Digestive Tract Of Broiler Chickens Research Articles

Impact of Trace Mineral Source and Phytase Supplementation on Prececal Phytate Degradation and Mineral Digestibility, Bone Mineralization, and Tissue Gene Expression in Broiler Chickens.

The objective of this study was to determine how different sources of Zn, Mn, and Cu in the feed without and with phytase affect prececal myo-inositol hexakisphosphate (InsP6) breakdown to myo-inositol (MI), prececal P digestibility, bone mineralization, and expression of mineral transporters in the jejunum of broiler chickens. A total of 896 male broiler chicks (Cobb 500) were distributed to 7 diets with 8 replicate pens (16 birds per floor pen). Experimental diets were fed from day 0 to 28. Diets were without or with phytase supplementation (0 or 750 FTU/kg) and were supplemented with three different trace mineral sources (TMS: sulfates, oxides, or chelates) containing 100mg/kg Zn, 100mg/kg Mn, and 125mg/kg Cu. Prececal InsP6 disappearance and P digestibility were affected by interaction (phytase × TMS: P ≤ 0.010). In diets without phytase supplementation, prececal InsP6 disappearance and P digestibility were greater (P ≤ 0.001) in birds fed chelated minerals than in birds fed sulfates or oxides. However, no differences were observed between TMS in diets with phytase supplementation. Ileal MI concentration was increased by exogenous phytase but differed depending on TMS (phytase × TMS: P ≤ 0.050). Tibia ash concentration as well as Zn and Mn concentration in tibia ash were increased by phytase supplementation (P < 0.010), but the Cu concentration in tibia ash was not (P > 0.050). Gene expression of the assayed mineral transporters in the jejunum was not affected by diet (P > 0.050), except for Zn transporter 5 (phytase × TMS: P = 0.024). In conclusion, the tested TMS had minor effects on endogenous phytate degradation in the digestive tract of broiler chickens. However, in phytase-supplemented diets, the choice of TMS was not relevant to phytate degradation under the conditions of this study.

Effects of hemp seed and flaxseed on enzyme activity in the broiler chicken digestive tract.

The activity of enzymes in the digestive tract is an important parameter for appropriate digestive tract function. Feed mixtures can be adjusted to support enzymatic activity in different parts of the digestive tract. Flaxseed and hemp seed are commodities and significant sources of nutrition, and their addition to feed could change enzymatic activity in the digestive tract and improve nutritional intake. The aim of this study was to determine the effects of flaxseed, hemp seed and a combination of both on basic enzymes in the polysaccharidase group, such as amylase, cellulase, pectinase, xylanase and inulinase; basic enzymes in the disaccharidase group, including maltase, invertase and lactase; proteinases and lipases in the digestive tract of broiler chickens. During the experiment, the control group was fed a diet without flaxseed or hemp seed. The diet of the second group contained 80g/kg flaxseed, the diet of the third group contained 40g/kg hemp seed, and the diets of the fourth to sixth groups contained 80 and 30g/kg, 80 and 40g/kg and 80 and 50g/kg flaxseed and hemp seed, respectively. Enzyme activity was found to depend on the location in the digestive tract and the composition of the feed mixture (P<0.05). Most enzymatic conversion occurs in the ileum, where the addition of flaxseed and hemp seed to the diet increased most enzyme activities, namely, amylase, cellulase, pectinase, xylanase, maltase, invertase, proteinase and lipase activities. The highest values of enzyme activity were found in groups IV-VI fed a combination of flaxseed and hempseed, especially in chickens fed diet VI (flaxseed and hemp seed at 80 and 50g/kg). Growth performance results confirmed the enzyme activity results, as the weights of the chickens increased after the addition of flaxseed and/or hemp seed. The findings have economic implications, suggesting that feeding a diet with a combination of flaxseed and hemp seed is beneficial.

Improving the performance and physical condition of the intestines of the Lohman MB202 broiler chicken intestine by using fermented local herbs

This research was conducted to find alternative antibiotics using local microorganisms which are expected to act as probiotics in the digestive tract. The local microorganisms used came from 3 types of herbs from 3 types of land. Crown flowers represent coastal land, ferns represent plantation land and lemongrass represents highland land. This study used an experimental method using a completely randomized design (CRD) with 5 treatments and each treatment had 4 replications (each replication contained 200 chickens). Treatment T1 water, T2 fermented crown flower, T3 fermented fern, and T4 fermented fragrant lemongrass each as much as 2 ml/liter of drinking water. The parameters measured were the performance and gut physical (village height and gut histology) of broiler chickens. Performance is body weight, weight gain, ration consumption, ration efficiency, performance index, and mortality. While the physical condition of the intestine is in the form of villi height and intestinal histology. The results showed that fern as a fermented herb significantly increased the performance index and improved the condition of the intestinal villi. However, the low mortality was significantly indicated by the fermented crown flowers. In conclusion, local fermented ferns have the potential as local microorganisms to replace the role of antibiotics because they can improve the performance and condition of the digestive tract of broiler chickens.

Effect of Supplementation of Different Levels of Urtica dioica Seeds to the Diet on the Immune Response and Microbial Composition of the Gastrointestinal Tract of Broiler Chickens.

This experiment was conducted in the poultry field of the Department of Animal Production, College of Agriculture, Al-Qasim Green University in order to assess the effect of adding different levels of Urtica dioica seeds to the diet on the immune response and microbial composition of the gastrointestinal tractof broiler chickens. This study was performed on 180 one-day-old unsexed broiler chickens (Ross 380) which were randomly divided into four treatments, with 45 birds per treatment and 3 replicates in each treatment (15 birds per replicate). The treatments were conducted as follows: First treatment (control) without the addition of Urtica dioica seeds to the diet, second treatment: the addition of 5g/kg Urtica dioica seeds, third treatment: the addition of 10g/kg Urtica dioica seeds, and treatment Fourth: the addition of 15g/kg Urtica dioica seeds. The experiment included the following traits: antibody titer against Newcastle disease, investigating sensitivity against Newcastle disease, the relative weight of bursa of Fabricius, bursa of Fabricius index, as well as estimating the total number of bacteria, Coliform bacteria, and Lactobacillus bacteria. The results indicated that the addition of Urtica dioica seeds led to significant improvement in cellular immunity (DHT) and antibody titer against Newcastle disease (ELISA), as well as significant improvement in the relative weight of bursa of Fabricius and bursa of Fabricius index, a significant decrease in the logarithmic number of total aerobic bacteria and Coliform bacteria, as well as a significant increase in the logarithmic number of Lactobacillus bacteria in the Duodenum contents for the small intestine and the Ceca, compared to the control treatment. Based on the obtained results, it can be concluded that the addition of Urtica dioica seeds to the diet can improve the immune traits and microbial compositions of the digestive tract of broiler chickens.

The influence of clove leave extract (Syzygium aromaticum) on growth performance and bacterial population of broiler chickens raised in stressful conditions of high stocking density

Broilers maintenance at high stocking density impacts uncomfortable conditions; this increases the potential for stress, reduces feed consumption, and reduces production performance and health in broiler chickens. This study aims to evaluate the effect of clove leaf extract on growth performance and microbial population in the digestive tract of broiler chickens reared at high density. From the eighth day, five treatment groups, T0 (negative control with a typical density of 10 birds/m2), T1 (positive control with a high density of 16 birds/m2), T2, T3, and T4 with a high density of 16 birds/m2, were randomly assigned from 444 broilers (bodyweight of 129.78±0.75 g) with six repetitions each on the eighth day. The feed includes clove leave extract as much as 0.5, 0.75, and 1 ml/kg for T2, T3, and T4, respectively. The weight gain, feed intake, and feed conversion ratio were tracked weekly. One chicken from each replicate was taken randomly, slaughtered, and feathered on day 35. The digesta was taken from the ileum and cecum to measure the intestinal bacterial population and put into a sterile container. Digesta from the duodenum, jejunum, ileum, and cecum were also collected to determine pH levels. MRS agar was used to determine the amount of LAB in the digesta. The findings revealed that giving clove leaf extract of feed to broiler chickens kept at high stocking density could higher body weight gain (P < 0.05), higher feed consumption (P < 0.05), decreased the pH of the ileum and cecum (P < 0.05), increased lactic acid bacteria and decreased coliform bacteria in the ileum and cecum (P < 0.05).

Effects of calcium level and source, formic acid, and phytase on phytate degradation and the microbiota in the digestive tract of broiler chickens

BackgroundDiet acidification, dietary calcium (Ca) level, and phytase supplementation are known influences on the microbial community in the digestive tract and on phosphorus (P) utilization of broiler chickens. Effects of dietary factors and microbiota on P utilization may be linked because microorganisms produce enzymes that release P from phytate (InsP6), the main source of P in plant feedstuffs. This study aimed to detect linkages between microbiota and InsP6 degradation by acidifying diets (i.e., replacing Ca carbonate (CaCO3) by Ca formate or adding formic acid to CaCO3-containing diets), varying Ca levels, and supplementing phytase in a three-factorial design. We investigated i) the microbial community and pH in the digestive tract, ii) prececal (pc) P and Ca digestibility, and iii) InsP6 degradation.ResultsAll factors under investigation influenced digesta pH and the microbiota composition. Predicted functionality and relative abundance of microorganisms indicated that diets influenced the potential contribution of the microbiota on InsP degradation. Values of InsP6 degradation and relative abundance of the strains Lactobacillus johnsonii and Lactobacillus reuteri were correlated. Phytase supplementation increased pc InsP6 disappearance, with differences between Ca levels, and influenced concentrations of lower inositol phosphate isomers in the digestive tract. Formic acid supplementation increased pc InsP6 degradation to myo-inositol. Replacing CaCO3 by Ca-formate and the high level of these Ca sources reduced pc InsP6 disappearance, except when the combination of CaCO3 + formic acid was used. Supplementing phytase to CaCO3 + formic acid led to the highest InsP6 disappearance (52%) in the crop and increased myo-inositol concentration in the ileum digesta. Supplementing phytase leveled the effect of high Ca content on pc InsP6 disappearance.ConclusionsThe results point towards a contribution of changing microbial community on InsP6 degradation in the crop and up to the terminal ileum. This is indicated by relationships between InsP6 degradation and relative abundance of phosphatase-producing strains. Functional predictions supported influences of microbiota on InsP6 degradation. The extent of such effects remains to be clarified. InsP6 degradation may also be influenced by variation of pH caused by dietary concentration and solubility of the Ca in the feed.

Utilization of infertile egg powder in ration improves the digestive tract development of broiler chickens

Infertile egg powder (IEP) is a potential feedstuff with high nutrient content. This experiment investigated the effect of IEP utilization in the ration on digestive tract development of broiler chickens. In total, 196 one-day-old male broilers were distributed into four dietary treatments with 7 replicates of 7 birds each. The treatments comprised a basal diet (T0), 96% basal diet + 4% IEP (T1), 94% basal diet + 6% IEP (T2), and 92% basal diet + 8% IEP (T3). The weight and length of the digestive tract were measured at the end of feeding trial to observe their development. Analysis of variance was applied to analyze the effect of treatments, while Duncan’s Multiple Range Test was applied to compare the mean of each treatment. The results indicated that feeding with IEP (T1, T2, and T3 groups) generated the longer duodenum, jejunum, ileum and whole small intestine compared with feeding without IEP (T0, P<0.05), with the highest magnitude was observed for T3. Accordingly, IEP improved the weight of small intestine (P<0.05). In line with this, the IEP groups had heavier gizzard and liver than non-IEP groups. It can be concluded that IEP improves the development of digestive tract of broiler chickens.

The Effect of Antibiotic Growth Promoters (AGP) on Antibiotic Resistance and the Digestive System of Broiler Chicken in Sleman, Yogyakarta

Chicken is a major source of animal protein consumption in Indonesia. The problem facing the poultry industry is the incidence of resistance which increases mortality of the chicken production. One of the causes of resistance case is the use of antibiotics in feed additives. The public understanding about the effects of the use of antibiotic growth promoters (AGP) in chickens in antibiotic resistance and the digestive tract of chicken needs to be done to avoid the impact on economic losses and health problems. This study aims to provide an understanding of the effects of the use of antibiotic growth promoters (AGP) on antibiotic resistance and the digestive tract of broiler chickens. This study was carried out at a broiler chicken farm in Sleman, Yogyakarta. Based on the histopathological result of the digestive tract of chickens that were given antibiotics as AGP, there was no inflammation occurs, but the administration of antibiotics caused antibiotic resistance in various type of antibiotics including tetracycline (90% resistance), streptomycin (60% resistance), amoxicillin (50% resistance), erythromycin (80% resistance), and no resistance for gentamycin.

Impact of coccidiostat and phytase supplementation on gut microbiota composition and phytate degradation in broiler chickens

BackgroundThere is good evidence for a substantial endogenous phytase activity originating from the epithelial tissue or the microbiota resident in the digestive tract of broiler chickens. However, ionophore coccidiostats, which are frequently used as feed additives in broiler diets to prevent coccidiosis, might affect the bacterial composition and the abundance of phytase producers in the gastrointestinal tract. The aim of the present study was to investigate whether supplementation of a frequently used mixture of the coccidiostats Narasin and Nicarbazin alone or together with a phytase affects microbiota composition of the digestive tract of broiler chickens, characteristics of phytate breakdown in crop and terminal ileum, and precaecal phosphorus and crude protein digestibility.ResultsLarge differences in the microbial composition and diversity were detected between the treatments with and without coccidiostat supplementation. Disappearance of myo-inositol 1,2,3,4,5,6-hexakis(dihydrogen phosphate) (InsP6) in the digestive tract, precaecal P digestibility, inorganic P in blood serum, and the concentration of inositol phosphate isomers in the crop and ileum digesta were significantly affected by phytase supplementation, but not by coccidiostat supplementation. Crude protein digestibility was increased by coccidiostat supplementation when more phosphate was available. Neither microbial abundance and diversity nor any other trait measured at the end of the experiment was affected by coccidiostat when it was only supplemented from day 1 to 10 of age.ConclusionsThe coccidiostats used herein had large effects on overall microbiota composition of the digestive tract. The coccidiostats did not seem to affect endogenous or exogenous phytase activity up to the terminal ileum of broiler chickens. The effects of phytase on growth, phosphorus digestibility, and myo-inositol release were not altered by the presence of the coccidiostats. The effects of phytase and coccidiostats on nutrient digestibility can be of significant relevance for phosphorus and protein-reduced feeding concepts if confirmed in further experiments.

7. Effect of Soya Wastes Probiotic and Palm Kernel Addition Fermented by Aspergillus niger to the Cellulase Activity in Broilers Digestive Tract

This study aimed to determine the cellulase activity in broilers digestive tract after the treatment of soya wastes and palm kernel fermented by A.niger (AKBIS Prob) in the ration. This study used a complete randomized factorial design, which consists of two factors, namely the AKBIS Prob composition factor and the duration of AKBIS Prob. Twenty four broilers were divided into four groups by randomized and three replications of each. The feed supplement combinations were P0 (commercial), P1 (commercial and AKBIS Prob 2%), P2 (commercial and AKBIS Prob 4%), and P3 (commercial and AKBIS Prob 6%). The intestine preparation was taken at the 22 and 36 days to extraction and detection the cellulase activity concentration. Data were analyzed using variance analysis of factorial patterns. AKBIS Prob 2,4 and 6% was no effect (P 0.05) to the cellulase activity in the small and large intestine, while the treatment duration was significant (P0,05) in the small intestine but neither in the large intestine (P0,05) to the cellulase activity. The addition of AKBIS Prob 2.4 and 6% had no effect (P 0.05) on the concentration of cellulase activity in the small intestine and large intestine, while the duration the treatment was very significant (P 0.05) in the small intestine and neither in the large intestine (P 0.05) on the concentration of cellulase activity. The AKBIS administration in the ration for 22 days can increase the activity and concentration of cellulase activity in the small intestine of the digestive tract of broiler chickens.

Interactive effects of phosphorus, calcium, and phytase supplements on products of phytate degradation in the digestive tract of broiler chickens

This study aimed to distinguish between the single and interactive effects of phosphorus (P), calcium (Ca), and phytase on products of phytate degradation, including the disappearance of myo-inositol (MI), P, Ca, and amino acids (AA) in different segments of the digestive tract in broiler chickens. Additionally, all dephosphorylation steps from myo-inositol 1,2,3,4,5,6-hexakis (dihydrogen phosphate) (InsP6) to MI were investigated in the digesta of the terminal ileum. Unsexed Ross 308 broiler chickens were allocated to 56 pens with 19 birds per pen, and assigned to one of 8 dietary treatments. The dietary treatments included diets without (P−, 4.1 g/kg DM) or with (P+, 6.9 g/kg DM) monosodium phosphate supplementation, without (Ca−, 6.2 g/kg DM) or with (Ca+, 10.3 g/kg DM) additional fine limestone supplementation, and without or with 1,500 FTU phytase/kg feed in a factorial design. Adding Ca or P had no effect on InsP6 disappearance in the crop when phytase was added. InsP6 disappearance up to the terminal ileum (P−Ca− 56%) was decreased in P+Ca− (40%), and even more so in P+Ca+ (21%), when no phytase was added. Adding phytase removed all effects of P and Ca (77 to 87%); however, P+Ca+ increased the concentrations of lower InsP esters and reduced free MI in the ileum, even in the presence of phytase. These results indicate that mineral supplements, especially P and Ca combined, reduce the efficacy of endogenous microbial or epithelial phosphatases. Supplementation with phytase increased, while supplementation with Ca decreased the concentration of MI in all segments of the digestive tract and in blood plasma, demonstrating the ability of broilers to fully degrade phytate and absorb released MI. While AA disappearance was not affected by P or Ca, or an interaction among P, Ca, and phytase, it increased with the addition of phytase by 2 to 6%. This demonstrates the potential of the phytase used to increase AA digestibility, likely independent of P and Ca supply.

Influence of oregano added to diets on performance, selected organs as well as morphometric traits and pH of digestive tract of broiler chickens

The aim of the study was to evaluate the effect of the addition of dried oregano from different regions of the world to diets on the production results, selected organs, as well as the morphometric characteristics and pH of the gastrointestinal tract of broiler chickens. The research feedstuff was dried oregano from Poland, Turkey and Egypt and diets containing these herbs. The oregano from Poland, Turkey and Egypt was added to a wheat-corn-soybean diet in an amount of 2%. The experiment was carried out on 168 broilers Ross 308, 84 males and 84 females, randomly divided into 4 groups of 42 birds each. In this experiment, four diets for the starter period (from 1 to 21 days of age) and four for the grower period (from 22 to 42 days of age) were prepared. The control group (K) were fed a wheat-corn-soybean diet without oregano, whereas chickens from the experimental groups were fed diets with oregano from Poland (OP group), Turkey (OT group) or Egypt (OE group). During the experiment, the body weight at 1, 2, and 42 days of age, feed consumption and mortality were recorded. At 42 days of age, after 14 hours of fasting, the birds were killed and from the body of 32 chickens (8 chickens from each group) the digestive tract, heart, liver, pancreas and spleen were prepared and weighed. The gastrointestinal tract was divided into sections, and their weight and length were measured. Then, in particular segments of the gastrointestinal tract, pH values were determined. The body weight of chickens determined at 21 and 42 days of age were not significantly different between the groups. Significant differences between the groups were noted in feed efficiency during the grower period. The diet containing oregano from Turkey was utilized significantly better than the control diet. Significant differences in the pH of the glandular stomach and caecum were found. Compared with pH in the control group, pH in the glandular stomachs of chickens fed diets containing dried oregano from Egypt was significantly decreased, whereas pH in the caecum of chickens from the OT group was increased. In comparison with the control group, chickens from the groups fed diets containing oregano (except the OP group) had a significantly shorter ileum and larger intestines, and chickens fed a diet with oregano from Turkey had a smaller spleen and gizzard. The results obtained show that the chemical composition of dried oregano from different regions was differential. The addition of 2% of dried oregano to the wheat-corn-soybean diet had no significant influence on the body weight of chickens, but decreased their mortality. Oregano from Turkey added to the wheat-corn-soybean diet improved the feed efficiency in the second period of rearing. These results show that oregano may be a potentially effective supplement for broiler chickens, and the most effective was the oregano from Turkey....

Insights into Broilers' Gut Microbiota Fed with Phosphorus, Calcium, and Phytase Supplemented Diets.

Phytase supplementation in broiler diets is a common practice to improve phosphorus (P) availability and to reduce P loss by excretion. An enhanced P availability, and its concomitant supplementation with calcium (Ca), can affect the structure of the microbial community in the digestive tract of broiler chickens. Here, we aim to distinguish the effects of mineral P, Ca, and phytase on the composition of microbial communities present in the content and the mucosa layer of the gastrointestinal tract (GIT) of broiler chickens.Significant differences were observed between digesta and mucosa samples for the GIT sections studied (p = 0.001). The analyses of 56 individual birds showed a high microbial composition variability within the replicates of the same diet. The average similarity within replicates of digesta and mucosa samples across all diets ranged from 29 to 82% in crop, 19–49% in ileum, and 17–39% in caeca. Broilers fed with a diet only supplemented with Ca had the lowest body weight gain and feed conversion values while diets supplemented with P showed the best performance results. An effect of each diet on crop mucosa samples was observed, however, similar results were not obtained from digesta samples. Microbial communities colonizing the ileum mucosa samples were affected by P supplementation. Caeca-derived samples showed the highest microbial diversity when compared to the other GIT sections and the most prominent phylotypes were related to genus Faecalibacterium and Pseudoflavonifractor, known for their influence on gut health and as butyrate producers. Lower microbial diversity in crop digesta was linked to lower growth performance of birds fed with a diet only supplemented with Ca. Each diet affected microbial communities within individual sections, however, no diet showed a comprehensive effect across all GIT sections, which can primarily be attributed to the great variability among replicates. The substantial community differences between digesta and mucosa derived samples indicate that both habitats have to be considered when the influence of diet on the gut microbiota, broiler growth performance, and animal health is investigated.

Effects of cashew nut shell liquid (CNSL) on the performance of broiler chickens

The effects of cashew nut shell liquid (CNSL) on growth performance, carcass yield, relative weight of internal organs and microbiology of digestive tract of broiler chickens were investigated. Five hundred and forty male broiler chicks at one day of age were arranged in a completely randomized design with six treatments and six repetitions with 15 broiler chicks each. The treatments were: control (T1 - without growth promoter virginiamycin and CNSL); inclusion levels of 0.10mL (T2), 0.20mL (T3), 0.30mL (T4) and 0.40mL (T5) of CNSL/kg of feed; and commercial promoter virginiamycin (T6). At 21 and 40 days of age, body weight, feed intake, feed conversion and viability of birds were similar in all treatments. Carcass yield was higher in the treatment with the growth promoter when compared to the control treatment. There was a linear increase in carcass yield when the level of CNSL was increased in the diet. The relative weight of the intestine was lower in the treatment containing virginiamycin when compared to the treatment without the inclusion of additives. The relative weight of the intestines decreased when the levels of inclusion of CNSL were increased. There was a gradual reduction of Escherichia coli concentration reaching the lowest number on the CNSL level of 0.30mL/kg. It was concluded that CNSL showed similar performance and slaughter yield as the growth promoter and reduced the concentration of Escherichia coli in the intestinal contents.

Effects of dietary lipids and Clostridium butyricum on the performance and the digestive tract of broiler chickens

The effects of two sources of dietary lipids and supplementation of Clostridium butyricum on performance and intestinal metabolism of broilers were investigated. In a 2 × 2 factorial arrangement, 168 one-day-old broiler chicks were divided into four treatment groups, and fed four diets with two lipid sources (soya bean oil or fish oil, at 25 g/kg and 30 g/kg in starter and grower diets respectively), and without or with supplementation of C. butyricum (1 · 109 colony forming units per kg diet). C. butyricum had no effect on broiler performance. At 20 and 40 d of age, the pH of caecal digesta and the relative length of caecum were decreased after supplementation of C. butyricum (p < 0.05). After this treatment, the activity of alkaline phosphatase was increased in jejunal mucosa at 40 d of age (p < 0.01). Furthermore, there were increases in populations of lactic acid bacteria and the concentrations of acetic acid, n-butyric acid, n-valeric acid and total short chain fatty acids in caecal digesta of birds fed C. butyricum (p < 0.05). A significant interaction between lipid source and C. butyricum was found in the pH of caecal digesta at 20 d of age (p < 0.01). The results of the present study indicated that dietary supplementation of C. butyricum maybe a benefit for gut health of broiler chickens.

A small variation in diet influences the Lactobacillus strain composition in the crop of broiler chickens

Feed composition has the potential to influence the activities of bacteria that colonize the digestive tract of broiler chickens with important consequences for animal health, well being, and food safety. In this study, the gut microbiota of two groups of broiler chickens raised in immediate vicinity but fed either a standard corn/soybean meal ration (corn–soy, CS) or a ration high in wheat middlings (high wheat, HW) was characterized. The findings revealed that this small variation in feed composition did not influence the distribution of microbial species present in the microbial community throughout the digestive tract. However, diet variation markedly influenced the Lactobacillus strain composition in the crop. Most striking, the dominant type in birds on the CS diet ( Lactobacillus agilis type R5), which comprised 25% of the isolates, was not detected in birds fed the HW diet. The latter birds harbored a different strain of L. agilis (type R1) in a significantly higher ratio than birds on the CS diet. Several other strains were also specific to the particular diet. In conclusion, this study showed that a small variation in the composition of chicken feed that does not result in detectable differences in species composition can still have an impact on which microbial strains become dominant in the digestive tract. This finding has relevance in the application of probiotics and other direct-fed microbials in poultry husbandry.

Effect of dietary Phytase and NSP-degrading enzymes in diets containing rape seed meal on broiler carcass characteristics

In comparison to the 44% crude protein of soybean meal (SBM), the protein content of rapeseed meal (RSM) is about 35-40% and has a physiologically suitable amino acid profile for animal nutrition. However, RSM contains nutritionally unfavourable substances such as glucosinolates, sinapin, tannin, phytate and non starch polysaccharides (Kocher et al., 2000). Enzymes have potential to improve the nutrients availability of diets containing antinutritional factorst. NSPs include cellulose, B-glucans, arabinoxylans, and pectins that may increase viscosity of digesta and cause a decrease in nutrient digestibility and performance of broiler chickens. Phytase from digestive secretions, some feed ingredients, resident bacteria and exogenous microorganisms is present in the digestive tract of broiler chickens (Kornegay, 2001), but its efficiency at a practical level is very low. It accepted that broilers lack sufficient levels of phytase activity to effectively hydrolyse the phytate molecule. Phytate-bound P is not well digested, so inorganic P is added to broiler diets that increases feed costs (Lescoat et al., 2005). The purpose of this study was to investigate the replacement value of SBM with locally grown RSM and two enzymes (NSP-degrading and phytase) on the weight of carcass, some organs, and amount of blood-Ca and P of broiler chickens.

Effect of dietary Phytase and NSP-degrading enzymes in diets containing rape seed meal on broiler performance

In comparison to 44% crude protein of soybean meal (SBM), the protein content of rapeseed meal (RSM) is about 35-40% and has a physiologically suitable amino acid combination in animal nutrition, but RSM contains nutritionally unfavourable substances such as glucosinolates, sinapin, tannin, phytate and non starch polysaccharides (NSP) (Kocher et al., 2000). Enzymes have the potential to be used in diets contain antinutritional factors that hinder nutrient availability. NSPs include cellulose, B-glucans, arabinoxylans, and pectins that may increase viscosity of digesta and cause a decrease in nutrient digestibility and performance of broiler chickens. Phytase activity from digestive secretions, some feed ingredients, resident bacteria, exogenous microorganisms, or both resident bacteria and exogenous microorganisms is present in the digestive tract of broiler chickens (Kornegay, 2001), but its efficiency at a practical level is very low. It is accepted that broilers lack sufficient levels of phytase activity to effectively hydrolyse the phytate molecule. Phytate-bound P is not well digested, so inorganic P is added to broiler diets that increased feed costs (Lescoat et al., 2005). The purpose of this study was to investigate the replacement value of SBM with locally grown RSM and two types of enzymes (NSP-degrading and phytase) on performance of broiler chickens.

The effects of fructo-oligosaccharides or whole wheat on the performance and digestive tract of broiler chickens

1. The objective of this experiment was to study two feeding methods, which could potentially act on the gut microflora, the structure and/or the function of the digestive tract and thereby improve the performance of broilers. 2. Four dietary treatments were studied: a negative control (wheat based) with no additives (C), a positive control with 0·01 g/kg avilamycin (AV), a treatment with 0·6 g/kg fructo-oligosaccharides (FOS) and a treatment with the same composition as treatment C but in which a part or all (400 g/kg) of the wheat was given as whole wheat and a concentrate supplement (WW). The measurements were: the performance from 0 to 6 weeks, the bacterial counts at 3 and 6 weeks, the digestive tract morphology and the activity of some intestinal enzymes at 3 weeks. 3. The birds given AV had better daily live weight gain (DLWG) and feed conversion ratio (FCR) compared to treatment C. The birds given FOS had a lower feed intake and a lower DLWG than the birds on treatment C but their FCR was significantly improved. WW resulted in a numerically lower feed intake and a significantly lower DLWG than treatment C. With AV, the number of aerobic mesophilic bacteria in the caeca was reduced at 3 weeks. With WW, gizzard and pancreas weights were greater and the surfaces of the ileal crypts were larger. An increased activity of leucine aminopeptidase (LAP) in the duodenum was found for treatments AV, FOS and WW. 4. In conclusion, in this study, treatments WW and FOS reduced DLWG, which may have been due to a lower feed intake during the whole period. With WW, the FCR was not affected, maybe because of both positive and negative effects on digestive tract (higher gizzard and pancreas development and LAP activity; larger crypts). However, FOS improved FCR, which may be partly explained by the higher LAP activity.

Effects of whole wheat feeding on the development of the digestive tract of broiler chickens

The objective of the current study was to investigate the impact of including whole wheat in broiler diets on the development of the digestive tract. Chickens were fed a standard feed containing 400 g ground wheat/kg or the same diet with a part of the wheat given separately as whole grains that increased progressively from 200 g/kg at 8 d to 400 g/kg at 22 d. Every week, from 16 to 44 d, growth performance, modifications of the size of the digestive tract organs and intestinal enzyme activities were investigated. Morphology of villi and crypts in the small intestinal segments (duodenum, jejunum, ileum) were analyzed at 23 and 44 d. Microbacterial counts were performed in jejunal, ileal and caecal contents weekly from 16 to 44 d. During the adaptation period from 8 to 15 d, the birds fed the whole wheat diet had lower feed intake and lower weight gain. Thereafter, they showed improved growth performance so that by the end of the experiment, they had higher body weight compared to the standard-fed birds, 2430 ± 29 versus 2331 ± 36 g. Higher relative weights of gizzard (+26%) and pancreas (+12%) were observed from 16 to 44 d for whole wheat-fed birds compared to standard-fed birds. No differences in relative size of the different intestinal segments were observed, except that the jejunum was shorter. Increased villus to crypt length and surface ratios were observed at 23 d in the duodenum of whole wheat-fed birds, with no differences in morphometry between groups thereafter. Alkaline phosphatase activity was higher from 16 to 44 d in the duodenum and jejunum of whole wheat-fed birds. However, the activities of the digestive enzymes, leucine aminopeptidase and maltase, were similar between the two diets in the measured intestinal segments. A lower number of facultative anaerobic bacteria was found in the ileum of the whole wheat-fed birds, with no differences between treatments for Escherichia coli and for Lactobacillus counts. In the jejunum and the caeca, no differences in microflora counts were observed. The present results showed that feeding whole grains to broilers led mainly to modifications in the upper part of the digestive tract (gizzard, pancreas) and had little influence on the small and large intestine.