用连续洗涤法。结果表明,8种青贮饲料的NDF和ADF含量,经ANKOM滤袋和CAU滤袋所测结果均无显著差异;通过P2型玻璃坩埚测定的NDF值普遍高于其他2种滤器测得结果,尤其以TMR青贮饲料最为显著;经P2型玻璃坩埚测得全株玉米（Zea mays）青贮和TMR青贮饲料的ADF含量显著（P＜0.05）高于其他2种滤器的测得结果;与对照相比,通过在中性洗涤剂中添加耐高温α 淀粉酶,全株玉米青贮饲料和TMR青贮饲料NDF值显著下降,其他青贮饲料NDF值无显著（P>0.05）变化;连续洗涤法对苜蓿(Medicago stiva)青贮饲料和尖叶胡枝子(Lespedeza hedysaroides)青贮饲料的ADF产生显著（P＜0.05）影响,对其他青贮饲料ADF无影响。     

Effects of ruminal casein and glucose on forage digestion and urea kinetics in beef cattle

Effects of supplemental glucose and degradable intake protein on nutrient digestion and urea kinetics in steers (Bos taurus) given ad libitum access to prairie hay (4.7% CP) were quantified. Six ruminally and duodenally cannulated steers (initial BW 391 kg) were used in a 4 × 4 Latin square with 2 extra steers. Treatments were arranged as a 2 × 2 factorial and included 0 or 1.2 kg of glucose and 240 or 480 g of casein dosed ruminally once daily. Each period included 9 d for adaptation, 4 d for total fecal and urine collections, and 1 d for ruminal and duodenal sampling. Jugular infusion of (15)N(15)N-urea with measurement of enrichment in urine was used to measure urea kinetics. Glucose reduced forage intake by 18% (P < 0.01), but casein did not affect forage intake (P = 0.69). Glucose depressed (P < 0.01) total tract NDF digestion. Glucose supplementation decreased ruminal pH 2 h after dosing, but the effect was negligible by 6 h (treatment × time; P = 0.01). Providing additional casein increased the ruminal concentration of NH(3), but the increase was less when glucose was supplemented (casein × glucose; P < 0.01). Plasma urea-N was increased (P < 0.01) by additional casein but was reduced (P < 0.01) by glucose. Microbial N flow to the duodenum and retained N increased (P ≤ 0.01) as casein increased, but neither was affected by glucose supplementation. Urea-N entry rate increased (P = 0.03) 50% with increasing casein. Urinary urea-N excretion increased (P < 0.01) as casein increased. The proportion of urea production that was recycled to the gut decreased (P < 0.01) as casein increased. Glucose supplementation decreased (P < 0.01) urinary urea excretion but did not change (P ≥ 0.70) urea production or recycling. The amount of urea-N transferred to the gut and captured by ruminal microbes was less for steers receiving 480 g/d casein with no glucose than for the other 3 treatments (casein × glucose interaction, P = 0.05), which can be attributed to an excess of ruminally available N provided directly to the microbes from the supplement. Overall, the provision of supplemental glucose decreased forage intake and digestibility. Increasing supplemental casein from 240 to 480 g/d increased urea production but decreased the proportion of urea-N recycled to the gut.     

纤维消化动力学研究进展

消化动力学是动物营养研究中的重要领域,因为动物营养研究的主要目的就是如何解决饲料的消化吸收与转化的问题。目前对于消化动力学的研究主要集中在对于动力学测定指标、动力学影响因素方面的研究。着重阐述纤维定义及作用,消化动力学测定指标,影响纤维消化动力学因素等方面的内容,为纤维的消化机理研究提供参考。     

药用植物提取物对绵羊采食量、养分消化及瘤胃发酵性能的影响

文章旨在探讨日粮添加不同水平药用植物提取物对绵羊采食量、采食行为、养分消化及瘤胃发酵性能的影响.试验将60头平均体重为82.76 kg的绵羊随机分为3组,每组5个重复,每个重复4头.3组绵羊在10?w的试验期中分别饲喂基础日粮+0、80和160?mg/kg药物复合植物提取物.结果:80?mg/kg植物提取物组绵羊的平均...     

微贮对秸秆在瘤胃NDF降解率的影响

试验采用3个重复对比设计，将玉米，小麦和稻草秸秆的微贮样与原样放置在永久瘘管牛体内，分别在6．12、24．36、48和72小时时间点取出样本进行NDF降解率试验测定分析，结果：秸秆处理样NDF在各个时间点的NDF瞬间降解率和有效降解率均极显著优于原样（P＞0．01）而玉米秸秆处理样与小麦和稻草处理样相比差异不显著（P＞0．05）。     

复合植物精油对肉牛生长性能、养分消化及氮代谢的影响

文章旨在评估复合植物精油对肉牛生长性能、营养物质表观消化及氮代谢的影响.试验将平均体重为(203.16±0.29)kg的108头肉牛随机分为3组,每组36头,每6头牛为1个重复.对照组饲喂全混合日粮,同时自由采食小麦秸秆,T1组和T2组分别饲喂全混合日粮+30和60 mg/kg植物精油,自由采食小麦秸秆.经过28周的饲...     

日粮不同NDF水平对山羊内源氮流量的影响

以装有瘤胃、十二指肠、回肠瘘管的山羊为试验动物。采用拉丁方试验设计,探讨4种NDF水平分别为40.70%、38.37%、34.28%、30.36%的日粮对山羊十二指肠、回肠内源氮流量的影响。结果表明:在该试验条件下,日粮NDF水平在30%～40%范围时,十二指肠、回肠内源氮流量差异不显著(P>0.05)     

不同处理对玉米秸秆青贮饲料中性洗涤纤维、酸性洗涤纤维消失率的影响

为研究纤维素酶、乳酸菌、尿素对玉米秸秆青贮饲料营养价值的影响,分别设乳酸菌处理组、纤维素酶处理组、纤维素酶和乳酸菌共同处理组、尿素氨化处理组及对照组进行玉米秸秆青贮饲料的发酵试验。结果表明,纤维素酶和乳酸菌共同添加、尿素的添加,能提高秸秆青贮饲料纤维消失率,进而提高营养价值。     

原料粒度对家禽消化和生产性能的影响

饲料工业很少关注蛋白类原料（如豆粕、肉粉等）的粒度，因其在出厂时已经粉碎，但需要控制谷物等的粒度。     

不同NFC/NDF比对奶山羊瘤胃微生物及瘤胃pH值变化的影响

试验研究了在不同非纤维性碳水化合物/中性洗涤纤维(NFC/NDF)比饲粮条件下诱发奶山羊亚急性瘤胃酸中毒(subacute rumen acidosis,SARA)过程中瘤胃微生物区系和瘤胃pH值的变化。该试验选用6只安装了永久性瘤胃瘘管的泌乳期关中奶山羊为试验动物,采用自身对照试验法,共分4期进行,每期10d,依次饲喂NFC/NDF比为1.02(Ⅰ期)、1.24(Ⅱ期)、1.63(Ⅲ期)、2.58(Ⅳ期)的4种饲粮,以逐渐增加饲粮精料的方法诱导奶山羊发生SARA。结果表明,随着饲粮NFC/NDF比的增大,瘤胃pH值显著降低(P<0.05),并且瘤胃pH值下降幅度也随之加快;随着饲粮NFC/NDF比的增加,淀粉分解菌的数量增幅最显著(P<0.01);饲粮NFC/NDF比为1.63时,瘤胃细菌总数、乳酸杆菌及坏死梭形杆菌的数量显著增加(P<0.05),当该比值为2.58时,埃氏巨型球菌和反刍兽新月单胞菌的数量出现显著增多(P<0.05);原虫数量在Ⅳ期降至最低,而牛链球菌的数量在整个试验期并未出现明显的波动。饲粮NFC/NDF比为1.63时,瘤胃内与碳水化合物分解有关的多数细菌的数量明显增加,SARA期时增幅更为明显,而此时原虫数量为最低。     

不同NFC/NDF比对奶山羊瘤胃微生物及瘤胃pH值变化的影响

试验研究了在不同非纤维性碳水化合物/中性洗涤纤维（NFC/NDF）比饲粮条件下诱发奶山羊亚急性瘤胃酸中毒（subacute rumen acidosis,SARA）过程中瘤胃微生物区系和瘤胃pH值的变化。该试验选用6只安装了永久性瘤胃瘘管的泌乳期关中奶山羊为试验动物,采用自身对照试验法,共分4期进行,每期10d,依次饲喂NFC/NDF比为1.02（Ⅰ期）、1.24（Ⅱ期）、1.63（Ⅲ期）、2.58（Ⅳ期）的4种饲粮,以逐渐增加饲粮精料的方法诱导奶山羊发生SARA。结果表明,随着饲粮NFC/NDF比的增大,瘤胃pH值显著降低（P〈0.05）,并且瘤胃pH值下降幅度也随之加快;随着饲粮NFC/NDF比的增加,淀粉分解菌的数量增幅最显著（P〈0.01）;饲粮NFC/NDF比为1.63时,瘤胃细菌总数、乳酸杆菌及坏死梭形杆菌的数量显著增加（P〈0.05）,当该比值为2.58时,埃氏巨型球菌和反刍兽新月单胞菌的数量出现显著增多（P〈0.05）;原虫数量在Ⅳ期降至最低,而牛链球菌的数量在整个试验期并未出现明显的波动。饲粮NFC/NDF比为1.63时,瘤胃内与碳水化合物分解有关的多数细菌的数量明显增加,SARA期时增幅更为明显,而此时原虫数量为最低。     

不同NFC/NDF比对奶山羊瘤胃微生物及瘤胃pH值变化的影响

试验研究了在不同非纤维性碳水化合物/中性洗涤纤维(NFC/NDF)比饲粮条件下诱发奶山羊亚急性瘤胃酸中毒(subacute rumen acidosis,SARA)过程中瘤胃微生物区系和瘤胃pH值的变化.该试验选用6只安装了永久性瘤胃瘘管的泌乳期关中奶山羊为试验动物,采用自身对照试验法,共分4期进行,每期10d,依次饲喂NFC/NDF比为1.02(Ⅰ期)、1.24(Ⅱ期)、1.63(Ⅲ期)、2.58(Ⅳ期)的4种饲粮,以逐渐增加饲粮精料的方法诱导奶山羊发生SARA.结果表明,随着饲粮NFC/NDF比的增大,瘤胃pH值显著降低(P＜0.05),并且瘤胃pH值下降幅度也随之加快;随着饲粮NFC/NDF比的增加,淀粉分解菌的数量增幅最显著(P＜0.01);饲粮NFC/NDF比为1.63时,瘤胃细菌总数、乳酸杆菌及坏死梭形杆菌的数量显著增加(P＜0.05),当该比值为2.58时,埃氏巨型球菌和反刍兽新月单胞菌的数量出现显著增多(P＜0.05);原虫数量在Ⅳ期降至最低,而牛链球菌的数量在整个试验期并未出现明显的波动.饲粮NFC/NDF比为1.63时,瘤胃内与碳水化合物分解有关的多数细菌的数量明显增加,SARA期时增幅更为明显,而此时原虫数量为最低.     

Effects of intake and forage level on site and extent of digestion of plant cell wall monomeric components by sheep

The objective of this experiment was to study the effects of level of intake and proportion of forage in the diet on site and extent of digestion of plant cell wall monomeric components (phenolics, neutral sugars) by sheep. Four Suffolk wethers (65 kg) with ruminal and duodenal cannulas were fed diets containing 75% (75A) or 25% (25A) alfalfa hay at two levels of intake, 1,700 (high intake, HI) or 1,100 (low intake, LI) g DM/d in a 4 X 4 latin-square design with a 2 X 2 factorial arrangement of treatments. The remainder of the diet consisted primarily of ground corn. Wethers had lower (P less than .05) total tract NDF and ADF digestibilities when fed 75A or at HI. An intake X forage level interaction (P less than .05) was noted for non-core lignin ferulic acid (FA) total tract disappearance, with wethers at LI having the highest, 25A-HI having the lowest, and 75A-HI having an intermediate FA disappearance. Wethers fed at LI had higher (P less than .05) total tract disappearance of non-core lignin p-coumaric acid (PCA). Wethers fed 75A had greater (P less than .05) total tract disappearances of core lignin vanillic acid (VA) and vanillin (VAN). Total tract digestibilities of the neutral monosaccharides glucose (GLC), xylose (XYL), arabinose (ARA) and galactose (GAL) were greater (P less than .05) for LI vs HI treatments. Wethers consuming 75A had greater (P less than .05) total tract ARA and GAL digestibilities, whereas wethers fed 25A had greater (P less than .05) total tract digestibilities of GLC and mannose (MAN). Diet composition and level of intake appear to influence site and extent of digestion of cell wall monomeric components.     

饲料颗粒大小对鸡生产性能和饲料消化能力的影响

<正>饲料颗粒的大小对鸡来说至关重要,因为鸡主要通过饲料颗粒的大小来挑食。因此,要确保鸡采食充足,就必须将饲料加工成最合适的颗粒大小。但是企业在加工制造饲料时,历来很少重视蛋白质粉料的颗粒大小,比如大豆粉料、动物蛋白粉料。在饲料加工上,     

不同NDF/NFE比的日粮对山羊瘤胃发酵参数影响的研究

利用4只(35±2.5)kg装有瘤胃瘘管的徐淮白山羊,采用拉丁方试验设计,饲喂NDF/NFE分别为1.46(A组)、1.2(5 B组)、1.0(3 C组)、0.8(2 D组)的4种日粮,研究其对瘤胃内环境参数的昼夜动态变化规律的影响。结果表明:①瘤胃pH随NDF/NFE的降低而降低,由A组的6.37降至D组的5.86;②乙酸浓度以B组最高,极显著(P<0.01)高于A、C和D组,A、C、D 3组则依次降低(P>0.05);丙酸浓度以B、D两组较高,极显著(P<0.01)高于A和C组;丁酸浓度随NDF/NFE降低而升高,D组最高,极显著(P<0.01)高于C和B组;总VFA浓度B组最高,极显著(P<0.01)高于D组,显著(P<0.05)高于A、C组;乙酸/丙酸比随NDF/NFE比的降低而减小,A组极显著(P<0.01)大于B、C和D组;③瘤胃氨态氮平均浓度随日粮NDF/NFE比的降低而升高,由A组的8.37mg/dL升至D组的13.71mg/dL。     

不同NFC/NDF比对奶山羊瘤胃微生物及瘤胃pH变化的影响

本试验研究了在不同非纤维性碳水化合物/中性洗涤纤维(NFC/NDF)比饲粮条件下诱发奶山羊亚急性瘤胃酸中毒(subacute ruminal acidosis,SARA)过程中瘤胃微生物区系和瘤胃pH的变化.选用6只安装了永久性瘤胃瘘管的泌乳期关中奶山羊为试验动物,采用自身对照试验法,共分4期进行,每期10 d,依次饲...     

Effects of processing barley on its digestion by horses

Four horses were randomly fed a diet containing rolled, micronised or extruded barley; the barley intake was adjusted to supply 2 g starch/kg bodyweight per day. During a 10-day acclimatisation period the horses were also fed 1 kg grass hay/100 kg bodyweight per day. Samples of blood and breath were collected at the end of each period after the test meal of barley had been fed after a 12-hour overnight fast. The glycaemic and insulinaemic responses of the horses were measured as an indication of the pre-caecal digestibility of starch, and postprandial breath hydrogen and methane were measured to detect microbial fermentation of starch. The highest peak serum glucose and serum insulin concentrations were observed after feeding the extruded barley, lower concentrations were observed after feeding the micronised barley and the lowest concentrations were observed after feeding the rolled barley. Breath hydrogen increased within four hours of feeding all the barley diets, and the mean (sd) peak hydrogen concentrations were 98.3 (55.2) ppm for rolled barley, 59.3 (31.5) ppm for micronised barley and 96.1 (51.9) ppm for extruded barley. There were wide variations within individual horses but these concentrations were not significantly different. Breath methane concentrations were very variable and, although there were no significant differences, there was a trend for higher methane concentrations after the feeding of rolled barley.     

Effects of roughage particle size on site of nutrient digestion and digesta flow through the gastrointestinal tract of sheep fed corncob-concentrate diets

An experiment examining nutritional effects of dietary corncob particle size was conducted using ruminal-, duodenal- and ileal-cannulated sheep in a 4 X 4 Latin square design. Site of nutrient digestion and digesta flow were the principal criteria evaluated. Analyses of dry matter (DM), N, starch and neutral detergent fiber (NDF) were performed on feed, feces and digesta samples. Chromic oxide-impregnated paper was used as an external marker to estimate digestibilities at different sites along the gastrointestinal tract. Ruminal pH and volatile fatty acid molar proportions were also determined. All diets (74.9% concentrates: 25.1% corncobs) were pelleted and were similar in ingredient composition but varied in corncob particle size (corncob mean particle sizes were 6.5, 5.4, 1.4 or .8 mm). Dietary crude protein levels differed little among treatments. Starch concentration was higher in diets containing the larger corncob particles while NDF, acid detergent fiber (ADF), cellulose and hemicellulose concentrations were lower in diets containing larger particles, suggesting a reaction between starch and fiber moieties during the pelleting process. Starch flow past the duodenum decreased (P less than .05) as dietary corncob particle size decreased. Apparent NDF digestion before the duodenum was highest for sheep fed diets containing 1.4-mm corncobs (P less than .05). Apparent starch digestion in the small intestine decreased (P less than .05) as dietary corncob particle size decreased. A considerable amount of NDF was apparently digested in the small intestine of sheep consuming diets containing 5.4- and .8-mm corncobs. Likewise, a substantial amount of NDF was apparently digested in the large intestine. Few differences in apparent total tract digestibilities were noted.(ABSTRACT TRUNCATED AT 250 WORDS)     

瘤胃淀粉消化率及消化动力学的研究方法评述

文章探讨了研究瘤胃淀粉消化率及消化动力学的方法存在的缺陷。淀粉消化位点及该位点的消化率对反刍动物从消化道吸收养分的数量和形式具有重大影响。通过皱胃或十二指肠瘘管收集的食糜样品缺乏代表性,而双相指示剂法也不能完全解决这个问题。原位法被广泛应用于瘤胃淀粉消化速率的测定,但关于从尼龙袋中消失的物质被发酵的假设仍有待商酌。并且,原位法一次函数的假设也受到质疑,说明根据消化动力学参数估计瘤胃淀粉消化率的模型需要完善。体外法以反应体系中淀粉消失率或产气量为基础来评估淀粉消化速率,其重要前提是淀粉消化速率不能受反应体系限制。     

Influence of roughage source on kinetics of digestion and passage, and on calculated extents of ruminal digestion in beef steers fed 65% concentrate diets

Roughage sources were compared in flaked milo-based diets that contained 35% chopped alfalfa hay (AH, control diet) or with cottonseed hulls (CSH) or chopped wheat straw (WS) replacing half the AH. Latin square experiments were used to measure total tract digestion coefficients, particulate passage rates (rare earths), liquid turnover rates (Co-EDTA), and rumination time in six growing steers (Exp. 1) and in situ digestion of DM and NDF, ruminal pH and ruminal DM distribution in three mature, ruminally cannulated steers (Exp. 2). Rates of passage from Exp. 1 and rates and extents of digestion from Exp. 2 were used to calculate apparent extent of ruminal digestion (AED). In Exp. 1, total tract digestibilities of DM and NDF were lower (P less than .05) by 7 and 22%, respectively, when CSH, but not WS, were included in the diet. Digestibility of cell solubles was not different (P greater than .10) among diets. Inclusion of WS increased (P less than .10) rumination time by 36%, and CSH increased intake (P less than .10) by 17% over the control diet. In Exp. 2, there tended to be (P less than .20) increased in situ digestion of milo and AH in the WS diet. Measures of ruminal pH were similar for all diets. The AED for AH and milo DM and NDF, and the proportion of total tract NDF digestion occurring in the rumen (50, 47 and 62% for control, CSH and WS diets, respectively), were highest (P less than .05) for the WS diet. This resulted in similar total tract digestibilities for the WS and AH diets. The two low-digestibility roughages had different effects at this concentrate level; wheat straw enhanced apparent extent of ruminal digestion for NDF of other ingredients in the mixed diets, but cottonseed hulls did not.