A Preliminary Study of Chemically Preserved and High-Moisture Whole Maize (Zea mays L.) Usage in Pekin Duck Nutrition: Effect on Growth Performance and Selected Internal Organ Traits

Simple Summary

Harvested maize grains characterized by high moisture require the use of additional preservation processes to secure against the microbiota. The most commonly used practice is heat-drying, which is energy- and cost-consuming, as well as environmentally unfriendly. Thus, there is a need to omit these harmful techniques and evaluate the usage of wet maize in animal nutrition. The present study aimed to investigate the effect of the chemically preserved, high-moisture whole maize grain addition in Pekin duck nutrition on their growth performance and selected internal organ and gastrointestinal tract measurements and digesta pH values. The results of the experiment clearly showed that there is a possibility to partially replace commonly used heat-dry maize with the preserved whole-grain form without an adverse effect on the birds’ performances and selected organ morphometrical parameters. However, due to surprising changes in the pH values in the gizzard and caeca, further investigations, including microbiota analyses, are recommended.

Abstract

This study aimed to investigate the effect of chemically preserved, high-moisture whole maize grain addition in Pekin duck diets on their growth performance and selected internal organ and gastrointestinal tract measurements and digesta pH values. A total of 300 29-d-old male Pekin ducks were randomly distributed into three dietary treatments using five replicate pens per group and 20 birds per pen. The following treatment groups were applied: CON—basal diet, 5HM—5% of high-moisture, chemically preserved whole maize (HM) inclusion, and 10HM—10% of HM addition. The experiment lasted 21 d. The implementation of 5HM or 10HM did not affect (p > 0.05) the growth performance parameters, selected internal organ weights, and the gastrointestinal tract segment weights and lengths. However, significant changes in terms of the gizzard (p = 0.005), ileum (p = 0.030), and caecal (p < 0.001) digesta pH were observed, especially in the case of the 10HM group, which exhibited the greatest increase in pH in the gizzard and caecal digesta and decrease in the ileal digesta pH. The implementation of whole wet maize may be used in waterfowl diets from 29 d of age. Additionally, chemical preservation can efficiently reduce the cost of maize preparation in duck nutrition.

Functioning of the Intestinal Ecosystem: From New Technologies in Microbial Research to Practical Poultry Feeding – A Review

Unlike classical microbiology which focuses on bacteria capable of growing in vitro, metagenomics is a study of genetic information originating from microflora which aims to characterise the microbiome, namely the common genome of bacteria, archaea, fungi, protozoa and viruses living in the host. Metagenomics relies on next-generation sequencing (NGS), a large-scale sequencing technique which allows millions of sequential reactions to be carried out in parallel to decode entire communities of microorganisms. Metagenomic analyses support taxonomic analyses (involving gene fragments encoding ribosomal RNAs 5S and 16S in bacteria) or functional analyses for identifying genes encoding proteins that participate in the regulation of metabolic pathways in the body. New metagenomics technologies expand our knowledge of the phylogenetic structure of microflora in the gastrointestinal tract of poultry, and they support the identification of previously unknown groups of microbiota, mainly those occurring in small numbers. Next-generation sequencing also provides indirect information about the quantitative structure of the genes of gut microorganisms, but microbial activity and changes in the proportions of microbial metabolites that affect the host’s intestinal integrity and metabolism remain insufficiently investigated. Therefore, research studies are undertaken to investigate the proportions of the key microbial metabolites in the intestinal contents of poultry relative to changes in the population size of the most important bacterial groups, including those determined by cheaper techniques.

Colonic and systemic effects of extruded whole-grain sorghum consumption in growing Wistar rats

Colonic effects of extruded whole-grain sorghum diets were evaluated using a model of growing rats. In all, twenty-four male Wistar rats were fed control (C), extruded white sorghum (EWS) or red sorghum (ERS). Consumption of sorghum diets showed satiety properties, with reduction of caecal pH, and lower activity ofβ-glucosidase andβ-glucuronidase enzymes. Decreased copper zinc superoxide dismutase and manganese superoxide dismutase and increased catalase and glutathione peroxidase levels were observed in colonic mucosa. The induction of antioxidant enzymes occurred through the activation of the nuclear factor erythroid 2-related factor 2 protein and its subsequent translocation into the nucleus. ERS was able to decrease the proliferation of proximal mucosa of colon, demonstrating a possible effect against colorectal tumourigenesis. EWS increased proliferation and also apoptosis, ensuring the re-establishment of homoeostasis of the colonic mucosa. No antioxidant systemic effect (serum or hepatic level) was observed. It is likely that despite the extrusion the low bioavailability of the phenolic compounds of sorghum diets caused them to exert mainly acute effects at the colon level. Extruded whole-grain sorghum is a good functional ingredient that might be promising in dietary prevention of intestinal diseases.

Influence of partial replacement of ground wheat with whole wheat and exogenous enzyme supplementation on growth performance, nutrient digestibility and energy utilization in young broilers

This study investigated the influence of pre-pelleting inclusion of whole wheat (WW) and exogenous enzyme supplementation on growth performance, coefficient of apparent ileal nutrient digestibility (CAID) and apparent metabolizable energy (AME) in broilers fed wheat-based pelleted diets. A 2 × 3 factorial arrangement of treatments was used with two methods of wheat inclusion [622 g/kg ground wheat (GW) and 250 g/kg WW replaced GW (wt/wt) pre-pelleting (PWW)] and three enzymes (xylanase, phytase and xylanase plus phytase). A total of 288, one-day-old male broilers (Ross 308) were individually weighed and allocated to 36 cages (8 broilers/cage), and the cages were randomly assigned to the six dietary treatments. Birds fed PWW diets gained more (p < 0.05) weight than those fed GW diets. There was no effect (p > 0.05) of WW inclusion on feed intake (FI). Phytase alone increased (p < 0.05) FI compared to xylanase or the combination. Whole wheat inclusion increased (p < 0.05) the gain-to-feed ratio (G:F). Feeding xylanase plus phytase and phytase-added diets resulted in the greatest and lowest G:F, respectively, with xylanase supplemented diets being intermediate. Birds fed PWW diets had greater (p < 0.05) relative gizzard weights than those fed GW diets. There was no effect (p > 0.05) of WW inclusion on the CAID of nitrogen (N), starch and fat. Combination of xylanase and phytase resulted in greater (p < 0.05) digestibility of N, starch and fat than that of individual additions. Feeding PWW diets resulted in greater (p < 0.05) AME values than GW diets. Combination of xylanase and phytase increased (p < 0.05) the AME compared to the diets with individual additions of xylanase or phytase. The current results suggest that the influence of pre-pelleting WW inclusion and exogenous enzymes on nutrient digestibility and broiler performance is not additive.

Effects of the Physical Form of Diet on the Outcome of an Artificial Salmonella Infection in Broilers

To prove the hypothesis that the physical form of diet affects the outcome of an artificial infection with Salmonella Enteritidis in broilers, 7-day-old birds were allotted to one of four groups and fed botanically, and nearly also chemically identical diets, differing in grinding and further compaction. In total, two birds from each group (age 14 days) were administered on average 1.06 x 10(8) colony-forming units (CFU) of Salmonella Enteritidis directly into the crop by gavage and immediately put back as "seeder birds" into their respective groups. The salmonella status of each bird was analyzed by cloacal swabs, and at postmortem examination, cecal content and liver tissue samples were taken. Shedding (measured by cloacal swabs) was reduced significantly (P < 0.05) in groups offered the coarsely ground and pelleted diet and the diet including whole wheat compared with the groups fed the finely ground and pelleted and the coarsely ground and extruded diet. Nevertheless, only broilers fed the diet containing whole wheat showed a significantly (P < 0.05) lower frequency of Salmonella Enteritidis isolation in the cecal content and liver tissue. This diet was characterized by the highest percentage of particles > 2 mm. In this study the physical form of diet affected the outcome of an artificial infection with Salmonella Enteritidis significantly.

Effect of lactulose supplementation on growth performance, intestinal histomorphology, cecal microbial population, and short-chain fatty acid composition of broiler chickens

This study investigated the effects of dietary lactulose supplementation on broiler growth performance, intestinal histomorphology, cecal microflora, and cecal short-chain fatty acid (SCFA) concentrations. A total of 245 one-day-old male broiler chickens were randomly assigned to 5 different treatments, with 7 replicates including 7 birds each. The birds received the same basal diet based on corn--soybean meal, and lactulose was included in the diet at 0, 0.2, 0.4, 0.6, or 0.8% at the expense of corn and/or soybean meal. The body weight gain (linear, P=0.027) and feed conversion (linear, P=0.003) from 0 to 21 d showed significant improvement as dietary lactulose was increased from 0.2 to 0.8%. However, dietary lactulose did not affect broiler performance at the end of the experiment (42 d). Furthermore, intestinal measurements and the goblet cell count of broilers fed a lactulose-containing diet differed from those of birds fed a diet that did not contain lactulose. In addition, a significant quadratic response in the Lactobacillus count (P≤0.001) was observed at 42 d on increasing the level of lactulose. The cecal coliform bacterial population was not affected by the dietary treatments. Supplementation with lactulose significantly increased the concentrations of acetate, propionate, butyrate, and total SCFA measured on d 7 and d 42. In conclusion, inclusion of lactulose in the diet can enhance broiler performance and intestinal morphology by selectively stimulating intestinal microflora and increasing cecal SCFA concentrations.