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The potential of a phytogenic premix (PP) based on ginger, lemon balm, oregano and thyme to stimulate the expression of cytoprotective genes at the broiler gut level was evaluated in this study. In particular, the effects of PP inclusion levels on a selection of genes related to host protection against oxidation (catalase [CAT], superoxide dismutase 1 [SOD1], glutathione peroxidase 2 [GPX2], heme oxygenase 1 [HMOX1], NAD(P)H quinone dehydrogenase 1 [NQO1], nuclear factor (erythroid-derived 2)-like 2 [Nrf2] and kelch like ECH associated protein 1 [Keap1]), stress (heat shock 70 kDa protein 2 [HSP70] and heat shock protein 90 alpha family class A member 1 [HSP90]) and inflammation (nuclear factor kappa B subunit 1 [NF-κB1], Toll-like receptor 2 family member B (TLR2B) and Toll-like receptor 4 [TLR4]) were profiled along the broiler intestine. In addition, broiler intestinal segments were assayed for their total antioxidant capacity (TAC). Depending on PP inclusion level (i.e. 0, 750, 1,000 and 2,000 mg/kg diet) in the basal diets, 1-d-old Cobb broiler chickens (n = 500) were assigned into the following 4 treatments: CON, PP-750, PP-1000 and PP-2000. Each treatment had 5 replicates of 25 chickens with ad libitum access to feed and water. Data were analyzed by ANOVA and means compared using Tukey's honest significant difference (HSD) test. Polynomial contrasts tested the linear and quadratic effect of PP inclusion levels. Inclusion of PP increased (P ≤ 0.05) the expression of cytoprotective genes against oxidation, except CAT. In particular, the cytoprotective against oxidation genes were up-regulated primarily in the duodenum and the ceca and secondarily in the jejunum. Most of the genes were up-regulated in a quadratic manner with increasing PP inclusion level with the highest expression levels noted in treatments PP-750 and PP-1000 compared to CON. Similarly, intestinal TAC was higher in PP-1000 in the duodenum (P = 0.011) and the ceca (P = 0.050) compared to CON. Finally, increasing PP inclusion level resulted in linearly reduced (P ≤ 0.05) expression of NF-κB1, TLR4 and HSP70, the former in the duodenum and the latter 2 in the ceca. Overall, PP inclusion consistently up-regulated cytoprotective genes and down-regulated stress and inflammation related ones. The effect is dependent on PP inclusion level and the intestinal site. The potential of PP to beneficially prime bird cytoprotective responses merit further investigation under stress-challenge conditions.

Mycotoxins are a crucial problem for poultry production worldwide. Two of the most frequently found mycotoxins in feedstuffs are deoxynivalenol (DON) and fumonisins (FUM) which adversely affect gut health and poultry performance. The current knowledge on DON and FUM effects on broiler responses relevant for gut detoxification, antioxidant capacity, and health is still unclear. The aim of this study was to assess a range of selected molecular intestinal biomarkers for their responsiveness to the maximum allowable European Union dietary levels for DON (5 mg/kg) and FUM (20 mg/kg) in broilers. For the experimental purpose, a challenge diet was formulated, and biomarkers relevant for detoxification, antioxidant response, stress, inflammation, and integrity were profiled across the broiler intestine. The results reveal that DON significantly (p &lt, 0.05) induced aryl hydrocarbon receptor (AhR) and cytochrome P450 enzyme (CYP) expression mainly at the duodenum. Moreover, DON and FUM had specific significant (p &lt, 0.05) effects on the antioxidant response, stress, inflammation, and integrity depending on the intestinal segment. Consequently, broiler molecular responses to DON and FUM assessed via a powerful palette of biomarkers were shown to be mycotoxin and intestinal site specific. The study findings could be highly relevant for assessing various dietary bioactive components for protection against mycotoxins.

Two hundred 10-d-old broiler chickens were used to study the effects of different dried olive pulp (DOP) inclusion rates on growth performance and meat quality. Broiler chickens were assigned to 4 experimental treatments (5 replicates of 10 broiler chickens each) for 32 d. The broiler chickens of each treatment were offered a different combination of grower (d 11 to 22; grower phase) and finisher (d 23 to 42; finisher phase) diets in terms of DOP content. The experimental treatments were: control (C), grower and finisher diets with no DOP; treatment 1 (T1), grower and finisher diets with 25 and 50 g DOP/kg, respectively; treatment 2 (T2), grower and finisher diets with 50 g DOP/kg; and treatment 3 (T3), grower and finisher diets with 50 and 80 g DOP/kg, respectively. Feed intake and body weight were recorded to calculate weight gain and feed conversion ratio (FCR). Fatty acid (FA) composition, oxidative stability, pH at 24 h post-mortem (pH24), color properties, cooking loss, and tenderness (as shear force) were determined in the breast muscle obtained from 2 broiler chickens/replicate pen of each treatment at d 42. The FCR was greater in T2 and T3 compared to C (P = 0.013) during the grower phase. During the finisher phase, FCR was greater in T3 when compared to C (P = 0.014), and to T1 and T2 (P = 0.031). The addition of DOP increased 18:1n-9 and total monounsaturated FA (P

The present work was part of a project intended to evaluate whether organic selenium (Se) has the potential to protect against toxic effects exerted by cadmium (Cd). For this reason, 300 as-hatched, one-day-old broiler chickens were randomly allocated in four dietary treatments with five replicate pens per treatment. Chickens in T1 treatment, were offered a diet supplemented with 0.3 ppm Se (as Se-yeast), without added Cd, in T2 treatment, they were offered a diet with 0.3 ppm Se and 10 ppm Cd, in T3 treatment, they were offered a diet with 0.3 ppm Se and 100 ppm Cd, in T4 treatment, chickens were offered a diet supplemented with 3 ppm Se and 100 ppm Cd. Cadmium was added to the diets in T2, T3, and T4 as CdCl2. On the fourth and sixth weeks, liver and breast samples were obtained from two broilers per replicate pen. Relative gene expression levels of catalase (CAT), superoxide dismutase 1 (SOD1) and 2 (SOD2), methionine sulfoxide reductase A (MSRA) and B3 (MSRB3), iodothyronine deiodinase 1 (DIO1), 2 (DIO2), and 3 (DIO3), glutathione peroxidase 1 (GPX1) and 4 (GPX4), thioredoxin reductase 1 (TXNRD1) and 3 (TXNRD3), and metallothionein 3 (MT3) were analyzed by real-time quantitative PCR in liver, whereas the fatty-acid (FA) profile of breast muscle was determined by gas chromatography. Broilers supplemented with 0.3 ppm Se could tolerate low levels of Cd present in the diets, as there were no significant changes in the breast muscle FA profile, whereas excess Cd led to decreased polyunsaturated fatty acids (PUFAs), and in particular n-6 PUFA. Furthermore, treatments mainly affected the messenger RNA (mRNA) expression of SOD2, TXNRD3, and MT3, while age affected CAT, MSRB3, DIO2, DIO3, GPX4, TXNRD1, and MT3. In conclusion, dietary Se may help against the negative effects of Cd, but cannot be effective when Cd is present at excessive amounts in the diet.

The aim of this work was to assess the effect of dietary viable or heat inactivated probiotic forms (PF) combined or not with avilamycin (AV) used as a growth promoter, on broiler growth performance, nutrient digestibility, digestive enzyme activities, and expression of immune response related genes.Depending on the type of PF (i.e., no addition, viable, inactivated) and AV addition (no/yes), 450 one-day-old Cobb male broilers were allocated in the following 6 treatments according to a 3 × 2 factorial arrangement with 5 replicates of 15 broilers each for 6 wk: CoN: diet without any addition; CoN+A: combination of CoN with AV; ViP: viable PF - no AV; ViP+A: combination of ViP with AV; InP: inactivated PF - no AV; InP+A: combination of InP with AV.There were no interactions (P > 0.05) for overall performance parameters. In contrast, PF or AV addition improved BW gain (PPF= 0.015; PAV

The probiotic form (PF) type and its dietary administration in combination or not with avilamycin (AV) were investigated for their effects on broiler gut microbiota and expression of genes relevant for gut barrier and gut homeostasis. Depending on PF type (i.e. no addition, viable, inactivated) and AV addition (no/yes), 450 one-day-old Cobb male broilers were allocated in 6 treatments (CON, CON + A, ViP, ViP + A, InP and InP + A) according to a 3 × 2 factorial arrangement with 5 replicates of 15 broilers each for 42 days. Significant interactions (PPF × AV ≤ 0.05) between PF and AV administration were shown for the ileal mucosa-associated bacteria, the caecal digesta Lactobacillus spp., the molar ratio of the sum of valeric, hexanoic and heptanoic acids and the gene expressions of ileal and caecal IgA and ileal claudin 1. Avilamycin suppressed ileal digesta Lactobacillus spp. (PAV

The aim of this study was to investigate the effect of reduced dietary energy (ME) and protein (CP) levels along with administration of a phytogenic feed additive (PFA) based on oregano, anise and citrus essential oils, on broiler growth performance, nutrient digestibility, meat and blood biochemical parameters and total antioxidant capacity (TAC). Depending on dietary ME and CP level down regulation compared to a corn-soybean meal basal diet A used as positive control, three diet types [A, B(=A-3%) and C(=A-6%)] were implemented. Depending on the inclusion or not of PFA at 125 mg/kg diet, 450 1-d old, male Cobb broilers were randomly allocated in six treatments according to a 3×2 factorial arrangement with 5 replicates of 15 broilers; A: diets formulated optimally to meet broiler nutrient requirements for maximizing protein content of meat for starter, grower and finisher growth periods; APh: A+PFA; B: suboptimal in ME and CP levels by 3%; BPh: B+PFA; C: suboptimal in ME and CP levels by 6%; CPh: C+PFA. Feed conversion ratio (FCR) was improved in birds fed diet A compared to diet C during the grower period (P D =0.021) and overall (P D =0.010). Phytogenic supplementation resulted in higher (P D×Ph =0.020) total tract apparent digestibility of fat in birds fed diet C compared to diet A. Birds fed diet A had higher (P D =0.001) plasma cholesterol, compared to birds fed diet C. In addition, birds fed diets A and B had higher (P D =0.002) breast protein content compared to C. Overall, PFA inclusion reduced cholesterol (P Ph =0.002) and increased plasma TAC (P Ph

A study was conducted to determine the effects of dietary crude glycerine (CG) on growth performance, gene expression of glycerine kinase (GK), nutrient digestibility, and litter quality in broiler chickens. A total of 400 one-day old broiler chickens were randomly assigned to 4 diets containing 0, 70, 140, or 210 g CG/kg with 5 replicate pens and 20 broiler chickens per pen. Diets were formulated by substituting CG for corn, on an equal apparent metabolizable energy (AMEn) basis, with similar crude protein and amino acid contents. Feed and water intake, weight gain, excreta moisture, litter score, and mortality were recorded weekly. The total tract apparent digestibility (TTAD) of nutrients and energy was determined at d 28, and GK expression was determined in liver homogenates at d 42. The overall feed intake and BW gain were affected quadratically ( P 0.001), with broiler chickens fed the diet with 70 g CG/kg diet showing the greater values, whereas feed conversion ratio and water intake increased linearly ( P 0.05 and 0.001, respectively) with increasing dietary CG. The linear increase ( P 0.01) in excreta moisture resulted in a linear reduction ( P 0.001) of litter quality with the increment of CG. At d 28, the TTAD of dry matter, organic matter, and nitrogen free extract were not affected; however, the dietary AMEn content tended to decrease ( P =0.07) when CG increased to 210 g/kg diet. Relative GK mRNA increased for CG inclusion up to 140 g/kg diet and reached a plateau thereafter, indicating a limiting capacity for dietary CG activation. In conclusion, dietary inclusion of CG up to 70 g/kg may have beneficial effects on growth performance of broiler chickens. Dietary inclusion up to 140 g CG/kg may be efficiently utilized, whereas greater inclusion (>140 g CG/kg) may impair growth of broiler chickens, reduce litter quality, and increase mortality.

A total of 400, as hatched, broilers were used to investigate the effect of increase of selenium and energy intake on thyroid hormone metabolism, growth and liver fatty acid profile. There were 5 replicates of 4 dietary treatments namely, TA (0.289mg Se per kg diet and adequate energy content), TB (0.583mg Se per kg diet and adequate energy content), TC (0.267mg Se per kg diet and 9% increase of energy content) and TD (0.576mg Se per kg diet and 9% increase of energy content). Diets were isonitrogenous. Zinc L-selenomethionine complex was used to increase Se content and corn oil was used to increase the energy content. The experiment lasted 42 days. Broiler growth performance was not significantly affected by dietary treatments. Liver glutathione peroxidase (GPx) activity increased (P

Context Phytogenic applications in animal nutrition currently attract worldwide scientific attention for their potential to contribute positively to sustainable and high-quality animal production. However, further understanding and substantiation of dietary phytogenic functions is required. Aims The inclusion level of a phytogenic premix (PP) comprising functional flavouring substances from ginger, lemon balm, oregano and thyme was studied for its effects on broiler growth performance, carcass traits, nutrient digestibility, liver and meat total antioxidant capacity (TAC), and lipid oxidation. The expression of genes for nutrient transporter proteins (SGLT1, GLUT2, PEPT1, BOAT and LAT1), for FABP2 involved in cellular fatty acid uptake and metabolism, and for the mTORC1 complex relevant for protein synthesis were profiled along the intestine. Methods One-day-old Cobb broiler chickens (n = 500) were assigned to four treatments with five replicates of 25 chickens each. Starter (1–10 days), grower (11–22 days) and finisher (23–42 days) basal diets were supplemented with four levels of PP inclusion as treatments: 0, 750, 1000 and 2000 mg/kg diet, termed control, PP750, PP1000 and PP2000. Feed and water were available ad libitum. Data were analysed by ANOVA, taking the treatment as fixed effect. Statistically significant (P ≤ 0.05) effects were further analysed and means were compared using Tukey’s HSD test. Polynomial contrasts tested the linear and quadratic effect of PP inclusion levels. Key results Growth performance responses were not improved significantly (P > 0.05) by PP inclusion level. However, carcass (P = 0.030) and breast meat yield (P = 0.023) were higher in PP1000 than in the control. In addition, PP1000 had higher (P = 0.049) apparent metabolisable energy than PP2000 and the control. Increasing PP inclusion level increased breast (P = 0.005), thigh (P = 0.002) and liver (P = 0.040) TAC. Breast and thigh meat TAC reached a plateau at PP1000, whereas liver TAC continued to increase linearly. Lipid oxidation in breast meat and liver was delayed linearly (P ≤ 0.05) with increasing PP inclusion level. Expression of genes SGLT1, GLUT2, PEPT1, BOAT and FABP2 were not affected by PP inclusion. However, PP inclusion affected the expression of LAT1 (P < 0.001) in jejunum and of mTORC1 in duodenum (P = 0.010) and ceca (P = 0.025). In particular, expression increased with increasing PP inclusion level in a linear and quadratic pattern depending on the intestinal segment. Conclusions Overall, PP inclusion at 1000 mg/kg diet improved carcass and breast yield, dietary available energy, and overall meat and liver TAC. Preliminary evidence was highlighted for effects of PP in promoting expression of genes relevant for muscle protein synthesis. Implications This study has contributed new information on effects of a phytogenic premix on broiler meat yield and antioxidant capacity, digestibility, absorption and metabolic functions, further supporting phytogenic benefits for broiler production.

The effects of inclusion levels of a phytogenic feed additive (PFA), characterized by menthol anethol and eugenol, on broiler growth performance, nutrient digestibility, biochemical biomarkers and total antioxidant capacity (TAC) of plasma and meat, as well as on the relative expression of selected cytokines, were studied in a 42-d experiment. A total of 225 one-day-old male Cobb broiler chickens were assigned into 3 treatments, with 5 replicates of 15 chickens each. Chickens were fed maize-soybean meal basal diets following a 3 phase (i.e., starter, grower and finisher) feeding program. Depending on PFA inclusion level, treatments were: no PFA (PFA-0), PFA at 100 mg/kg (PFA-100) and PFA at 150 mg/kg (PFA-150). Feed and water were available ad libitum. Feed conversion ratio (FCR) during finisher phase was improved quadratically (P

The aim of this study was to investigate the effect of dietary probiotic inclusion level on mucin composition (monosaccharide ratio), mucosal morphometry, mucus layer staining intensity, and mucus layer thickness along the broiler intestinal tract. One-day-old male Cobb broilers were administered maize-soybean meal basal (BD) diets for 42 d and depending on the feed additive used, broilers were allocated into the following 5 experimental treatments: control C (BD, no additive), treatment P1 (10(8) colony forming units of probiotic/kg of BD), treatment P2 (10(9) cfu of probiotic/kg of BD), treatment P3 (10(10) cfu of probiotic/kg of BD), and treatment A (2.5 mg avilamycin/kg of BD). Intestinal samples from duodenum, ileum, and cecum of 14- and 42-d-old broilers were collected and analyzed. Mannose (Man) decreased linearly with increasing probiotic level in duodenum (P=0.015) and ileum (P=0.042) of 14-d-old broilers. N-Acetyl-glucosamine and galactose decreased linearly (P=0.012 and P=0.001, respectively), while fucose increased linearly (P

The effect of a dietary phytogenic feed additive (PFA) inclusion level in mucin monosaccharide composition, mucosal morphometry and mucus histochemistry along the broiler intestinal tract was studied. Cobb male broilers (n = 525) were allocated into five experimental treatments that, depending on the type of addition in the basal diet (BD), were labeled as follows: C (BD based on maize–soybean meal with no other additions), E1 (80 mg PFA/kg BD), E2 (125 mg PFA/kg BD), E3 (250 mg PFA/kg of BD) and A (2.5 mg avilamycin/kg BD). Samples from duodenum, ileum and cecum of 14- and 42-day-old broilers were collected and analyzed. In 14-day-old broilers, treatments E2 and E3 had higher (P < 0.01) duodenal mannose than treatments C, E1 and A. Ileal mannose was lower (P < 0.05) in treatment C compared with PFA treatments, and ileal galactose (Gal) was higher (P < 0.01) in treatments E2 and E3 compared with C and A. Polynomial contrast analysis with respect to PFA inclusion level showed that in 14-day-old broilers there was a linear increase (P = 0.001) in duodenal mannose and a quadratic effect (P = 0.038) in duodenal N-acetyl-galactosamine with increasing PFA level. Ileal Gal and mannose increased linearly (P = 0.002 and P = 0.012, respectively) with PFA inclusion level. There were no significant differences between treatments in mucin monosaccharide molar ratios of 42-day-old broilers. However, increasing PFA inclusion level resulted in a linear decrease of ileal fucose (P = 0.021) and cecal N-acetylgalactosamine (P = 0.036). Experimental treatments did not differ (P > 0.05) regarding duodenal villus height (Vh), crypt depth (Cd) and Vh/Cd ratio, irrespective of broiler age and the intestinal segment examined. However, increasing dietary PFA inclusion level showed a pattern of linear increase of duodenal Vh/Cd ratio in 14-day-old broilers and ileal Vh in 42-day-old broilers (P = 0.039 and P = 0.039, respectively). Alcian Blue–Periodic Acid-Schiff (pH 2.5) staining of neutral and acidic mucins showed that the staining intensity of mucus layer in villi was fragment (i.e. tip, midsection and base) dependent, whereas in crypts it was dependent both on intestinal segment (i.e. duodenum, ileum and cecum) and fragment. Finally, mucus layer thickness did not differ (P > 0.05) between treatments, yet a pattern of linear increase (P < 0.05) with PFA inclusion level was observed in the duodenum of 42-day-old broilers. In conclusion, the dietary inclusion level of PFA modulated broiler intestinal mucin composition and morphology. Further studies are required to elucidate the physiological implications of such changes in host–microflora interactions.

The aim of this work was to evaluate the effect of three inclusion levels of a phytogenic feed additive (PFA) comprising a blend of essential oils from oregano, anise and citrus on broiler growth performance, nutrient digestibility and caecal microflora composition. Five hundred and twenty-five, 1-day-old, male Cobb broilers received a maize–soybean meal basal diet (BD) and depending on the type of addition were allocated in the following five experimental treatments for 6 weeks: BD–no additives (C), BD containing 80 mg PFA/kg diet (E1), BD containing 125 mg PFA/kg diet (E2), BD containing 250 mg PFA/kg diet (E3) and BD containing avilamycin at 2.5 mg/kg diet (A). Treatment A was used as a positive control due to the well-known function of avilamycin as an antimicrobial growth promoter in poultry. Overall broiler body weight gain (BWG) increased linearly (P=0.039) with increasing PFA level, however, the avilamycin treatment A did not differ (P≥0.05) from the PFA and C treatments. Overall feed intake (FI) decreased quadratically (P=0.046) with increasing PFA level, while the FI for treatment A did not differ from the rest of the treatments. The overall gain:feed ratio improved linearly (P n ) of experimental diets, respectively, with treatment E1 having the higher (P n (13.4 MJ/kg diet) and treatment A being not different from the four other treatments. On the other hand, the avilamycin treatment A had a significantly (P Lactobacillus (P=0.002), Bifidobacterium (P=0.001) and Gram positive cocci (P=0.007) concentration with increasing PFA level at 42 d old broilers. In addition, caecal coliforms at 14 d old broilers were significantly (P In conclusion, this small scale study provides additional evidence that phytogenic efficacy in broilers depends on the feed inclusion level used and the broiler growth period with most of the PFA overall beneficial effects seen mainly in the finisher growth period. Further work is warranted in order to evaluate phytogenic efficacy with different basal diets and under commercial production conditions.

The aim of the study was to evaluate how palygorskite supplemented in broiler diets affects growth performance, mortality, litter quality and feed technological characteristics. Day-old broilers (n = 192) were raised for 6 weeks and fed either a corn–soybean base diet with no added palygorskite, or the same diet with 1% m/m, or 10% m/m added palygorskite. Body mass, feed conversion ratio, water intake, litter score and excreta dry matter, total and non-protein nitrogen content were assessed. To test for any negative health effects of the additive, mortality was assessed and standard hematological analyses were performed. Hardness and durability of pellets were measured to determine pellet quality. The study revealed that hardness of pellets was improved by palygorskite suggesting that it may be used as an agglomerant. Data on mortality and hematology indicated that palygorskite was safe and tolerable. The luck of statistically significant differences on improvement of litter quality with palygorskite addition could be attributed to the small scale of the study and the low stress conditions.

The aim of this work was to investigate the effect of inclusion levels of a 5-bacterial species probiotic in broiler nutrition. Five hundred twenty-five 1-d-old male Cobb broilers were allocated in 5 experimental treatments for 6 wk. The experimental treatments received a corn-soybean coccidiostat-free basal diet and depending on the addition were labeled as follows: no addition (C), 10(8) cfu probiotic/kg of diet (P1), 10(9) cfu probiotic/kg of diet (P2), 10(10) cfu probiotic/kg of diet (P3), and 2.5 mg of avilamycin/kg of diet (A). Each treatment had 3 replicates of 35 broilers each. Treatment effects on broiler growth performance and biomarkers such as ileal and total tract nutrient digestibility, plasma Ig concentration, and cecal microflora composition were determined. Differences among treatments were considered significant when P < or = 0.05. Overall BW gain was significantly higher in treatment P1 (2,293 g) compared with P2 (2,163 g), C (2,165 g), and P3 (2,167 g), with A (2,230 g) being intermediate and not different from P1. Overall feed conversion ratio values were similar and significantly better for P1 (1.80) and A (1.80) compared with P2 (1.87), C (1.89), and P3 (1.92). Ileal apparent digestibility coefficients (ADC) of CP and ether extract were higher in A. Generally, treatments A and P1 showed an improved total tract ADC for DM, organic matter, ash, ether extract, and AME(n) values. The total tract ADC of CP was higher in P1, C, and P2. There were no differences between treatments regarding plasma Ig in 14- and 42-d-old broilers. Treatments P2 and P3 were effective at beneficially modulating cecal microflora composition. In particular, the lower cecal coliform concentration (log cfu/g of wet digesta) was seen in P2 (6.12) and P3 (4.90) in 14- and 42-d-old broilers, respectively, whereas at 42 d, P3 and P2 had the highest Bifidobacterium (8.31; 8.08) and Lactobacillus concentrations (8.20; 7.86), respectively. It is concluded that probiotic inclusion level had a significant effect on broiler growth responses, nutrient ADC, AME(n), and cecal microflora composition.

The dietary supplementation of Saccharomyces cerevisiae var. boulardii was evaluated in broilers challenged or not challenged with Salmonella Enteritidis (SE) using a 2 × 2 factorial arrangement. Depending on yeast inclusion at 0 (C) or 1 × 10⁹ cfu/kg diet (Y) and SE challenge (0 or log 6.3 cfu/bird) on d 15, the experiment had four treatments C, Y, C-SE, and Y-SE, respectively. Each treatment had seven replicate floor pens with 15 broilers. Growth performance responses were determined weekly and overall for the 5 week experimental period. Salmonella levels and prevalence in ceca, cloacae, and carcass skin were determined by culture procedures, while cecal microbiota was determined by real time PCR. Yeast supplementation had no effect (PY0.05) on growth performance. For the overall post SE-challenge period (i.e., wk 3 to wk 5), Salmonella reduced body weight gain (BWG) (PSE0.001), feed intake (FI) (PSE = 0.032), and the European production efficiency (EPEF) factor (PSE = 0.005). Broilers Y-SE had higher (P0.001) overall BW gain compared to C-SE ones. Overall mortality was 2.14% and did not differ (P0.05) between treatments. Reduced Salmonella levels in the cloacae (P = 0.014) and on the breast skin (P = 0.006) and lower prevalence on the neck skin (P = 0.007) were noted for treatment Y-SE compared to C-SE. Yeast supplementation did not have an effect (P0.05) on cecal microbiota composition at d 1 and d 21 post SE-challenge. On the contrary, SE-challenge reduced cecal levels of total bacteria (PSE = 0.002), E. coli (PSE = 0.006), Bifidobacterium spp. (PSE = 0.006), Bacteroides spp. (PSE = 0.010), and Clostridial populations belonging to cluster I and cluster XIVa, (PSE = 0.047 and PSE = 0.001, respectively) on d 1 post SE-challenge. At 21 d post SE-challenge, only the levels of cecal Lactobacillus spp. (PSE = 0.001) and Bifidobacterium spp. (PSE = 0.049) were reduced compared to the non SE-challenged groups. In conclusion, yeast supplementation in SE challenged broilers (Y-SE) was beneficial for growth performance and reduced Salmonella presence compared to C-SE ones. The disturbance of cecal microbiota balance by SE merits further investigation for potential implications in gut and overall bird health.

(1) The objective of this study was to determine whether the dietary inclusion of Trichosporon mycotoxinivorans (TRM) could suppress the detrimental effects of ochratoxin A (OTA) on the immune system of broiler chicks. (2) Six experimental treatments were tested in 300 1-d-old broiler chicks. Treatments included addition to a standard broiler ration of neither OTA nor TRM (Diet 1), OTA alone (500 microg/kg), OTA plus TRM at three inclusion rates (10(4) CFU/g of feed, 10(5) CFU/g, 10(6) CFU/g) and TRM alone at 10(5) CFU/g of feed. The ration was fed to chicks for 42 d. (3) Blood samples were collected at d 10, 20, 30 and 40 and macrophages and heterophils were isolated. The following variables were determined in macrophages and heterophils activated by phorbol myristate acetate (65 microM): cell viability, total cell-associated urokinase-plasminogen activator (u-PA), membrane-bound u-PA, free u-PA binding sites and superoxide production. (4) There was a decrease in the viability of macrophages and heterophils from chicks receiving OTA-contaminated feed compared to the viability of cells from control birds at d 40. Dietary TRM completely blocked the effect of OTA on cell viability; all three inclusion rates were equally effective. There was a decrease in total cell-associated and membrane-bound u-PA in macrophages and heterophils of chicks receiving OTA-contaminated feed compared to the corresponding values in control birds for heterophils at d 30 and 40 and for the macrophages at d 40. (5) Similarly, dietary TRM abolished the effect of OTA on total cell-associated and membrane-bound u-PA activity. All three inclusion rates of yeast were equally effective. Heterophils, but not macrophages, isolated from chicks receiving OTA-contaminated diet produced less superoxide anion compared to all other diet groups at d 30 and 40. (6) The immune system is a primary target of OTA toxicity in broilers: several functional properties of macrophages and heterophils were depressed in chicks fed OTA-contaminated feed. There was a delay of 30d before the immunosuppressive effect became apparent. The dietary inclusion of TRM completely blocked the detrimental effects of OTA on several immune properties in broilers.

Near infrared spectroscopy (NIRS) is widely used in the flour milling industry for rapid determination of moisture and protein in wheat. However, these measurements give little indication of the nutritive value of wheat when fed to poultry or pigs. Accurate estimates of nutritive value require specialist facilities and are time-consuming and costly. Accordingly, prediction from chemical or NIRS measurements would be of some considerable benefit. In the current study 160 samples of wheat, representing 24 different varieties, were used to generate NIRS calibration equations for chemical, nutritive and agronomic characteristics. Predictions of chemical constituents in wheat were very accurate. Coefficients of determination (r2) were 0·94 for dry matter, 0·90 for crude protein, 0·97 for ash, 0·78 for starch and 0·98 for oil. True metabolizable energy in broiler chickens was predicted more accurately (r2 = 0·52 for adult birds, 0·74 for young birds) than apparent metabolizable energy (r2 = 0·45). Digestible energy (r2 = 0·17) and nitrogen digestibility (r = 0·22) in pigs were not predicted very accurately on a smaller subset (n = 33). Agronomic characteristics were predicted very accurately (r2 = 0·98 hardness, 0·80 bushel weight, 0·99 thousand-grain weight). Predictions of nutritive value of wheat from chemical or agronomic characteristics are very inaccurate, since coefficients of determination vary from zero to 0·25. It is concluded that NIRS can accurately estimate the chemical composition of wheat, but accurate prediction of nutritive value is reduced by animal variation. Nevertheless, NIRS is potentially more reliable for assessing nutritive value than chemical composition or agronomic characteristics.

The supplementation of a phytogenic feed additive (PFA) characterised by menthol and anethole was evaluated at three levels on broiler growth performance, nutrient digestibility, biochemical parameters, total antioxidant capacity of plasma, breast and thigh meat as well as on the relative gene expression of immune-related biomarkers. A total of 225 1-day-old male Cobb-500 were assigned into three treatments with five replicates of 15 chicks each. Wheat-soybean meal basal diets were formulated according to a three-phase (i.e. starter, grower and finisher) feeding program. Dietary treatments were: no PFA, PFA at 100 mg/kg diet and PFA at 150 mg/kg diet. Feed and water were available ad libitum. Performance parameters were monitored weekly and all other biological responses were determined at 42 days of broiler age. Increasing PFA level increased (P = 0.044) bodyweight gain at finisher period, decreased quadratically (P = 0.035) overall feed intake, and quadratically improved (P = 0.024) overall feed conversion ratio. Moreover, increasing PFA level increased plasma total antioxidant capacity linearly (P = 0.001) whereas linearly decreased (P = 0.005) triglyceride concentration. Thigh meat cholesterol decreased linearly (P = 0.016) with increasing PFA level. Expression of pro-inflammatory cytokine IL-2 in caecal tonsils increased quadratically (P = 0.046) with increasing PFA level. In conclusion, PFA inclusion at 100 mg/kg diet affected positively performance whereas a stronger improvement mainly in plasma total antioxidant capacity and triglyceride as well as in meat cholesterol was noted for the 150 mg/kg diet level. Inclusion of PFA resulted in increasing pro-inflammatory biomarker IL-2 at local caecal level.

The effect of dietary acidifier (AC) supplementation in combination or not with avilamycin (AV) was evaluated on broiler performance, nutrient digestibility, gizzard pH, activity of digestive enzymes and relative expression of cytokines. A 2 × 2 factorial experimental design with inclusion of AC (0 and 1 g/kg of diet) and AV (0 and 2.5 mg/kg of diet) as the main factors was implemented. Subsequently, 544-day-old male Cobb broilers were allocated in four treatments (i.e. C – no additions, AC; AV and ACAV), each having eight replicates of 17 broilers, for 6 weeks. Overall bodyweight gain (BWG) was improved (PAC = 0.035) by AC addition. BWG and feed conversion ratio were improved (P ≤ 0.05) by AV addition in all growth periods and overall. Dry matter, organic matter digestibility and energy retention were improved by AC (PAC = 0.050, PAC = 0.045 and PAC = 0.020, respectively), or AV (PAV = 0.018, PAV = 0.013 and PAV = 0.012, respectively). In addition AV supplementation improved digestibility of ether extracts (PAV = 0.022) and crude protein (PAV = 0.042). Pancreatic trypsin activity was lower in AC (PAC = 0.027) or AV (PAV ≤ 0.001) supplemented diets. An AC × AV effect on gizzard pH (PAC × AV = 0.034) was noted. Expression of interferon-γ (PAV = 0.010), interleukin (IL) 18 (PAV = 0.048) and inducible nitric oxide synthase 2 (PAV = 0.035) in spleen were downregulated by AV. An upregulation of IL10 (PAC × AV = 0.018), IL18 (PAC × AV = 0.002) and IL22 (PAC × AV = 0.030) in the caecal tonsils was shown for the combined ACAV supplementation. In conclusion, dietary AC supplementation improved performance, nutrient digestibility and energy retention, irrespective of AV inclusion. This study has provided evidence for potential links between digestive and immune function indices with growth performance improvements.

This work was part of a project designed to assess whether organic selenium (Se) can protect against the toxic effects of cadmium (Cd). A total of 300 1-day-old, as hatched, broilers were randomly distributed in four dietary treatments with five replicate pens per treatment. In T1 treatment, broilers were fed a diet with 0.3 mg/kg added Se, as Se-yeast, without added Cd; in T2, broilers were fed a diet with 0.3 mg/kg Se and 10 mg/kg Cd; in T3, broilers were fed a diet with 0.3 mg/kg Se and 100 mg/kg of Cd; and in T4 treatment broilers were fed a diet with 3 mg/kg Se and 100 mg/kg Cd. The Cd was added to diets T2, T3 and T4 as CdCl2. On the 4th and 6th week, two broilers per replicate pen were killed in order to obtain whole blood, liver, kidney and breast samples. Body mass, feed conversion ratio and mortality were assessed and haematological analyses were performed. Se and Cd levels in tissues were analysed by inductively coupled plasma mass spectrometry. Broilers supplemented with 0.3 mg/kg Se can tolerate low levels of Cd added to the diets, as there were no significant negative effects on the examined performance parameters, whereas addition of excess Cd led to an impairment of broilers' performance. Mortality of broilers did not differ between the four dietary treatments at any interval point or the whole period. The examined haematological parameters such as haematocrit, total blood protein concentration, and leukocytes types ranged within physiological values, revealing no negative health effects after simultaneous Cd and Se addition. The present study indicated that Se can help against the negative effects of Cd, but cannot counteract all of its negative effects.

Three dietary combinations of probiotics and phytogenics administered sequentially or continuously were assessed for their effects on broiler performance, nutrient digestibility, caecal microbiota composition, volatile fatty acid (VFA) pattern and plasma total antioxidant capacity (TAC). One-day-old Cobb male broilers (n = 525) were allocated to five experimental treatments for 42 days. Each treatment had three replicates of 35 broilers each. Depending on the time-frame of sequential or continuous addition in the basal diet (BD) of the probiotics (108 CFU/kg BD) and phytogenics (125 mg/kg BD), experimental treatments were: control (no additions, Days 1–42); PE1, probiotic Days 1–14 and phytogenic Days 15–42; PE2, probiotic Days 1–28 and phytogenic Days 29–42; PE3, probiotic and phytogenic continuously (Days 1–42); and A (2.5 mg avilamycin/kg diet, Days 1–42). There was no loss of probiotic viability upon mixing with the phytogenic for up to 7 days. Overall bodyweight gain was higher (P = 0.025) in the control and PE1 than PE2 and PE3, whereas Treatment A was intermediate and not different from the rest. Overall feed intake in the control was the highest (P = 0.003). Treatments PE1, PE2 and PE3 had better (P = 0.004) overall feed conversion ratio (FCR) than the control. The FCR in PE1 and PE3 did not differ from A, which had the best FCR. Mortality did not differ among treatments. Nutrient digestibility and caecal microbiota composition did not differ among treatments. However, differences (P ≤ 0.05) in caecal VFA pattern were noted, with the control having the lowest acetate molar ratio as well as the highest sum of valeric, hexanoic and heptanoic acids. Plasma TAC in the control was lower than in PE3, PE1 and PE2 at Day 14 (P < 0.001) and PE1 (P = 0.003) at Day 42. The concept of sequential or throughout probiotic and phytogenic administration showed promising results regarding feed efficiency and plasma TAC.

The effect of the dietary inclusion level of a three-species probiotic on broiler performance, nutrient digestibility, caecal microbiota composition and volatile fatty acid (VFA) pattern was evaluated. Day-old Cobb broilers (n = 448) were allocated in four treatments for 6 weeks. Each treatment had four replicates (two per gender) of 28 broilers each. Depending on the type of addition per kg basal diet, treatments were C (no other addition), PL (108 colony forming units of probiotic), PH (109 colony forming units of probiotic) and A (2.5 mg avilamycin). Overall bodyweight gain was better (P = 0.002) in PL and PH than in the control (2082 g) by 8.7% and 7.5%, respectively, while treatment PL did not differ from A (2341 g), which showed the highest bodyweight gain. The ileal and total-tract apparent digestibility of DM and the apparent metabolisable energy content corrected for N improved linearly (P ≤ 0.05) with the probiotic level. Fluorescent in situ hybridisation analysis showed caecal Bifidobacterium levels to increase linearly (P = 0.006) with the probiotic level. Probiotic administration resulted in altered caecal VFA patterns compared with the control. Gender effects (P ≤ 0.05) were noted for caecal levels of C. histolyticum group, Bacteroides fragilis group and Streptococcus spp., while interactions (P ≤ 0.05) of treatment with gender were seen for Bifidobacterium and all VFA components, except for acetate. In conclusion, beneficial effects on bodyweight gain, DM digestibility, apparent metabolisable energy content corrected for N, caecal Bifidobacterium levels and VFA patterns were noted with both probiotic inclusion levels.

The aim of this work was to investigate the efficacy of a new multibacterial species probiotic in broiler nutrition. The probiotic contained 2 Lactobacillus strains, 1 Bifidobacterium strain, 1 Enterococcus strain, and 1 Pediococcus strain. Four hundred 1-d-old male Cobb broilers were allocated in 4 experimental treatments for 6 wk. The experimental treatments received a corn-soybean basal diet and were as follows: "control," with no other additions; "probiotic in feed and water," (PFW) with probiotic administered at 1 g/kg of feed for the whole period and in water on scheduled intervals during the first 4 wk; "probiotic in feed," (PF) with probiotic in feed as in PFW; and "antibiotic," (AB) with addition of avilamycin at 2.5 mg/kg of feed. Salinomycin Na was used as a coccidiostat. Each treatment had 5 replicates of 20 broilers. Treatment effects on parameters of broiler performance and cecal microbial ecology were determined. Broiler BW, feed intake, and feed conversion ratio were determined on a weekly and overall basis. Cecal microflora composition, concentration of volatile fatty acids, and activities of 5 bacterial glycolytic enzymes (alpha-galactosidase, beta-galactosidase, alpha-glucosidase, beta-glucosidase, and beta-glucuronidase) were determined at the end of the experiment. Overall, treatment PFW displayed a growth-promoting effect that did not differ from AB. Overall, feed conversion ratio in treatment AB was significantly better (P < or = 0.01) than the control treatment, whereas treatments PFW and PF were intermediate and not different from AB. Concentrations of bacteria belonging to Bifidobacterium spp., Lactobacillus spp., and gram-positive cocci were significantly (P < or = 0.05) higher in treatments PFW and PF compared with the control and AB treatments. Treatments PFW and PF had significantly higher specific activities of alpha-galactosidase and beta-galactosidase compared with the control and AB treatments. In conclusion, probiotic treatment PFW displayed a growth-promoting effect that was comparable to avilamycin treatment. In addition, treatments PFW and PF modulated the composition and, to an extent, the activities of the cecal microflora, resulting in a significant probiotic effect.