益生菌发酵棉粕对黄羽肉鸡小肠黏膜形态、血清T淋巴细胞亚群及肠道菌群的影响

本试验旨在研究添加不同比例益生菌发酵棉粕对黄羽肉鸡小肠黏膜形态、血清T淋巴细胞亚群及肠道菌群的影响。选用14日龄健康黄羽肉鸡320只,随机分成4组,每组4个重复,每个重复20只鸡,Ⅰ组为空白对照组,Ⅱ、Ⅲ、Ⅳ组分别添加3%、6%和9%发酵棉粕,研究不同添加量对肉鸡生长前期(14～28日龄)、中期(29～45日龄)、后期(46～65日龄)各阶段小肠黏膜形态,中、后期血清T淋巴细胞亚群及后期肠道菌群的影响。研究结果显示:①与Ⅰ组相比,Ⅲ组黄羽肉鸡前、中、后期的十二指肠绒毛高度极显著提高31.90%、25.17%、49.41%(P<0.01),隐窝深度极显著降低9.42%、11.31%、10.83%(P<0.01),V/C极显著提高45.65%、41.19%、67.84%(P<0.01);空肠绒毛高度极显著提高28.72%、28.38%、27.61%(P<0.01),隐窝深度显著或极显著下降6.65%(P<0.05)、6.18%(P<0.01)、7.37%(P<0.01),V/C极显著提高37.84%、36.69%、37.82%(P<0.01);回肠绒毛高度极显著提高76.64%、40.36%、67.20%(P<0.01) ,隐窝深度显著降低4.09%、6.07%、6.02%(P<0.05),V/C极显著提高83.79%、49.27%、78.26% (P<0.01)。②中、后期Ⅳ组黄羽肉鸡CD4⁺/CD8⁺显著提高42.86%、34.95%(P<0.05)。③随着发酵棉粕添加量的增多,黄羽肉鸡的十二指肠、空肠、回肠中乳酸菌的数量逐渐增多,且差异越来越明显,除Ⅱ组十二指肠和空肠段外,其余各组的各肠段差异均显著或极显著(P<0.05;P<0.01)。大肠杆菌和沙门氏菌的数量逐渐减少,且差异越来越明显,除Ⅱ组十二指肠段外,其余各组各肠段差异均显著或极显著(P<0.05;P<0.01)。综上所述,6%发酵棉粕组在提高十二指肠、空肠、回肠绒毛高度、V/C,降低其隐窝深度方面都优于3%、9%发酵棉粕组,而9%发酵棉粕组在提高CD4⁺/CD8⁺、肠道乳酸菌数量和降低大肠杆菌和沙门氏菌数量方面优于3%、6%发酵棉粕组。     

An experimental rat model of salt-sensitive hypertension; biochemical and morphological parameters and sympathetic nervous system

The objective of the study was to outline the characteristics of the development of hypertension and some neurohumoral, haematological and morphological factors contributing to development of high blood pressure in a genetic model of salt-sensitive rat. Characteristics of Dahl salt-sensitive (DS) rats, as compared to their Dahl salt-resistant (DR) controls were as follows: 1) DS rats display higher blood pressure and lower heart rate compared to DR rats as early as 1 month of age at weaning). They gradually develop hypertension at 2 months of age, irrespective of diet. Low-Na diet (0.5% NaCl) does not prevent hypertension but delays its development and ameliorates it. High Na-diet (8% NaCl) exacerbates hypertension. 2) DS rats have retardation in body weight gain. They develop mild hypochromic anaemia. 3) After 2 months of Na loading (3 months of age), DS rats express significantly increased Na and water retention and increased plasma volume by 15% compared to 2.8% increase in DR rats on high-Na diet. 4) DS rats showed renal parenchymal lesions, more pronounced after Na-loading, focal atrophy of cortical tubules, mesangial matrix expansion and glomerulosclerosis. Consistent with high blood pressure were changes in renal arterioles, fibromuscular proliferation, deposition of fibrinoid material in intima. 5) Sodium loading produced increased activity of the sympathetic nervous system (SNS), and sodium restriction reduced SNS responsiveness.     

益生菌发酵驼乳对慢性肾功能衰竭的治疗作用

目的：比较不同菌种发酵的驼乳制品对腺嘌呤所致大鼠慢性。肾功能衰竭（CRF）的缓解作用。方法：采用腺嘌呤复制CRF大鼠模型,以不同发酵剂发酵的驼乳作为受试物进行灌胃干预。通过检测大鼠的饮食饮水情况、排尿量、尿液和血清常规指标及肾脏病理组织学变化,评估各发酵驼乳对CRF大鼠的治疗效果。结果：发酵驼乳均可改善肾功能衰竭大鼠的一般生理状况,可降低大鼠血肌酐（Scr）、尿素氦（BUN）水平,减缓尿蛋白（UP）,调节Ca、P的含量,提高过氧化物歧化酶（SOD）、血清总蛋白（STP）水平,具有保护肾功能的作用,其中LIcaseiZhang发酵的驼乳对CRF大鼠的改善效果最佳。     

Performance and energy metabolism in restrictively fed weanling pigs are not affected by feeding either fermented cereals or their end‐products

To study the effects of feeding fermented cereals or just fermentation end‐products on performance and energy metabolism, 18 restrictedly fed groups of eight pigs each were assigned to one of three dietary treatments: (i) a liquid control diet (C) containing 40% of a mixture of barley and wheat; or (ii) a liquid diet (F) containing 40% fermented barley and wheat; or (iii) a liquid diet as C with the addition of some important fermentation end‐products (FP; organic acids and ethanol) in concentrations similar to those in the fermented F‐diet. Energy and nitrogen balances, heat production, and performance traits were measured during two consecutive periods (days 1–5 and days 6–14). There was a considerable increase in average dry matter intake that tended (p = 0.06) to be higher in the FP‐group than in the other groups. Apparent fecal digestibility of dry matter, ash, nitrogen and energy during period 2 were not affected (p > 0.1). Averaged over both periods, none of the energy metabolism parameters were affected by the diets (p > 0.1). However, there were diet × period interactions for metabolizable energy‐intake (p = 0.07), energy retention (p < 0.05), the respiratory quotient (RQ; p < 0.01) and activity‐related heat production (H_ACT, p = 0.05). Additionally, there were some differences between the diets in the average hourly patterns in RQ and H_ACT. In conclusion, restricted feeding of either 40% fermented cereals nor their fermentation end‐products affected performance and energy metabolism traits in weanling pigs. Nevertheless, lower postprandial activity‐related heat production by pigs given the fermented cereals suggest a stimulating effect of fermented cereals on short term satiety that was not seen in pigs given fermentation end‐products only.     

植物乳杆菌和枯草芽孢杆菌混菌发酵饲料对肉鸡生长性能、屠宰性能和肠道结构的影响

本试验旨在研究发酵饲料在肉鸡饲料中的使用方法和添加比例。在肉鸡饲料中添加0、10%、20%发酵全价饲料,正常制粒,研究其对肉鸡生长性能、屠宰性能及肠道等相关指标的影响,为发酵饲料在肉鸡饲料中的应用提供参考。选择1日龄爱拔益加（AA）健康肉仔公鸡180只,随机分为3个处理,每个处理6个重复,每个重复10只鸡。3个处理组分别饲喂含发酵全价饲料0（F0组）、10%（F10组）、20%的日粮（F20组）,饲养时间42 d。结果表明,从全期来看（1~42日龄）,10%发酵饲料替代组显著降低了料重比（P<0.05）,平均日增重有增加的趋势（P=0.05）。42日龄时,发酵饲料对屠宰性能无显著影响（P>0.05）;20%发酵饲料替代组肉鸡的回肠隐窝深度显著高于对照组和10%替代组（P<0.05）;20%和10%发酵饲料替代组肉鸡十二指肠绒毛长度、十二指肠和空肠的绒毛长度/隐窝深度（V/C）显著高于对照组（P<0.05）。以上结果提示,肉鸡饲料中以10%的发酵全价饲料替代可以降低料重比,提高平均日增重,并对肠道发育有一定的影响。     

Effects of Lactobacillus and Bacillus subtilis Mixed Fermentation Feed on Growth Performance,Slaughter Performance and Intestinal Morphology of Broilers

The purpose of this experiment was to study the usage and proportion of fermented feed in broiler feed.By adding 0,10% and 20% fermented complete formula feed to the broiler feed,and granulating normally,the influence of the usage mode of the fermented feed on the production performance,slaughter performance,intestinal tract and other related indexes of the broiler feed were studied,so as to provide reference for the application of the fermented feed in the broiler feed.180 1-day-old healthy AA male broilers were randomly divided into 3 groups with 6 replicates in each group and 10 chickens in each replicate.The three treatment groups were fed with 0,10% and 20% of the total fermented feed for 42 days.The results showed that:From the whole period (1-42 days old),the 10% fermentation feed substitution group significantly reduced the feed consumption and weight gain ratio (P<0.05),and the average daily weight gain increased (P=0.05).At 42 days old,there was no significant effect of fermented feed on slaughter performance (P>0.05).The ileal crypt depth of broilers in the 20% fermentation feed replacement group was significantly higher than that in the control group and the 10% replacement group (P<0.05).The length of duodenal villi and V/C in 20% and 10% fermentative feed substitution group was significantly higher than that in control group (P<0.05).The results showed that the replacement of 10% fermented feed in broiler feed could reduce the ratio of feed to weight gain,increase the average daily gain,and have a certain impact on intestinal development.     

Changes in rumen microbial fermentation are due to a combined effect of type of diet and pH

Low ruminal pH may occur when feeding high-concentrate diets. However, because the reduction in pH occurs at the same time as the amount of concentrate fed increases, the changes observed in rumen fermentation may be attributed to pH or the type of substrate being fermented. Our objective was to determine the contribution of pH and type of substrate being fermented to the changes observed in rumen fermentation after supplying a high-concentrate diet. Eight dual-flow, continuous culture fermenters (1,400 mL) were used in 4 periods to study the effect of pH and type of diet being fermented on rumen microbial fermentation. Temperature (39 degrees C), solid (5%/h), and liquid (10%/h) dilution rates, and feeding schedule were maintained constant. Treatments were the type of diet (FOR = 60% ryegrass and alfalfa hays and 40% concentrate; CON = 10% straw and 90% concentrate) and pH (4.9, 5.2, 5.5, 5.8, 6.1, 6.4, 6.7, and 7.0). Diets were formulated to have similar CP and ruminally undegradable protein levels. Data were analyzed as a mixed-effects model considering the linear, quadratic, and cubic effects of pH, the effects of diet, and their interactions. Semipartial correlations of each independent variable were calculated to estimate the contribution of each factor to the overall relationship. True digestion of OM and NDF were affected by pH, but not by type of diet. Total VFA were reduced by pH and were greater in CON than in FOR. Acetate and butyrate concentrations were reduced by pH but were not affected by diet. Propionate concentration increased as the pH decreased and was greater in CON than in FOR. Ammonia-N concentration decreased with decreasing pH and was lower in CON than in FOR. Microbial N flow was affected by pH, diet, and their interaction. Dietary N flow increased as pH decreased and was greater in CON than in FOR. The degradation of CP followed the opposite pattern, increasing as pH increased, and was less in CON than in FOR. The efficiency of microbial protein synthesis (g of N/kg of OM truly digested) was slightly reduced by pH and was less in CON than in FOR. These results indicate that the effects of feeding a high-concentrate diet on rumen fermentation are due to a combination of pH and substrate. Furthermore, the digestion of OM in high-concentrate diets is likely limited by the pH-induced effects on the microbial population activity.     

分离自蒙古国发酵乳制品的保加利亚乳杆菌产酸特性及发酵乳的酸组分

以保加利亚乳杆菌生产菌株结合实验室不同分离源的库存菌株为研究对象,评价保加利亚乳杆菌后酸化过程.选取12株分离自蒙古国不同地区发酵乳制品中保加利亚乳杆菌菌株结合1株商业菌株为研究对象并发酵酸奶,在发酵完成后的低温贮藏阶段(0～48 h、7d、14d和21 d),分别测定菌株发酵酸奶所需时间、贮藏期间滴定酸度、pH值以及采用反相高效液相色谱法测定有机酸含量,综合发酵产酸特性和酸奶后发酵过程中酸组分含量变化,最终得到弱后酸化菌株IMAU20458.     

Isolated canine and murine intestinal cells exhibit a different pattern of fuel utilization for oxidative metabolism

The amount and type of dietary fiber influences the end-products of fermentation and thus fuel availability to intestinal tissue. Metabolic fuel usage was studied in intestinal cells isolated from dogs consuming a commercial diet or from rats consuming either a commercial rat diet or dog diet to examine preferential fuel usage, the effect of diet, and species differences. Production of 14CO2 was measured by incubating cells in media containing either D-[U-14C]glucose, [1-14C]n-butyrate, L-[U-14C]glutamine, or [1-14C]propionate with or without competing substrates. The presence of a mixture of 5 mM each of glucose, butyrate, propionate, and acetate and 1 mM glutamine in the media decreased CO2 production from glucose, glutamine, and propionate by canine enterocytes (P < 0.05) and from glutamine and propionate by canine colonocytes (P < 0.05). The presence of glutamine in the media decreased glucose oxidation by murine enterocytes, regardless of the diet. Similarly, glutamine decreased glucose oxidation by murine colonocytes (P < 0.05), but only when the rats had consumed the rat diet. Regardless of diet, murine colonocytes oxidized more butyrate (P < 0.01) than did enterocytes, and murine enterocytes tended (P < 0.07) to oxidize more glucose than did colonocytes. The proportion of propionate in colonic contents was higher in dogs than in rats (P < 0.02), and the proportion of butyrate tended to be higher in contents from rats than in those from dogs (P < 0.08). Colonic and cecal wet weights were decreased (P < 0.05) when rats were fed the commercial dog diet. Preferred utilization of substrates by isolated canine enterocytes and colonocytes differed from that of murine intestinal cells. These differences were only partially overcome by feeding the same diet to each species.     

Fish-Induced Anemia in Rats

The described feeding experiment on rats comprised three groups, each consisting of 9 females. The control group was fed a commercial pellet diet fortified with brewer’s yeast and whole milk. Groups II and III were fed pasty fish diets which contained 90.5 % of undehydrated raw or boiled coalfish. The feeding experiment started when the rats were 34 days old. The rats were mated three times during the experiment.Undiversified feeding with a raw coalfish diet to rat females during gestation and lactation, and to their litters during weaning and after-weaning, resulted in evident anemic symptoms in the young animals. If boiled fish substituted the raw fish, the anemic symptoms were reduced, but not eliminated.Repeated gestation periods of mother animals, fed fish diets, did not result in increased anemic symptoms in their litters. Nor did the repeated gestation periods result in anemic mother animals.The anemic young rats, when continously fed the same fish diets, gradually improved their health state. The resulting adult animals were non-anemic and appeared normal as to growth and development.     

Effects of fermented mushroom (Flammulina velutipes) by‐product diets on growth performance and carcass traits in growing‐fattening Berkshire pigs

This study was conducted to investigate effects of fermented mushroom (Flammulina velutipes) by‐product diets on the growth performance and carcass traits in growing‐fattening Berkshire pigs. The fermented diets mainly contained 40.0% mushroom by‐product, 20.0% formula feed, 26.0% rice bran and supplemental 0.1% probiotics. The mixed ingredients were fermented for 5 days at room temperature. Berkshire pigs (n = 225) were divided into five groups and three replications. The basal diets (C) were substituted by 10% (T1), 30% (T2), 50% (T3) and 70% (T4) fermented mushroom by‐product diets. Crude protein concentration and total calorie in fermented diets were significantly increased (P < 0.05) at the end of fermentation days compared with initial fermentation day. Body weight gain, feed efficiency and carcass weight were significantly lower (P < 0.05) in the T2, T3 and T4 groups than in the control group. Carcass grade was significantly better (P < 0.05) in the pigs fed fermented diets than in the pigs fed control diet and the ratio of high grade (1 plus 2 grades) was higher in the fermented diet groups compared with the control group. Therefore, although a diet of fermented mushroom by‐product decreased growth performance and feed efficiency, it improved the carcass grade in Berkshire pigs.     

Dietary carbohydrates affect caecal fermentation and modify nitrogen excretion patterns in rats. I. Studies with protein-free diets.

In a two-factorial experiment on 96 young male rats, the effects of substituting 10% raw potato starch (PS), pectins (PEC), or cellulose (CEL) for corn starch (CS) were studied using an unsupplemented protein-free (PF) diet or a PF diet supplemented either with DL-methionine or urea. The pH and the short chain fatty acids (SCFA) content in caecal digesta, as well as caecal digesta and tissue weights were determined and used as the criteria of caecal fermentation intensity. Blood urea level, amount of N excreted via faeces and urine, DAPA content, and amino acid composition of faecal protein were analyzed as indices of protein metabolism. A 10-day adaptation period to the carbohydrates fed with the casein diet preceded the experimental period of feeding the respective carbohydrates with protein-free diets. Dietary carbohydrates significantly influenced total and individual SCFA content in caecal digesta, as well as other parameters related to the intensity of fermentation. Potato starch and pectins were more intensively fermented than cellulose. Supplementation of the PF diet with methionine and urea affected only caecal isobutyric and valeric acid content in a way dependent on the carbohydrates present in the diet. Carbohydrates significantly altered the routes of N excretion. Faecal excretion was increased by all carbohydrates studied compared to corn starch, pectins had the most marked effect. Urinary excretion was significantly increased by cellulose (as compared with the PEC and PS groups) and decreased by pectins as compared with all other groups. There was an interaction between the effects of carbohydrates and type of protein-free diet on faecal and urinary excretion. The sum of amino acids in faecal protein was the lowest on the PEC diet, but the amino acid composition expressed as a per cent of total amino acid content was similar in all groups. It can be concluded that dietary carbohydrates alter the excretion patterns of endogenous nitrogen in rats in different ways and that this effect is related to the intensity of their fermentation in the hind gut.     

苜蓿绿汁发酵液发酵条件研究

苜蓿(Medicago sativa)绿汁发酵液作为青贮添加剂,可以提高青贮的质量。在苜蓿绿汁发酵液中添加不同比例的葡萄糖(0%、1%、2%和5%)和氯化钠(0%、0.5%和1%),做3×4正交试验,研究其对绿汁发酵液发酵品质和乳酸菌数量的影响。结果表明:绿汁发酵液中氯化钠和葡萄糖水平及其交互作用对pH值、可溶性碳水化合物、氨态氮和乙酸含量的影响极显著(P<0.01);添加0.5%氯化钠,氨态氮含量和pH值极显著低于0%和1%;可溶性碳水化合物含量极显著高于氯化钠0%和1%添加水平(P<0.01);苜蓿绿汁发酵液中以同时添加0.5%氯化钠和2%葡萄糖的发酵品质最好。     

发酵穿心莲粉对番鸭生产性能、血清生化指标、免疫相关指标、抗氧化指标及肌肉脂肪酸含量的影响

【目的】本试验旨在研究发酵穿心莲粉对番鸭生产性能、血清生化指标、免疫相关指标、抗氧化指标及肌肉脂肪酸含量的影响。【方法】利用复合菌剂（酵母菌和乳酸菌质量比1：1）发酵穿心莲粉,根据发酵前后成分变化对其微生态功能及药用价值进行分析。将450只15日龄体重250 g左右的黑羽番鸭随机分为5组,每组6个重复,每个重复15只。对照Ⅰ组饲喂基础饲粮,对照Ⅱ组在基础饲粮中添加3%穿心莲粉,发酵Ⅰ、Ⅱ和Ⅲ组分别在基础饲粮中添加1%、3%和5%的发酵穿心莲粉,预试期7 d,正试期48 d。分别于16、21、42、70日龄对番鸭称重,于70日龄从每组随机选取6只番鸭（每个重复随机取1只）屠宰,采集血液、左侧胸肌样品,测定血清生化指标、免疫相关指标及抗氧化指标、肌肉脂肪酸含量。【结果】①穿心莲粉经复合菌剂发酵后,活菌数超过2.0×10⁸ CFU/g,粗纤维含量虽有降低但差异不显著（P>0.05）。②发酵Ⅱ组16~70日龄的料重比显著或极显著低于对照Ⅰ组和发酵Ⅲ组（P<0.05;P<0.01）。③发酵Ⅰ、Ⅱ组的屠宰率均显著高于对照Ⅰ、Ⅱ组（P<0.05）。④发酵Ⅱ、Ⅲ组和对照Ⅱ组番鸭血清的IL-2水平均极显著高于对照Ⅰ组和发酵Ⅰ组（P<0.01）。⑤发酵Ⅱ组的血清丙二醛水平极显著或显著低于对照Ⅰ组和对照Ⅱ组（P<0.01;P<0.05）。⑥发酵Ⅱ组的肌肉不饱和脂肪酸、多不饱和脂肪酸及必需脂肪酸含量均显著或极显著高于对照Ⅰ组（P<0.05;P<0.01）。【结论】与基础饲粮组相比,3%发酵穿心莲粉可显著提高番鸭的生产性能、血清IL-2水平、肌肉不饱和脂肪酸和必需脂肪酸含量,减少番鸭脂质过氧化,提高机体抗氧化能力。此外,3%发酵穿心莲粉对番鸭屠宰率和抗氧化能力的影响要显著优于同比例未发酵穿心莲粉。     

发芽玉米对荷斯坦奶牛瘤胃发酵、产奶性能及乳品质的影响

试验旨在研究发芽玉米对荷斯坦奶牛瘤胃发酵、血液成分、产奶性能及乳品质的影响。选取胎次、分娩日龄、产奶量相近的荷斯坦泌乳奶牛15头,试验分为3组,每组5头。对照组饲喂基础日粮(TMR和苜蓿干草),T1、T2组分别在基础日粮中添加20%发芽玉米和20%发酵发芽玉米。结果表明,添加发芽玉米及发酵发芽玉米均能降低瘤胃pH的变化幅度,提高挥发性脂肪酸和氨态氮浓度,但差异均不显著(P＞0.05);与对照组相比,T1、T2组4%乳脂校正乳极显著提高(P＜0.01),并可显著提高T2组的饲料效率(P＜0.05),显著降低乳中体细胞数(P＜0.05);T1、T2组具有降低乳中胆固醇含量的趋势,并对血液成分无显著影响。因此,饲料中添加发芽玉米可改善瘤胃内环境,显著提高产奶量与饲料效率,显著降低乳中体细胞数,且乳中胆固醇含量有降低的趋势。     

发酵豆粕中大分子蛋白质和肽含量对仔猪小肠绒毛结构的影响

本试验旨在研究豆粕中大分子蛋白质和肽含量对仔猪小肠绒毛结构的影响。采用凝胶过滤色谱技术分析豆粕中大分子蛋白质和肽含量。选取40头断奶仔猪,随机分成4个处理:去皮豆粕处理、发酵豆粕C处理、发酵豆粕E处理和动物蛋白处理。试验期5周。结果表明:去皮豆粕中大分子蛋白质含量约占80%,发酵豆粕中约占50%,甚至降至24%;发酵豆粕中肽含量约占19%,去皮豆粕中仅有2.7%。与去皮豆粕处理相比,发酵豆粕C处理十二指肠绒毛高度显著提高(P0.05),发酵豆粕E、发酵豆粕C处理十二指肠、空肠隐窝深度显著下降(P0.05),发酵豆粕E、发酵豆粕C处理十二指肠和空肠的绒毛高度/隐窝深度均显著升高(P0.05)。由此可见,豆粕中大分子蛋白质含量与小肠绒毛高度/隐窝深度呈负相关;发酵豆粕能够在断奶仔猪饲料中使用,并且有效改善断奶仔猪小肠绒毛结构。     

不同乳酸菌发酵乳对高血脂症大鼠肠道菌群的影响

试验旨在探究不同乳酸菌发酵乳对高血脂模型大鼠血脂与肠道菌群的调节作用。将体重为(120±10)g的 40 只 SD 雄性大鼠随机分为空白对照组(C 组)、高脂模型组(M 组)、L. rhamnosus LV108 发酵乳组(LV组)及混合乳酸菌(LV108 发酵乳∶grx08 发酵乳∶grx12 发酵乳=2∶1∶1)发酵乳组(H 组),每组 10 只,建模后干预(1 mL/100 g,1×108 CFU/mL)4 周,测定大鼠血脂及大鼠粪样细菌 16S rDNA 的 V3-V4 区,并对大鼠肠道微生物和血清血脂水平的相关性进行分析。结果表明:LV 组和 H 组大鼠血清中甘油三酯、总胆固醇及低密度脂蛋白胆固醇含量显著降低,体重增长被抑制;LV 组和 H 组中大鼠肠道菌群的丰度及多样性显著提高,且 H 组大鼠肠道菌群的丰度高于 LV 组(P<0.05);LV 组和 H 组大鼠粪便中 Lactobacillus spp.、S24-7 spp 和 Treponema spp.等菌属显著升高,Peptostreptococcus spp.、Clostridium spp.、Turicibacter spp、Escherichia spp.及 Desulfovibrio spp.等菌属显著降低。结果提示,L. rhamnosus LV108发酵乳及混合乳酸菌发酵乳均能改善大鼠血脂水平并恢复大鼠肠道菌群的多样性及菌群构成。     

微贮稻草对奶牛产奶量和乳品质的影响试验

为了研究微贮稻草饲料的制备及其对奶牛产奶量和奶品质的影响,为贵州乳业发展和饲料资源开发提供理论依据和参考数据,试验选用干稻草切碎至3 cm左右,添加微生态制剂密封厌氧发酵,通过微生物的发酵作用制成稻草微贮饲料.选取16头泌乳期奶牛,随机分为2组,每组8头,试验组日粮中添加微贮稻草10 kg,对照组日粮中添加不发酵的稻草秸秆10 kg,每天分早、晚2次饲喂,预饲期15 d,正试期30 d,记录产奶量并采集牛奶样品进行奶品质检测.结果:与对照组相比,饲喂微贮稻草的试验组日均产奶量增加1.46 kg,提高6.9%(P<0.05);乳蛋白含量提高7%(P<0.05),乳糖含量提高6.8%(P<0.05),乳脂率无显著变化.     

Fiber fermentability effects on energy and macronutrient digestibility, fecal traits, postprandial metabolite responses, and colon histology of overweight cats

Considering the different potential benefits of divergent fiber ingredients, the effect of 3 fiber sources on energy and macronutrient digestibility, fermentation product formation, postprandial metabolite responses, and colon histology of overweight cats (Felis catus) fed kibble diets was compared. Twenty-four healthy adult cats were assigned in a complete randomized block design to 2 groups of 12 animals, and 3 animals from each group were fed 1 of 4 of the following kibble diets: control (CO; 11.5% dietary fiber), beet pulp (BP; 26% dietary fiber), wheat bran (WB; 24% dietary fiber), and sugarcane fiber (SF; 28% dietary fiber). Digestibility was measured by the total collection of feces. After 16 d of diet adaptation and an overnight period without food, blood glucose, cholesterol, and triglyceride postprandial responses were evaluated for 16 h after continued exposure to food. On d 20, colon biopsies of the cats were collected under general anesthesia. Fiber addition reduced food energy and nutrient digestibility. Of all the fiber sources, SF had the least dietary fiber digestibility (P < 0.05), causing the largest reduction of dietary energy digestibility (P < 0.05). The greater fermentability of BP resulted in reduced fecal DM and pH, greater fecal production [g/(cat × d); as-is], and greater fecal concentration of acetate, propionate, and lactate (P < 0.05). For most fecal variables, WB was intermediate between BP and SF, and SF was similar to the control diet except for an increased fecal DM and firmer feces production for the SF diet (P < 0.05). Postprandial evaluations indicated reduced mean glucose concentration and area under the glucose curve in cats fed the SF diet (P < 0.05). Colon mucosa thickness, crypt area, lamina propria area, goblet cell area, crypt mean size, and crypt in bifurcation did not vary among the diets. According to the fiber solubility and fermentation rates, fiber sources can induce different physiological responses in cats, reduce energy digestibility, and favor glucose metabolism (SF), or improve gut health (BP).     

Effect of enzyme supplementation of a rye-based diet on xylanase activity in the small intestine of broilers,on intestinal crypt cell proliferation and on nutrient digestibility and growth performance of the birds

1. A study was undertaken to investigate the susceptibility to peptic digestion of exogenous xylanase (EC 3.2.1.8) from Trichoderma longibrachiatum, added to a rye-based diet for broiler chickens, in order to elucidate its possible site of action. 2. It was also designed to investigate the effects of the enzyme (plus exogenous protease EC 3.4-24.28) when added to a rye-containing diet (60% rye/kg diet) on crypt cell proliferation in the mucosa of the small intestine, on short chain fatty acid (SCFA) concentrations in the small intestine digesta and in portal blood and on nutrient digestibilities. 3. In Experiment 1, the enzymes were added at activities 10x and 30x those recommended in commercial practice, but in Experiment 2 the activities were the recommended levels. 4. A significant proportion (estimated to be 15 to 20%) of the xylanase added at the higher concentration (15,000 and 45,000 units/kg diet) remained active in the small intestine of the growing chicken. 5. The crypt cell proliferation rate in birds fed on the control diet (45 cells/2 h) was significantly higher than in birds fed on the diets supplemented with enzyme at the higher level (29 and 33 cells/ 2 h), but there was no significant effect on SCFA. In birds fed on the diet supplemented with enzyme at the commercial level there was no clear-cut effect on crypt cell proliferation but exogenous xylanase could be detected in the small intestine. Intestinal fluid viscosity was reduced and growth performance of the birds was improved by the supplementation with exogenous enzymes. 6. Part of the improvement in growth performance could be ascribed to a 25% increase in the digestibility of nitrogen and a doubling of the digestibility of fat.