(Bio)Technological processing of poultry and pig feed: Impact on the composition, digestibility, anti-nutritional factors and hygiene

In vitro evaluation of the application of an optimized xylanase cocktail for improved monogastric feed digestibility

Xylanases from glycoside hydrolase (GH) families 10 and 11 are common feed additives for broiler chicken diets due to their catalytic activity on the nonstarch polysaccharide xylan. This study investigated the potential of an optimized binary GH10 and GH11 xylanase cocktail to mitigate the antinutritional effects of xylan on the digestibility of locally sourced chicken feed. Immunofluorescence visualization of the activity of the xylanase cocktail on xylan in the yellow corn of the feed showed a substantial collapse in the morphology of cell walls. Secondly, the reduction in the viscosity of the digesta of the feed by the cocktail showed an effective degradation of the soluble fraction of xylan. Analysis of the xylan degradation products from broiler feeds by the xylanase cocktail showed that xylotriose and xylopentaose were the major xylooligosaccharides (XOS) produced. In vitro evaluation of the prebiotic potential of these XOS showed that they improved the growth of the beneficial bacteria Streptococcus thermophilus and Lactobacillus bulgaricus. The antibacterial activity of broths from XOS-supplemented probiotic cultures showed a suppressive effect on the growth of the extraintestinal infectious bacterium Klebsiella pneumoniae. Supplementing the xylanase cocktail in cereal animal feeds attenuated xylan's antinutritional effects by reducing digesta viscosity and releasing entrapped nutrients. Furthermore, the production of prebiotic XOS promoted the growth of beneficial bacteria while inhibiting the growth of pathogens. Based on these effects of the xylanase cocktail on the feed, improved growth performance and better feed conversion can potentially be achieved during poultry rearing.

In vitro digestibility and solubility of phosphorus of three plant-based meat analogues

Interest in plant-based meat analogues has increased and can be expected to be applied to pet foods, which necessitates the understanding of the nutrient supply in those foods. Our primary aim was to advance our understanding of the digestive properties of sterilized plant-based meat analogues. The impact of the preparatory processing steps on the solubility of meat analogues was studied. Meat analogues were made by mixing water, salt, and wheat gluten with soy protein isolate, pea protein isolate, or faba bean concentrate. Mixed materials were processed into model meat analogues using shear cell technology. Products were canned in water or gravy and sterilized. An animal-based canned pet food was made as a reference. Products sampled at the processing steps (mixing, shearing, sterilization) were digested in vitro. Samples of digestate were taken at the gastric phase (0 and 120 min) and small intestinal phase (120, 200, 280, and 360 min) for analysis of protein hydrolysis. The extent digestion of nitrogen and dry matter was determined at the end of incubation. Total phosphorus, soluble phosphorus after acid treatment, and after acid and enzymatic treatment were determined. The degree of hydrolysis after gastric digestion was low but increased immediately in the small intestinal phase; products based on pea had the highest values (56%). Nitrogen digestibility was above 90% for all materials at each processing step, indicating that bioactive compounds were absent or inactivated in the protein isolates and concentrate. Phytate seemed to play a minor role in meat analogues, but phosphorus solubility was influenced by processing. Shearing decreased soluble phosphorus, but this effect was partly reversed by sterilization. Nutrient digestibility as well as phosphorus solubility in plant-based products was higher than or comparable with the reference pet food. These findings show that the digestive properties of the tested plant-based meat analogues do not limit the supply of amino acids and phosphorus.

Two-stage fermentation of corn and soybean meal mixture by Bacillus subtilis and Lactobacillus acidophilus to improve feeding value: optimization, physicochemical property, and microbial community

Microbial treatment can reduce the antinutritional factors and allergenic proteins in corn-soybean meal mixture (CSMM), but the role of the microbial community in hypoallergenicity and digestibility during the fermentation process remains unclear. Therefore, the fermentation strains of Bacillus and LAB were determined, and the compatibility and fermentation process of two-stage solid fermentation composite bacteria were optimized, and the dynamic changes in physicochemical property and microbial community during two-stage fermentation were investigated. Results showed that Bacillus subtilis NCUBSL003 and Lactobacillus acidophilus NCUA065016 were the best fermentation combinations. The optimal fermentation conditions were inoculum 7.14%, solid-liquid ratio of 1:0.88 and fermentation time of 74.30 h. The contents of TI, β-conglycinin and glycinin decreased significantly after fermentation. Besides, TCA-SP, small peptides and FAA increased. Bacillus and Lactobacillus were the main genera. Pathogenic bacteria genera were inhibited effectively. This study suggests the feasibility of two-stage fermentation in improving the nutrient values and safety of the CSMM.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-023-01426-7.

Effects of phytase enzyme supplementation on growth performance, intestinal morphology and metabolism in Nile tilapia (Oreochromis niloticus)

Phytase is crucial in enhancing the bioavailability and release of phosphorus and other nutrients bound to phytic acid, making them more bioavailable for animal absorption. This study was carried out to inspect the effect of supplementing low phosphorus (P) diet with di-calcium phosphate (DCP) and liquid phytase enzyme (LP), which contains 1500 FTU/kg, on growth performance, intestinal morphometry, proximate body chemical composition, blood profile, immunity status, liver mitochondrial enzyme activities, the expression response and economic returns of Nile tilapia (Oreochromis niloticus). Three triplicate groups of fish (initial weight 5.405 ± 0.045 g, N = 90) were fed on three different diets for 90 days. The first was a control diet with zero DCP; the second was a control diet supplemented with 0.71% DCP; the third was a control diet supplemented with 0.03% LP. The groups were designated as CG, DCP and LP, respectively. Results showed that LP induced considerable improvements (p < 0.05) in FBW, body weight gain, weight gain rate, specific growth rate, HIS, viscero-somatic index, spleen-somatic index, feed conversion ratio, blood parameters and the histomorphometry assessment of intestinal villi absorptive capacity, compared with the other groups. Also, whole-body protein and lipid contents pointedly (p < 0.05) increased by LP, compared with the DCP group. A positive response (p < 0.05) to the phytase enzyme was noted in complexes I, III and IV of the mitochondrial liver complex enzyme activity. Likewise, the relative gene expression levels of (GHr-1, IGF-1, FAS and LPL) were notably (p < 0.05) upregulated by phytase enzyme, associated with DCP and control groups. Further, phytase recorded the highest total return and profit percentage. It can be concluded that Nile tilapia benefits from using phytase enzyme 1500 FTU/kg at 0.03% without adding DCP in terms of good performance and profits.

Inclusion of a Bacillus-based probiotic in non-starch polysaccharides-rich broiler diets

This study examined the effects of a 3-strain Bacillus-based probiotic (BP; Bacillus amyloliquefaciens and two Bacillus subtilis) in broiler diets with different rye levels on performance, mucus, viscosity, and nutrient digestibility. We distributed 720 one-d-old female broilers into 72 pens and designed nine diets using a 3 × 3 factorial approach, varying BP levels (0, 1.2 × 106, and 1.2 × 107 CFU/g) and rye concentrations (0, 200, 400 g/kg). On d 35, diets with 200 or 400 g/kg rye reduced broiler weight gain (BWG). Diets with 400 g/kg rye had the highest FCR, while rye-free diets had the lowest (p ≤0.05). Adding BP increased feed intake and BWG in weeks two and three (p ≤0.05). It should be noted that the overall performance fell below the goals of the breed. Including rye in diets reduced the coefficient of apparent ileal digestibility (CAID) for protein, ether extract (EE), calcium, phosphorus, and all amino acids (p ≤0.05). Rye-free diets exhibited the highest CAID for all nutrients, except for methionine, EE, and calcium, while diets with 400 g/kg of rye demonstrated the lowest CAID (p ≤0.05). BP in diets decreased phosphorus CAID (p ≤0.05). Diets containing 1.2 × 107 CFU/g (10X) of BP exhibited higher CAID of methionine than the other two diets (p ≤0.05). Diets containing 10X of BP showed higher CAID of cysteine than diets with no BP (p ≤0.05). Ileal viscosity increased as the inclusion level of rye in the diets increased (p ≤0.05). The ileal concentration of glucosamine in chickens fed diets with 400 g/kg of rye was higher than in those fed diets with no rye (p ≤0.05). Furthermore, ileal galactosamine concentrations were elevated in diets with 200 and 400 g/kg of rye when compared to rye-free diets (p ≤0.05). However, BP in diets had no impact on ileal viscosity, galactosamine, or glucosamine (p > 0.05). In conclusion, the applied Bacillus strains appeared to have a limited capacity to produce arabinoxylan-degrading enzymes and were only partially effective in mitigating the negative impacts of rye arabinoxylans on broilers.

Sweet potato flour (Ipomoea batatas) as natural antioxidant on carcass yield and meat physicochemical characteristics of Creole chickens of Mexico and Cobb 500

Antioxidants are considered functional additives against oxidative stress since they avoid nutritional decline in the meat. The main objective of the present study is to evaluate the effect of sweet potato flour (SPF) as a natural antioxidant on carcass yield and physicochemical characteristics of Creole chickens of Mexico (CChM) and Cobb 500 broilers. In total, 210 chickens (105 CChM and 105 Cobb 500 chickens) were randomly assigned to three treatments: 0, 500, and 1000 mg of SPF kg-1 of feed. The Cobb 500 chickens showed higher carcass yield (hot and cold), breast, and breast fillet, whereas the CChM had higher thigh yield (P ≤ 0.05). The yield on the previously mentioned variables was not affected by the inclusion levels of SPF. The initial pH differed because of the effect of the chicken's genotype and the addition of SPF, which was higher on Cobb 500 chicken and on those that were not supplemented with SPF. The birds' skin that consumed SPF presented higher yellowness after 24 h (P ≤ 0.05). CChM manifested a higher dry matter and protein content and a lower content of ash and fat (P ≤ 0.05). In conclusion, Cobb 500 chickens present a higher carcass yield and its components, in addition to a less acid pH; however, CChM offer a higher nutritional contribution, whereas the 500 and 1000 mg addition of SPF increases the skin yellowness, which makes it an alterorganic as a pigment on broiler chicken production.

Impact of feed additives and host-related factors on bacterial metabolites, mucosal integrity and immune response in the ileum of broilers

The present study aimed to investigate the effect of age, breed, and sex of broilers, as well as a probiotic or phytobiotic product on mucosal morphology, bacterial metabolites, and immune traits in the ileum of broilers. A total of 2,880 one-day-old male and female broiler chicks from two breeds (Ross308® and Cobb500®) were randomly assigned to 72 pens. Broilers were offered a wheat-soybean diet without (CO), or with either a probiotic (PO; 2.4 × 109 CFU/kg of Bacillus subtilis DSM32324 and DSM32325 and B. amyloliquefaciens DSM25840) or a phytobiotic (PY; grape extract, 165 ppm procyanidin and 585 ppm polyphenols of the diet) product. The trial was conducted with a 3 × 2 × 2 factorial arrangement of diet, breed, and sex in a completely randomized design (6 replicate-pens per treatment). At day 7, 21, and 35, one chicken per pen was slaughtered for collecting ileal tissue to evaluate of histomorphology and mRNA expression, as well as ileal digesta to measure bacterial metabolites. Data were subjected to ANOVA (the main factors; age, diet, breed, and sex) and Four-Way ANOVA (interactions) using GLM procedure. Overall, the concentration of acetate and total short chain fatty acids reached the peak and lactate decreased to its lowest on day 21, but their concentrations at day 7 and 35 were similar (p > 0.05). Spermine, spermidine, and ammonia decreased after day 7, while putrescine and cadaverine increased after day 21 (p < 0.05). mRNA expression of cytokines, mucin 2 (MUC2) and claudin 5 (CLDN5) was similar; increased from day 7 to 21 and decreased afterward (p < 0.05). Villus height, crypt depth and villus surface area increased with age (p < 0.05). Acidic goblet cells (GC) number and density increased after day 21 (p < 0.05). Ross broilers showed higher D-lactate concentration and IFN-γ expression, while Cobb broilers had greater IL-4, IL-6 and TNF-α expression and higher total GC number (p < 0.05). Female displayed higher villus height and GC number and density (mixed and total GC) than male (p < 0.05). The effect of dietary treatment was not found on any investigated variables (p > 0.05). In conclusion, aging of broilers affected ileal histomorphology, cytokine expression, and barrier integrity, as well as bacterial activity. These observed impacts could be attributed to host-microbiota interaction and the direct effects of bacterial metabolites on intestinal cells and immune system.

Standardized ileal digestibility of amino acids in cottonseed meal fed to pregnant and non-pregnant sows

This study determined the apparent ileal digestibility (AID) and standard ileal digestibility (SID) of crude protein (CP) and amino acids (AA) of six cottonseed meal (CSM) samples in pregnant and non-pregnant sows. Two CSM samples were processed by expelling with a CP level of 40.67% (ECSM41) and 44.64% (ECSM45), and four samples were processed by solvent-extracted which contained graded CP levels of 45% (SECSM45), 51.16% (SECSM51), 56.44% (SECSM56), and 59.63% (SECSM60). Landrace ×Yorkshire third parity sows, 7 at gestation and 14 non-pregnant, were fitted with T-cannula in the distal ileum. Pregnant sows were allotted to a 7 × 6 Latin square design with a cornstarch-based nitrogen-free (NF) diet and the six CSM diets, and non-pregnant sows were allotted to a replicated 7 × 3 Latin square design with seven diets and three periods, respectively, resulting in a total of six replicates per treatment. All experimental sows were fed 3.0 kg/d of the experimental diets. The AID of CP in ECSM41 (75.58%) was lower than in SECSM51 (80.42%), SECSM56 (80.50%), and SECSM60 (82.44%) diets for pregnant sows (P < 0.05). The AID of CP in ECSM41 (77.88%) was significantly lower than in SECSM60 (81.87%) diets for non-pregnant sows (P < 0.05). The physiological phase did not affect the AID of CP (P > 0.05). The SID of CP was affected by diets for both pregnant (P < 0.01) and non-pregnant sows (P = 0.06). The physiological phase also affected the SID of CP (P < 0.01). The AID of histidine, leucine, methionine, threonine, and tryptophan significantly differed between different CSM samples in both pregnant (P < 0.05) and non-pregnant sows (P < 0.05). The AID of dispensable AA aspartic acid, cysteine, glutamic acid, serine, and tyrosine differed between different CSM samples of both pregnant (P < 0.05) and non-pregnant sows (P < 0.05). For pregnant sows, the indispensable AA cysteine, glycine, proline, and tyrosine had significantly different SID between different groups (P < 0.05). For non-pregnant sows, the SID of arginine, lysine, methionine, threonine, aspartic acid, cysteine, and serine had different values among different diets (P < 0.05). In conclusion, the current study presented that the ileal AA digestibility of CSM fed to pregnant and non-pregnant sows increased with the decreased of fiber content, and the current findings can contribute to a precise formulation of diets for sows using CSM.

Oil Extracted Moringa peregrina Seed Cake as a Feed Ingredient in Poultry: A Chemical Composition and Nutritional Value Study

The chemical composition, antioxidant activity, tannic acid content, mineral, fatty acid, and amino acid profiles of oil-extracted Moringa peregrina seed meal (OEMPSM) were determined. Apparent (AME) and true (AMEn) metabolizable energy and apparent (AAAU) and true (TAAU) amino acid utilization were evaluated using a precision feeding trial. The protein (CP) quality was evaluated by a total efficiency analysis method. The antioxidant activity, gauged by 2,2-diphenyl-1-picrylhydrazyl (DPPH), was 237, 353, and 15.2 mg/mL for the water and ethanol extracts, and ascorbic acid, respectively. Tannic acids were 131.4 mg/100 g dry weight. The OEMPSM had 27.2% CP and 22.4, 15.1, and 15.8 MJ/kg of gross energy, AME and AMEn, respectively. The neutral detergent fiber, acid detergent fiber, and hemicellulose were 40.2, 29.7, and 10.5% DM, respectively. The 15.41% of total fatty acids were saturated and 84.57% unsaturated. The AAAU and TAAU of OEMPSM were 30.92% and 61.06%, respectively. From findings, OEMPSM comprises a valuable level of bioactive substances, amino acids, fatty acids, minerals, and energy; it can provide up to 1.12% of the requirements of total amino acids of chickens (1-21 days); however, the quality of its protein was found to be 44.6% less than that of protein of soybean meal.

Nutrient Composition and In Vitro Fermentation Characteristics of Sorghum Depending on Variety and Year of Cultivation in Northern Italy

Sorghum is the fifth most produced cereal in the world and is a source of nutrients and bioactive compounds for the human diet. This study examined the nutrient composition and in vitro fermentation characteristics of sorghum varieties grown in 2020 and 2021 (n = 15 × 3 × 2) across three locations in the north of Italy (Bologna, Padova, and Rovigo). In 2020, the crude protein content of sorghum was significantly higher in the region of Padova than in the region of Bologna (124 vs. 95.5 g/kg dry matter). However, crude fat, sugar, and gross energy levels showed no significant differences among the different regions in 2020. In 2021, the levels of crude protein, crude fat, sugar, and gross energy had no significant differences among different sorghum varieties harvested from the three regions. Significant differences in some mineral contents were found among the samples particularly in manganese and zinc in both years. After 24 h of fermentation of two different sorghum hybrids (hybrids 1 and 2 of both years harvested in Bologna, n = 4 × 2 × 2), the pH value was significantly higher in hybrid 1 of year 2021 (3.98) than in the other fermented samples (range: 3.71–3.88). The sorghum harvested from the region of Bologna had a significantly higher viscosity value (1.22 mPa·s) compared to other regions (1.8–1.10 mPa·s) in 2021 only. The results show that the nutritional value and viscosity of different sorghum varieties could differ depending on the location and year of cultivation.

Alterations in bacterial metabolites, cytokines, and mucosal integrity in the caecum of broilers caused by feed additives and host-related factors

A total of 2,880 one-day-old male and female broiler chicks from two breeds, Ross308 and Cobb500 were randomly assigned to 72 pens. Broilers were offered three diets: a wheat-soybean diet without (CO), or with either a probiotic (probiotic; 2.4 x 10⁹ CFU/kg diet of Bacillus subtilis DSM32324 and DSM32325 and B. amyloliquefaciens DSM25840) or a phytobiotic (phytobiotic; grape extract with 165 ppm procyanidin and 585 ppm polyphenol) product. The trial was conducted with a 3 × 2 × 2 factorial arrangement of diet, breed and sex in a completely randomized design and consisted of 6 replicate-pens per treatment (40 birds per pen). At day 7, 21, and 35, one chicken per pen was slaughtered for caecal sampling to quantify bacterial metabolites (digesta) as well as evaluate mRNA abundance and histomorphology (tissue). Data were subjected to ANOVA using GLM procedure to evaluate age, diet, breed and sex and their interactions. Spearman’s correlation (r) was analyzed between metabolite concentration and mRNA abundance. Overall, the concentration of short chain fatty acids increased with age, while lactate decreased from day 7 to 21 (p < 0.05). The mRNA abundance of IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-17α, IL-18, IFN-γ and TGF-β2 increased with age but IL-1β and TNF-α increased in abundance from day 7 to 21 and then decreased (p < 0.05). Abundance of MUC2 and CLDN5 increased after day 21 (p < 0.05). Caecal crypt depth increased with age (p < 0.05). Acidic goblet cell (GC) number peaked at day 21 (p < 0.05), while mixed GC number was not affected by age. A few impacts of breed, diet and interactions on the investigated variables showed no meaningful biological pattern. Propionate positively correlated with all cytokines investigated (r = 0.150–0.548), except TNF-α. Lactate negatively correlated with pro-inflammatory cytokines like IL-1β (r = −0.324). Aging affected caecal histomorphology, bacterial activity and genes responsible for barrier integrity and inflammatory response. This effect could be attributed to the interaction between gut microbiota and immune system as well as the direct effect of metabolites on gut histomorphology and cytokine mRNA abundance.

Fermentation Characteristics of Rye and Sorghum Depending on Water:Feed Ratio

This study was conducted to determine the fermentation characteristics of rye or sorghum mixed with different ratios of water (25%, 37.5%, 50%, 62.5%, and 75% in dry matter (DM)), incubated up to 48 h. The pH of the fermented rye at a DM content of 25% after 24 h had the lowest values (3.57) compared to that at a DM content of 75% (6.42). In fermented sorghum, pH values were lower than 4 already after incubation at 25% DM for 12 h (3.93) in comparison to that at DM content 75% (6.51). The L-lactic acid concentration in the fermented rye with 25% DM content after 24 h was significantly the highest (18.7 g/kg DM), as was that of sorghum with 25% DM content after 24 h (22.2 g/kg DM). Moreover, the acetic acid level in the fermented rye with 25% DM content after 24 h was significantly the highest (3.02 g/kg DM) compared to the other DM contents of fermented rye. Also, in fermented sorghum (25% DM), the acetic acid content was significantly the greatest (1.49 g/kg DM) in comparison to the other DM contents of fermented sorghum. Overall, fermented rye and sorghum containing 25 or 37.5% DM for 24 h and 12 h for rye and sorghum, respectively are sufficient for fermentation to be optimized based on the values of pH and lactic acid content, except for acetic acid content, which may negatively affect the palatability in animals.

Effects of treating Prosopis juliflora pods with multienzyme, with and without bacterial cultures on in vitro dry matter digestibility (IVDMD), fermentation kinetics, and performance of growing pigs

This study was conducted to determine the effects of treating Prosopis juliflora pods with multienzyme and bacterial cultures on in vitro dry matter digestibility (IVDMD), fermentation kinetics, and performance of growing pigs. Experiment one consisted of a pepsin-pancreatine hydrolysis method to simulate, in vitro, the pig digestive system and was followed by in vitro gas production to assess fermentation kinetics. Samples of ground Prosopis pod meal (GPPM) were allocated to four treatments with three replicates each. Treatments included GPPM treated with multienzyme (Natuzyme®) (T1); untreated (GPPM) (T2); GPPM fermented with (Lactobacillus plantarum MTD1 Ecosyl ®) (T3), and GPPM treated using natural fermentation (T4). The second experiment assessed the performance of pigs fed the best treatment from experiment 1. Thirty Landrace × large white crosses of 20 ± 2 kg were allotted to five treatments with six pigs each (replicates). The dietary treatments were PC, 0% GPPM + enzyme; NC, 0% GPPM and 0% enzyme; D1, 10% GPPM + enzyme; D2, 20% GPPM + enzyme; and D3, 30% GPPM + enzyme. A randomized complete block design was used for both experiments. Enzyme treatment (T1) and T3 improved the IVDMD of the GPPM compared to T2 by 3.68% and 1.2%, respectively (p < 0.05). Cumulative gas was highest and Tmax lowest for T1 but significantly different only to T4 (p < 0.05). Average daily gain and intake were highest for pigs fed GPPM up to 10% (PC, D1). Feed conversion ratio increased with the level of GPPM in the diet. The results suggest Prosopis juliflora pods treated with enzymes can be added in pig diets up to 30%.

Performance and Egg Quality of Laying Hens Fed Diets Containing Raw, Hydrobarothermally-Treated and Fermented Rapeseed Cake

The present study was conducted to investigate how raw rapeseed cake (RRC), hydrobarothermally-treated rapeseed cake (HRC) and fermented rapeseed cake (FRC) fed to laying hens over a period of 12 weeks affected their performance, and the quality, fatty acid (FA) profile and oxidative stability of eggs. A total of 304 Hy-Line Brown laying hens at 36 weeks of age were distributed in a completely randomized design to four treatment groups with 38 replicates per treatment and two hens per replicate. The birds had ad libitum access to feed and water throughout the study. During the experiment, the birds were fed isonitrogenous and isocaloric diets in mash form, with various protein sources. In the control group (C), soybean meal (SBM) was the main source of dietary protein, whereas the experimental groups were fed diets containing 20% of RRC, HRC or FRC. Hydrobarothermal treatment and fermentation decreased the glucosinolate (GLS) content of RC, and fermentation reduced the concentration of phytate phosphorus (PP). In comparison with the RRC group, layers from the HRC and FRC groups were characterized by higher laying performance, comparable with that in group C. Irrespective of its physical form, RC added to layer diets adversely affected eggshell quality in all experimental groups, whereas albumen quality was highest in the FRC group. In comparison with group C, diets containing RRC, HRC and HRC led to a significant decrease in the content of saturated fatty acids (SFAs), an increase in the proportion of n-3 and n-6 polyunsaturated fatty acids (PUFAs) in the total FA pool in egg yolks, and a decrease in the n-6/n-3 PUFA ratio. The inclusion of RRC, HRC and FRC in layer diets decreased the activity of superoxide dismutase (SOD) in egg yolks, relative to group C. Group FCR eggs were characterized by the highest activity of catalase (CAT) and the lowest lipid peroxides LOOH concentration, compared with the remaining groups. The addition of RC to layer diets did not compromise the sensory quality of eggs, and eggs produced in group FRC received the highest overall score. It can be concluded that the inclusion of 20% RRC, HRC and FRC in layer diets does not compromise the sensory quality of eggs and has a beneficial influence on the FA profile and antioxidant potential of egg yolks. The use of FRC is recommended because it contributes to the highest laying performance, superior albumen quality and the highest sensory quality of eggs, relative to RRC and HRC.

Development and Functional Properties of Intestinal Mucus Layer in Poultry

Intestinal mucus plays important roles in protecting the epithelial surfaces against pathogens, supporting the colonization with commensal bacteria, maintaining an appropriate environment for digestion, as well as facilitating nutrient transport from the lumen to the underlying epithelium. The mucus layer in the poultry gut is produced and preserved by mucin-secreting goblet cells that rapidly develop and mature after hatch as a response to external stimuli including environmental factors, intestinal microbiota as well as dietary factors. The ontogenetic development of goblet cells affects the mucin composition and secretion, causing an alteration in the physicochemical properties of the mucus layer. The intestinal mucus prevents the invasion of pathogens to the epithelium by its antibacterial properties (e.g. β-defensin, lysozyme, avidin and IgA) and creates a physical barrier with the ability to protect the epithelium from pathogens. Mucosal barrier is the first line of innate defense in the gastrointestinal tract. This barrier has a selective permeability that allows small particles and nutrients passing through. The structural components and functional properties of mucins have been reviewed extensively in humans and rodents, but it seems to be neglected in poultry. This review discusses the impact of age on development of goblet cells and their mucus production with relevance for the functional characteristics of mucus layer and its protective mechanism in the chicken’s intestine. Dietary factors directly and indirectly (through modification of the gut bacteria and their metabolic activities) affect goblet cell proliferation and differentiation and can be used to manipulate mucosal integrity and dynamic. However, the mode of action and mechanisms behind these effects need to be studied further. As mucins resist to digestion processes, the sloughed mucins can be utilized by bacteria in the lower part of the gut and are considered as endogenous loss of protein and energy to animal. Hydrothermal processing of poultry feed may reduce this loss by reduction in mucus shedding into the lumen. Given the significance of this loss and the lack of precise data, this matter needs to be carefully investigated in the future and the nutritional strategies reducing this loss have to be defined better.

The Effect of Yeast Fermentation of Two Lupine Species on the Digestibility of Protein and Amino Acids, Microflora Composition and Metabolites Production in the Ileum of Growing Pigs

Simple Summary

The fermented feed component in pigs‘ diet may influence the microbiota of the gastrointestinal tract, improve the use of nutrients from the diet, and reduce the level of excreted N and P. The aim of this study was to investigate the effects of raw and Candida utilis-fermented yellow and narrow-leaved lupine seeds on the apparent ileal digestibility coefficients of protein and amino acids and the metabolic activity of the intestinal microflora in five cannulated male pigs. Fermentation significantly improved the ileal digestibility of protein, asparagine, threonine, tyrosine, histidine, and arginine in the lupine seeds and increased the counts of total bacteria and yeast, the pH value, isobutyrate and isovalerate concentrations in the ileal digesta, but decreased the dry matter and ammonia content. The narrow-leaved lupine seeds were characterized by higher digestibility of asparagine, threonine, serine, alanine, valine, isoleucine, and arginine. The digesta of the pigs fed with these seeds had higher counts of lactic acid bacteria and moulds but lower total bacteria count than the digesta of the pigs fed with yellow lupine seeds.

Abstract

The aim of this study was to investigate the effects of raw and Candida utilis-fermented yellow (YL) and narrow-leaved lupine (NL) seeds on the apparent ileal digestibility coefficients (AID) of protein and amino acids in pigs and the metabolic activity of their intestinal microflora. Five cross-bred castrated 25-kg barrows were surgically fitted with a T-cannula in the distal ileum and housed individually in metabolic cages. They were fed five semi-synthetic diets containing only one source of protein: soybean meal (SBM), raw or fermented yellow lupine seeds (RYL or FYL), raw or fermented narrow-leaved lupine seeds (RNL or FNL). The study period consisted of six-day adaptation to the diet and one-day collection of digesta, which was sampled for microbial and chemical analyses. The AID coefficients of protein and amino acids were calculated with the marker method with TiO₂. One-way (feed effect) and two-way (variety effect, fermentation effect) analysis of variance (ANOVA) with Duncan’s test at p < 0.05 were applied. The digesta from the SBM and FNL variants had significantly higher (p < 0.05) AID coefficients of protein, asparagine, threonine, serine, isoleucine, leucine, histidine, and tyrosine, whereas the SBM variant was characterized by the lowest AID of cystine and the highest AID of alanine and methionine (p < 0.05). The ileal digesta of the pigs fed with FYL contained more bacteria, whereas the count of yeast was higher in the FNL variant. The digesta of the pigs from the FNL and RYL variants had the highest count of moulds (p < 0.05), whereas the digesta in the FYL, SBM, and RNL variants had almost no moulds at all. The ileal dry matter content was significantly lower in SBM group. The lowest pH was noted in the RYL variant (p < 0.05). The content of ammonia and total volatile fatty acids in the ileal digesta of the SBM variant was the lowest (p < 0.05). Fermentation significantly improved the AID of protein, asparagine, threonine, tyrosine, histidine, and arginine, increased the counts of total bacteria and yeast, the pH value, and isobutyrate and isovalerate concentrations, but decreased the dry matter and ammonia content (p < 0.05). The digesta of the NL variants was characterized by higher AID of asparagine, threonine, serine, alanine, valine, isoleucine, and arginine, and higher counts of LAB and moulds but lower total bacteria count than in the YL variants. The ileal pH was lower in the YL variants, where higher isobutyrate and butyrate concentrations (p < 0.05) were observed. To sum up, fermentation increased the counts of the ileal microbiota and improved the digestibility coefficients of protein and some amino acids. The narrow-leaved lupine seeds resulted in more positive changes in the digesta of growing pigs than yellow lupine.

Nutrition and Digestive Physiology of the Broiler Chick: State of the Art and Outlook

Simple Summary

The first week after hatch is the most challenging period in the life of broilers. The digestive tract of the newly hatched chick is immature and must undergo dramatic changes before it can efficiently digest and absorb nutrients. The gut is the vital organ where nutrient digestion and absorption take place. Ontogenic changes that accompany improved digestion and absorption include increased secretion of digestive enzymes, increase in the gut absorptive surface area, and enhanced nutrient transporters. The obvious limiting factors are the secretion and activities of digestive enzymes, and the surface area for absorption. These limitations are overcome as the birds grow older, with concurrent improvements in nutrient utilization. In addition, substantial changes also take place in the physical and functional development of the immune system and intestinal microbial ecology. However, the focus of the current review was on nutrition-related challenges and nutritional approaches to assist the chick during this highly demanding period.

Abstract

Because the intestine is the primary nutrient supply organ, early development of digestive function in newly hatched chick will enable it to better utilize nutrients, grow efficiently, and achieve the genetic potential of contemporary broilers. Published data on the growth and digestive function of the gastrointestinal tract in neonatal poultry were reviewed. Several potential strategies to improve digestive tract growth and function in newly hatched chick are available and the options include breeder nutrition, in ovo feeding, early access to feed and water, special pre-starter diets, judicious use of feed additives, and early programming.

Influence of Fermented Diets on In Vitro Survival Rate of Some Artificially Inoculated Pathogens—A Preliminary Study

Improving the hygienic status of feed ingredients by biotechnological processes as fermentation is of the greatest concern. This preliminary study aimed to investigate whether there are relevant effects of fermented liquid feed (FLF) on the survival of potential pathogens in vitro. The feed (fresh basis) consisted of 50% rye, 30% rapeseed extracted meal, 10% barley and 10% wheat. Glass bottles were filled about 14.1 g water (38 °C) containing the diluted starter culture and feed (8.81 g). Fermentation led to high levels of lactate (5–7% of dry matter), low pH values (<4.0) and low levels of acetic acid (<1% of dry matter) in the FLF. The survival rate of pathogens added, such as Salmonella enterica serovar Typhimurium, Escherichia coli and Clostridium perfringens after 6 h of controlled fermentation, was significantly reduced (<2 log10 CFU/g). The counts of Candida krusei in FLF at 3 h and 6 h post inoculation remained almost unchanged regardless of the incubation time. Even adding sodium-benzoate at a concentration of up to 0.25% in the liquid feed did not reduce the survival of C.krusei during fermentation. Based on this in vitro study, feeding of FLF seems a promising strategy to reduce pathogen transmission but has to be confirmed on natural feeds by pathogens for increasing the hygienic properties.