The food for feed concept. Performance of broilers fed hotel food residues.

1. In recent times the use of food waste in animal diets has gained considerable attention because of the increasing demand to cover the needs of human population and the high prices of conventional, arable based, animal feeds.2. The aim of the present study was to investigate the effect of adding dried human food waste to the diet of meat-type chickens (broilers). Two hundred, one-day-old broilers were divided into two treatment groups, with 10 replicate pens containing 10 birds per pen. The duration of the study was 42 days. In the control (C), the diet did not contain any food waste, whereas in the second treatment (T) food waste residues from hotels made up 15% of the diet. Diets had similar crude protein and metabolisable energy content.3. Feed intake and body weight were recorded in order to calculate weight gain and feed conversion ratio (FCR). Carcase and breast muscle yield, the weight of selected internal organs and the level of selected biochemical and haematological parameters were determined. Quality of breast muscle meat was assessed.4. Broilers fed the control treatment consumed more feed and gained more weight compared to broilers fed waste; however, the FCR was similar. No major differences were seen for internal organ weights and haematological parameters, although some differences were observed in colour traits and shear force of meat. It was concluded that there is a potential for use of food waste in broiler diets.

Inclusion of IgY in a dog's diet has moderate impact on the intestinal microbial fermentation.

AIMS: This study aimed to evaluate the impact of immunoglobulin Y (IgY) in a diet on the systemic health and the gastrointestinal tract (GIT) of dogs. METHODS AND RESULTS: Sixteen healthy 11-month-old Beagle dogs were distributed at random (eight animals per treatment) in two treatments groups: control (0 g kg-1 IgY) and test (2 g IgY per day). The animals were evaluated on days 0 and 40 for a complete blood count (CBC) and biochemical profiles (ALT, ALP, creatinine and urea). Faecal samples were collected from days 35 to 40 to measure nutrient digestibility, faecal characteristics, sialic acid, intestinal microbiota composition and microbial metabolites. The CBC, biochemical profiles, apparent nutrient digestibility and faecal characteristics did not differ between the two treatment groups (P > 0·05). Dog faeces that received IgY were characterized by lower sialic acid and n-valeric concentration, as well as an increase in n-butyric concentration, in contrast to dogs fed a diet without IgY (P < 0·05). The other microbial faecal metabolites did not differ between the two treatment groups (P > 0·05). There tended to be an increase in the copy number of Clostridium cluster XIVa (Clostridium coccoides group) in the IgY group in contrast to the control group (P = 0·07). The other bacteria analysed did not differ between the treatment groups (P > 0·05). The colonic pH in the IgY group was lower than in control group (P < 0·05). CONCLUSIONS: The addition of IgY in the diet of healthy dogs maintains the microbial balance and has an interesting effect on microbial metabolites. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of IgY, antibodies produced by laying hens, in animal feed is an alternative for the prevention and treatment of intestinal diseases in companion animals.

Effects of isoquinoline alkaloids from Macleaya cordata on physiological, immunological and inflammatory parameters in healthy beagles: Alkaloids in dog nutrition.

The aim of the study was to investigate nutritional, physiological and immunological effects of a plant-derived blend of isoquinoline alkaloids (Sangrovit® Extra) in healthy dogs. Two groups of healthy, adult beagles (N = 10) were tested in a cross-over experiment, lasting two consecutive three-week periods. The experimental group received 1.2 g additive/kg feed, according to the recommendation of 10-20 mg/kg live weight per day. The control group received the same feed without additive. Complete blood count, immunological parameters and amino acid concentrations in serum were assessed. Faeces were analysed for short-chain fatty acids, lactate and ammonium; moreover, their quantity and consistency were determined. Neither feed intake, total apparent nutrient digestibility (crude protein and fat, organic matter, sodium, potassium) were affected by intake of the product. Lymphocyte and monocyte counts were slightly increased in both groups. Elevation was not treatment dependant. IgA, IgG, haptoglobin in serum and flow cytometric phenotyping of peripheral lymphocytes were not affected by alkaloids supplementation. Numerically greater methionine concentrations in blood serum occurred in the experimental group (p = 0.182). Quantity and consistency of faeces and ammonium concentration in faeces were not affected by the additive. Faecal concentrations of short-chain organic acids differed between groups (acetic acid, % of total SCFA: control group 52.3 ± 5.2 vs. experimental group 57.1 ± 4.5, p = 0.042), lactate concentrations (d-, l- and total) did not. Due to the shift of SCFA proportions in faeces, an effect of isoquinoline alkaloids (IQs) on the metabolic activity of intestinal microbiota is probable. In conclusion, the addition of IQs in the given dose was well tolerated and did not have adverse effects in healthy dogs.

Impact of hyperlipidaemia on intermediary metabolism, faecal microbial metabolites and urinary characteristics of lipoprotein lipase deficient vs. normal cats.

Findings in humans and rats indicate that hyperlipidaemia may be associated with enhanced endogenous oxalate (Ox) synthesis, which may be relevant for calcium oxalate (CaOx) urolith formation. Moreover, changes in lipid metabolism are proposed to negatively affect gut microbiota. This study aimed to investigate those potential interactions in hyperlipidaemic cats. Therefore, 10 normal control cats and seven lipoprotein lipase (LPL)-deficient cats were fed a low-fat diet for seven weeks. During the last week of the study, cats were housed in metabolic cages to collect urine and faeces. Blood was taken on the last day of the study. The LPL-deficient cats had significantly higher serum triglyceride concentrations than normal cats, while lactate dehydrogenase (LDH) activity was not different. Urinary relative supersaturation with CaOx, urinary Ox, calcium, and citrate excretions, and urine pH did not differ between groups. Lower faecal acetic, propionic and total short-chain fatty acid concentrations were observed in the LPL-deficient cats. In conclusion, hyperlipidaemia does not appear to be a specific risk factor for CaOx urolith formation in cats. In contrast to results in rats, hyperlipidaemia was not accompanied by elevated serum LDH activity. As LDH can synthesise Ox from glycolate or other precursors, this might be one possible explanation for the similar urinary parameters in the LPL-deficient and normal cats. Non-diet-induced hyperlipidaemia was not associated with marked changes in faecal microbial metabolites, suggesting no differences in the composition of the intestinal microbiota.

Encapsulated benzoic acid supplementation in broiler diets influences gut bacterial composition and activity.

1. The present study investigated the effects of encapsulated benzoic acid (BA) supplementation in broiler feed on performance and gastrointestinal microbiota. 2. Eighty broilers were randomly divided into two groups. Birds in the control group were fed on maize-soybean-based diets. Birds in the treatment group were provided the same diet supplemented with 2 g/kg BA encapsulated in a vegetable oil matrix. 3. At the end of the trial (d 35), pH, bacterial composition and metabolites were determined in the crop, jejunum, ileum and caecum. 4. Growth performance variables and pH were not significantly different. 5. BA concentration decreased rapidly in the proximal gut. However, the treatment diet showed higher BA in the crop, jejunum, ileum and caecum. 6. Total lactate in the crop and D-lactate in the jejunum was higher in the BA treated group. Caecal total and branched chain fatty acids were decreased due to the treatment. 7. Lactobacilli populations were significantly altered by BA supplementation. A trend for increased lactobacilli was observed in the crop, while it became significant in the jejunum and ileum. Lactobacillus species responded differently to the treatment. Four of 5 measured Lactobacillus species, particularly in the ileum, followed the course observed for total lactobacilli; only Lactobacillus salivarius was not modified. 8. Correlation analysis showed that BA modified the intestinal microbiota. Lactobacilli correlated negatively to all studied clostridial clusters and enterobacteria. Clostridial clusters IV and XIVa were significantly increased in the jejunum, whereas only clostridial cluster XIVa was increased in the caecum. 9. Encapsulated BA modified the intestinal microbiota which can lead to the conclusion, that the main beneficial mode of action of BA in the gut appears to be the enhancement of lactic acid bacteria, which in turn may act as a vanguard against pathogens.

Influence of medium-chain fatty acids and short-chain organic acids on jejunal morphology and intra-epithelial immune cells in weaned piglets.

Medium-chain fatty acids (MCFA) and short-chain organic acids (SOA) are often used as feed additives in piglet diets. There are limited studies in pigs describing the impact of MCFA or SOA on gut morphology and the local immune system. The aim of this study was to investigate whether the supplementation of SOA (0.41% fumaric acid and 0.32% lactic acid), or the combination of SOA with MCFA (0.15% caprylic and capric acid) would have effects on gut morphology and intestinal immune cells in weaned piglets. A total number of 72 weaned piglets were randomly allocated into three experimental groups. Tissue samples of six animals per group were used to investigate the potential impact of the feed additives on villus length and crypt depth of the jejunum and to quantify intra-epithelial lymphocytes (IEL). CD3-positive IEL were determined via immunohistochemistry (IHC) and flow cytometry (FC), whereas CD2-, CD5-, CD8ß-, CD16- and γδ TCR-positive IEL were only analysed by FC. The supplementation of MCFA and SOA did not significantly affect morphometric data. The FC data indicated that SOA significantly increased the quantity of CD2- CD8- γδ T cells in the jejunum epithelium. Both IHC and FC analyses of pig jejunum confirmed that the majority of IEL expressed the surface marker CD3 and could be classified as cytotoxic T lymphocytes. In conclusion, the data indicated that SOA increased the proportion of CD2- CD8- γδ T cells in the jejunal epithelium. Thus, SOA might enable a beneficial effect on the local immunity by increasing the constitutive number of potential effector cells to defeat infectious diseases.

Sodium in feline nutrition.

High sodium levels in cat food have been controversial for a long time. Nonetheless, high sodium levels are used to enhance water intake and urine volume, with the main objective of reducing the risk of urolithiasis. This article is a review of current evidence of the putative risks and benefits of high dietary sodium levels. Its secondary aim is to report a possible safe upper limit (SUL) for sodium intake. The first part of the manuscript is dedicated to sodium physiology, with a focus on the mechanisms of sodium homeostasis. In this respect, there is only few information regarding possible interactions with other minerals. Next, the authors address how sodium intake affects sodium balance; knowledge of these effects is critical to establish recommendations for sodium feed content. The authors then review the consequences of changes in sodium intake on feline health, including urolithiasis, blood pressure changes, cardiovascular alterations and kidney disease. According to recent, long-term studies, there is no evidence of any deleterious effect of dietary sodium levels as high as 740 mg/MJ metabolizable energy, which can therefore be considered the SUL based on current knowledge.

Effect of feed grinding methods with and without expansion on prececal and total tract mineral digestibility as well as on interior and exterior egg quality in laying hens.

The grinding of cereals by various milling methods as well as thermal treatment of feed may influence mineral digestibility and egg quality. The present study investigated the effect of feed produced by disc mill (D) and wedge-shaped disc mill (WSD), as mash (M) or expandate (E) on apparent ileal absorption (AIA) and apparent total digestibility (ATD) of calcium, phosphorus, magnesium, zinc, manganese, copper and iron, as well as on egg quality in laying hens. A total of 192 hens (Lohmann Brown) aged 19 wk, were assigned using a randomized design with a 2 × 2 factorial arrangement. Four experimental diets were offered ad libitum. Eggs were analyzed for weight, shape index, area, shell weight per unit surface area, yolk color, air cell, blood spot, Haugh unit, albumen and yolk measures (index, weight, height, width and length), shell measures (surface area, stability, density, thickness and membrane weight), as well as percent contents of albumen, yolk, shell, and shell membrane. The ATD for phosphorus, manganese, and copper was higher in WSD compared with D treatment (P = 0.028, P = 0.028 and P = 0.016, respectively). The interaction between milling methods and thermal treatment influenced ATD of copper (P = 0.033), which was higher in WSD+M group (41.0 ± 20.2) compared with D+E group (-3.21 ± 25.1), whereas no differences were observed for D+M (1.90 ± 37.8) and WSD+E (8.02 ± 36.2) groups. Egg stability tended to be higher in E compared with M treatment (P = 0.055). Albumen weight, percentage albumen weight, and albumen: yolk were higher and percentage yolk weight was lower in D compared with WSD treatment (P = 0.043, P = 0.027, P = 0.024, and P = 0.041, respectively). Number of blood spots was higher in E than M treatment (P = 0.053). In conclusion, use of a wedge-shaped disc mill resulted in higher ATD for phosphorus, manganese, and copper than use of a disc mill; however, digestibility for majority of minerals as well as egg quality parameters was comparable. Therefore, feed produced by either disc mill or wedge-shaped disc mill as mash or expandate may be used for laying hens without negative effects on egg quality.

Effect of supplementation of phytogenic feed additives (powdered vs. encapsulated) on performance and nutrient digestibility in broiler chickens.

Inclusion of phytogenic feed additives (PFA) in feed may enhance performance of broilers. Levels of essential oils in powdered form (characterized by menthol and anethole) at 150 mg/kg (P-150) and matrix-encapsulated form (characterized by carvacrol, thymol, and limonene) at 100 mg/kg (ME-100) were supplemented in diet to investigate their effect on performance (trial 1) and apparent ileal digestibility (AID) of nutrients (trial 2) in broilers. A total of 480 1-day-old broilers (Cobb 500) were used in trial 1 and 120 broilers in trial 2. Broilers were distributed in 24 pens with 8 pens per treatment (trial 1) and 6 pens with 2 pens per treatment (trial 2), with 20 birds per pen. Feed and water were offered ad libitum throughout the experimental periods in both trials. In trial 1, body weight of birds at d 42 and overall body weight gain from d 1 to d 42, was higher in treatment ME-100 than birds in control treatment (P = 0.023 and P = 0.024, respectively). Feed efficiency during finisher phase was improved in treatment ME-100 relatively to control and P-150 treatments (P = 0.035). At d 21 in trial 2, the apparent ileal digestibility of crude protein was higher in ME-100 treatment in comparison with control and P-150 treatments (P < 0.001). Apparent ileal absorption (AIA) of phosphorus was higher in ME-100 treatment than control treatment (P = 0.028). AID of cysteine was higher in both phytogenic additive supplemented treatments in comparison with control treatment (P = 0.001). In conclusion, inclusion of a powdered phytogenic additive characterized by menthol and anethole at 150 mg/kg had no effect but only a tendency towards improved performance and AIA of phosphorus, whereas essential oils addition in encapsulated form characterized by caravacol, thymol, and limonene at 100 mg/kg improved performance as well as apparent ileal digestibility of nutrients in broilers, possibly due to improved secretion of digestive enzymes.

Effect of dietary α-tocopherol on the bioavailability of lutein in laying hen.

Lutein and its isomer zeaxanthin have gained considerable interest as possible nutritional ingredient in the prevention of age-related macular degeneration (AMD) in humans. Egg yolk is a rich source of these carotenoids. As an oxidative sensitive component, antioxidants such as α-tocopherol (T) might contribute to an improved accumulation in egg yolk. To test this, chickens were fed lutein esters (LE) with and without α-tocopherol as an antioxidant. After depletion on a wheat-soya bean-based lutein-poor diet for 21 days, laying hens (n = 42) were equally divided into three groups and fed the following diets for 21 days: control (basal diet), a LE group (40 mg LE/kg feed) and LE + T group (40 mg LE plus 100 mg T/kg feed). Eggs and blood were collected periodically. Carotenoids and α-tocopherol in yolk and blood plasma were determined by HPLC. Egg yolk was also analysed for total carotenoids using a one-step spectrophotometric method (iCheck((™)) ). Lutein, zeaxanthin, α-tocopherol and total carotenoids in egg yolk were highest after 14 days of feeding and decreased slightly afterwards. At the end of the trial, eggs of LE + T group contained higher amount of lutein (13.72), zeaxanthin (0.65), α-tocopherol (297.40) and total carotenoids (21.6) compared to the LE group (10.96, 0.55, 205.20 and 18.0 mg/kg, respectively, p < 0.05). Blood plasma values of LE + T group contain higher lutein (1.3), zeaxanthin (0.06) and tocopherol (20.1) compared to LE group (1.02, 0.04 and 14.90 mg/l, respectively, p < 0.05). In conclusion, dietary α-tocopherol enhances bioavailability of lutein reflecting higher content in egg yolk and blood plasma. Improved bioavailability might be due to increased absorption of lutein in the presence of tocopherol and/or a greater stability of lutein/zeaxanthin due to the presence of α-tocopherol as an antioxidant.

Implication of milling methods, thermal treatment, and particle size of feed in layers on mineral digestibility and retention of minerals in egg contents.

Feed production with different milling methods, thermal treatment, and particle size may influence mineral digestibility and retention in eggs. The present study investigated the impact of roller (R) and hammer (H) mills, mash (M) and expandate (E) with fine (F) and coarse (C) particle sizes, on apparent ileal absorption (AIA) and apparent total digestibility (ATD) and retention of calcium, phosphorus, magnesium, zinc, manganese, copper and iron in yolk, albumen, and shell. A total of 384 hens (Lohmann Brown), 19 weeks old, were assigned using a randomized design with a 2×2×2 factorial arrangement. Eight experimental diets were offered ad libitum during the whole experimental period and one week before for diet adaption. The AIA of magnesium, zinc, copper, and iron was higher in treatment R in comparison with treatment H (P<0.01, P≤0.03, P<0.01 and P<0.01, respectively). The AIA of magnesium was higher in treatment M than treatment E (P<0.01). The AIA of magnesium was higher in treatment C in comparison with treatment F (P≤0.05) due to particle size. The ATD of copper and iron was higher in treatment R than treatment H (P<0.01 and P≤0.03, respectively). The ATD was higher for phosphorus and lower for iron in treatment F than treatment C (P≤0.05 and P≤0.02. respectively). The copper concentration in yolk and albumen was higher in treatment C than treatment F (P<0.01 and P≤0.03, respectively). Besides a few overall interactions, the AIA and ATD of copper and manganese were lower in H+M group than R+M group (P≤0.05). The ATD of iron was higher in the M+C group compared to the M+F group (P<0.01), whereas the albumen zinc concentration was higher in the E+C group than E+F group (P < 0.01). In conclusion, the feed produced by hammer mill had negative effects on AIA and ATD for trace elements in particular, but mineral concentrations in egg contents were mostly comparable for all treatments. Therefore, milling methods, thermal treatment, and particle sizes used in the present study can be used for layer feed formulation without negatively affecting egg quality.

Feed supplemented with organic acids does not affect starch digestibility, nor intestinal absorptive or secretory function in broiler chickens.

The current study aimed to determine the impact of acidified feed on apparent ileal starch digestibility, intestinal transport and barrier function and intestinal glucose transporter expression. The experiment included a control group and a treatment group with broilers fed a standard diet without or with 1.5% of a commercial organic acid product (64% formic acid, 25% propionic acid, 11% water). Broilers were fed with the experimental diets from hatching until days 32-35. Starch digestibility was determined using 0.2% titanium dioxide as ingestible marker. Gene expressions of the intestinal sodium glucose transporter 1 (SGLT-1) and glucose transporter 2 (GLUT-2) were analysed using qPCR analysis. Additionally, SGLT-1 function and chloride secretion were analysed in Ussing chamber experiments. Jejunal samples were sequentially exposed to 10 mm glucose, 100 µm phloridzin, 100 µm histamine and 100 µm carbachol. Apparent ileal starch digestibility (±SEM) of the control group (97.5 ± 0.35%) and the acid-treated group (97.0 ± 0.59%) did not differ (p = 0.674). The mean tissue conductance of intestinal samples obtained from the control group and the treatment group was similar [10.6 mS/cm(2) (±0.68) and 9.4 mS/cm(2) (±0.80) respectively (p = 0.147)]. The mean short-circuit currents (ΔIsc ) of the samples exposed to glucose, phloridzin, histamine and carbachol did not differ (p > 0.05). Additionally, no differences in the expression of SGLT-1 and GLUT-2 could be observed (p = 0.942, p = 0.413). Based on this study, the consumption of feed supplemented with organic acids was not associated with effects on ileal starch digestibility and functional traits of jejunal tissues, indicating that these additives have no major impact on the small intestinal function in broilers.

The effects of different thermal treatments and organic acid levels on nutrient digestibility in broilers.

Poultry feed is a potential vector for pathogens. Heat processing and organic acid treatments may decontaminate feed and can affect bird performance as well as feed digestibility. The present study was performed to investigate the effect of different thermal treatments including pelleting (P), long-term conditioning at 85°C for 3 min (L), or expanding at 110°C (E110) and 130°C for 3 to 5 s (E130) without or with 0.75 and 1.5% organic acid supplementation (63.75% formic acid, 25.00% propionic acid, and 11.25% water) on performance, nutrient digestibility, and organ weights of broilers. In total, 960 one-day-old broiler chicks were randomly assigned to 8 replicates using a 3 × 4 factorial arrangement. Performance variables were determined, and the relative organ weights and ileal and total amino acid (AA) digestibilities were measured at d 35. The organic acid inclusion linearly improved feed efficiency in the first week (P ≤ 0.05). The acid inclusion levels and thermal treatments had no significant effect on the performance variables at later intervals of the growing period of the birds. The L group showed the lowest ileal AA and CP digestibility. The inclusion of organic acids had a quadratic effect on total and ileal digestibility of isoleucine (P ≤ 0.05), whereas it had no significant effect on the ileal digestibility of other AA and nutrients. The relative weights of the jejunum and small intestine were significantly higher in the E130 group compared with P and L (P ≤ 0.05). In conclusion, our study demonstrated that long-term heat conditioning can decrease ileal nutrient digestibility, whereas pelleting and expansion, independently of organic acid addition, seemed to have no negative impact on broiler performance and nutrient digestibilities. Moreover, adding a blend of organic acids to broiler diets had neither positive nor negative effects on nutrient digestibility and final broiler performance. This indicates the feasibility of short-term thermal treatment and acid supplementation for hygienization of broiler feed without negatively influencing performance.

Impact of thermal and organic acid treatment of feed on apparent ileal mineral absorption, tibial and liver mineral concentration, and tibia quality in broilers.

Minerals play an important role for growth and bone stability in broilers. Thermal treatment and inclusion of organic acids in feed may affect the mineral absorption and tibial quality in broilers. The study was conducted to investigate the effect of thermal processing of feed including pelleting (P), long-term conditioning at 85°C (L), and expanding at 130°C (E) without and with 1.5% of an acid mixture containing 64% formic and 25% propionic acid on the apparent ileal absorption (AIA) of calcium, phosphorus, magnesium, potassium, sodium, iron, copper, manganese, and zinc, their concentrations in liver and tibia, as well as various tibial quality parameters in broilers. In total, 480 one-day-old Cobb broiler chicks were assigned using a completely randomized design with a 3 × 2 factorial arrangement. The ileal digesta, liver, and tibia were collected at d 35. The AIA of calcium and sodium was improved in group E compared with L (P ≤ 0.02 and P ≤ 0.01). Group P and E showed higher AIA for potassium than L (P ≤ 0.01). Bone ash content was increased in group E compared with L (P ≤ 0.04). The BW to bone weight ratio was lower and tibial zinc content was higher in group P compared with E (P ≤ 0.05). Tibial iron content was higher in group L than E (P ≤ 0.03). Acid addition did not affect AIA, mineral content in tibia, or tibial quality parameters. Thermal and acid treatment did not affect mineral concentrations in the liver, except an inconsistent interaction effect for DM content and sodium (P ≤ 0.03 and P ≤ 0.04, respectively). In conclusion, long-term thermal treatment reduced AIA of some minerals compared with short-term thermal treatments, but had no impact on tibia composition. Acid inclusion had no effect on AIA of minerals and tibia quality. Thermal treatment and the use of organic acids can therefore be considered as safe with regard to their impact on bone development in broilers.

Effects of grinding method, particle size, and physical form of the diet on gastrointestinal morphology and jejunal glucose transport in laying hens.

Several studies illustrated that the structure of feed, i.e., the particle size, particle-size distribution, and the physical form of the diet, affects the avian gastrointestinal function and health leading to changes in productive performance. However, investigations concerning the effects of feeding differently processed diets on laying hens are limited and primarily concentrated on bird performance. The current study examines the effect of feed processing on the gastrointestinal morphology and on the jejunal glucose transport of laying hens. In 8 replicates, a total of 384 hens (Lohmann Brown) aged 20 wk were randomly allocated to 8 different groups and fed over a period of 21 d in a 3-factorial design. Diets differed in 1) grinding method, either hammer or roller mill; 2) physical form, either mash or expandate; and 3) particle size, either coarsely or finely ground. During the experimental trial, the laying performance of each feeding group was recorded daily and the feed intake and BW determined weekly. After slaughtering, the weights of the pancreas, proventriculus, gizzard, and small intestine were measured. Villus lengths and crypt depths of the duodenum, jejunum, and ileum were determined. The jejunal electrogenic glucose transport was studied in Ussing chambers. Hens that received mash instead of expandate had higher proventriculus (P = 0.011), gizzard (P < 0.001), and pancreas (P = 0.019) weights, whereas the feeding of coarsely instead of finely ground diets led to higher gizzard weights (P < 0.001). Mash-fed hens showed longer duodenal (P < 0.001) and shorter ileal villi (P = 0.047) and increased duodenal villus height-to-crypt depth ratios (P < 0.001) than those given the expandate. Mash-fed hens had higher glucose transport rates than expandate-fed hens (P < 0.001). In conclusion, the feeding of coarsely ground as well as mash diets had stimulating effects on the development of the gastrointestinal organs. Moreover, the feeding of mash influenced the intestinal microstructure of the epithelium that was accompanied by higher glucose transport capacities.

The effects of different thermal treatments and organic acid levels in feed on microbial composition and activity in gastrointestinal tract of broilers.

Thermal treatments of feed and organic acids are known to affect the gastrointestinal microbiota in chickens. The present study evaluated the effect of different thermal processes including pelleting (P), long-term conditioning at 85°C for 3 min (L), expanding at 110°C (E110), and 130°C for 3 to 5 s (E130) as well as organic acid (63.75% formic acid, 25.00% propionic acid, and 11.25% water) inclusion levels (0, 0.75, and 1.5%) on gastrointestinal microbiota in broilers. In total, 960 one-day-old chicks were randomly assigned to 8 replicates using a 3 × 4 factorial arrangement. At d 35, bacterial cell numbers in the crop, ileum, and cecum, and bacterial metabolites in the crop, gizzard, ileum, and cecum were determined. The inclusion of 1.5% organic acids increased cell numbers of all clostridial clusters in the crop. The organic acid supplementation increased the propionic acid concentration in the crop and gizzard and there was a decrease in lactic acid concentration. In the ileum, the 0% organic acid group had the highest numbers of Lactobacillus spp. and enterobacteria. Inclusion of 1.5% organic acids increased ileal acetate concentration. Increasing the feed processing temperature led to an increase of lactobacilli in the crop and ileum, whereas clostridia and enterobacteria seemed unaffected. Similarly, lactate concentrations increased in the ileum, but short-chain fatty acids remained identical. In the crop, an increase for acetate was found for the E130 group compared with all other thermal treatments. In conclusion, our study demonstrated that thermal treatments and organic acid supplementation to broiler diets more markedly influenced the bacterial status of the crop compared with the downstream segments and their effects decreased along the length of gastrointestinal tract. Whereas organic acids markedly modified bacterial composition and activity in the crop, expansion increased lactobacilli and lactate in the crop and ileum.

The levels of zearalenone and its metabolites in plasma, urine and faeces of horses fed with naturally, Fusarium toxin-contaminated oats.

Concentration profile of zearalenone (ZON) and its metabolites in plasma, urine and faeces samples of horses fed with Fusarium toxin-contaminated oats is described. In plasma, ß-zearalenol (ß-ZOL) was detected at high levels on day 10 of the study (3.21-6.24 µg/l). ß-Zearalenol and α-zearalenol were the major metabolites in urine. Zearalenone, α-ZOL and ß-ZOL were predominantly found in faeces. Zearalanone could also be detected in urine (1.34-5.79 µg/l) and faeces (1 µg/kg). The degree of glucuronidation was established in all sample types, approximately 100% in urine and plasma. Low per cent of glucuronidation (4-15%) was found in faeces samples. The results indicate the main conversion of ZON into ß-ZOL in horse. This finding could explain why horse is not susceptible to ZON in comparison with swine which produce α-ZOL as a predominant metabolite.

Dietary inclusion of feathers affects intestinal microbiota and microbial metabolites in growing Leghorn-type chickens.

Feather pecking in laying hens is a serious behavioral problem that is often associated with feather eating. The intake of feathers may influence the gut microbiota and its metabolism. The aim of this study was to determine the effect of 2 different diets, with or without 5% ground feathers, on the gut microbiota and the resulting microbial fermentation products and to identify keratin-degrading bacteria in chicken digesta. One-day-old Lohmann-Selected Leghorn chicks were divided into 3 feeding groups: group A (control), B (5% ground feathers in the diet), and C, in which the control diet was fed until wk 12 and then switched to the 5% feather diet to study the effect of time of first feather ingestion. The gut microbiota was analyzed by cultivation and denaturing gradient gel electrophoresis of ileum and cecum digesta. Short-chain fatty acids, ammonia, and lactate concentrations were measured as microbial metabolites. The concentration of keratinolytic bacteria increased after feather ingestion in the ileum (P < 0.001) and cecum (P = 0.033). Bacterial species that hydrolyzed keratin were identified as Enterococcus faecium, Lactobacillus crispatus, Lactobacillus reuteri-like species (97% sequence homology), and Lactobacillus salivarius-like species (97% sequence homology). Molecular analysis of cecal DNA extracts showed that the feather diet lowered the bacterial diversity indicated by a reduced richness (P < 0.001) and shannon (P = 0.012) index. The pattern of microbial metabolites indicated some changes, especially in the cecum. This study showed that feather intake induced an adaptation of the intestinal microbiota in chickens. It remains unclear to what extent the changed metabolism of the microbiota reflects the feather intake and could have an effect on the behavior of the hens.

Feather-pecking response of laying hens to feather and cellulose-based rations fed during rearing.

Recent studies in laying hens have shown that feather peckers eat more feathers than nonpeckers. We hypothesized that food pellets containing feathers would decrease the birds' appetite for feathers and thereby also decrease feather pecking. To separate the effect of feathers from that of insoluble fiber per se, additional control groups were fed pellets containing similar amounts of cellulose. Sixty (experiment 1) and 180 (experiment 2) 1-d-old Lohmann-Selected Leghorn birds were divided into 12 groups of 5 (experiment 1) and 15 (experiment 2) birds, respectively, and kept on slatted floors. During the rearing period, 4 groups each had ad libitum access to either a commercial pelleted diet, a pelleted diet containing 5% (experiment 1) or 10% (experiment 2) of chopped feathers, respectively, or a pelleted diet containing 5% (experiment 1) or 10% (experiment 2) of cellulose, respectively. In the consecutive laying period, all groups received a commercial pelleted diet. In experiment 1, feather pecking was recorded weekly from wk 5 to wk 16. In the laying period, observations were made in wk 18, 20, 22, 23, 24, 25, 26, 27, 28, and 30. In experiment 2, feather pecking was recorded weekly from wk 5 to 11, in wk 16 to wk 18, and in wk 20 and 21. At the end of the rearing period, plumage condition per individual hen was scored. Scores from 1 (denuded) to 4 (intact) were given for each of 6 body parts. The addition of 10% of feathers to the diet reduced the number of severe feather-pecking bouts (P < 0.0129) and improved plumage condition of the back area (P < 0.001) significantly compared with control diets. The relationship between feather pecking/eating and the gastrointestinal consequences thereof, which alter feather pecking-behavior, are unclear. Understanding this relationship might be crucial for understanding the causation of feather pecking in laying hens.

Cytotoxicity and metabolic stress induced by deoxynivalenol in the porcine intestinal IPEC-J2 cell line.

The digestive tract is a target for the Fusarium toxin deoxynivalenol (DON), a major cereal grain contaminant of animal and public health concern. Toxic effects of DON range from diarrhoea, vomiting and gastrointestinal inflammation to necrosis of several tissues. Following ingestion of contaminated food or feed, intestinal epithelial cells are exposed to a high concentration of ingested DON, potentially affecting intestinal functions. Pigs are considered to be the species most sensitive to DON toxicity. However, only few studies directly evaluated DON effects on porcine intestinal epithelial cells. Therefore, we used the porcine intestinal cell line (IPEC-J2) to assess short-term effects of DON on functional characteristics of the intestinal epithelial cells. The cytotoxic effect of DON on IPEC-J2 cells was evaluated by measuring the count of living cells and the activity of lactate dehydrogenase (LDH) released in the culture media at a DON concentration range from 0, 0.5, 2.5 and 10 µm. We demonstrated that DON at concentrations of 2.5 and 10 µm decreased significantly (p < 0.001) the cell count in a dose-dependent manner. At a concentration of 10 µm, DON caused cell damage, including rounding of cells, autolysis and cell loss from the monolayer. The mycotoxin, DON, increased LDH release into the culture medium compared with the control value. The alterations of LDH showed a good agreement with the decrease in cell count. Deoxynivalenol decreased the l-lactate concentration in the fluid supernatant of IPEC-J2 cells at 2.5 µm (p < 0.05) with a maximal effect at 10 µm of DON. To determine whether the altered lactate production may be linked to alterations of energy balance, we measured cellular ATP levels in IPEC-J2 cells. A significant decrease in ATP levels was seen at 48 h in a dose-dependent manner. It could be demonstrated that DON has a distinct cytotoxic effect on IPEC-J2 cells.