Fermentation Pattern in the Bovine Rumen after Feeding Straight Feeds

The influence of straight feeds on the fermentation pattern in the bovine rumen was investigated by feeding with hay, grass pellets, dried beet pulp with molasses and rolled oats. The study comprised 3 rumenfistulated dairy heifers, and the parameters measured were ammonia, pH and volatile fatty acids (VFA) in the rumen fluid, and non-glucogenic/glucogenic ratio (NGGR) in the VFA mixture.Typical differences related to the structure and chemical composition of the diets were demonstrated by the parameters measured. Fermentation of the easily digestible feeds resulted in so extensive variations that representative means could be obtained only by analyzing samples collected frequently throughout the feeding cycle.Rumen pH was found highly correlated to total VFA concentration for all the feeds examined, and the regression coefficients showed that diets, based upon beets and oats, were fermented under low buffering capacity.     

不同饲喂频率对梅花鹿瘤胃消化代谢的影响

为探讨不同饲喂频率对梅花鹿瘤胃消化代谢的影响 ,选用 4头装置永久性瘤胃瘘管的成年梅花鹿 ,采用 3种饲喂频率 ,按 4× 3拉丁方试验设计 ,对瘤胃内pH值、氨态氮 (NH3 N)和总挥发性脂肪酸 (TVFA)浓度进行了测定 ,并研究了其动态变化规律以及VFA组分百分率。试验结果表明 ,增加饲喂次数 ,可以极显著地提高梅花鹿对粗饲料的采食量和瘤胃内pH值(P <0 0 1 )。不同饲喂次数 ,对瘤胃内NH3 N浓度、TVFA浓度没有显著的影响 (P >0 0 5)。瘤胃内主要代谢参数均随进食而呈现一定的动态变化规律     

Evaluation of diet as a cause of gastric ulcers in horses

OBJECTIVE: To measure pH, volatile fatty acid (VFA) concentrations, and lactate concentrations in stomach contents and determine number and severity of gastric lesions in horses fed bromegrass hay and alfalfa hay-grain diets. ANIMALS: Six 7-year-old horses. PROCEDURE: A gastric cannula was inserted in each horse. Horses were fed each diet, using a randomized crossover design. Stomach contents were collected immediately after feeding and 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, and 24 hours after feeding on day 14. The pH and VFA and lactate concentrations were measured in gastric juice Number and severity of gastric lesions were scored during endoscopic examinations. RESULTS: The alfalfa hay-grain diet caused significantly higher pH in gastric juice during the first 5 hours after feeding, compared with that for bromegrass hay. Concentrations of acetic, propionic, and isovaleric acid were significantly higher in gastric juice, and number and severity of nonglandular squamous gastric lesions were significantly lower in horses fed alfalfa hay-grain. Valeric acid, butyric acid, and propionic acid concentrations and pH were useful in predicting severity of nonglandular squamous gastric lesions in horses fed alfalfa hay-grain, whereas valeric acid concentrations and butyric acid were useful in predicting severity of those lesions in horses fed bromegrass hay. CONCLUSIONS AND CLINICAL RELEVANCE: An alfalfa hay-grain diet induced significantly higher pH and VFA concentrations in gastric juice than did bromegrass hay. However, number and severity of nonglandular squamous gastric lesions were significantly lower in horses fed alfalfa hay-grain. An alfalfa hay-grain diet may buffer stomach acid in horses.     

Effects of an abrupt increase of starch-rich concentrates in the diet of dairy cows on concentrations of volatile fatty acids in the rumen and large intestine and on myoelectric activity of the spiral colon

OBJECTIVES: To describe the effects of an abrupt increase of concentrates in the diet of dairy cows on myoelectric activity of the spiral colon and on fermentation patterns in the rumen and large intestine. ANIMALS: 6 healthy lactating Simmental x Red-Holstein cows. PROCEDURES: The diet of 6 cows implanted with bipolar electrodes in the spiral colon was changed from hay only to a ration of 50% hay:50% starch-rich concentrates during a period of 60 hours. Myoelectric activity of the spiral colon, concentrations of absolute and undissociated volatile fatty acids (VFA), and pH of ruminal and large intestinal contents were monitored before, during, and after the dietary change. RESULTS: Significant changes in patterns of myoelectric activity of the spiral colon were restricted to phases III and IV of the bovine migrating myoelectric complex and to propagation velocity. Significant alterations were not observed in pH or VFA concentrations in ruminal fluid, but pH decreased and VFA concentrations increased significantly in fecal specimens after the change of diet. CONCLUSIONS AND CLINICAL RELEVANCE: Although rumen fluid is of limited value for measurement of certain indicators of fermentation, fecal samples can be used for measurement of pH and VFA concentrations, which serve as indicators of fermentation patterns in the large intestine. Increased concentrations of VFA and low pH in large intestinal digesta have a minimal influence on myoelectric activity of the spiral colon. Increased luminal VFA concentrations are unlikely to play an important role in the etiopathogenesis of motility disorders of the large intestine in cattle.     

Comparison of silage and hay of dwarf Napier grass (<Emphasis Type="Italic">Pennisetum purpureum</Emphasis>) fed to Thai native beef bulls

Both quantity and quality of forages are important in dry season feeding. Eight Thai native beef bulls were arranged in a Completely randomized design to evaluate dwarf Napier namely Sweet grass (Pennisetum purpureum cv. Mahasarakham) preserved as silage or hay on feed intake, digestibility, and rumen fermentation. The animals were fed with forage ad libitum supplemented with concentrate mixture at 1.0% of BW for 21 days; data were collected during the last 7 days. The results showed that there were differences (P?<?0.05) between treatments in dry matter (DM) intake, DM digestibility, and ruminal pH, in which hay feeding gave enhanced feed intake and more favorable ruminal pH. Nevertheless, mean ruminal ammonia nitrogen, total volatile fatty acids (TVFAs), proportion of VFAs, bacterial and protozoal population, and blood urea nitrogen were similar (P?>?0.05) in animals fed silage and hay. Sweet grass is better preserved as hay rather than silage.     

Rumen fermentation response to a direct-fed xylanase enzyme preparation from Thermomyces lanuginosus in sheep

A study was conducted to obtain data on the effects of a fungal fibrolytic enzyme preparation (Rumino-zyme, with 250 FXU/g xylanase activities) from Thermomyces lanuginosus on some rumen fermentation parameters in sheep. Ruminal fluid samples were taken just before the morning feeding and then 2 h and 4 h after feeding. Xylanase activity, pH, concentration of ammonia and volatile fatty acids were measured. The enzyme supplementation did not affect the pH but increased the xylanase activity and the total VFA concentration of the rumen fluid. The molar proportion of acetate increased, propionate was not affected and butyrate decreased after enzyme administration. The concentration of ammonia also decreased after supplementation with the enzyme product. It can be concluded that the xylanase enzyme preparation from T. lanuginosus induced favourable changes in the major rumen fermentation parameters in sheep.     

不同加工方式针茅草对绵羊干物质采食、消化及瘤胃内环境的影响

本试验旨在研究针茅草的不同加工方式对绵羊采食、消化及瘤胃内环境的影响。选用体重[(45±2)kg]、年龄(1.5~2.0岁)相近安装有永久性瘤胃瘘管的乌珠穆沁羯羊48只,随机分为4组,每组12只,分析干草、草颗粒、草块、草粉4种加工方式的针茅草对绵羊干物质采食量、表观消化率及瘤胃液pH及总氮、氨氮、总可利用氮、挥发性脂肪酸浓度的影响。预试期10 d,正试期7 d。结果表明:1)针茅草颗粒的干物质采食量及表观消化率显著高于其他组(P0.05)。2)与其他各组相比,针茅草颗粒组的绵羊食后1 h瘤胃液pH显著降低(P0.05),总氮、氨氮和总可利用氮浓度较高。3)草颗粒组的瘤胃液总挥发性脂肪酸浓度显著高于干草和草粉组(P0.05)。由此可见,针茅草颗粒的干物质采食量、表观消化率以及在绵羊瘤胃内的发酵指标均较优,是饲喂绵羊的最佳利用形态。     

Water intake, pH and ammonia levels in the ruminal contents of sheep fed pelleted feed]

Wethers were studied for the effect of the complete pelleted feed ration on the intake of water and concentration of pH and ammonia in the rumen. The animals consumed daily 1300 g of dry matter of the diet containing 41.81% of meadow hay, 25.8% of barley, 15.37% of sawdust, 14.98% of molasses, 1.32% of urea and 1.24% of vitamin mineral supplement. This feed was given to them for six months. The pelleted diet increased the intake of water (the dry matter consumption remaining the same in the control and experimental group), reduced pH concentration (6.0--6.2) and slightly increased the level of ammonia in the first hour after feeding; this was probably due to a rapid release of nitrogen compounds from the feed and to intensive rumen fermentation.     

Effects of tylosin on concentrations of Fusobacterium necrophorum and fermentation products in the rumen of cattle fed a high-concentrate diet.

OBJECTIVE: To determine effects of tylosin on ruminal concentrations of Fusobacterium necrophorum and fermentation products in cattle during rapid adaptation to a high-concentrate diet. ANIMALS: 6 steers fitted with ruminal cannulas. PROCEDURE: Steers were assigned randomly to 2 treatment groups and switched from a 0 to an 85% concentrate diet during a 4-day period. Cattle received this diet, with or without tylosin (90 mg/steer/d), for 4 weeks. Samples of ruminal contents were collected daily beginning 2 days before the treatment protocol and in the first week of concentrate feeding. Four subsequent samples were collected at weekly intervals. Concentration of F. necrophorum in samples was determined, using the most-probable-number technique. Ruminal pH and concentrations of volatile fatty acids (VFA), lactate, and ammonia also were determined. All steers received both treatments separated by 4 weeks (cross-over design), during which time they were fed alfalfa hay only. RESULTS: In control steers, concentration of F. necrophorum increased in response to the high-concentrate diet. Tylosin-fed steers had lower concentrations of F. necrophorum than control steers at all times during concentrate feeding. However, ruminal pH and concentrations of lactate, VFA, and ammonia did not differ between treatment groups. CONCLUSIONS AND CLINICAL RELEVANCE: Tylosin caused a significant reduction in ruminal concentrations of F. necrophorum during rapid adaptation to a high-concentrate diet but had no effect on fermentation products. The reduction in ruminal concentration of F. necrophorum helps explain the reduction in prevalence of hepatic abscesses reported in tylosin-fed feedlot cattle.     

高谷物日粮促进山羊瘤胃上皮单羧酸转运蛋白1及钠钾ATP酶mRNA的表达

本试验旨在研究高谷物日粮对山羊瘤胃上皮形态结构及单羧酸转运蛋白(monocarboxylate transporter, MCT)和钠钾ATP酶mRNA表达的影响。将10头装有永久性瘤胃瘘管的健康阉割公山羊随机分为饲喂全粗料日粮的对照组(Hay,0%谷物,n=5)和饲喂高谷物日粮的处理组(HG,65%谷物,n=5),试验期为7周。试验开始后,于每周晨饲后的0、2、3、4、6、8和12 h连续采集瘤胃液监测瘤胃pH值的变化,收集其中第0、3、6和12 h的瘤胃液待测挥发性脂肪酸(volatile fatty acid, VFA)浓度。试验的第50天,屠宰采集瘤胃上皮用于形态学及基因定量分析。研究结果显示:与全粗料组山羊相比,高谷物组山羊瘤胃pH值、乙酸浓度及乙丙比都显著下降(P<0.001),而瘤胃丙酸浓度、丁酸浓度及其他VFA浓度都显著升高(P<0.001);高谷物日粮组的瘤胃乳头长度显著高于对照组(P=0.001),瘤胃乳头宽度显著低于对照组(P<0.001),但是两组间的瘤胃乳头表面积并无显著差异;透射电镜结果显示,长期饲喂高谷物日粮导致瘤胃上皮细胞线粒体发生降解;实时定量PCR结果表明,与对照组相比,高谷物日粮显著升高了MCT1(P<0.001)和钠钾ATP酶(P=0.001)的mRNA表达量,显著降低了MCT4的mRNA表达量(P=0.041),但对MCT2的表达没有显著影响(P=0.305);进一步分析这些基因的mRNA表达量与pH值和VFA浓度之间的相关性,结果显示,MCT1和钠钾ATP酶的mRNA表达量与瘤胃pH值和乙酸浓度呈显著负相关,与总VFA、丙酸、丁酸的含量呈显著正相关,而MCT4的mRNA表达量与pH值呈显著正相关,与总VFA、丙酸、丁酸的含量呈显著负相关。以上结果提示:高精料引起的瘤胃pH值下降和VFA的变化可能与瘤胃上皮MCT和钠钾ATP酶表达量的变化相关。研究结果对深入认识高谷物饲喂引发的瘤胃功能紊乱具有重要意义。     

不同精料补饲水平对藏绵羊瘤胃内环境参数的影响

选择1.2岁左右藏绵羊30只,随机分3组,采用单因子分组设计,以青干草为基础日粮,按每只150,300,450 g/d 3种精料水平补饲,研究不同精料补饲水平对藏绵羊瘤胃代谢参数变化规律的影响。结果表明;随精料补饲水平提高,藏绵羊瘤胃液pH值下降,NH3-N浓度、NH3-N浓度平均值、总挥发性脂肪酸(VFA)浓度显著增加(P<0.05)。在本试验条件下,从藏绵羊瘤胃内环境的稳定方面考虑,藏绵羊每日补饲精料300 g效果最佳。     

Effect of feeding frequency on fermentation pattern and microbial activity in the bovine rumen.

The influence of the feeding frequency on the fermentation in the bovine rumen was investigated by a single reversal trial with restricted supply of feed. The study comprised 6 rumen-fistulated dairy heifers fed a complete diet, low in crude fibre, at 2 frequencies. The effect of the treatment was assessed by the parameters: Concentration of microbial metabolites, total counts of microorganism, concentration of adenosine triphosphate (ATP), and fermentative activity in the rumen.Frequent feeding compared to feeding twice daily resulted in marked reduction of the diurnal variation in the concentration of ruminai metabolites without significant influence on the daily means of total VFA and pH, but the molar composition of the VFA mixture and the production rate of VFA were highly affected. The implications of these observations for improved feed utilization to milk production and fattening are discussed.Pronounced increment of the concentration of ATP was found by frequent feeding, but the total counts of microorganisms were found almost unaffected. Since the rate of fermentation was highly correlated with the concentration of ATP, the ATP pool may be an indicator of the fermentative activity of rumen microorganisms.     

瘤胃灌注不同来源淀粉对牦牛瘤胃发酵及血清生化指标的影响

本试验旨在探讨瘤胃灌注不同来源淀粉对牦牛瘤胃发酵及血清生化指标的影响.选用3头装有永久性瘤胃瘘管、体况良好、体重相近[( 244±15) kg]的去势牦牛,采用3×3拉丁方试验设计,对照组按照1.2倍维持能量水平饲喂单一燕麦草(未灌注淀粉),玉米淀粉组和抗性淀粉组分别在对照组的饲喂基础上瘤胃灌注玉米淀粉和抗性淀粉900 g/d.试验分为3期,每期试验18 d(15 d预试期和3d采样期).结果表明:与对照组相比,灌注玉米淀粉和抗性淀粉显著降低瘤胃pH(P ＜0.05),极显著降低瘤胃氨态氮含量(P＜0.01),灌注4h后显著提高瘤胃微生物蛋白质和挥发性脂肪酸含量(P＜0.05).在灌注后4和6h,玉米淀粉组和抗性淀粉组血糖含量显著高于对照组(P＜0.05),血清胰岛素、胰高血糖素和甘油三酯含量与对照组相比差异不显著(P＞0.05),血清尿素氮含量显著低于对照组(P＜0.05).结果提示,瘤胃灌注玉米淀粉和抗性淀粉,降低了牦牛瘤胃氨态氮含量,提高了微生物蛋白质和挥发性脂肪酸含量,提高了血糖含量,降低了血清尿素氮含量,说明牦牛能有效利用不同来源的淀粉.     

The inhibitory effect of bovine rumen fluid on Salmonella typhimurium.

The possible fate of Salmonella typhimurium in the rumen was investigated by monitoring rumen volatile fatty acids (VFA), lactate concentrations and pH over periods which included regular feeding and 48 h starvation. Preparations were made containing 50 per cent rumen fluid from the cow or VFA solutions, and then inoculated with S typhimurium. Viable counts before and after incubation for 24 h at 37 degrees C were compared. Incubation in broths with high concentrations of VFA and low pH resulted in a marked decrease in salmonella numbers, while lower VFA concentrations had little or no inhibitory effect on growth.     

Effects of alfalfa extract, anise, capsicum, and a mixture of cinnamaldehyde and eugenol on ruminal fermentation and protein degradation in beef heifers fed a high-concentrate diet

Four Holstein heifers (360 +/- 22 and 450 +/- 28 kg of BW in Exp. 1 and 2, respectively) fitted with ruminal trocars were used in 4 x 4 Latin square designs to evaluate the effects on ruminal microbial fermentation of the following: Exp. 1, no additive, alfalfa extract (30 g/d, AEX), a mixture of cinnamaldehyde (0.18 g/d) and eugenol (0.09 g/d; CIE1), and AEX and CIE1 in combination; and Exp. 2, no additive, anise oil (2 g/d), capsicum oil (1 g/d), and a mixture of cinnamaldehyde (0.6 g/d) and eugenol (0.3 g/d). Heifers were fed a 90:10 concentrate:barley straw diet (16% CP; 25% NDF) for ad libitum intake. Each period consisted of 15 d for adaptation and 6 d for sampling. On d 16 to 18, DM and water intakes were measured. On d 19 to 21 ruminal contents were sampled at 0, 3, 6, 9, and 12 h after feeding to determine ruminal pH and the concentrations of VFA, L-lactate, large peptides, small peptides plus AA (SPep+AA), and ammonia N. On d 20 and 21, samples of ruminal fluid were collected at 0 and 3 h after feeding to determine protozoal counts. In Exp. 1, CIE1 and AEX decreased (P < 0.05) total DMI, concentrate DMI, and water intake. The increase (P < 0.05) in SPep+AA and the decrease (P < 0.05) in ammonia N when supplementing CIE1 suggest that deamination was inhibited. Treatment AEX increased (P < 0.05) the acetate to propionate ratio, which is less efficient for beef production. Treatment CIE1 increased (P < 0.05) counts of holotrichs. Effects of AEX and CIE1 were not additive for many of the measured metabolites. In Exp. 2, treatments had no effect on ruminal pH, total VFA concentration, and butyrate proportion. The capsicum oil treatment increased (P < 0.05) DMI, water intake, and SPep+AA N concentration and decreased (P < 0.05) acetate proportion, branched-chain VFA concentration, and large peptide N concentration. The cinnamaldehyde (0.6 g/d) and eugenol (0.3 g/d) treatment decreased (P < 0.05) water intake, acetate proportion, branched-chain VFA, L-lactate, and ammonia N concentrations and increased (P < 0.05) propionate proportion and SPep+AA N concentration. The anise oil treatment decreased (P < 0.05) acetate to propionate ratio, branched-chain VFA and ammonia N concentrations, and protozoal counts. The results indicate that at the doses used a mixture of cinnamaldehyde and eugenol, anise oil, and capsicum oil may be useful as modifiers of rumen fermentation in beef production systems.     

氮源和水平对肉牛体外瘤胃发酵特性的影响

为研究氮源和水平对肉牛瘤胃发酵特性的影响,本试验利用体外培养法研究不同水平(0、50、100和200 mg/L)的尿素、亮氨酸、异亮氨酸和缬氨酸对培养液pH、氨态氮、微生物蛋白质、挥发性脂肪酸的影响.结果表明:在体外培养条件下,以亮氨酸和异亮氨酸为氮源,培养液pH和微生物蛋白质浓度分别显著低于和显著高于以尿素为氮源(P＜0.05),以支链氨基酸为氮源培养液氨态氮浓度显著低于以尿素为氮源(P＜0.05),以异亮氨酸为氮源培养液总挥发性脂肪酸、乙酸和丙酸浓度都显著高于其他氮源(P＜0.05);随着氮水平的提高,培养液pH以及氨态氮、微生物蛋白质和丙酸的浓度都显著的升高(P＜0.05);氮源和水平对各指标均存在显著的互作效应(P＜0.05).结果提示,亮氨酸作为氮源更有利于微生物蛋白质的合成;200 mg/L的氮水平有利于瘤胃微生物的发酵;氮源和水平对瘤胃发酵存在互作效应.     

添喂赖氨酸席夫碱 铜配合物对绵羊瘤胃发酵的影响

选用4只体重约40 kg、安装永久性瘤胃瘘管的新疆美利奴羯羊按分期试验设计，分别添喂赖氨酸席夫碱-铜配合物0（第Ⅰ期）、4（第Ⅱ期）、8（第Ⅲ期）g/d·只，以研究不同水平的赖氨酸席夫碱 铜配合物对绵羊瘤胃发酵的影响。结果表明：随着添喂水平的提高，绵羊对玉米秸秆干物质的采食量增加，其中添喂量为8 g/d·只组与0 g/d·只组相比，采食量提高了12.5％（P＜0.05）。瘤胃液pH在4 g/d·只组与对照组之间无明显差异（P＞0.05），添喂8 g/d·只时在前3 h内具有明显减缓瘤胃液pH下降的作用。各组瘤胃液NH3-N含量差异不明显（P＞0.05），但8 g/d·只组的整体瘤胃液NH3-N含量有降低趋势。添喂赖氨酸席夫碱-铜配合物可降低乙酸和TVFA含量，提高丙酸和丁酸含量，使瘤胃发酵由乙酸型向丙酸型转变。本试验结果表明，添喂赖氨酸席夫碱 铜配合物对绵羊瘤胃发酵有一定的调节作用。     

Feed utilization of beef steers fed grass as hay or silage with or without nitrogen supplementation.

Six Hereford steers averaging 256 kg were used in a 2 x 3 factorial arrangement within a 6 x 6 Latin square design to study the effect of forage conservation (silage vs hay) and N supplementation (0, 200 g of fish meal plus 43 g of urea, or 400 g of fish meal) on ruminal characteristics, digestibility, blood urea, and in situ degradability of DM, N, and ADF. Dry matter intake of forage and total DMI did not differ among treatments (P greater than .05) and averaged 5.3 and 5.5 kg, respectively. Steers fed silage had greater (P less than .05) pH and concentrations of ammonia N, isobutyrate, isovalerate, and valerate in the rumen than in the rumen of those fed hay. Nitrogen supplementation increased (P less than .05) concentrations of total VFA and valerate in the rumen. Digestibility of N and ADF was greater (P less than .05) for silage than for hay, and N supplementation increased digestibility of N. Plasma urea concentrations were greater (P less than .05) for steers fed silage than for those fed hay. These data suggest that feed utilization is better with silage than with hay and is increased by N supplementation.     

The effects of diet on water flux and volatile fatty acid concentrations in the rumen of growing beef steers fed once daily

In vivo temporal changes in ruminal liquid flow, liquid volume and VFA concentrations were determined in growing steers following once-daily feeding. Crossbred beef steers (n = 8; 278 +/- 8 kg), used in a crossover design, were trained to consume 180% of their maintenance energy intake within 2 h of either a high-forage (54% hay: 46% concentrate; HF) or high-concentrate (28% hay: 72% concentrate; HC) diet. For each animal on each diet, ruminal VFA concentrations, liquid volumes and liquid dilution rates were determined during a 2-h period before feeding and during three consecutive 2-h periods following feeding. Water was withheld during these periods to observe physiologically rather than behaviorally induced changes. At equal energy intakes, diet alone had no effect on VFA concentrations (P greater than .10), although changes in total VFA, acetic and isobutyric acids differed during the time periods following feeding due to diet (diet x time period interaction; P less than or equal to .10). Ruminal volume and dilution rate were altered in a reciprocal manner due to diet, with greater volumes and lower dilution rates observed in HC than in HF steers. Differences among time periods were observed for dilution rate and propionic acid concentrations. In general, these differences can be explained by comparison of the prefeeding time period with the postfeeding time periods. A numerical, but not statistically significant, increase in ruminal volume was observed following feeding. The effects of diet on volume and liquid dilution rate of the rumen must be considered when assessing total nutrients available for animal absorption.     

日粮添加益生菌对干乳期奶牛生长性能、瘤胃发酵及氮平衡的影响

本研究旨在评估全混合日粮添加益生菌对干乳期奶牛生长性能、瘤胃发酵及氮平衡的影响.试验将体重为(440.92±3.33)kg、平均干乳期为42?d的60头荷斯坦奶牛随机分为2组,每组5个重复,每个重复6头.对照组饲喂玉米-豆粕型全混合日粮,处理组饲喂基础全混合日粮+200?mg/kg益生菌(枯草芽孢杆菌含量:1×106?...