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1.
ABSTRACT1. The aim of this study was to examine the effect of yeast cell wall (YCW) on performance and physiological responses of broiler chickens under subclinical necrotic enteritis challenge.2. Six treatments in a 2 × 3 factorial arrangement (non-challenged or challenged plus no supplement, YCW or antibiotics (AB)) was used. Each treatment was replicated eight times with 12 birds per replicate. The treatments included: (1) Positive control (PC; no additive, not challenged); (2) Negative control (NC; no additive, with challenge); (3) YCWN = yeast cell wall (2.0 g/kg diet, not challenged; (4) YCWC = yeast cell wall (2.0 g/kg diet, challenged); (5) ABN = zinc bacitracin 50 ppm + Salinomycin 60 ppm, not challenged); (6) ABC = zinc bacitracin 50 ppm + Salinomycin 60 ppm, challenged).3. Eimeria challenge at 9 d of age did not affect feed intake (FI), body weight gain (BWG), FCR or liveability at 10 d. The BWG and FCR at 10 d were greater (P < 0.05) in birds fed YCW or AB (AB) diets relative to the PC or NC groups. On 24 and 35 d, FI, BWG, FCR and flock uniformity (28 d) were greater (P < 0.05) in the challenged groups fed YCW or AB diets compared to NC group.4. Supplementation with YCW ameliorated the negative effects of NE on liver, spleen and bursa weight of birds.5. Necrotic enteritis challenge decreased (P < 0.05) caecal Lactobacillus and Bifidobacterium spp. counts, and increased ileum lesion score and caecal Clostridium perfirngens counts. This was reversed by the addition of either YCW or AB.6. Supplementation with YCW and AB resulted to a greater (P < 0.05) dressing percentage and meat yield (35 d).7. The results indicated that YCW plays a vital role in improving the physiological response and performance of broiler chickens under subclinical necrotic enteritis challenge. 相似文献
2.
1. The effects of enzymatically hydrolysed whole Saccharomyces cerevisiae yeast (HY) and the pellets of yeast cell wall (YCW) on production traits, the microbiology and histo-morphology of the small intestine, and humoral immune responses against Newcastle disease virus (NDV), of Ross 308 broilers were investigated. 2. The control group received a maize-soyabean meal based basal diet for 42 days. In the treated groups the basal diet was supplemented with 1?g/kg of HY and YCW. There were 8 replicate pens per group (n?=?12 birds/pen). 3. HY and YCW supplementation improved live weight (P?=?0·006) and FCR (P?=?0·003) at 42-d as compared with the control group. 4. In the small intestine, Salmonella spp and Escherichia coli numbers were higher (P?=?0·01) in the mucosa and lower (P?=?0·01) in the digesta of the HY and the YCW fed groups at 25?d of age. Lactobacillus in the duodenal and jejunal digesta was higher (P? 5. Following oral challenge with Salmonella pullorum, Escherichia coli and Lactobacillus increased (P?P? 6. Supplementation of HY and YCW increased villus height in the jejunum (P?=?0·02), width of villus in the ileum (P?=?0·034) and number of goblet cells in villi of the jejunum (P?=?0·006) and ileum (P?=?0·01). 7. YCW increased antibody level against NDV at 21 and 42?d of age compared with the control and the HY supplemented diets (P? 8. It was concluded that HY and YCW improved growth and feed efficiency in broilers, and considering the improvements in production traits and humoral immune responses, yeast cell wall may be a better dietary tool than the hydrolysed whole yeast cell as a performance enhancer for broilers. 相似文献
3.
This study was designed to investigate the growth promoting effects of supplementing different sources and concentrations of prebiotic yeast cell wall (YCW) products containing mannanoligosaccharides in starter broilers under an immune stress and Clostridium perfringens challenge. Through a series of 6 individual studies either 240 or 288 newly hatched chicks were randomly distributed to specific dietary treatments. All birds received a commercial infectious bursa disease vaccine at 10 or 15 d age followed by an orally administered Clostridium perfringens challenge on d 15, 16, and 17; or 18, 19, and 20. Weekly BW, feed consumption, and daily mortality were recorded per pen. Each study was terminated after 21 d. Pooled data analysis of all studies revealed no effect between different product sources of YCW. Products from both sources produced a significant improvement in growth rate compared to control birds fed no YCW. However, a blend of two YCW products showed an approximate 15% improvement in growth rate and a 10% reduction in FCR. The optimum dose of any YCW product among those tested was determined to be approximately 250 ppm. Prebiotic YCW additives increased BW and improved feed conversion and may be considered as alternative growth promoters for starting broilers. 相似文献
4.
1. The objective was to investigate the effects of Bacillus subtilis, yeast cell wall (YCW) and their combination on intestinal health of broilers challenged by Clostridium perfringens over a 21-d period. 2. Using a 5 × 2 factorial arrangement of treatments, 800 1-d-old male Cobb 500 broilers were used to study the effects of feed additives (without additive or with zinc bacitracin, B. subtilis, YCW, and the combination of B. subtilis and YCW), pathogen challenge (without or with Clostridium perfringens challenge), and their interactive effects. 3. C. perfringens infection increased intestinal lesions scores, damaged intestinal histomorphology, increased serum endotoxin concentration, cytokine mRNA expression and intestinal population of C. perfringens and Escherichia coli and decreased ileal bifidobacteria numbers. The 4 additives decreased serum endotoxin. Zinc bacitracin tended to decrease cytokine mRNA expression and the intestinal number of C. perfringens and E. coli. B. subtilis, YCW and their combination increased cytokine mRNA expression. B. subtilis and YCW decreased the number of C. perfringens and E. coli in the ileum, and their combination decreased pathogens numbers in the ileum and caecum. 4. In conclusion, B. subtilis, YCW and their combination improved the intestinal health of NE-infected broilers, and could be potential alternatives to antibiotics. 相似文献
5.
A 6‐week broiler study was conducted to evaluate whether subjecting the intestinal microflora of broilers to the effect of weekly variations in feed ingredients could be ameliorated by the inclusion of yeast‐derived feed additives: a yeast cell wall extract (YCW), live yeast culture (LY) or their combination (YCW + LY). Recent changes in ingredient prices have motivated producers to formulate diets not necessarily based primarily on corn and soya bean meal. Intestinal microflora in birds can vary significantly based on the ingredient composition of their diet, and the make‐up of the flora can influence overall bird performance. Within the three nutrient phases of this study, birds were fed either a traditional corn–soya ingredient profile or a variable‐ingredient regimen, which had weekly changes in the ingredient composition. There were consistent ameliorative effects of the yeast treatments in both the corn–soya and the variable‐ingredient groups throughout all 6 weeks, with the YCW + LY combination showing a reduced effect when compared to either product fed alone. The effectiveness of YCW and LY on ameliorating the effects of weekly ingredient variations appeared most effective during the starter and grower phases, but was less significant during the sixth week. 相似文献
6.
The objective of the present study was to evaluate the effects of dietary inulin and sucrose on the fermentation profile of the gastrointestinal microflora in chicken. Day-old broilers (n = 80) were assigned to four dietary treatments, either fed a basal diet or the same diet supplemented with sucrose (4%), inulin (1%) or sucrose and inulin. At day 35, birds were killed and pH, lactate, ammonia, short chain fatty acids (SCFA) and biogenic amines were determined in different parts of the digestive tract. Final body weights and the relative weights of liver, pancreas, crop, gizzard and small intestine were not influenced by treatment. The relative weights of the empty caeca and of the caecal digesta were higher with the diets containing inulin while caecal pH and ammonia were reduced. Lactate concentration was reduced in the crop (p < or = 0.01) and gizzard (p < or = 0.001) of sucrose-fed groups, while it was increased (p < or = 0.01) in the jejunum of inulin-fed group. Ammonia in the crop (p = 0.089) and gizzard (p = 0.067) tended to be lower in the group receiving inulin plus sucrose. Amongst SCFA, only acetate was detected in the crop and gizzard contents that tended to be lower (p = 0.09) in the crop digesta of sucrose plus inulin-fed group. N-butyrate (mol %) was higher (p < or = 0.001) in the caecal digesta of inulin-supplemented groups without affecting total SCFA. Dietary inulin elevated the concentration of putrescine in the jejunal and caecal contents. In the caecal digesta, total biogenic amines were increased (p < or = 0.001) in sucrose plus inulin-fed group without affecting production of biogenic amines in the jejunum. In conclusion, inulin could reduce the pH in the lower gastrointestinal tract of broilers, while sucrose had no acidifying influence in the upper digestive tract. Inulin enhanced the concentration or metabolic activity of butyrate-producing bacteria in the caecum. Further studies are needed to investigate the potential effect of inulin on the intestinal microbial composition. 相似文献
7.
本试验通过添加酵母细胞壁(YCW)研究其在异育银鲫(Carassius auratus gibelio)饲料中的应用效果。结果表明,饲料中添加0.10%酵母细胞壁饲喂15d后,试验组血清SOD活性极显著高于空白对照组(P<0.01);饲喂30d后试验组血清溶菌酶活性显著高于空白对照组(P<0.05);饲喂60d后试验组背肌中RNA/DNA较空白对照组提高12.18%(P>0.05);饲喂60d后试验组前肠皱褶高度极显著高于空白对照组(P<0.01)。表明饲料中添加0.10%酵母细胞壁对异育银鲫的非特异性免疫力具有明显的促进作用,对其背肌中RNA/DNA和肠道发育也具有一定的促进作用。 相似文献
8.
The objectives of the present study were to investigate the toxicity of feed-borne Fusarium mycotoxins on hematology, serum biochemistry, and oxidative stress of broiler chickens, and to evaluate the efficacy of yeast cell wall adsorbent (YCW) in preventing mycotoxins-induced adverse effects. A total of 300 one-day-old Arbor Acres broiler chickens (mixed sex) were randomly divided into 3 groups and received different treatments (5 repetitions per treatment). Treatments were control, naturally contaminated diet (NCD; aflatoxin, 102.08 mg/kg; zearalenone, 281.92 mg/kg; fumonisin, 5,874.38 mg/kg; deoxynivalenol, 2,038.96 mg/kg), and NCD + 2 g/kg of YCW. Broilers fed NCD showed elevated serum alanine transaminase, aspartate transaminase, alkaline phosphatase, γ-glutamyl transferase (GGT), and malondialdehyde (MDA) at 21 d, and alanine transaminase, GGT, creatine kinase, and MDA at 42 d. Higher white blood cell, lymphocyte (LYM), platelet, red blood cell, hemoglobin, hematocrit, and mean corpuscular hemoglobin counts at 21 d, as well as LYM in whole blood and hepatic mRNA expression of heat shock protein 70 at 42 d were also observed in broilers fed with NCD compared with the control diet. However, lower mean corpuscular volume at 42 d and total superoxide dismutase (T-SOD) at both 21 and 42 d were observed in broilers with the NCD treatment when compared with those with the control treatment. Dietary addition of YCW at the level of 2 g/kg in addition to the NCD treatment showed a positive protective effect on GGT, T-SOD in serum, white blood cells, LYM, platelets, and hemoglobin in whole blood at 21 d, and T-SOD, MDA in serum, LYM, mean corpuscular volume in whole blood, and hepatic mRNA expression of heat-shock protein 70 at 42 d. It is suggested that feeding NCD for 42 d might result in a deleterious effect on broiler chickens, and addition of 2 g/kg of YCW can partly attenuate the detrimental effects of the NCD feeding. 相似文献
9.
The yeast cell wall (YCW) preparation, Safmannan, was evaluated as a dietary supplement for adult dogs. Using a 5 x 5 Latin square design with 14-d periods, adult dogs cannulated in the terminal ileum were supplemented with 0, 0.05, 0.25, 0.45, or 0.65% YCW based on daily food allowance. Apparent ileal nutrient digestibility responded cubically (P = 0.07 to 0.10) to YCW supplementation. Ileal nutrient digestibility tended (P = 0.09) to be greater with YCW supplementation compared with control. Apparent total tract digestibility responded cubically (P < 0.05) to YCW supplementation. Total white blood cell and eosinophil counts tended (P < 0.09) to decrease quadratically with YCW supplementation, with the lowest counts at the 0.25% supplementation level, whereas monocyte counts decreased (P < 0.05) linearly with YCW supplementation. Serum immunoglobulin A (IgA) concentrations tended (P = 0.09) to respond cubically to YCW, with the lowest value at the 0.25% supplementation level. Ileal IgA tended (P < 0.09) to respond quadratically, with the greatest ileal IgA concentration at 0.25% YCW. Using serial dilution and plating enumeration techniques, fecal Escherichia coli concentrations decreased linearly (P = 0.01) with YCW supplementation, whereas Clostridium perfringens responded cubically (P = 0.09). Cubic trends were noted for E. coli (P = 0.10) and lactobacilli (P = 0.08) concentrations, as evaluated by quantitative PCR analysis. Total fecal DNA was most similar to the control treatment at 0.25% YCW. Although the effects on immunological indices appear limited, our results suggest that YCW supplementation in dogs at less than 1% may affect ileal and total tract nutrient digestibility, and the colonization of the gut by E. coli may be decreased. 相似文献
10.
This study assessed the effect of dietary supplementation of yeast cell wall (YCW) and live cell yeast (LCY) at different dosages on rumen’s metabolites. Sixty steers were divided into two groups on the basis of their feeding phase: growing and finishing. Growing and finishing groups were each randomly divided into equal three subgroups ( n?=?10): no supplement (growing control), supplemented with YCW, and supplemented with LCY?+?YCW, no supplement (finishing control), supplemented with LCY and supplemented with LCY?+?YCW. Ruminal fluid has been collected before, after 21 and 42 days of experimental period in order to evaluate the volatile fatty acids concentrations and pH values. Statistical analysis showed a significant effect of time ( P?P?n-butyric acid were found, whereas no statistical significances were found among finishing subgroups. 相似文献
11.
1. The addition of yeast cell wall (YCW) mannan fractions or low concentrations of antibiotics to the diet of broilers positively affects gut health by improving intestinal cell morphology and improves feed efficiency and performance; however the exact mechanisms are unclear. Based on these production responses, the objective of this study was to compare the effects of supplementing YCW and bacitracin methylene disalicylate (BMD) in the diet on mRNA levels in the jejunum of 6-week-old broilers. 2. Dietary treatments were a maize-soya control diet and the control diet with the addition of YCW or BMD. Birds (n = 7) from each dietary treatment were randomly selected and killed at d 42. Whole jejunum (with serosa) samples were collected for RNA isolation. Gene expression analysis was performed using the AffymetrixGeneChip Chicken Genome Array (Santa Clara, CA, USA). 3. Supplementation with YCW resulted in 928 genes that were significantly changed (456 down-regulated, 472 up-regulated) and supplementation with BMD resulted in 857 genes that significantly changed (408 down-regulated, 449 up-regulated). In addition, 316 genes were significantly changed by both YCW and BMD (146 down-regulated, 170 up-regulated). 4. BMD increased the expression of genes involved in lipid and carbohydrate metabolism and decreased expression of genes associated with T-helper cell pathways. Gene expression profiles from birds fed on diets containing YCW showed changes on a genomic level that correspond to slower gut cell turnover and therefore increased energy preservation for growth. 5. In conclusion, supplementation with BMD or YCW had similar influences on the number of differentially expressed genes in the jejunum. Biological functions common to both YCW and BMD with positive activation scores included antiviral response and antimicrobial response. Genes that were affected by BMD or YCW classified into both different and common biological functions and pathways related to improved metabolism and health in the jejunum. 相似文献
12.
The aim of this work was to compare the efficacy of a commercially available phytogenic feed additive(PFA) and an antibiotic growth promoter, which was bacitracin methylene disalicylate(BMD), on performance, nutrient retention, caecal colonization of bacteria and humoral immune responses against Newcastle disease in broiler chickens challenged orally with Salmonella enteritidis and Escherichia coli.One-day-old male Cobb 400 broiler chicks(n = 120) were fed with 1) a negative control(NC) diet, which is the basal diet without any added growth promoter, 2) a positive control(PC) diet, the basal diet supplemented with BMD, 500 mg/kg and 3) a diet supplemented with PFA(150 mg/kg) for 39 days and the birds were inoculated with S. enteritidis and E. coli on d 28. Supplementation of PFA improved body weight, feed conversion ratio, retention of N and crude fiber, increased fecal moisture content and decreased digesta transit time as compared with the NC and PC groups(P 0.01). Both the PC and the PFA was found to be equally effective in controlling the surge in numbers of Salmonella and E. coli following oral inoculation of these bacteria as compared with the NC group(P 0.05) at 24 h past inoculation. Caecal content analysis on d 39 indicated lower numbers of Salmonella, E. coli and Clostridium in the PC and PFA groups as compared with the NC group(P 0.05). The number of Lactobacillus in the PFA group was higher than those in the NC and PC groups(P 0.05). Humoral immune response,measured as hemagglutination inhibition titer against Newcastle disease, was better in the PC and PFA groups compared with the NC group(P 0.05) at d 21 but the difference did not last till d 39. The heterophil to lymphocyte ratio was narrower(P 0.001) and alkaline phosphatase activity was higher(P 0.01) in the PFA group as compared with the NC and PC groups on d 39. It was concluded that the PFA, which is animal, environment and consumer friendly, may be used as an effective replacement for common in-feed antibiotics like BMD to enhance broiler performance especially when the birds are exposed to heavy infections on fields. 相似文献
13.
1.?This research was conducted to determine the impact of diet supplementation with yeast cell walls and Yucca schidigera extract on the growth performance, antibody titres, and intestinal tissue histology of layer chicks. 2.?White, 1-d-old, Hy-Line hybrid chicks (n?=?840) were divided into 4 main groups, each comprising 7 replicates of 30 chicks (n?=?210): (1) control; (2) 1000?mg/kg yeast cell walls (YCW) added; (3) 1000?mg/kg Yucca schidigera extract (YE) added; and (4) 500?mg/kg YE?+?500?mg/kg YCW added. The trial lasted 60?d. 3.?Daily weight gain of the chicks was positively affected between d 45-60 in the YE and YCW?+?YE groups compared with the control group. 4.?Overall, feed consumption did not differ between the control and YCW, YE, YCW?+?YE groups during the 60?d study period. Feed efficiency was better in the YE and YCW?+?YE groups than in the control group between d 1-60. 5.?During the 60?d evaluation period, live weight gain, and final live weight were higher in YE and YCW?+?YE groups than in the control group. 6.?Antibody titres against infectious bronchitis and infectious bursal disease did not differ among the 4 treatments, but those for Newcastle disease were higher in the YE?+?YCW groups than in the control, YCW and YE groups on d 45. 7.?There were differences in intestinal histomorphometry between the 4 treatments. The height of the jejunal and ileal villi was greater in the YE and YCW?+?YE groups than in the control and YCW groups 8.?It can be concluded that YCW and YE supplementation for layer chicks is beneficial for growth performance and intestinal histology during the 1-60?d growing period. 相似文献
14.
Feeding broilers barley-based diets requires special consideration primarily due to effects on increased digesta viscosity and decreased nutrient digestion. Pelleting and glucanase supplementation are commonly performed prior to feeding broilers barley-based diets; however, the interaction of these practices is complex. The objective of this study was to establish a comprehensive evaluation of glucanase efficacy including: degree of processing, activity postpelleting, broiler performance, and digesta viscosity. Treatments were arranged in a 5 (diet formulation) × 2 (processing) factorial in a randomized complete block design with 8 replications/treatment. The 5 diet formulations consisted of positive control (PC), negative control (NC), glucanase A (GA) 125 or 1,000 β-Glu-U/kg feed, and glucanase B (GB) 1,000 β-Glu-U/kg feed. The PC and NC diets differed in metabolizable energy by 150 kcal/kg and enzymes were added to NC formulations. Diets were either fed as unprocessed mash or ground pellets. Diet formulation × processing did not interact for feed intake (FI), FCR, or total tract viscosity ( P > 0.05); however, a trend was observed for ending bird weight, demonstrating that for ground pellets, GA 1,000 β-Glu-U/kg feed was improved relative to NC and similar to PC ( P = 0.0903). Benefits associated with GB were not of similar magnitude, perhaps in part due to a 50% decrease in activity postpelleting. In addition, GA benefits were not suggested for unprocessed mash. The main effect processing was significant ( P < 0.0001) demonstrating that broilers fed ground pellets resulted in greater pen ending bird weight, FI, and bird live weight gain (LWG) compared to birds fed unprocessed mash diets. Evaluations of glucanase should go beyond in vitro activity and include live bird performance using feed that has undergone pelleting. 相似文献
15.
本试验旨在研究活性酵母对脂多糖(LPS)应激黄羽肉鸡肠道健康的影响。选取480羽1日龄黄羽肉公鸡,随机分成6个组,分别为抗生素组(基础饲粮+0.025‰抗生素)、抗生素+LPS组(基础饲粮+0.025‰抗生素,注射LPS)、0.05%活性酵母组(基础饲粮+0.05%活性酵母)、0.05%活性酵母+LPS组(基础饲粮+0.05%活性酵母,注射LPS)、0.50%活性酵母组(基础饲粮+0.50%活性酵母)和0.50%活性酵母+LPS组(基础饲粮+0.50%活性酵母,注射LPS),每组8个重复,每个重复10只鸡。试验期56 d。抗生素+LPS组、0.05%活性酵母+LPS组和0.50%活性酵母+LPS组的试验鸡于21、23、25和27日龄每只鸡肌肉注射2 mL 0.2 mg/mL LPS,其余试验鸡肌肉注射等量生理盐水。于21和27日龄注射LPS或生理盐水后2、4、6、8、10、12和24 h测量试验鸡的直肠温度,并检测27和56日龄试验鸡的肠道细胞凋亡指数以及27、35和56日龄试验鸡的肠道食糜微生物数量和肠道形态结构。结果表明:1)与注射生理盐水相比,LPS刺激显著提高了21日龄注射后2 h和27日龄注射后2和4 h黄羽肉鸡的直肠温度(P0.05),显著降低了21日龄注射后12 h和27日龄注射后8 h黄羽肉鸡的直肠温度(P0.05);饲粮中添加活性酵母对黄羽肉鸡的直肠温度无显著影响(P0.05);饲粮中添加活性酵母与肌肉注射LPS对黄羽肉鸡的直肠温度无显著交互作用(P0.05)。2)与注射生理盐水相比,LPS应激显著提高了27日龄黄羽肉鸡的十二指肠和回肠细胞凋亡指数(P0.05);饲粮中添加活性酵母对黄羽肉鸡的肠道细胞凋亡指数无显著影响(P0.05);饲粮中添加活性酵母与肌肉注射LPS对黄羽肉鸡的肠道细胞凋亡指数无显著交互作用(P0.05)。3)与抗生素相比,饲粮中添加0.05%和0.50%的活性酵母显著提高了27、35和56日龄黄羽肉鸡回肠食糜酵母菌数量(P0.05);与注射生理盐水相比,LPS应激对黄羽肉鸡回肠和盲肠食糜微生物数量无显著影响(P0.05);饲粮中添加活性酵母与肌肉注射LPS对黄羽肉鸡肠道食糜微生物数量无显著交互作用(P0.05)。4)与抗生素相比,饲粮中添加0.50%活性酵母显著提高了35日龄黄羽肉鸡的空肠绒毛高度(P0.05);与注射生理盐水相比,LPS应激显著提高了56日龄黄羽肉鸡的十二指肠隐窝深度(P0.05);饲粮中添加活性酵母与肌肉注射LPS对黄羽肉鸡的肠道形态结构无显著交互作用(P0.05)。综上所述,LPS能成功诱导黄羽肉鸡的免疫应激反应,饲粮中添加活性酵母能够提高黄羽肉鸡肠道绒毛高度和食糜中酵母菌数量,改善肠道黏膜及菌群结构,但肌肉注射LPS与饲粮中添加活性酵母无显著交互作用。 相似文献
16.
1. This study aimed to determine the effect of avilamycin (AGP) and a multi-strain Bacillus probiotic (DFM) on the performance, gut histology and microbiology of broilers fed on a mixed grain diet. 2. A total of 800 chicks were allocated to four treatments: a control diet, control+AGP, control+DFM, or control+AGP+DFM. Bodyweight, feed intake and FCR were measured at d 0, 21 and 42. Samples were taken at d42 to determine villus height (VH), crypt depth (CD) and ratio (VH:CD). Mucosal E. coli and Lactobacilli counts were measured at d42. 3. At d42, DFM and AGP+DFM significantly increased weight over the control, with AGP returning an intermediate value. FCR followed a similar pattern. DFM and AGP+DFM significantly increased VH and CD in all gut sections compared to the control. 4. DFM and AGP+DFM reduced E. coli counts compared to control, with AGP reducing caecal counts only, while Lactobacilli counts were increased. 5. Divergent histology and microbiology between treatments highlight the different modes of action of AGP and DFM for improving broiler growth and feed efficiency. 相似文献
17.
The purpose of this study was to investigate the potential benefits of yeast cell wall (YCW) on the gastrointestinal development of weaned calves. Twenty healthy Holstein male calves (BW = 92 ± 8.29 kg and 60 ± 5 d of age) were randomly allocated into 2 groups: CON with no YCW, and YCW (accounted for 0.16% of the basal diet). The dietary concentrate-to-roughage ratio was 40:60. All the calves were fed regularly twice a day at 09:00 and 16:00 and had free access to water. The experiment lasted for 60 d. The results showed that calves fed YCW showed higher ( P < 0.05) length, width, and surface area of papillae in the ventral sac of the rumen as compared to CON. For the dorsal sac of the rumen, the muscularis thickness was thicker ( P < 0.05) in the YCW group when compared with CON group. The villus height of YCW calves was higher ( P < 0.05) than that of CON in the ileum. Calves supplemented with YCW also showed a higher ( P < 0.05) villus height-to-crypt depth ratio in the ileum. The YCW calves exhibited a greater ( P < 0.05) thickness of the wall in the duodenum and jejunum. Calves supplemented with YCW improved ( P < 0.05) the claudin 1 mRNA expression in the ileum and occludin mRNA expression in the jejunum and ileum. The YCW increased ( P < 0.05) the contents of secretory immunoglobulin A in the jejunum and ileum of calves. In conclusion, dietary supplementation with YCW could improve the gastrointestinal development of weaned calves. 相似文献
18.
An experiment was conducted to determine the effects of yeast culture (YC) and modified yeast culture [YC + cell wall product (CWP) containing mannan oligosaccharides] in pig diets on the performance, gut integrity, and blood cell composition of weanling pigs and to determine whether these dietary supplements could replace antimicrobial growth promoters (AGP) in pig diets. A total of 480 weanling pigs (27 d old and 7.8 +/- 0.1 kg of BW) were assigned to 1 of 4 experimental treatments: 1) diets without AGP or YC (control diet); 2) control + AGP; 3) control + 0.125% YC; and 4) control + 0.125% YC + 0.2% CWP. Piglets were fed experimental diets for 5 wk after weaning. Blood samples were collected from 8 piglets at weaning and from 8 piglets per treatment on d 14 and 35 after weaning for blood cell composition. These piglets were slaughtered for measurement of villous length and crypt depth in the jejunal mucosa and microbial profiling on the intestinal digesta. Average daily gain (P = 0.06) and G:F (P = 0.02) were improved for piglets that were fed the supplemented diets compared with piglets that were fed the control diet. Average daily feed intake was unaffected by dietary treatment. Performance was similar in piglets fed diets supplemented with AGP, YC, and YC + CWP. Blood cell composition, villous length, crypt depth, and microbial composition in the gut were unaffected by dietary treatment, but they were affected by time after weaning. Red blood cells, hemoglobin, hematocrit value, mean cell volume, mean cell hemoglobin, percentage of lymphocytes in the leukocyte population, villous length, and crypt depth were greater (P < 0.05) at 5 wk after weaning than at 2 wk after weaning. Eosinophils (P = 0.06) in the leukocyte population tended to be greater at 5 wk after weaning. Concentration of neutrophils in the leukocyte population and percentages of CD4 and CD8 cells were lower (P < 0.02) at 5 wk after weaning. The CD4:CD8 ratio (P = 0.07) tended to be lower at 5 wk after weaning. Results suggest that yeast culture could be an alternative to AGP in the diets of weanling pigs and that addition of CWP to diets containing YC would not improve the performance or health of weanling pigs above that of YC alone. Thus, more insight into the mode of action of YC is needed. 相似文献
19.
本试验旨在研究饲粮添加不同水平酵母硒对爱拔益加(AA)肉仔鸡生长性能、血液血红蛋白含量和红细胞压积、血浆生化指标、器官指数和组织结构变化的影响,进而评价酵母硒对肉仔鸡的生物安全性。试验采用单因子完全随机设计,选用288只1日龄AA肉仔鸡,随机分为4个组,每个组6个重复,每个重复12只鸡(公母各占1/2)。各组分别在玉米-豆粕型基础饲粮中添加0、0.4、2.4和4.9 mg/kg(以硒计)的酵母硒试验。试验期为42 d。结果表明:1)与对照组相比,饲粮添加0.4和2.4 mg/kg酵母硒显著提高了22~42日龄肉仔鸡平均日采食量(P0.05);饲粮添加0.4、2.4和4.9 mg/kg酵母硒显著提高了1~42日龄肉仔鸡平均日增重(P0.05),而各酵母硒添加组之间差异不显著(P0.05)。2)饲粮添加不同水平酵母硒除对21日龄肉仔鸡血浆尿素氮含量和谷胱甘肽过氧化物酶(GSH-Px)活性以及42日龄肉仔鸡血浆GSH-Px活性有显著影响(P0.05)外,对其他血浆生化指标均无显著影响(P0.05)。与对照组相比,各酵母硒添加组21和42日龄肉仔鸡血浆GSH-Px活性随着酵母硒添加水平的增加均显著提高(P0.05),且饲粮添加2.4 mg/kg酵母硒显著降低了21日龄肉仔鸡血浆尿素氮含量(P0.05)。3)饲粮添加不同水平酵母硒对21和42日龄肉仔鸡血液血红蛋白含量和红细胞压积及42日龄肉仔鸡器官指数均无显著影响(P0.05),且并未引起主要器官的组织结构变化。综上所述,肉仔鸡饲粮中酵母硒的添加水平为0.4 mg/kg(饲粮中总硒含量为0.41 mg/kg)时,具有10倍的安全系数,即饲粮中以酵母硒形式添加硒对肉仔鸡是安全的。 相似文献
20.
选用1日龄AA肉鸡600羽随机分成5组,每组设6个重复,每个重复20羽,分别饲喂鱼粉对照日粮和用酵母蛋白粉等能等蛋白替代对照日粮中25%、50%、75%和100%鱼粉的试验日粮,研究用活性酵母蛋白粉替代鱼粉作为蛋白源对肉鸡生长性能以及养分利用率的影响。结果表明:100%替代组的后期增重较对照组提高0.84%(P>0.05),100%替代组的后期及全期料重比较对照组降低2.20%和1.56%,但差异均不显著(P>0.05)。各组之间营养物质的利用率差异不显著(P>0.05)。100%替代组可以降低饲料成本和增重成本。酵母蛋白粉替代肉鸡日粮中的鱼粉是可行的。 相似文献
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