首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 875 毫秒
1.
The ability of 2 probiotic cultures (P1 and P2) to reduce environmental Salmonella in commercial turkey flocks 2 wk prior to processing with or without the use of a commercial organic acid (OA) was evaluated. Salmonella-positive flocks were identified 3 to 4 wk before processing by using standard assembled drag swabs. Two weeks after treatment (prior to live haul), drag swabs were used again for Salmonella recovery. In the first trial, 6 Salmonella-positive houses were selected to evaluate 4 treatments: P1 (1.0 × 108 cfu/mL), OA + P1 (1.0 × 108 cfu/mL), OA + P1 (1.0 × 106 cfu/mL), and OA + P2 (1.0 × 106 cfu/mL). Two weeks after treatment, reductions (P <0.05) of Salmonella recovery (90, 100, 100, and 86%, respectively) were observed in all treatments. In the second trial, 22 Salmonella-positive houses were selected to evaluate 6 treatments: control, OA, P1, P2, OA + P1, and OA + P2. Two weeks after treatment, the recovery of Salmonella was significantly reduced (P <0.05) in houses in which P1 and P2 cultures were administered in combination with the OA product. Our results suggest that the administration of selected probiotic candidate bacteria in combination with OA may reduce environmental Salmonella in turkey houses prior to live haul, and that this practice could help to reduce the risk of Salmonella cross-contamination in the processing plant.  相似文献   

2.
The effect of a commercially available lactic acid bacteria probiotic (FM-B11) alone and supplemented with lactose as prebiotic was evaluated for effects on turkey BW during the brooding and growout phases under commercial conditions in 2 experiments. Tag-numbered turkey poults were given the probiotic in either drinking water or feed, and lactose was given in feed. Turkeys were reared in wire pens (4 per treatment) within the brooding house. Experiments were designed for a duration of 26 and 28 d. Only animals from experiment 1 were weighed again before slaughter. Results from both experiments indicate that groups treated with the combination of probiotic and lactose and lactose alone were heavier (P < 0.05) by 15.5 and 17.5% in experiments 1 and 2, respectively, as compared with the control groups. Market BW of turkeys from experiment 1 was higher (P < 0.05) with the combination of probiotic and lactose than the control group by 436 g. Turkeys on the probiotic alone tended to be heavier than the controls (P = 0.0693). The administration of this lactic acid bacteria-based probiotic, supplemented with lactose as prebiotic to turkey poults during the brooding phase, increased BW, and this advantage was further maintained or augmented during the growout phase.  相似文献   

3.
ABSTRACT

1. This study was conducted to investigate the effect of multi-strain probiotic (containing Lactobacillus acidophilus 2.5 × 107 cfu/g, Lactobacillus casei 2.5 × 107 cfu/g, Bifidobacterium thermophilum 2.5 × 107 cfu/g and Enterococcus faecium 2.5 × 107 cfu/g) and single-strain probiotic (Pediococcus acidilactici 1 × 1010 cfu/g) on broiler breeder performance and gastrointestinal health.

2. A completely randomised trial was conducted using 300 broiler breeder hens (Ross 308) aged 51 weeks old which were randomly allocated to 1 of 5 dietary treatments with 6 replicates per treatment in a 10 week trial. Treatments included (1) the basal diet a negative control, (2) basal diet supplemented with 0.1 g/kg multi-strain probiotic (MS), (3) basal diet supplemented with 0.1 g/kg single-strain probiotic (SS), (4) basal diet supplemented with 0.1 g/kg of both of probiotics (MS+ SS) and (5) positive control basal diet supplemented with 0.5 g/kg oxytetracycline antibiotic (OX).

3. Body weight, egg production, yolk weight, eggshell thickness and weight, Haugh unit, fertility and hatchability were determined. Results showed that dietary treatments had no significant effect on total hen house or total hatching egg production, egg weight, yolk colour index, shell weight, mortality, body weight, fertility, hatchability, oviduct and stroma weight or number of large and small yellow follicles (P > 0.05). None of the jejunum morphological parameters, apparent ileal digestibility of protein and ileal Lactobacillus population were influenced by supplemental probiotics (P > 0.05), although ileum Escherichia coli count was reduced by inclusion of dietary probiotics (P < 0.05).

4. It was concluded that although both probiotic treatments reduced coliforms, they did not improve broiler breeder performance or gastrointestinal tract (GIT) function.  相似文献   

4.
The purpose of this study was to evaluate the capacity of a lactic acid bacteria (LAB) inoculum to protect calves with or without lactose supplements against Salmonella Dublin infection by evaluating histopathological lesions and pathogen translocation. Fifteen calves were divided into three groups [control group (C-G), a group inoculated with LAB (LAB-G), and a group inoculated with LAB and given lactose supplements (L-LAB-G)] with five, six, and four animals, respectively. The inoculum, composed of Lactobacillus (L.) casei DSPV 318T, L. salivarius DSPV 315T, and Pediococcus acidilactici DSPV 006T, was administered with milk replacer. The LAB-G and L-LAB-G received a daily dose of 109 CFU/kg body weight of each strain throughout the experiment. Lactose was provided to the L-LAB-G in doses of 100 g/day. Salmonella Dublin (2 × 1010 CFU) was orally administered to all animals on day 11 of the experiment. The microscopic lesion index values in target organs were 83%, 70%, and 64.3% (p < 0.05) for the C-G, LAB-G, and L-LAB-G, respectively. Administration of the probiotic inoculum was not fully effective against infection caused by Salmonella. Although probiotic treatment was unable to delay the arrival of pathogen to target organs, it was evident that the inoculum altered the response of animals against pathogen infection.  相似文献   

5.
The effect of a Lactobacillus spp.-based probiotic (FM-B11) on Salmonella enterica serovar Enteritidis (SE) recovery was evaluated in liquid (Expt. 1) and lyophilized (Expt. 2) forms in two separate experiments with two trials each. For each trial, 80 broiler chicks were randomly allocated into two treatments: control and probiotic culture. All chicks were challenged with SE (approximately 10(4) colony-forming units [cfu]) upon arrival at our laboratory. In both experiments, probiotic culture was administered in the drinking water for 3 consecutive days at a final concentration of approximately 10(6) cfu/ml, beginning 1 hr after SE challenge. Cecal tonsils were aseptically removed at 24 and 72 hr postchallenge, followed by enrichment and plating on xylose lactose deoxycholate (XLD) agar for the presence or absence of Salmonella-typical colonies. In Expt. 1, a significant reduction (P < 0.05) in SE-positive samples was observed in both trials at 24 and 72 hr postchallenge. Additionally, in Expt. 2, the lyophilized probiotic decreased (P < 0.05) SE recovery at both 24 and 72 hr postchallenge compared with the control group in trial 1. In trial 2, SE evaluation was performed only at 72 hr after challenge and fewer (P < 0.001) treated samples were positive for SE. Results showed that application of either liquid or lyophilized probiotic culture in the drinking water for 3 consecutive days can help to reduce SE recovery from young birds, although further research is needed to elucidate the mechanism of this response.  相似文献   

6.
The effect of acidified sodium chlorite (ASC), produced by the combination of sodium chlorite (SC) with citric acid (CA) or sodium acid sulfate (SAS), on Salmonella and Campylobacter reduction in market age broilers was investigated. In the first experiment, the tolerance to increasing concentrations of SC (0, 100, 300, 600, 1,200, 3,000, and 6,000 ppm) and CA (0, 0.003, 0.01, 0.02, 0.04, 0.08, 0.18, and 0.40%) in the drinking water was assessed. In the second experiment, broilers were fasted for 2 h and orally gavaged with 105 cfu of Salmonella enterica serotype Typhimurium 1 h before the initiation of drinking water treatments involving 5 concentrations of SC (0, 150, 300, 600, and 1,200 ppm), acidified to pH of 2.6, either with CA or SAS. In the third experiment, 8-d-old chicks were orally challenged with 105 cfu of Salmonella and 105 cfu of Campylobacter jejuni. On d 29, birds were provided 3 concentrations of SC (0, 300, and 600 ppm) acidified to pH 2.6 ± 0.1 with only water, CA, or SAS for 5 d. In experiment 2 and 3, the challenge organisms were enumerated in the upper, middle, and lower segments of the digestive tract. Water consumption was depressed significantly at levels of SC above 600 ppm and levels of CA above 0.18%. In experiment 2, SC levels above 600 ppm negatively affected water consumption regardless of the acid used. A level of 600 ppm of ASC was adequate to reduce the transient crop Salmonella, whereas 1,200 ppm was required for a significant reduction in the lower digestive tract. In experiment 3, six hundred parts per million of ASC reduced Salmonella only in the upper digestive tract. Campylobacter counts were not affected by SC treatments in experiment 3 (P > 0.05). Preslaughter use of acidified SC in the drinking water may be an effective way to reduce Salmonella in the crop, including those that may be picked up through litter consumption and caprophagy.  相似文献   

7.
Studies were conducted to assess the performance of turkeys fed diets containing lactose. Study 1 consisted of 96, mixed-sex turkey poults that were housed in battery cages and fed diets containing 0 (8% cornstarch), 0.5, 1, 2, 4, or 8% lactose from 0 to 6 wk. Study 2 used 360, mixed-sex turkey poults that were raised in floor pens and fed a commercial diet and diets containing 0 (4% starch), 0.5, 1, 2, or 4% lactose from 0 to 6 wk. Diets and water were offered ad libitum throughout both trials. The objectives were 1) to determine the effect of lactose on turkey performance and 2) to establish the optimum level for lactose inclusion in diets. In Study 1, feed intake, BW, fecal ammonia and nitrogen, and feed efficiency were determined. Diet composition, BW, feed intake, total body and carcass composition, cecal pH, volatile fatty acids (VFA) and lactic acid were measured in Study 2. Turkeys consuming the 4% lactose diet gained the most weight (P < 0.01) compared with other treatments in Study 1, and lactose improved feed efficiency. In Study 2, all lactose diets resulted in heavier BW (P < 0.05) compared with the commercial diet. Turkeys consuming diets with 0.5, 1, 2 or 4% lactose had less total body fat compared with turkeys consuming a commercial or 0% lactose diet (P < 0.05).  相似文献   

8.
Two 28-d experiments were conducted to evaluate the effect of grinding corn or soybean meal (SBM) to various particle sizes on P utilization in turkey poults. Dietary Ca was formulated to be 1.20% in the corn-SBM-based diets of both studies and nonphytate P (NPP) was calculated to be 0.40% in experiment 1 and 0.48% in experiment 2. In experiment 1, corn that had been processed through a roller mill was used or was ground through 3 different screen sizes in a hammer mill to yield 4 corn particle sizes ranging from about 600 to 1,100 μm. Initial (7 d) growth was reduced when the coarsest corn was fed due to lower feed intake. Phosphorus utilization was improved the first 2 wk as corn particle size increased as measured by incidence of rickets, tibia ash, and total P retention. Gizzard weight and phytate P retention were increased at 28 d as corn particle size increased. In experiment 2, corn was ground to approximately 850 μm and commercial SBM (856 μm) was used or ground to 2 finer particle sizes in a hammer mill. Gizzard weight and phytate P retention were increased at 28 d as SBM particle size increased. Other parameters were not affected at least partially due to the higher dietary NPP level fed to prevent severe rickets observed in the first trial. These studies show that young poults can utilize P better from coarser corn and soybean meal, especially when dietary P is low.  相似文献   

9.
The effect of probiotic, Bacillus coagulans NJ0516, on growth performance and digestive enzyme activity of Arbor Acres (AA) broilers was investigated. Strains NJ0516 were added to commercial basal diets as probiotic at three final concentrations: T-1, 1 × 106 cfu g−1; T-2, 2 × 106 cfu g−1 and T-3, 4 × 106 cfu g−1, respectively. Twelve groups, of 30 broilers, with three replicates for each treatment group (T-1, T-2 and T-3) and the control group treated without probiotic were used. After 49 days, broilers receiving the diets supplemented with probiotic showed significantly better growth performances including final weight and daily weight gain (DWG) than those fed the basal diet (control). As for feed conversion ratio (FCR), T-2 and T-3 showed lower value (P < 0.05) than the control. However, there was no significant different in final weight, DWG and FCR between T-1, T-2 and T-3 and the survival rate was not affected (P > 0.05) by the dietary treatments. The higher protease activities were observed in T-2 and T-3 (P < 0.05) compared with the control and T-1. However, there was not significantly different (P > 0.05) between T-2 and T-3 in protease activity. Amylase activity in T-1, T-2 and T-3 was remarkably higher (P < 0.05) than that in the control. Significantly higher amylase activity was observed in T-2 compared with that of T-1. There was no remarkable difference (P > 0.05) in amylase activity of T-2 compared with that of T-3, even though there was a tendency for increased activity. As for lipase activity of duodenum in broilers, assays showed no difference in all treatment groups. It showed that probiotic, B. coagulans NJ0516 administration in feed with a certain concentration displayed a growth promoting effect and increased the protease and amylase activities.  相似文献   

10.
The study was conducted to investigate the effects of mannanoligosaccharide (MOS) and probiotic supplementation on haematological and immunological parameters in turkeys. A total of 72, 15-day-old white hybrid converter turkey poults were used in this study. Poults were assigned into three groups, each group consisted of six poults and the trial was repeated four times. The control group was fed a basal diet without supplemented probiotic and MOS, and treatment groups were fed either 1 g/kg MOS or probiotic added diets. At the end of the 15-week treatment period, samples of blood were collected to determine immunological and haematological values. The comparison among the groups showed that both the probiotic and MOS supplementation resulted in significant increases (P < 0.05) in the serum IgG and IgM levels, and significant decreases (P < 0.05) in the peripheral blood T lymphocyte percentage compared with those of the control group. Mean serum IgG level (7.06 g/l) was significantly higher (P < 0.05) in poults supplemented with probiotic compared with MOS (6.76 g/l). It was observed that the probiotic supplementation caused statistically significant increases (P < 0.05) in the erythrocyte count, haemoglobin concentration and haematocrit values, but MOS supplementation did not have a significant effect (P > 0.05) on these parameters. Total leucocyte and differential leucocyte counts were not affected by dietary MOS and probiotic supplementation. These results show that MOS or probiotic may elevate IgG and IgM levels in turkey. The MOS and probiotic that enhance immunoglobulin levels will have a more positive effect on growth performance, production and turkeys' ability to resist disease.  相似文献   

11.
This trial evaluated the effects of various dietary calcium and nonphytate phosphorus (nPP) feeding regimens on the growth and bone integrity of Nicholas 700 toms from 2 to 19 wk of age. After a 2-wk common brooding period, 24 to 25 poults/pen were allocated to 8 pens/treatment. Crumbles were fed from 2 to 5 wk of age and pellets were fed from 5 to 19 wk of age in a 3-wk phase program. Dietary calcium was kept at a 1.8:1 ratio with nPP for all diets. Diet 1 (LOW) was formulated to provide NRC recommendations for each phase change, ending with 0.25% nPP from 17 to 19 wk of age. Diet 2 (MED) nPP levels averaged 0.06 percentage units higher than the LOW diet. Diet 3 (HIGH) averaged 0.10 percentage units higher nPP than the MED diet. Diet 4 (VHIGH) averaged 0.10 percentage units higher nPP than the HIGH diet. Body weight was decreased (P < 0.01) by the LOW diet compared with all other treatments throughout the trial. By 8 wk of age, BW was lower (P < 0.001) when the MED diet was fed compared with the HIGH and VHIGH diets. Feed:gain was worsened (P < 0.02) by the LOW diet, compared with the HIGH and VHIGH diets, throughout the entire trial. The incidences of leg problems and spontaneous bone fractures were increased (P = 0.001) when the LOW diet was fed compared with the other diets. The increase in litter phosphorus (P = 0.001) was directly proportional to increases in dietary nPP. The HIGH and VHIGH diets resulted in the best growth performance and skeletal integrity.  相似文献   

12.
Two pen trials and 2 field trials were conducted to determine whether a direct-fed microbial (DFM; Primalac) was effective in improving turkey productive performance. In the pen trials, typical turkey diets were formulated with and without Primalac. All feed was provided by a commercial feed mill. In trial 1, Large White male turkey poults were placed in 48 pens (18 birds/pen, 24 pens/treatment) on the day of hatch and were reared to 20 wk. In trial 2, Large White female turkey poults were placed in 48 pens (30 birds/pen, 24 pens/treatment) on the day of hatch and were reared to 18 wk. Cumulative FCR was significantly improved for birds fed DFM feed compared with birds fed control feed at 20 wk in trial 1 and at 8 wk in trial 2. Body weight was significantly greater for birds fed DFM feed compared with birds fed the control feed through 12 wk in both trials. In 2 field trials, 2 brooder houses and 4 grow-out houses were paired on each farm (4 brooder houses and 8 grow-out houses total). All birds received the same feed provided by the integrator. The DFM was provided in the water from placement to market in 1 brooder house and in the 2 matching grow-out houses. Breeder flocks were equally represented in both brooder houses within each trial. Approximately 12,000 male poults were placed in each brooder house and were transferred to 2 grow-out houses at 5 wk. Although no statistical analyses were computed for the field trials, there was a nominal improvement in performance associated with the DFM: mean livability was increased by 3.5%, mean BW was increased by 0.9 kg (2 lb), mean total weight removed from the farms was increased by 13,706 kg (30,153 lb), mean FCR was improved by 0.165, and cost of production was reduced by $0.0195/kg ($0.043/lb) of BW by the DFM. In conclusion, the DFM product (Primalac) used in these studies was effective in improving turkey live performance.  相似文献   

13.
An experimental study (15-wk-old ISA Brown pullets) was conducted to establish the efficacy of the essential oil of Eugenia caryophyllata against Salmonella enterica serovar Enteritidis. The trial was composed of 4 groups. Pullets in groups 3 and 4 were fed with a commercial compound feed, and pullets in groups 1 and 2 were fed with the same feed plus the aromatic product at the dose of 250 g/Tm. At 19 wk old, the pullets in groups 1 and 3 were infected individually with an inoculum of 3.2 ± 0.8 × 107 cfu of Salmonella enterica serovar Enteritidis/ pullet. During the postinoculation period, samples of feces and eggs were cultured, and pullets were killed 30 d postinoculation. The aromatic product containing eugenol seems to aid in the cleaning of the intestinal and systemic infections, and it also plays an important role in the control of Salmonella cross contamination in eggs.  相似文献   

14.
The present study was designed to evaluate the effect of individual or simultaneous application of 2 products, a competitive exclusion culture (CEC) or Megan Vac 1 (MV), for bioefficacy in reducing Salmonella Typhimurium (ST) cecal colonization in broiler chicks following experimental challenge. In experiment 1, CEC and MV were applied to day-of-hatch broiler chicks, and chicks were experimentally challenged with ST approximately 48 h later. In control chicks, ST was recovered at a level of 3.84 log10 cfu/g following direct plating of cecal contents, and 12 of 19 (63.15%) cultured individual ceca were positive following selective enrichment. In chicks receiving CEC by spray application on day of hatch, a numerical reduction in ST recovered from cecal contents (2.63 log10 cfu/g) and a significant reduction (P < 0.05) in recovery of ST from cultured ceca following selective enrichment (4 of 18, or 22.2%) was observed when compared with controls. Significant reductions in ST cecal colonization in chicks treated with MV alone were not observed in experiment 1. In experiment 2, chicks received day-of-hatch spray application of CEC alone, MV alone, or CEC and MV as a combined application immediately prior to or within 24 h of chick placement. When chicks were experimentally challenged with ST 48 h posthatch, significant reductions (P < 0.05) in cecal colonization by ST were observed with each experimental group when compared with nontreated controls. These data suggest that both commercially available products, alone or in combination, are efficacious in reducing cecal colonization in broiler chicks challenged with ST.  相似文献   

15.
In this study, broilers provided feed containing 109 cfu/t Bacillus subtilis PB6 in the finisher phase had a FCR similar to those on Zn bacitracin and significantly better than that of broilers provided nonmedicated feed with no added B. subtilis PB6 (P < 0.05). Over a 42-d period, broilers provided feed with B. subtilis PB6 had comparable feed intake and FCR as the antibiotic control. The counts of Lactobacillus species and Bifidobacterium species of broilers provided feed supplemented with B. subtilis PB6 were not significantly different from the number of these bacteria recovered from broilers provided feed supplemented with antibiotics. Numerically, up to 1- to 2-log10 reduction in the number of Clostridium species recovered was observed in broilers provided feed supplemented with B. subtilis PB6 when compared with both negative and antibiotic controls. In terms of immunological response, birds provided feed supplemented with B. subtilis PB6 had significantly heavier bursas, heterophils with higher in vitro phagoctyosis for Escherichia coli, and lower ileal E. coli populations, indicating a potentiating role of B. subtilis PB6 as a probiotic on the chicken innate immune system.  相似文献   

16.
A feeding trial was carried out with turkey poults, which were fed a diet containing 10(10) viable probiotic E. faecium NCIB 10415 cells/kg feed. Samples of the intestinal tract were analyzed for lactate, colony forming units of total anaerobic bacteria, lactic acid bacteria, enterobacteria and enterococci. Furthermore, metabolic activity of total eubacterial, lactobacilli and enterococci was recorded in selected RNA-extracts with specific ribosomal RNA oligonucleotide probes. Animals fed the probiotic diet showed continously increasing lactate concentrations throughout the sampling period up to day 42 of life. No correlation was found for colony forming units (cfu) of lactic acid bacteria, but metabolic activity of lactobacilli showed very close relation to continously increasing lactate concentrations. Throughout the feeding trial, enterococci in the control group continously increased to a maximum of 10(4) cfu/g wet weight, but 10-fold higher enterococci cfu were generally found in the treated group. However, rRNA content as measure for metabolic activity showed a drastic decline in both groups after high metabolic activities on day 7. This study shows that E. faecium NCIB 10415 (E. faecium SF68) stimulates other lactic acid bacteria in the small intestine, especially lactobacilli.  相似文献   

17.
Salmonella reduction in broilers from commercial broiler breeders vaccinated with live and killed Salmonella vaccines was evaluated. Broiler breeders were vaccinated with Poulvac ST live Salmonella Typhimurium vaccine at 1 d of age, and this was repeated at 2 and 6 wk of age. The breeders were then administered a killed autogenous oil emulsion adjuvanted vaccine containing Salmonella Kentucky, Salmonella Heidelberg, and Salmonella Hadar, at 10 and 18 wk of age. From the ages of 36 to 52 wk, eggs from the breeder flock were hatched, and progeny were challenged in 4 separate experiments at 1 d of age by oral gavage with 1 × 106 cfu/chick by either Salmonella Kentucky, Salmonella Heidelberg, Salmonella Hadar, or Salmonella Enteritidis, each containing resistance to naladixic acid at 32 μg/mL. At 17 to 21 d of age, the broilers were euthanized, and 1 side of the cecum was cultured for Salmonella, and the other side of the cecum was used for enumeration on positive samples. Recovered Salmonella was confirmed to be the challenge strain by O-antisera grouping. This study indicated a difference in Salmonella incidence and enumeration between the vaccinated and nonvaccinated breeder groups for certain species. When challenged with serotypes Salmonella Kentucky, Salmonella Hadar, and Salmonella Heidelberg, protection was noted with a reduction of 28, 17, and 11%, respectively, when compared with the control groups. However, protection was not seen when challenged with S. enteritidis. Under the conditions of this study, live and killed vaccination of commercial broiler breeders with Salmonella contributes protection to progeny when challenged at 1 d of age.  相似文献   

18.
Three commercial products, a partially defined chicken-origin competitive exclusion culture (Aviguard, 0.50 mL/chick) and 2 single-organism probiotic cultures (Saccharomyces cerevisiae, Levucell SC, 1 g/kg of feed, and Pediococcus acidilactici, Bactocell, 100 mg/kg of feed) were evaluated for their ability to reduce Salmonella in broilers and their effects on production performance. It was found that all the treatments significantly (P < 0.05) reduced Salmonella concentrations, as compared with the control, on the chicken, in the ceca, and on the chicken carcass. In addition, it was found that these treatments had no adverse effect on any of the production parameters that were measured. Finally, this study showed the importance of using these preharvest treatments as part of an integrated program to control Salmonella at the broiler farm.  相似文献   

19.
An experiment was conducted to investigate the effect of corn apparent metabolizable energy (AME) value, on broiler performance associated with geographical location (source), xylanase inclusion, and formulation. A 3 (corn source) × 2 (formulation; adjusted or non-adjusted value) × 2 (xylanase inclusion, 0 vs 16,000 BXU/kg) factorial randomized complete block desig study was conducted which included 10 replicates of 20 male broilers per replicate for a 42 d experiment. In the non-adjusted corn diets, each dietary treatment contained the same percentage of each corn source while the adjusted corn diets formulated based on a corn near-infrared (NIR) nutrient analysis and AME prediction equation (AB Vista, Marlborough, UK). In all cases, the predicted AME of the corns was lower than the NRC (1994) AME value, resulting in additional fat inclusion. The dietary program consisted of 3 dietary phases; starter (d 1 to 18), grower (d 19 to 33), and finisher (d 34 to 42) with growth performance monitored at feed changes. Xylanase increased (p < 0.05) starter feed consumption and d 18 body weight (BW) (2.1%), and an increase in BW (4.6%) was observed using the predicted AME values. Corn source continued to impact broiler performance throughout the remainder of the trial as corn source A consistently outperformed (p < 0.05) corn source C with increased BW and reduced mortality corrected FCR. Dietary adjustment with AME predicted values for each corn source consistently improved (p < 0.05) growth performance. Corn source A had the highest average BW with a 2.9% increase (p < 0.05) over corn source C. Early feed conversion rate (FCR) was improved (p < 0.05) with the predicted AME value diet-fed broilers, decreasing FCR by 3%. Multiple significant interactions were observed between the corn source and the adjustment method. For example, with d 42 FCR, using the predicted AME value adjustment had an impact of 9 and 10 points for corn source B and C, respectively, but only 2 for corn source A. This experiment demonstrates the impact of variable corn nutrient content and the potential improvement when using NIR technology for ingredient nutrient specifications.  相似文献   

20.
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.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号