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.

Dietary organic selenium addition and accumulation of toxic and essential trace elements in liver and meat of growing rabbits.

The effects of dietary organic selenium (Se) addition at 0.1, 0.5 and 2.5 mg/kg vs. an unsupplemented basal diet (BD) on the accumulation of some toxic and essential trace elements were studied in the liver and muscle tissues of growing rabbits. Dietary Se addition increased liver and muscle Se concentration linearly (P < .001), and decreased linearly Cd, As, Ni and Cr (P < .001) in liver, as well as As (P < .01) and Cd (P < .001) in muscle. Muscle Cu and Zn contents were significantly lower (P < .05) in rabbits fed 2.5 mg Se/kg diet compared to the other 3 groups. Selenium was negatively correlated with Cr, Ni, Cd and As (P < .01) in liver, and with Cu (P < .05) and Cd (P < .01) in muscle. In conclusion, dietary Se supplementation decreased the accumulation of toxic (Cd and As) and potentially toxic (Cr and Ni) trace elements in rabbits. However, at excessive quantities may negatively affect essential trace elements.

Effects of increasing dietary organic selenium levels on meat fatty acid composition and oxidative stability in growing rabbits.

The effects of dietary organic selenium (Se) addition at 0.1, 0.5 and 2.5mg/kg vs. an unsupplemented basal diet (BD) on performance, fatty acid (FA) composition and oxidative stability were studied in muscle tissue of growing rabbits. Muscle Se content increased (P<0.001) in a dose dependent manner with dietary Se inclusion. Saturated FA (SFA) were affected linearly (P<0.05) and quadratically (P<0.05) by dietary Se addition. Polyunsaturated FA (PUFA) increased linearly (P<0.01) resulting in a linear increase in the PUFA:SFA ratio (P<0.01) with dietary Se increment. Feeding 0.5mgSe/kg diet reduced malondialdehyde (MDA) and oxygen radical absorbance capacity (ORAC) values in the muscle, whilst 2.5mgSe/kg diet increased MDA concentrations and tended to increase ORAC values, likely indicating oxidative stress. In conclusion, dietary Se supplementation at 0.5mg/kg improves meat FA composition and oxidative stability, whereas at 2.5mg/kg may induce pro-oxidant effects.

Probiotic form effects on growth performance, digestive function, and immune related biomarkers in broilers.

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 < 0.001), FCR (PPF < 0.001; PAV < 0.001) and production efficiency factor (PPF= 0.001; PAV= 0.001).Significant (PPF×AV ≤ 0.05) interaction effects regarding ileal digestibility (IAD) of DM and total tract apparent digestibility (TTAD) of DM and ether extracts (EE) were noted. In addition, PF affected IAD and TTAD of CP (PPF < 0.001, PPF= 0.004, respectively). Inactivated PF increased (PPR= 0.024) lipase activity in jejunal digesta.At spleen level InP and ViP+A down-regulated TGF-ß4 (PPF × AV = 0.035) compared to CoN and ViP, whereas ViP+A up-regulated iNOS (PPF × AV = 0.022). An anti-inflammatory effect of live and inactive PF and/or AV addition at cecal tonsils was shown by iNOS down-regulation (PPF × AV= 0.015) compared to CoN. Furthermore, AV down-regulated IFN-γ (PAV= 0.002).In conclusion, viable probiotic, as well as inactivated probiotic alone or in combination with avilamycin, improved nutrient digestibility. All dietary additives affected growth performance positively and induced an anti-inflammatory response at cecal level.

Evaluation of yeast dietary supplementation in broilers challenged or not with Salmonella on growth performance, cecal microbiota composition and Salmonella in ceca, cloacae and carcass skin.

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 (PY > 0.05) on growth performance. For the overall post SE-challenge period (i.e., wk 3 to wk 5), Salmonella reduced body weight gain (BWG) (PSE < 0.001), feed intake (FI) (PSE = 0.032), and the European production efficiency (EPEF) factor (PSE = 0.005). Broilers Y-SE had higher (P < 0.001) overall BW gain compared to C-SE ones. Overall mortality was 2.14% and did not differ (P > 0.05) 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 (P > 0.05) 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.

The role of organic selenium in cadmium toxicity: effects on broiler performance and health status.

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.

Modulation of intestinal mucin composition and mucosal morphology by dietary phytogenic inclusion level in broilers.

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.

Dietary probiotic inclusion level modulates intestinal mucin composition and mucosal morphology in broilers.

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<0.001) with increasing probiotic feed inclusion level in 42-d-old broiler cecum, with treatment A not differing from treatment C (P≥0.05). Cecal villus height and crypt depth increased linearly (P=0.016 and P=0.003, respectively) with probiotic inclusion level, with treatment A having higher (P≤0.05) values only from treatment C. Mucus layer thickness increased linearly with probiotic inclusion level in duodenum at 14 d and 42 d (P=0.007 and P=0.030, respectively). Finally, mucus layer staining intensity was influenced (P<0.001) by villus fragment (i.e., tip, midsection, and base) but not from the treatment, age, and intestinal segment examined. As a conclusion, this study provides evidence that probiotic inclusion level affects intestinal mucin monosaccharide composition, mucus layer thickness, and intestinal morphology in broilers.

Supranutritional selenium level affects fatty acid composition and oxidative stability of chicken breast muscle tissue.

A total of 128 broilers were used to investigate the effect of selenium (Se) on fatty acid (FA) composition and oxidative stability of lipids in the breast muscle tissue. There were 4 replicates of 4 dietary treatments: T1 (basal diet with no added Se), T2 (T1 with 0.15 mg Se added per kg diet), T3 (T1 with 0.3 mg Se added per kg diet) and T4 (T1 with 3.0 mg Se added per kg diet). A yeast source was used for added Se. Breast muscle tissue was collected from two chickens per replicate pen for the determination of Se concentration by ICP-MS, FA profile by GC and lipid oxidation using thiobarbituric acid reactive substances method. Addition of supranutritional Se levels to chicken diets leads to the production of Se-enriched meat. Consumption of 100 g of breast meat from chickens fed diets supplemented with 0.15, 0.3 and 3 mg Se per kg of diet can provide 26, 41 and 220 µg of Se, respectively. Long-chain polyunsaturated fatty acids namely C20:3n-6, C20:4n-6, C20:5n-3, C22:5n-3 and C22:6n-3 increased linearly (p = 0.047, p < 0.001, p = 0.023, p = 0.003 and p = 0.002, respectively) as the Se inclusion levels in the diets increased. At slaughter, a linear decrease in lipid oxidation (p = 0.019) was observed with Se addition, possibly attributed to the antioxidant properties of Se. Addition of supranutritional Se to chicken diets, at levels well below those causing toxicity, leads to production of Se-enriched meat, protection of health-promoting long-chain FA like C20:5n-3 and C22:6n-3 and protection of meat quality from oxidation at day 1 after slaughter.

The role of selenium in cadmium toxicity: interactions with essential and toxic elements.

1. The study was part of a project designed to investigate if organic selenium (Se) can ameliorate the toxic effects of cadmium (Cd). The main objective of the present study was to investigate, in the chicken, the interactions between Se, Cd and the following elements: Sb, Ca, Cr, Co, Cu, Fe, Pb, Mg, Mn, Mo, Ni, V and Zn. 2. A total of 300 1-d-old chickens (broilers) were randomly distributed among 4 dietary treatments with 5 replicate pens per treatment. In T1, chickens were fed on a diet with 0·3 mg/kg added Se, without added Cd. In T2, chickens were fed on a diet with 0·3 mg/kg Se and 10 mg/kg Cd. In T3, chickens were fed on a diet with 0·3 mg/kg Se and 100 mg/kg of Cd added and in T4 treatment, chickens were fed on a diet with 3 mg/kg Se and 100 mg/kg Cd added. Se was added as Se-yeast. Cd was added as cadmium chloride (CdCl2). On d 28 and 42, two chickens per replicate pen were killed for collection of whole blood, liver, kidney and breast muscle samples. Samples were analysed by ICP-MS. The data were analysed using a multivariate linear model. 3. While low Cd concentrations in the diet led only to an increase of Cd concentration in the examined tissues, addition of high concentrations of Cd increased the concentration of Cd, Cu, Sb and V and decreased that of Se, Mn and Fe. Addition of high Se concentrations did not significantly reduce Cd concentration. 4. Prior to model application, correlations of 78 elements were noted, while after model application 39 correlations were noted. Most notably, Cd was correlated with Ca, Co, Cu and Mg, while Se was correlated with Mn. 5. The present study revealed several correlations between essential, probably essential and toxic elements illustrating the importance of the balance between pro-oxidants and antioxidants.

Caecum odd-numbered and branched-chain fatty acid composition in response to dietary changes in fattening rabbits.

The study aimed to describe the interactions between nutrition and caecal bacteria abundance using odd-numbered and branched-chain fatty acids (OBCFA). Following a 2 × 2 factorial design, 47 rabbits were fed diets with two levels of digestible fibre (DF, 180 vs. 260 g/kg DM) supplemented with soybean oil (SO, 20 g/kg) or not. At 77 days of age, fatty acid (FA) composition was determined in caecal contents. The microbial origin of OBCFA vs. dietary FA in caecal contents was illustrated by clustering of these FA in the loading plots of principal component analysis. The contribution of odd-numbered FA in the OBCFA pattern was increased (p < 0.05) for high DF diets, whereas that of branched-chain FA decreased (p < 0.05), indicating potential shifts in the relative abundance of Gram-negative and Gram-positive fibrolytic bacteria respectively. Soybean oil reduced the relative importance of OBCFA (p < 0.001) in total microbial FA; however, its effects appeared to depend on the readily available fermentable substrate, as indicated by the DF × SO interactions (p < 0.001). In conclusion, OBCFA may be potentially used as markers of caecum function, but further detailed studies are necessary to validate their use as diagnostic tools in rabbit nutrition.

Effects of probiotic inclusion levels in broiler nutrition on growth performance, nutrient digestibility, plasma immunoglobulins, and cecal microflora composition.

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.

Effects of a multi-species probiotic on biomarkers of competitive exclusion efficacy in broilers challenged with Salmonella enteritidis.

1. Probiotics are beneficial microbes that are currently considered as alternatives to antimicrobial growth promoters (AGP) in animal nutrition. In addition, they are purported to suppress pathogens in the gut via the concept of competitive exclusion (CE). The aim of this work was to evaluate the efficacy of a multistrain probiotic against Salmonella enteritidis (SE) in broilers. 2. Three hundred and four, one-day-old, male Cobb broilers were fed a corn-soybean basal diet and were allocated to four experimental treatments for 6 weeks. Three of the four treatments were challenged with SE. Treatments were: C- (Negative Control, no SE challenge), C+ (Positive control, SE challenge, no other additives), AB (SE challenge + Avilamycin used as AGP) and PFW (SE challenge + probiotic in feed and water). Morbidity, mortality, incidence of Salmonella positive broilers, cecal microflora composition and antibody response (IgA and IgG) in the blood and intestine were determined as biomarkers of probiotic CE efficacy against SE. 3. The three SE challenged treatments had a significantly higher morbidity compared to C- during the first 2 weeks of age, while there were no differences between treatments regarding mortality. Salmonella shedding was evidenced in 75 and 50% of the birds at 5 and 21 d post-challenge, respectively. Microbiological analysis of cecal digesta in 42-d-old broilers revealed that while broilers in treatment C+ were 100% Salmonella positive, the broilers in treatments PFW and AB were 50% positive and in addition they had lower Salmonella levels (CFU/g digesta) by 27 logs compared to C+. At the age of 42 d significantly higher IgA and IgG specific immune responses against SE were detected at systemic and at intestinal level only for the positive control treatment (C+). 4. In conclusion, the lack of significant levels of specific IgA and IgG against SE at systemic and intestinal level combined with the lower prevalence of SE positive broilers and the lower cecal SE levels in treatments AB and PFW compared to C+, suggest that treatments PFW and AB were efficacious at reducing SE.

Effect of dietary oregano oil supplementation on lamb meat characteristics.

The effect of dietary oregano essential oil supplementation on lamb meat characteristics was investigated. Eight male and eight female Chios lambs were divided into two equal groups. The first group was fed with the control diet consisting of concentrated feed and alfalfa hay, whereas the second group consumed the same diet, the only difference being that the concentrated feed was uniformly sprayed with oregano essential oil (1ml/kg). Duration of the experimental period was two months. No differences were observed after oregano essential oil supplementation in final body weight (kg), body weight gain (g) and carcass yield (%). Tenderness of longissimus thoracis muscle, expressed as sarcomere length and shear force value, was not influenced by the treatment, whereas pH and colour parameters (yellowness-redness) appeared to increase (P<0.05). Moreover, results showed that dietary incorporation of oregano essential oil exerted strong antioxidant effects retarding lipid oxidation (MDA formation) in meat during refrigerated and long-term frozen storage (P<0.001).

Evaluation of the efficacy of a probiotic containing Lactobacillus, Bifidobacterium, Enterococcus, and Pediococcus strains in promoting broiler performance and modulating cecal microflora composition and metabolic activities.

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.

Effect of vitamin E supplementation on lymphocyte distribution in gut-associated lymphoid tissues obtained from weaned piglets.

Fifteen piglets were used to determine the effect of vitamin E supplementation on the number of CD4-immunoreactive (CD4+) T-lymphocytes, CD8-immunoreactive (CD8+) T-lymphocytes and IgA-immunoreactive (IgA+) B-lymphocytes per follicle in the Peyer's patch of distal ileum and the mesenteric lymph nodes of weaned piglets. Piglets, following a 3-day adaptation period after weaning, were assigned to one of three experimental groups: control (no vitamin E supplementation), vitamin E supplementation of 100 mg/kg of diet and vitamin E supplementation of 300 mg/kg of diet. Supplementation of vitamin E lasted for a period of 36 days. The basal diet contained 80 mg alpha-tocopherol/kg of diet. All piglets were killed at day 39 after weaning and samples of the distal ileum and adjacent mesenteric lymph nodes were collected. The number of cells for each lymphocyte subset was counted in the Peyer's patch and the mesenteric lymph nodes follicles, in cryostat sections processed for immunohistochemistry. Results showed that vitamin E supplementation (300 mg/kg diet) of piglets caused an increase (P < 0.05) in the number of IgA+ B-lymphocytes in the Peyer's patch, but not in the mesenteric lymph nodes, compared with the corresponding values in control animals. Vitamin E supplementation had no effect (P > 0.05) on the number of CD4+ and CD8+ T-lymphocytes in the follicles of the Peyer's patch and the adjacent mesenteric lymph nodes. Thus, vitamin E had relatively minor effects on distribution of the major immunocompetent cells in the gut. The numbers of CD4+ and CD8+ T-lymphocytes as well as IgA+ B-lymphocytes per follicle were higher by 26-77% (P < 0.05) in the mesenteric lymph nodes than the corresponding values in the Peyer's patch.

The effect of two bovine beta-casein peptides on various functional properties of porcine macrophages and neutrophils: differential roles of protein kinase A and exchange protein directly activated by cyclic AMP-1.

The effects of two bovine beta-casein peptides on the urokinase plasminogen activator (u-PA) system and superoxide anion (SA) production by porcine macrophages and neutrophils activated by phorbol myristate acetate (PMA) were investigated. Macrophages and neutrophils were obtained from fourteen weaned piglets and were cultured in vitro for 24 h with or without one of two chemically synthesised peptides: tripeptide leucine-leucine-tyrosine (residues 191-193 of beta-casein) (LLY) and hexapeptide proline-glycine-proline-isoleucine-proline-asparagine (residues 63-68 of beta-casein). Following incubation, cells were stimulated with 80 microM-PMA. Total cell-associated u-PA, membrane-bound u-PA, free u-PA binding sites along with SA production were determined after stimulation with PMA. Both peptides suppressed the u-PA system and SA production of PMA-stimulated macrophages isolated from piglets during weeks 1-2 after weaning. Only the tripeptide LLY suppressed the u-PA system and SA production of PMA-stimulated neutrophils during the same time period. None of the peptides tested had any effect (P>0.05) on the u-PA system and SA production of PMA-stimulated macrophages and neutrophils isolated from the same piglets during weeks 5-6 after weaning. Thus, peptides are effective only in the early post-weaning period. Using cyclic AMP analogues that are highly specific activators of protein kinase A (PKA) or exchange protein directly activated by cyclic AMP-1 (Epac-1), we found that activation of PKA, but not Epac-1, was responsible for the downregulation of the u-PA system, whereas activation of PKA and/or Epac-1 was responsible for the downregulation of SA system in both macrophages and neutrophils.

Profiling of composition and metabolic activities of the colonic microflora of growing pigs fed diets supplemented with prebiotic oligosaccharides.

It is evident that quantitative information on different microbial groups and their contribution in terms of activity in the gastrointestinal (GI) tract of humans and animals is required in order to formulate functional diets targeting improved gut function and host health. In this work, quantitative information on levels and spatial distributions of Bacteroides spp, Eubacterium spp, Clostridium spp, Escherichia coli, Bifidobacterium spp and Lactobacillus/Enterococcus spp. along the porcine large intestine was investigated using 16S rRNA targeted probes and fluorescent in situ hybridisation (FISH). Caecum, ascending colon (AC) and rectum luminal digesta from three groups of individually housed growing pigs fed either a corn-soybean basal diet (CON diet) or a prebiotic diet containing 10 g/kg oligofructose (FOS diet) or trans-galactooligosaccharides (TOS diet) at the expense of cornstarch were analysed. DAPI staining was used to enumerate total number of cells in the samples. Populations of total cells, Bacteroides, Eubacterium, Clostridium and Bifidobacterium declined significantly (P < 0.05) from caecum to rectum, and were not affected by dietary treatments. Populations of Lactobacillus/Enterococcus and E. coli did not differ throughout the large intestine. The relative percent (%) contribution of each bacterial group to the total cell count did not differ between caecum and rectum, with the exception of Eubacterium that was higher in the AC digesta. FISH analysis showed that the sum of all bacterial groups made up a small percentage of the total cells, which was 12.4%, 21.8% and 10.3% in caecum, AC and rectum, respectively. This supports the view that in swine, the diversity of GI microflora might be higher compared to other species. In terms of microflora metabolic activity, the substantially higher numerical trends seen in FOS and TOS treatments regarding total volatile fatty acid, acetate concentrations and glycolytic activities, it could be postulated that FOS and TOS promoted saccharolytic activities in the porcine colon.

Use of Trichosporon mycotoxinivorans to suppress the effects of ochratoxicosis on the immune system of broiler chicks.

(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.