Microstructure of the small intestine in broiler chickens fed a diet with probiotic or synbiotic supplementation

The aim of the study was to determine the effect of dietary supplementation of a probiotic and a synbiotic on the morphometric parameters of the small intestine of broiler chickens. The experiment was conducted on three hundred sixty, one‐day‐old female Ross 308 chicks, which were randomly selected from 20,000 birds and divided into three treatment groups (n = 120) with ten replicates per treatment. The control group (C) was fed a commercial diet, the probiotic group (PRO) was fed the same diet with an added 1% of the probiotic Lavipan® (Lactococcus lactis, Carnobacterium divergens, Lactobacillus casei, Lactobacillus plantarum and Saccharomyces cerevisiae), and the synbiotic group (SYN) was fed the commercial diet with an added synbiotic: 0.8% of the prebiotic RFO (extracted from lupin seeds) and 1% Lavipan®. According to the manufacturer's data, apart from the typical probiotic action,microorganisms contained in the preparation release anti‐bacterial substances (hydrogen peroxide and bacteriocins) and, therefore, are antagonistic towards pathogenic bacteria present in the gut of animals. Supplementation took place in the first seven days of rearing, and all birds had ad libitum access to water and feed during the 42 days of the experiment. On the last day, all birds were slaughtered and samples from three segments of the small intestine were taken. Villi area, height, width and crypt depth ratios were read using Multiscan software. Synbiotic supplementation increased the BWG of broilers from first to tenth day of rearing, compared to the control group. The PRO group had improved villi morphometric parameters of the duodenum. In the jejunum and ileum, both bioactive substances improved villus width and villus surface area. Crypts were deeper in the small intestine of birds supplemented with bioactive substances, which allows greater renewal of the villi. As expected, the intestinal morphometric parameters of broiler chickens benefited from bioactive substance supplementation.     

Effects of probiotic lactic acid bacteria on growth performance,carcass characteristics,hematological indices,humoral immunity,and IGF-I gene expression in broiler chicken

The effects of screened lactic acid bacteria strains were evaluated on growth performance, humoral immunity, and IGF-1 gene expression in broiler chickens. The three dietary groups of negative control fed basal diet, the native LAB probiotic group (NP), and PrimaLac commercial LAB probiotic (PC) were studied. The results revealed that NP and PC diets significantly improved feed conversion ratio and increased body weight, as well as relative weight of carcass compared with group fed NC diet (P?<?0.05). Lymphocyte level was significantly increased in birds fed NP and PC (P?<?0.01), while serum triglycerides and total cholesterol levels were significantly decreased compared with the NC (P?<?0.05). Significant increases were observed in antibody titers against Newcastle disease virus of vaccinated birds (P?<?0.03), and morphological analysis of ileum revealed significant increases (P?<?0.05) in the villus height and villus height/crypt depth in birds fed NP and PC compared with the NC. The dietary significantly increased Lactobacillus spp. (P?<?0.05), while Escherichia coli (P?<?0.04) populations were significantly decreased, and also, the expression of IGF-1 gene in liver tissue of broilers fed NP and PC was significantly increased compared with the NC (P?<?0.05). These results indicated that the identified native LAB strains can be used commercially as a low-cost probiotic in poultry industry of Iran.

     

Effect of Synbiotic and Antibacterial Peptide on Colibacillosis and Immune Regulation in Broiler Chickens

This experiment was to study the effect of synbiotic and antibacterial peptide on growth performance,and the immune regulation of broiler chickens after the E.coli O78 attack. Totally 100 broilers of health 1-day-old Ross 308 were randomly divided into four treatment groups:Synbiotic group (group S) was fed with basal diet+0.3% synbiotic;Antibacterial peptides group (group AP) was fed with basal diet+0.5% antibacterial peptide; Antibacterial peptide+synbiotic group (group SAP) was fed with basal diet+0.3% synbiotic+0.5% antibacterial peptide;Control group (group C) was fed with basal diet,and the growth performance were determined. At the 14th day,10 chickens from each group were randomly selected for muscle injection with E.coli O78 (the attacked control group was named as model group (group M)),and after 24 h,the morbidity,mortality and immune function of chickens in each group were determined. The results showed that compared with control group,the F/G and ADF of groups S and AP were significantly decreased (P<0.05).Before E.coli O78 attack,the bursa index of group SAP was significantly higher than control group (P<0.05),and other groups had no significant difference (P>0.05);While after the E.coli O78 attack,the thymus,spleen and bursa indexes of groups S and AP were significantly higher than control group (P<0.05),the spleen and bursa indexes of group SAP were significantly higher than control group (P<0.05),and the thymus index showed no significant difference (P>0.05).Compared with the group M,the IgA,sIgA and IL-10 of group S showed no significant difference (P>0.05),while the IL-6 levels decreased extremely significantly (P<0.01);The IgA and IL-6 of group AP were extremely significantly decreased (P<0.01),meanwhile the sIgA and IL-10 were significantly or extremely significantly higher (P<0.05;P<0.01); The changed trend of SAP group was the same as the group AP.In conclusion,the synbiotic and antibacterial peptide could improve the feed conversion rate of chickens and they were used alone or combination all could improved chicken immune function after the bacteria attack.     

合生素和抗菌肽对肉仔鸡大肠杆菌病的防制效果及免疫调节作用

试验旨在研究添加自制合生素和新型抗菌肽对肉仔鸡生长性能的影响,以及攻毒后对其免疫功能的调节作用。选取健康的1日龄科宝Ross 308肉仔鸡100只,随机分为4组。自制合生素组（S组）饲喂基础日粮+0.3%合生素;抗菌肽组（AP组）饲喂基础日粮+0.5%抗菌肽;抗菌肽+合生素组（SAP组）饲喂基础日粮+0.3%合生素+0.5%抗菌肽;对照组（C组）饲喂基础日粮。试验期间测定各组肉鸡生长性能;在试验第14天,同时每组随机选取10只肉仔鸡进行大肠杆菌O78攻毒（对照组攻毒后设为攻菌模型组（M组））,观察记录24 h各组鸡的发病和死亡情况,并测定肉仔鸡的免疫功能。结果显示,与对照组相比,S组和AP组料重比和平均日采食量显著降低（P<0.05）,SAP组的法氏囊指数在攻毒前显著升高（P<0.05）,其他各组无显著差异（P>0.05）;攻毒后,S组及AP组的胸腺指数、脾脏指数及法氏囊指数均显著高于对照组（P<0.05）,SAP组的脾脏指数、法氏囊指数均显著高于对照组（P<0.05）,胸腺指数与对照组间无显著差异（P>0.05）。攻毒后S组中IgA、sIgA和IL-10与M组无显著差异（P>0.05）,而IL-6极显著降低（P<0.01）;AP组中IgA和IL-6均极显著降低（P<0.01）,sIgA和IL-10显著或极显著升高（P<0.05;P<0.01）;SAP组的变化趋势与AP组相同。综上所述,日粮中分别添加合生素和抗菌肽可以提高肉仔鸡的饲料转化率;攻菌后,合生素和抗菌肽以及两者联合使用均可以提高肉仔鸡免疫功能。     

Carcass yields,muscle amino acid and fatty acid profiles,and antioxidant indices of broilers supplemented with synbiotic and/or organic acids

The objective of the current research was to explore the possible impacts of dietary supplementation with synbiotic and/or organic acids (OA) on the performance traits, carcass yields and muscle amino acid and fatty acid (FA) profiles of broilers. Randomly, a total of 160 day‐old chicks (Ross 308) were assigned into four equal groups (40 birds each), with each group subdivided into eight replicates (five birds/pen). The control group (CON) fed the basal diet with no supplements, while diets of the treated groups were supplemented with OA (Sodium butyrate 40%; 1 g/kg), synbiotic (comprised Bacillus subtilis, Saccharomyces cerivisiae, Streptococcus faecium, Mannan‐Oligosaccharides and β‐Glucan; 1 g/kg) and equal mix of OA and synbiotic (2 g/kg). Broilers fed the diets supplemented with synbiotic or synbiotic plus OA produced a significantly higher feed utilization efficiency (p = 0.021) and carcass yields (p = 0.038) than the CON and OA‐supplemented groups. The group fed the diet supplemented with the synbiotic showed lowered serum cholesterol (p = 0.049), triglycerides (p = 0.001) and very low density lipoprotein (p = 0.032) when compared with the CON group. Regarding the polyunsaturated FA (PUFA) of breast muscles, synbiotic‐supplemented birds had significantly lower n‐6:n‐3 ratio (p = 0.047), however, a greater hypocholesterolaemic to hypercholesterolaemic FA (H/H) ratio was reported when compared with the CON group (p = 0.002). Among the essential amino acids, the contents of leucine and methionine in the breast (p = 0.032 and 0.007 respectively) and thigh (p = 0.023 and 0.003 respectively) muscles were greater in the synbiotic‐supplemented birds compared with the CON group. In conclusion, the synbiotic‐supplemented diet improved the PUFA:SFA, n‐6:n‐3 and H/H ratios by altering the FA composition of broiler muscles, which are important with regards to human health.     

Effects of lactulose supplementation on performance,blood profiles,excreta microbial shedding of Lactobacillus and Escherichia coli,relative organ weight and excreta noxious gas contents in broilers

This study was to evaluate the effects of lactulose supplementation on performance, blood profiles, excreta microbial shedding of Lactobacillus and Escherichia coli, relative organ weight and excreta noxious gas contents in broilers. A total of 720 ROSS 308 broilers with a body weight of 46 ± 0.1 g (1 day of age) were used in a 28‐d experiment. Broilers were randomly allotted to 4 experiment diets with 12 replicate pens and 15 birds per pen. Dietary treatments were as follows: NC, negative control (without antibiotic); PC, NC + 0.1% tiamulin; L1, NC + 0.1% lactulose; and L2, NC + 0.2% lactulose. Broilers were fed with phase 1 (1–8 day), phase 2 (9–18 day) and phase 3 (19–28 day) diets in the form of mash. During day 1–8, broilers fed the PC and L2 diets had higher (p < 0.05) body weight gain than those fed the NC diet. During day 19–28, broilers fed the L1 and L2 diets had lower (p < 0.05) feed intake than those fed the NC diet. The feed conversion ratio (FCR) was decreased (p < 0.05) in L1 treatment compared with NC treatment. Overall, the FCR was improved (p < 0.05) in all supplementation treatments compared with NC treatment. The apparently metabolizable nitrogen in L1 treatment was higher (p < 0.05) than that in NC treatment at day 28. The excreta Lactobacillus was increased and E. coli was decreased in PC and L2 treatments compared with NC treatment at day 28 (p < 0.05). The excreta NH₃, H₂S and acetic acid contents were decreased (p < 0.05) in L1 and L2 treatments compared with NC treatment. The relative weight of abdominal fat of broilers fed the PC diet was lowest (p < 0.05) compared with other treatments. In conclusion, this study indicated that dietary supplementation of 0.1% or 0.2% lactulose could improve growth performance, decrease excreta E. coli and excreta NH₃ and H₂S contents.     

Effect of dietary probiotic,prebiotic and synbiotic supplementation on performance,immune responses,intestinal morphology and bacterial populations in broilers

This study was conducted to investigate the effects of probiotic (Primalac), prebiotic (TechnoMos) and synbiotic (Primalac + TechnoMos) supplementation on performance, immune responses, intestinal morphology and bacterial populations of ileum in broilers. A total of 240 one‐day‐old broiler chicks were randomly divided into four treatment groups which included 60 birds. Control group did not receive any treatment. The chicks in the second, third and fourth groups were fed probiotic (0.9 g/kg), prebiotic (0.9 g/kg) and probiotic (0.9 g/kg) plus probiotic (0.9 g/kg; synbiotic), respectively, at entire period. Daily feed intake, daily weight gain and feed conversion ratio were evaluated. The birds were immunized by sheep red blood cell (SRBC) on days 12 and 29 of age and serum antibody titres were measured on days 28, 35 and 42. Newcastle vaccines administered on days 9, 18 and 27 to chicks and blood samples were collected on day 42. Intestinal morphometric assessment and enumeration of intestinal bacterial populations were performed on day 42. The results indicated that consumption of probiotic, prebiotic and synbiotic had no significant effect on daily feed intake, daily body weight gain, feed conversion ratio, carcass traits, intestinal morphology and bacterial populations of ileum (p > 0.05). Consumption of prebiotic increased total and IgM anti‐SRBC titres on days 28 and 42 and antibody titre against Newcastle virus disease on day 42 (p < 0.05). Synbiotic increased only total anti‐SRBC on day 28 (p < 0.05). It is concluded that consumption of prebiotic increased humoral immunity in broilers. Therefore, supplementation of diet with prebiotic for improvement of humoral immune responses is superior to synbiotic supplementation.     

Field trial evaluating changes in prevalence and patterns of antimicrobial resistance among Escherichia coli and Enterococcus spp. isolated from growing broilers medicated with enrofloxacin, apramycin and amoxicillin

The present study investigates, under field conditions, the influence of antimicrobial administration on prevalence and patterns of antimicrobial resistance among Escherichia coli and Enterococcus spp. isolated from growing broilers. For this purpose, a group of 16,000 commercial broiler chickens was treated with enrofloxacin from day 1 to day 3, gentamicin from day 19 to day 21, and ampicillin from day 26 to day 28. A control group of 16,000 broilers was placed in the same controlled environment poultry house. Fecal (from both groups) and feed samples were collected at regular intervals. Few E. coli isolates were obtained from either farm environment or poultry feed samples, while enterococci were found to be ubiquitous among these samples. The frequency of resistance against most antimicrobials tested was significantly higher (P < 0.05) in E. coli isolated from broilers receiving intermittent antimicrobial pressure than that from non-medicated broilers, whereas in enterococci these differences were only observed among structurally related antimicrobial drugs and over a short period of time. By the time the broilers reached market age (33 days), several multi-resistant E. coli and enterococci were detected in the feces of the medicated group. Results suggest that antimicrobial resistance in E. coli was mainly medication-dependent, whereas among enterococci, changes observed over time were apparently influenced by factors apart from antimicrobial exposure, namely the resistance organisms previously present in farm environment and those present in feedstuffs.     

Dietary supplementation with acidifiers improves the growth performance,meat quality and intestinal health of broiler chickens

This experiment was conducted to study the effects of dietary supplementation with acidifiers on the growth performance, meat quality, and intestinal health of broiler chickens. A total of 648 male Arbor Acres broiler chickens at 1 d old were randomly divided into 6 groups, and each group consisted of 6 replicates with 18 broilers per replicate. The dietary treatments were as follows: negative control (NC, the basal diet), NC + antibiotic (enramycin, 8 mg/kg, positive control [PC]), NC + phosphoric acid (PA, 0.1, 0.2, and 0.3 g/kg), and NC + lactic acid (LA, 0.3 g/kg). The feeding trial lasted for 42 d. The results showed that the feed-to-gain ratio of the NC + acidifier groups was lower than that of the NC and PC groups from 1 to 42 d (P < 0.05). Compared with the values in the NC group, the pH of breast muscle was significantly higher in the NC + PA (0.2 g/kg) and LA (0.3 g/kg) groups (P < 0.05), and the cooking loss was lower in the breast muscle of the NC + PA (0.1 g/kg) and LA (0.3 g/kg) groups (P < 0.05). In addition, the shear force of the breast muscle and thigh muscle and the pH value in the crop, gizzard and duodenum of the antibiotic and acidifier groups were significantly decreased (P < 0.05). Moreover, the trypsin, chymotrypsin, and lipase activities of the duodenum in the NC + PA (0.2 and 0.3 g/kg) groups, as well as the villus height-to-crypt depth (VH:CD) ratio of the duodenum in the NC + PA (0.1 g/kg) group was significantly greater (P < 0.05) compared with those in the NC group. Meanwhile, the number of total aerobic bacteria, Escherichia coli and Salmonella in the cecum of the NC + PA (0.1 g/kg) and LA (0.3 g/kg) groups were decreased (P < 0.05). Collectively, diet supplementation with acidifiers could improve the growth performance, meat quality, and intestinal health of broilers, in which the effects of PA (0.1 g/kg and 0.2 g/kg) are better than the other supplementations.     

不同硒源及水平对肉鸡组织硒含量及抗氧化功能的影响

本文旨在研究和比较不同硒源及水平对爱拔益加(AA)肉鸡生长性能、组织硒含量和抗氧化功能的影响,并探讨在生产中应用较低水平(0.20 mg/kg)有机硒替代较高水平(0.30 mg/kg)无机硒的可行性.选用1日龄AA肉仔鸡600只,随机分为5组,分别饲喂基础饲粮(对照组)及在基础饲粮中添加0.30 mg/kg硒(以亚硒酸钠形式)(SS组)、0.20 mg/kg硒(以酵母硒形式)(SY Ⅰ组)、0.30 mg/kg硒(以酵母硒形式)(SYⅡ组)和0.30 mg/kg混合硒(亚硒酸钠和酵母硒形式硒各0.15mg/kg)(MS组)的试验饲粮,每组6个重复,每个重复20只鸡.试验期42 d.结果表明:1)SYⅡ组肉鸡前期平均日采食量显著低于对照组(P＜0.05),饲粮添加各水平有机硒均显著降低了肉鸡全期平均日采食量(P ＜0.05或P＜0.01).2)与对照组和SS组相比,添加各水平有机硒均显著提高了肉鸡胸肌中的硒含量(P＜0.01),且以SYⅡ组最高,显著高于其他各组(P＜0.01);SY Ⅰ组和SYⅡ组肉鸡血浆中的硒含量显著高于对照组(P ＜0.05或P＜0.01);添加各水平有机硒均显著提高了42 d肉鸡肝脏中的硒含量(P ＜0.05或P＜0.01).3)在试验前期(1 ～21 d),较SS组,SYⅡ组肉鸡血浆谷胱甘肽过氧化物酶(GSH-Px)和总超氧化物歧化酶(T-SOD)的活性均显著提高(P＜0.05);较对照组,SS组、SY Ⅰ组和SYⅡ组肉鸡肝脏T-SOD的活性均显著提高(P＜0.05或P＜0.01).在试验后期(22 ～42 d),较对照组,SS组、SY Ⅰ组和SYⅡ组肉鸡血浆和肝脏GSH-Px的活性均显著提高(P＜0.05或P＜0.01),各添加有机硒组肉鸡的血浆丙二醛含量均显著降低(P＜0.05或P＜0.01);与对照组相比,MS组肉鸡肝脏过氧化氢酶(P＜0.05)和GSH-Px的活性均显著提高(P＜0.01).由此可知,饲粮添加0.30 mg/kg酵母硒能够提高肉鸡组织硒沉积量,对其生长性能和抗氧化功能的改善效果最佳;饲粮添加0.20 mg/kg的酵母硒替代0.30 mg/kg亚硒酸钠,在改善肉鸡的生长性能、提高组织硒含量和抗氧化功能方面是可行的.     

Effect of a synbiotic on the intestinal microflora of chickens

The current experiment was conducted to evaluate the effect of a synbiotic (Biomin Imbo) on intestinal microflora of Ross broiler chickens. A total of 200 male chickens were randomly divided into 20 groups of 10 birds each, kept in 20 pens (1.5 × 1 m each), and fed for 42 d at different synbiotic levels. Treatments included (1) a basal diet without synbiotics (control), (2) a basal diet with synbiotic levels proposed by the manufacturer, (3) a basal diet with synbiotic levels 25% lower than those proposed by the manufacturer, (4) a basal diet with synbiotic levels 50% higher than those proposed by the manufacturer, and (5) a basal diet with synbiotic levels 25% higher than those proposed by the manufacturer. At the end of the 42-d feeding period, 1 bird was randomly selected from each experimental unit, humanely euthanized, and the cecum was removed to measure the microbial population. The cecal contents were collected in discharge containers for microbial cultures, and counts were conducted after microbial culture. The addition of the synbiotic reduced Escherichia coli and total coliform populations in the intestines of broiler chickens. Conversely, different levels of probiotic increased the numbers of lactobacilli in the intestine of broiler chickens. Concentrations of the synbiotic higher than the recommended levels in the diet increased the lactic acid bacteria population in the gut of broiler chickens.     

Evaluating two multistrain probiotics on growth performance,intestinal morphology,lipid oxidation and ileal microflora in chickens

An experiment was conducted to investigate the supplementation of two commercially available multistrain probiotics as an alternative to antibiotics on growth performance, intestinal morphology, lipid oxidation and ileal microflora in broiler chickens. A total of 280‐day‐old ROSS 308 mixed‐sex broiler chickens with an average initial body weight of 42 ± 0.5 g were randomly divided into four treatments with five replicate cages of 14 birds each cage in a completely randomized design and fed with the following diets for 42 day: (a) control (CON) (antibiotic‐free diet), (b) antibiotic (ANT) (CON + Avilamycin 150 g/ton feed), (c) probiotic A (CON + Protexin^® 150 g/ton feed) and (d) probiotic B (CON + Bio‐Poul^® 200 g/ton feed). The results showed the broilers fed the ANT diet had greater average daily gain than broilers fed the CON diet during day 1–14 (p < 0.05). At day 42, two birds were randomly selected per replicate for evaluation intestinal morphology, lipid oxidation and ileal microflora. birds fed diet supplemented with probiotic A and probiotic B increased villus height and goblet cells numbers in the jejunum and villus height to crypt depth ratio and villus height in the ileum as compared to birds fed CON diet (p < 0.05). The malondialdehyde value was reduced (p < 0.05) in the ANT, probiotic B and probiotic A groups compared with the CON group. The Lactobacillus population was increased and Clostridium spp. population decreased in the ileum of broilers fed diets containing the probiotic B and probiotic A compared with those fed CON diet (p < 0.05). The results from this study indicate that the probiotic A (Protexin^®) and probiotic B (Bio‐Poul^®) used in this trial may serve as alternatives to ANT.     

Effect ofBacillus amyloliquefaciens-based direct-fed microbials and antibiotic on performance,nutrient digestibility,cecal microflora,and intestinal morphology in broiler chickens

Two hundred eighty-eight 1-d-old male Arbor Acres broilers were randomly allocated to 4 treatments to examine the effect of usingBacillus amyloliquefaciens-based direct-fed microbials (DFM) to replace antibiotics in the late growth stage on performance, nutrient digestibility, cecal microflora, and intestinal morphology in broilers. The experimental diets were (1) a negative control (NC) group fed a basal diet without any antibiotics; (2) a positive control (PC) group fed the basal diet with 200 mg/kg of zinc bacitracin; (3) a test group fed the basal diet with 200 mg/kg of zinc bacitracin from d 1 to 21 and 30 mg/kg of DFM from d 22 to 42 (DFM30); and (4) a test group fed the basal diet with 200 mg/kg of zinc bacitracin from d 1 to 21 and 60 mg/kg of DFM from d 22 to 42 (DFM60). The results showed that DFM30 and DFM60 increased BW gain and improved FCR as compared with NC group (P < 0.05). Generally, the PC, DFM30, and DFM60 groups showed increased apparent total tract nutrient digestibility for DM, CP, and AME as compared with the NC group. Both the DFM30 and DFM60 groups decreased cecalEscherichia coli population as compared with the NC group, and increased the population ofLactobacillus as compared with the PC group. The PC, DFM30, and DFM60 groups increased villus height and the ratio of villus height to crypt depth compared with NC. In conclusion, dietary supplementation withB. amyloliquefaciens-based DFM during d 22 to 42 may enhance performance by increasing nutrient digestibility and improving intestinal health in birds fed diets supplemented with zinc bacitracin from d 1 to 21.     

A multi-microbe probiotic formulation processed at low and high drying temperatures: effects on growth performance,nutrient retention and caecal microbiology of broilers

1. Two experiments were conducted to evaluate a multi-microbe probiotic formulation processed at low (LT) or high (HT) drying temperature.

2. In both the experiments, 640 d-old Ross male chicks were randomly allotted to 4 treatments on the basis of initial BW for 35 d experiments.

3. In experiment one, dietary treatments were a negative control (NC; basal diet without any antimicrobial); positive control (PC; basal diet +10?mg/kg avilamycin); basal diet with 0·3% probiotic LT; and basal diet with 0·3% probiotic HT.

4. Improved overall weight gain, FCR and retention of CP were observed in birds fed the PC and probiotic diets when compared with birds fed the NC diet. At d 21, birds fed the probiotic and NC diets had more caecal Bifidobacterium and total anaerobes than birds fed the PC diet; while birds fed the PC and probiotic diets had fewer caecal Clostridium than birds fed the NC diet at d 35.

5. In experiment two, a 2?×?2 factorial arrangement of treatments was employed to evaluate the effects of two concentrations of probiotic HT (0·30 or 0·60%) and avilamycin (0 or 10?mg/kg).

6. Birds fed the 0·60% probiotic HT diet showed improved overall weight gain and CP retention, higher Lactobacillus and Bifidobacterium in the caecum, and reduced Clostridium and coliforms in the caecum. Inclusion of avilamycin improved the overall weight gain and feed intake, and reduced the caecal Clostridium and Bifidobacterium population.

7. In conclusion, high drying temperature had no effect on the efficacy of the multi-microbe probiotic formulation; while the probiotic HT formulation was more effective at the 0·60% level. Moreover, inclusion of avilamycin improved performance of birds but did not have any interaction with probiotics.     

ORIGINAL ARTICLE: Effects of dietary supplementation of synbiotics and phytobiotics on performance,caecal coliform population and some oxidant/antioxidant parameters of broilers

The current study was conducted to evaluate the effects of dietary supplementation of synbiotics and phytobiotics on performance, small intestine weight, pH and caecal coliform counts of broilers. The influences of synbiotics and phytobiotics on oxidant/antioxidant status in the blood of broilers were also assessed. A total of 200 broiler chicks were randomly allotted to four dietary treatments, either fed a basal diet or the same diet supplemented with 1 g/kg synbiotic, 1 g/kg phytobiotic or 1 g/kg synbiotic plus 1 g/kg phytobiotic. The diet supplemented with both synbiotic and phytobiotic had no effect on body weight, body weight gain, feed intake and feed efficiency of broilers at the end of the study (p > 0.05). Neither small intestine weight nor pH was affected by any of the treatments. Supplementation of both synbiotic and phytobiotic to diet decreased the caecal coliform count (p < 0.01). Addition of synbiotics and phytobiotics in combination significantly increased plasma malondialdehyde (MDA) levels (p ≤ 0.05), whereasphytobiotic addition alone showed only a slight increase. Similarly, elevated nitric oxide (NO) level was recorded in the synbiotic‐ and phytobiotic‐fed group and in the phytobiotic‐fed group (p ≤ 0.001). Superoxide dismutase (SOD) activities did not differ between the groups. In conclusion, dietary supplementation of synbiotic and phytobiotic improved the gut health by decreasing the caecal total coliform count, but growth performance was not affected by the supplementations. Further investigations are needed to determine the effects of phytobiotics on oxidative/antioxidative metabolism as regards their compositional analysis.     

Effects of composite antimicrobial peptide on growth performance and health in weaned piglets

This study was conducted to evaluate the effects of composite antimicrobial peptide (CAP) on growth performance and health status in weaned piglets. Over 28 days, 36 weaned piglets (body weight, 10.58 ± 0.99 kg) underwent three treatments: negative control (NC, basal diet), positive control (PC, basal diet + 20 mg/kg colistin sulphate + 50 mg/kg kitasamycin), and CAP treatment (CAP, basal diet with 400 mg/kg CAP). Average daily gain of piglets fed the CAP diet was greater (P < 0.05) than that of piglets fed the PC or NC diet during days 1–7, 8–14 and 15–21. Diarrhea rates of piglets fed the CAP or PC diet were lower (P < 0.05) than those of NC‐fed piglets during days 1–7. Apparent total tract digestibility for dry matter and crude ash in CAP‐fed piglets was greater (P < 0.05) than that of NC‐fed piglets. In the CAP group, Lactobacillus and Bifidobacterium counts were greater (P < 0.05) and Escherichia coli counts were lower (P < 0.05) than numbers for the NC group. Our results indicate that dietary CAP had beneficial effects on growth performance and health status in weaned piglets.     

Effects of supplementing broiler diets with coriander seed powder on growth performance,blood haematology,ileum microflora and economic efficiency

A total of 480 one‐day‐old Arbor Acres broiler chicks were randomly assigned to four dietary groups, each including six replicates (n = 20/replicate). Broilers in the first group (G1) were fed a basal diet without any additives (control). Broilers in groups 2, 3 and 4 (G2, G3 and G4) were fed a basal diet supplemented with 0.1%, 0.2% and 0.4% coriander (Coriandrum sativum L.) seed powder (CSP) respectively. Feeding trials lasted for 42 days, and after that growth, carcass traits, haematological parameters, gut microbiota and economic efficiency (EE) were evaluated. Final body weight (FBW), total weight gain (TWG), total feed intake (TFI) and red blood cell (RBC) counts of broilers in the G4 and G3 treatment groups were significantly higher (p < .05) compared with broilers in the G1 treatment group. The feed conversion ratio (FCR) was better (p < .05) in the G4 treatment group (1.72) than in the G1 treatment group (1.84). Broilers in CSP treatment groups had significantly higher haemoglobin (Hb) concentrations, packed cell volume (PCV) and platelet counts, and had lower (p < .05) Escherichia coli and Clostridium perfringens counts compared with broilers in the G1 treatment group. Dressing, liver, pancreas, bursa and thymus percentages were higher (p < .05) in broilers in the G4 (70.30, 3.18, 0.31, 0.10 and 0.32% respectively) treatment group, compared with broilers in the control (G1) group (66.57, 2.37, 0.23, 0.04 and 0.21% respectively). Broilers in treatment groups G4 and G3 had lower percentages of abdominal fat and lower total bacterial counts (p < .05) than broilers in treatment groups G2 and G1. The highest economic efficiency (EE) was found in treatment group G4, and EE in this group was 13.06% greater than in the control (G1) group.     

Effect of supplementation of multi-microbe probiotic product on growth performance, apparent digestibility, cecal microbiota and small intestinal morphology of broilers

The present study investigated the effect of inclusion of multi-microbe probiotic product on growth performance, apparent digestibility of nutrients, cecal microbiota and small intestinal morphology in broilers. Four hundred days-old Ross chicks were randomly allotted to five treatments on the basis of body weight (BW). Each treatment had four replicates of 20 chicks in each. Experimental diets were fed in two phases, starter (day 0-21) and finisher (day 22-35). Dietary treatments were; basal diet without any antimicrobial (NC), basal diet added with 20 mg Avilamycin/kg of diet (PC), 10(7) cfu multi-microbe probiotic/kg of diet (P1), 10(8) cfu multi-microbe probiotic/kg of diet (P2), and 10(9) cfu multi-microbe probiotic/kg of diet (P3). Overall BW gain and feed conversion ratio were better (p < 0.05) for treatments PC, P2 and P3 compared with NC and P1, with P1 being better (p < 0.05) than NC. Overall feed intake in treatments PC, P1, P2 and P3 were greater (p < 0.05) than NC. Apparent digestibility of dry matter and crude protein were greater (p < 0.05) in treatments PC, P2 and P3 compared with NC, with P1 being intermediate and not different form NC, PC, P2 and P3. At d 21 and 35, treatments PC, P1, P2 and P3 showed lower (p < 0.05) cecal Clostridium and Coliforms count in relation to NC. Moreover, cecal Clostridium (d 21) and Coliforms (d 21 and 35) count were lower (p < 0.05) in treatment PC in relation to P1; with P2 and P3 being intermediate and not different from PC. However, there was no effect of dietary treatments on cecal total anaerobic bacteria and Bifidobacterium spp. count. The villus height of duodenum in treatment PC was greater (p < 0.05) than NC, with P1, P2 and P3 being intermediate. Villus height of ileum in treatment PC was greater (p < 0.05) than in treatments P1 and NC, whereas it remained comparable among treatments PC, P2 and P3. Villus height to crypt depth ratio of ileum was greater (p < 0.05) for treatment PC, P2 and P3 compared with that in P1 and NC. It is concluded that multi-microbe probiotic inclusion at 10(8) and 10(9) cfu/kg diet had beneficial effects on broilers growth performance, apparent digestibility of nutrients and intestinal morphology and can be used as replacement to antibiotics growth promoter in broiler nutrition.     

小檗碱对黄羽肉鸡器官指数、抗氧化能力和肠道免疫功能的影响

【目的】 本试验旨在研究小檗碱对黄羽肉鸡器官指数、抗氧化能力和肠道免疫功能的影响。【方法】 选用1日龄快大型岭南黄羽肉鸡360只,随机分为3组,每组6个重复,每重复20只。对照组（NC）饲喂基础饲粮;抗生素组（PC）饲喂基础饲粮+200 mg/kg土霉素钙+250 mg/kg那西肽;小檗碱组（BBR）饲喂基础饲粮+250 mg/kg小檗碱。在试验第21、42和63天,从每个重复中随机挑选1只接近平均体重的鸡,采集心脏、肝脏、脾脏和法氏囊分别称重,记录重量,计算其器官指数;刮取空肠黏膜,测定超氧化物歧化酶（T-SOD）、总抗氧化能力（T-AOC）、谷胱甘肽过氧化物酶（GSH-Px）活性和丙二醛（MDA）含量;提取空肠黏膜总RNA,合成cDNA,测定紧密连接蛋白与炎症因子相关基因的mRNA表达量。【结果】 小檗碱对黄羽肉鸡器官指数无显著影响（P>0.05）。与对照组相比,在饲粮中添加小檗碱显著提高了63日龄黄羽肉鸡空肠黏膜的总抗氧化能力（T-AOC）,显著降低了63日龄黄羽肉鸡空肠黏膜的丙二醛（MDA）含量（P<0.05）。抗生素组21日龄黄羽肉鸡空肠黏膜的闭合蛋白（Occludin）和闭锁小带蛋白-1（ZO-1）的mRNA表达量均显著高于对照组和小檗碱组（P<0.05）。与对照组和抗生素组相比,小檗碱显著提高了63日龄黄羽肉鸡空肠黏膜的跨膜蛋白-1（Claudin-1）的mRNA表达量（P<0.05）,显著降低了21、42与63日龄黄羽肉鸡空肠黏膜的核苷酸结合寡聚化结构域蛋白1（NOD1）的mRNA表达量（P<0.05）;小檗碱组与抗生素组42日龄黄羽肉鸡空肠黏膜的白介素-1β（IL-1β）和白介素-8（IL-8）的mRNA表达量均显著低于对照组（P<0.05）;与对照组相比,小檗碱显著降低了63日龄黄羽肉鸡空肠黏膜的肿瘤坏死因子-α（TNF-α）、IL-1β、IL-8的mRNA表达量（P<0.05）。【结论】 饲粮中添加250 mg/kg小檗碱可增强63日龄黄羽肉鸡肠道抗氧化能力,改善肠道屏障,降低肠道炎性因子的表达,从而改善肠道免疫功能。     

Effects of essential oil supplementation of a low‐energy diet on performance,intestinal morphology and microflora,immune properties and antioxidant activities in weaned pigs

A total of 144 weaned piglets were used to evaluate the effects of essential oil (EO) supplementation of a low‐energy diet on performance, apparent nutrient digestibility, small intestinal morphology, intestinal microflora, immune properties and antioxidant activities in weaned pigs. Pigs received a low‐energy diet (negative control, NC, digestible energy = 3250 kcal/kg), NC plus 0.025% EO or a positive control diet (PC, digestible energy = 3400 kcal/kg) for 28 days. Growth performance was similar between the EO group and PC group. However, EO supplementation increased (P < 0.05) average daily gain and the apparent digestibility of dry matter, crude protein and energy compared with pigs fed the NC diet. Greater (P < 0.05) villus height and lower (P < 0.05) counts of Escherichia coli and total anaerobes in the rectum in the EO group were observed compared with NC or PC groups. Pigs fed EO diet had higher (P < 0.05) concentrations of albumin, immunoglobulin A (IgA), IgG and total antioxidant capacity and lower fecal score than pigs fed the PC and NC diets. Above all, this study indicates that supplementation of EO to a low‐energy pig diet has beneficial results and obtains similar performance compared with normal energy (PC) diet.