Improving the bioavailability of manganese and meat quality of broilers by using hot-melt extrusion nano method.

1. Mineral excretion is an issue in the poultry industry. The use of micro minerals in nano form can increase bioavailability and decrease excretion rate. However, information concerning the bioavailability of nano manganese (Mn) in broiler chicks is limited.2. This experiment studied the influences of hot-melt extrusion (HME)-processed manganese sulphate on body weight gain, Mn bioavailability, nutrient digestibility and meat quality in broiler chicks fed a corn-soybean meal-based diet as a starter and grower phase. A total of 700 birds (Ross 308, 1-day-old) were randomly placed in 35 cages (20 birds per cage). The broiler chicks were fed one of seven experimental diets, which consisted of a control (without supplemental Mn), different levels of MnSO4 (IN-Mn60; 60, 120, and 200 mg/kg), or HME MnSO4 (HME-Mn; 60, 120, and 200 mg/kg).3. There was an increased serum Mn content in broilers fed diet supplemented with HME-Mn. In the grower phase, increased dietary Mn levels elevated the concentrations in the serum, liver, and tibia. There were increases in the excreta Mn content of broilers fed increasing levels. The supplementation of HME-Mn showed a lower percentage of abdominal fat compared with the IN-Mn treatment diets. Supplementation with HME-Mn decreased intramuscular fat compared with the diets supplemented with IN-Mn. The supplementation of HME-Mn decreased the thiobarbituric acid reactive substances (TBARS) at d 6 of age. The HME-Mn source showed a greater decrease in TBARS compared with the IN-Mn treatment.4. In conclusion, HME processing increased bioavailability and could be used as an environmentally friendly method to facilitate lower levels of Mn in the diet of broiler chickens.

Processing diets containing corn distillers' dried grains with solubles in growing broiler chickens: effects on performance, pellet quality, ileal amino acids digestibility, and intestinal microbiota.

The present study investigated the effects of feed form and distillers' dried grains with solubles (DDGS) on growth performance, nutrient digestibility, and intestine microbiota in broilers. A total of 720 broilers (Ross 308; average BW 541 ± 6 g) was randomly allotted to 6 treatments on the basis of BW. There were 6 replicates in each treatment with 20 birds per replicate. Birds were fed 3 different feed forms (mash, simple pellet, and expanded pellet) and DDGS (0 or 20% of diet) in a 3 × 2 factorial arrangement. Simple pellet (SP) and expanded pellet (EP) fed birds showed an increase in BW gain (P < 0.05). The interaction between feed processing and DDGS level was observed on pellet hardness (P < 0.01). The lowest (P < 0.01) pellet durability index (PDI) and hardness were observed in the diet with DDGS. Values for PDI and hardness were higher for EP compared with SP (P < 0.01). Simple pellet decreased ileal digestibility of CP compared to mash feed. The inclusion of DDGS decreased the digestibility of CP, and tended to decrease digestibility of DM (P = 0.056) and gross energy (P = 0.069). Expanded pellet feeding decreased (P < 0.05) the ileal digestibility of isoleucine, lysine, methionine, phenylalanine, threonine, cysteine, and glutamine compared with mash diet. Processed feed increased (P < 0.01) pH in the gizzard and duodenum; however, processing decreased pH in ileum. The addition of DDGS to the diet reduced pH in the duodenum. The population of Lactobacillus spp. was lower in the duodenum of birds fed the EP diet compared to the mash diet. Processed feed increased the colonization of Clostridium spp. in the gizzard. These results indicated that SP and EP in broiler diet had a potential to improve BW gain, but EP compromised amino acid digestibility. In addition, DDGS supplementation (20%) decreased pellet quality and CP digestibility in broiler chickens; however, the growth performance and feed intake were not affected.

Effects of mannan level and ß-mannanase supplementation on growth performance, apparent total tract digestibility and blood metabolites of growing pigs.

The exogenous enzymes are less consistent in their effects as their beneficial effects depend upon the types and level non-starch polysaccharides (NSP) present in the diets. Therefore, exogenous enzymes should be selected on the basis of types and amount of the NSP in the pig diets. The objectives of the present experiments were to investigate the effects of dietary level of mannan and ß-mannanase supplementation on growth performance, apparent total tract digestibility (ATTD) of energy and nutrients, and blood metabolites of growing pigs. In Exp. 1, 96 barrows were randomly allotted to four treatments on the basis of BW. There were four replicates in each treatment with six pigs per replicate. The dietary treatments were a corn-soybean meal (SBM)-based control diet and three other diets consisted of the control diet supplemented with 400, 800 or 1600 U of ß-mannanase/kg diet. The final BW, average daily gain (ADG) and blood glucose increased (linear, P0.05) on the concentrations of blood total cholesterol, triacylglycerides and blood urea nitrogen. These results indicate that supplementation of ß-mannanase to low- or high-mannan diets have potential to improve the performance of growing pigs. In addition, palm kernel meal may partially replace corn and SBM without reducing pig performance if ß-mannanase is added to diet.

Bacteriophage cocktail and multi-strain probiotics in the feed for weanling pigs: effects on intestine morphology and targeted intestinal coliforms and Clostridium.

Two experiments were conducted to investigate the effects of dietary supplementation of bacteriophage cocktail, probiotics and a combination of these two supplements on performance and gut health of weanling pigs. In Experiment 1, 150 weaned piglets were randomly allotted to three treatments on the basis of BW. The dietary treatments included a basal diet supplemented with 0 (control), 1.0 and 1.5 g/kg bacteriophage cocktail. Pigs fed 1.0 and 1.5 g/kg bacteriophage product had greater (P<0.05) average daily gain (ADG), apparent total tract digestibility of dry matter from day 22 to 35, ileal Lactobacillus spp., villus height (duodenum and jejunum), and fewer coliforms (ileum) and Clostridium spp. (ileum). In Experiment 2, 200 weaned piglets were randomly allotted to four treatments. Dietary treatments included basal diet, basal diet supplemented with 3.0 g/kg fermented probiotic product (P), 1.0 g/kg bacteriophage cocktail (B) and combination of 1.0 g/kg bacteriophage cocktail and 3.0 g/kg fermented probiotic product. Pigs fed bacteriophage cocktail diets had greater (P<0.05) overall ADG, gain to feed ratio (G : F), fecal score from day 8 to day 21, and pigs fed bacteriophage cocktail diets had fewer coliforms (ileum) Clostridium spp. (ileum and cecum). Probiotics significantly increased G : F, colonization of Lactobacillus spp. in ileum. At day 35, bacteriophage treatment group showed greater (P<0.05) villus height of the duodenum, but a deeper crypt in duodenum. The present results indicate that the bacteriophage cocktail had a potential to enhance the performance and gut health of weanling pigs, however their combination with probiotics did not show an interaction.

Effects of dietary supplementation with Gynura procumbens (Merr.) on egg yolk cholesterol, excreta microflora and laying hen performance.

Abstract 1. The present study investigated the effects of dietary supplementation with Gynura procumbens on egg yolk and serum cholesterol and triglycerides, excreta microflora, laying performance and egg quality. 2. A total of 160 Hy-Line Brown layers (45 weeks old) were randomly assigned into 4 treatments on the basis of laying performance. Each treatment had 4 replicates with 10 birds each. 3. Dietary treatments were basal diet supplemented with 0 (control), 2.5, 5.0 and 7.5 g/kg diet G. procumbens during 56-d feeding period. 4. Serum (d 21, 42 and 56) and egg yolk (d 28, 42 and 56) cholesterol and triglycerides concentrations were linearly reduced with increasing dietary concentrations of G. procumbens. 5. Increasing dietary concentrations of G. procumbens linearly reduced the excreta total anaerobic bacteria (d 28), Clostridium sp. and Escherichia coli (d 28 and 56) populations. 6. Overall egg production and egg mass were linearly increased, and overall feed efficiency was linearly improved with increase in dietary G. procumbens. 7. Dietary increasing concentrations of G. procumbens linearly improved egg yolk colour (d 28 and 56) and breaking strength of eggs (d 56). 8. The results obtained in the present experiment indicate that dietary supplementation with G. procumbens could reduce the egg yolk cholesterol, suppresses harmful excreta microflora and improves layers performance.

An antimicrobial peptide-A3: effects on growth performance, nutrient retention, intestinal and faecal microflora and intestinal morphology of broilers.

1. The present study investigated the effects of dietary supplementation with an antimicrobial peptide-A3 (AMP-A3) on growth performance, nutrient retention, intestinal microflora and intestinal morphology of broilers. 2. A total of 320-d-old chicks (Ross 308, average BW 44.0 ± 3.4 g) were randomly allotted to 4 dietary treatments on the basis of initial body weight (BW). The dietary treatments were negative control (NC; basal diet), positive control (PC; basal diet + 15 mg avilamycin/kg diet) and AMP-A3 (basal diet supplemented with 60 or 90 mg/kg AMP-A3). The NC diet was considered as 0 mg/kg AMP-A3 treatment. Experimental diets were given in two phases: starter phase (d 0-21) and finisher phase (d 22-35). 3. The overall BW gain and retention of dry matter (DM), gross energy (GE; d 19-21) and crude protein (CP; d 19-21 and d 33-35) were greater in birds fed on the PC and 90 mg/kg AMP-A3 diets than in birds fed on the NC diet. Also, an increase in dietary AMP-A3 linearly improved BW gain and retention of DM, GE (d 19-21) and CP (d 19-21 and d 33-35). 4. Birds fed on the PC and 90 mg/kg AMP-A3 diets had fewer excreta coliforms (d 21 and d 35), total anaerobic bacteria (TAB) and Clostridium spp. (d 35) and ileum and caecum coliforms (d 35) than birds fed on the NC diet. In addition, birds fed on the diet supplemented with increasing levels of AMP-A3 had linearly reduced excreta TAB (d 35), Clostridium spp. and coliforms (d 21 and d 35) and ileum and caecum coliforms (d 35). 5. Birds fed on the PC and 90 mg/kg AMP-A3 diets had greater villus height of the duodenum, jejunum and ileum than birds fed on the NC diet. Moreover, birds fed on increasing levels of AMP-A3 diet had increased (linear) villus height of the duodenum, jejunum and ileum. 6. These results indicate that 90 mg/kg AMP-A3 has the potential to improve growth performance, nutrient retention and intestinal morphology and to reduce harmful microorganisms in broilers and can be used as a potential antimicrobial growth promoter.

Effects of exogenous enzyme supplementation to corn- and soybean meal-based or complex diets on growth performance, nutrient digestibility, and blood metabolites in growing pigs.

Two experiments were conducted to determine the effects of dietary supplementation of exogenous enzymes on growth performance, apparent total tract digestibility (ATTD) of energy and nutrients, blood metabolites, fecal VFA, and fecal ammonia-N in growing pigs (Sus scrofa) fed a corn (Zea mays L.)- and soybean [Glycine max (L.) Merr.] meal (SBM)-based diet. In Exp. 1, 240 growing barrows (initial BW: 55.6 ± 0.9 kg) were randomly allotted to 5 treatments on the basis of BW. There were 4 replicates in each treatment with 12 pigs per replicate. The 5 treatments consisted of a corn-SBM-based control diet and 4 additional diets were similar to the control diet, with the exception that 0.05% ß-mannanase (M), α-amylase + ß-mannanase (AM), ß-mannanase + protease (MPr), or α-amylase + ß-mannanase + protease (AMP) was added to the diets, which were fed for 28 d. Pigs fed the AM, MPr, or AMP diet had greater (P < 0.05) ADG than pigs fed the control diet. Pigs fed the AMP diet also had greater (P < 0.05) ADG than pigs fed the M, AM, or MPr diet. Pigs fed the AMP diet had greater (P < 0.05) G:F than pigs fed the control diet. The G:F of the pigs fed the M, AM, or MPr diet were not different (P > 0.05) from the G:F in pigs fed the AMP or control diet. The ADFI, ATTD of nutrients, blood metabolites, and fecal VFA and ammonia-N concentrations were not different among treatments. In Exp. 2, 192 growing barrows (initial BW: 56.9 ± 1.0 kg) were allotted to 4 treatments. There were 4 replicates in each treatment with 12 pigs per replicate. Pigs were fed a corn-SBM-based diet (CSD) or a complex diet (CD) that contained corn, SBM, 3% rapeseed (Brassica napus L.) meal, 3% copra (Cocos nucifera L.) meal, and 3% palm (Elaeis guineensis Jacq.) kernel meal. Each diet was prepared without exogenous enzymes or with 0.05% AMP and all diets were fed for 28 d. The ADG and G:F of pigs fed the CSD were greater (P < 0.05) than pigs fed the CD. However, the type of diet had no effect on the ATTD of nutrients, blood metabolites, or fecal VFA and ammonia-N, and there was no diet × enzyme interaction for any of the measured variables. Supplementation of diets with exogenous enzymes resulted in greater (P < 0.05) ADG, G:F, ATTD of DM, GE, and CP, and blood urea nitrogen (BUN) concentration. These results indicate that supplementation of 0.05% of AMP enzymes to a corn-SBM diet or a complex diet may improve the performance of growing pigs.

Effect of supplementation of multi-microbe probiotic product on growth performance, apparent digestibility, cecal microbiota and small intestinal morphology of broilers.

The present study investigated the effect of inclusion of multi-microbe probiotic product on growth performance, apparent digestibility of nutrients, cecal microbiota and small intestinal morphology in broilers. Four hundred days-old Ross chicks were randomly allotted to five treatments on the basis of body weight (BW). Each treatment had four replicates of 20 chicks in each. Experimental diets were fed in two phases, starter (day 0-21) and finisher (day 22-35). Dietary treatments were; basal diet without any antimicrobial (NC), basal diet added with 20 mg Avilamycin/kg of diet (PC), 10(7) cfu multi-microbe probiotic/kg of diet (P1), 10(8) cfu multi-microbe probiotic/kg of diet (P2), and 10(9) cfu multi-microbe probiotic/kg of diet (P3). Overall BW gain and feed conversion ratio were better (p < 0.05) for treatments PC, P2 and P3 compared with NC and P1, with P1 being better (p < 0.05) than NC. Overall feed intake in treatments PC, P1, P2 and P3 were greater (p < 0.05) than NC. Apparent digestibility of dry matter and crude protein were greater (p < 0.05) in treatments PC, P2 and P3 compared with NC, with P1 being intermediate and not different form NC, PC, P2 and P3. At d 21 and 35, treatments PC, P1, P2 and P3 showed lower (p < 0.05) cecal Clostridium and Coliforms count in relation to NC. Moreover, cecal Clostridium (d 21) and Coliforms (d 21 and 35) count were lower (p < 0.05) in treatment PC in relation to P1; with P2 and P3 being intermediate and not different from PC. However, there was no effect of dietary treatments on cecal total anaerobic bacteria and Bifidobacterium spp. count. The villus height of duodenum in treatment PC was greater (p < 0.05) than NC, with P1, P2 and P3 being intermediate. Villus height of ileum in treatment PC was greater (p < 0.05) than in treatments P1 and NC, whereas it remained comparable among treatments PC, P2 and P3. Villus height to crypt depth ratio of ileum was greater (p < 0.05) for treatment PC, P2 and P3 compared with that in P1 and NC. It is concluded that multi-microbe probiotic inclusion at 10(8) and 10(9) cfu/kg diet had beneficial effects on broilers growth performance, apparent digestibility of nutrients and intestinal morphology and can be used as replacement to antibiotics growth promoter in broiler nutrition.

Effect of supplementation of Bacillus subtilis LS 1-2 to broiler diets on growth performance, nutrient retention, caecal microbiology and small intestinal morphology.

Present study investigated the effect of dietary supplementation of Bacillus subtilis LS 1-2 on growth performance, apparent nutrient retention, caecal microbial population and intestinal morphology in broilers. Three hundred and twenty day-old Ross broiler chicks were randomly allotted to four treatments on the basis of BW in a randomized complete block design. Experimental diets were fed in two phases: starter (d 0-21) and finisher (d 22-35). Dietary treatments were basal diet supplemented with 0% (control), 0.15%, 0.30% and 0.45% B. subtilis LS 1-2. Supplementation of increasing levels of B. subtilis LS 1-2 showed linear improvement (P<0.05) in growth performance and apparent nutrient retention. At d 35, birds supplemented with increasing levels of B. subtilis LS 1-2 showed decrease in caecal Clostridium and Coliform count (linear, P<0.05). Moreover, supplementation of B. subtilis LS 1-2 increased (linear, P<0.05) villus height and villus height to crypt depth ratio in both duodenum and ileum. Results obtained in the present study indicate that B. subtilis LS 1-2 can be used as a growth promoter in broiler diets and can improve intestinal microbial balance and gut health of broilers.

Efficiency of inorganic and organic iron sources under iron depleted conditions in broilers.

A total of 240 d-old male Ross chicks (average BW 37·15 ± 0·49 g) were fed on an iron (Fe)-deficient semi-synthetic diet (45 mg Fe/kg) from d 1-7 post hatching. At d 7, all 240 chicks (average BW 140·15 ± 1·4 g) with depleted Fe-stores were randomly assigned to three treatments on the basis of BW to study the efficiency of dietary inorganic and organic iron (Fe) utilisation. Each treatment had 4 replicates with 20 birds in each. Dietary treatments were: maize-soyabean meal-based basal diet, containing 103 to 106 mg Fe/kg (control); and basal diets supplemented with an additional 80 mg/kg Fe either from an inorganic (FeSO4 · H2O, 28% Fe) or organic (ferrous methionine chelate, 10% Fe) source. The starter and finisher diets were fed from d 7 to 21 and d 21 to 35, respectively. Improved body weight gain and FCR during finisher phase and overall study period; and greater DM and CP retention, and excreta Fe excretion, at d 20 to 21 and d 34 to 35; were observed in birds fed on Fe supplemented diets when compared with birds fed on control diet. At d 35, the RBC, Hb, haematocrit, and Fe concentration in plasma, tibia and liver were higher in birds fed on Fe supplemented diets than birds fed on the control diet. Supplementation of Fe in organic form resulted in greater Fe concentration in the tibia and liver and less Fe excretion at d 34 to 35, when compared with birds receiving inorganic Fe. These results indicate the necessity to supplement Fe in the commercial diets of broilers; however, organic and inorganic sources of Fe supplementation at 80 mg/kg were equally effective in improving performance, nutrient retention and haematological indices. In addition, Fe supplementation through an organic source seems to be more efficient in depositing Fe in the haemopoietic organs (liver and tibia) of birds under Fe depleted conditions.

Effects of mannanase and distillers dried grain with solubles on growth performance, nutrient digestibility, and carcass characteristics of grower-finisher pigs.

Four experiments were conducted to determine the effects of dietary supplementation of corn distillers dried grain with solubles (DDGS) diets with mannanase on performance, apparent total tract digestibility (ATTD) of energy and nutrients, blood metabolites, and carcass characteristics of grower-finisher pigs. In Exp. 1, 96 grower pigs (initial BW, 57.6 kg), 6 pigs per pen and 4 pens per treatment, were fed corn-soybean meal-based diets containing 10% DDGS and 0, 200, 400, or 600 units (U) of mannanase/kg. The ADG and blood glucose increased (linear, P < 0.05) with increasing concentrations of dietary mannanase. Pigs fed diets containing increasing levels of mannanase had improved ATTD of DM and CP (quadratic, P < 0.05). In Exp. 2, 64 finisher pigs (initial BW, 92.7 kg) were allotted to 4 treatment groups with 4 pigs per pen and 4 pens per treatment. Pigs were fed corn-soybean meal-based diets containing 15% DDGS and 0, 200, 400, or 600 U of mannanase/kg. Linear increases (P < 0.05) in ADG, blood glucose, and ATTD of DM, GE, and CP were observed with increasing levels of dietary mannanase supplementation. In Exp. 3, 208 grower pigs (initial BW, 60.5 kg) were allotted to 4 treatment groups with 13 pigs per pen and 4 pens per treatment. Pigs were fed diets containing 0 or 10% DDGS and 0 or 400 U of mannanase/kg in a 2 x 2 factorial arrangement. An increase (P < 0.05) in ADG and blood glucose for pigs fed diets containing mannanase was observed. The ATTD of DM and CP (P < 0.05) was decreased with the inclusion of DDGS, whereas pigs fed the mannanase-supplemented diets had an increased (P < 0.05) ATTD of CP. In Exp. 4, 208 finisher pigs (initial BW, 86.5 kg), with 13 pigs per pen and 4 pens per treatment, were fed diets containing 0 or 15% DDGS and 0 or 400 U of mannanase/kg in a 2 x 2 factorial arrangement. The ADG and blood glucose increased (P < 0.05) when mannanase was included in the diets. The ATTD of DM (P < 0.05), GE (P < 0.10), and CP (P < 0.05) increased by the supplementation with mannanase in the diets of finisher pigs. The carcass characteristics and meat quality were not affected by the DDGS or mannanase inclusion. These results indicated that including 10 and 15% DDGS in conventional swine grower and finisher diets had no detrimental effects on growth performance or carcass characteristics. In addition, supplementation with 400 U of mannanase/kg to diets containing 10 and 15% DDGS fed to grower and finisher pigs may improve growth performance and the ATTD of CP.

Potato (Solanum tuberosum L. cv. Gogu valley) protein as an antimicrobial agent in the diets of broilers.

Two experiments were conducted to evaluate potato protein (PP, experiment 1) and refined PP (RPP, experiment 2) obtained from Gogu valley tubers as an antimicrobial agent in broiler diets. In both the experiments, 1-d-old male Ross 308 chicks were allotted to 5 treatments and performance, nutrient retention, and microbial populations in excreta and cecum were studied. Dietary treatments were as follows: basal diet (negative control, NC), basal diet with antibiotic (positive control, PC, 10 mg/kg of avilamycin), and low, medium, or high levels of PP (0.25, 0.50, and 0.75%, respectively, in experiment 1) or RPP (200, 400, and 600 mg/kg, respectively, in experiment 2). The overall gain and retention of DM (d 20 to 21) and CP (d 20 to 21 and d 41 to 42) were greater in birds fed PC and high PP diets than birds fed the NC diet. Population of total aerobic bacteria and coliforms was lowest in the cecum and excreta of birds fed the PC diet and highest in birds fed the NC diet. An increase in dietary PP linearly improved BW gain, feed intake, and feed conversion ratio during starter phase and overall BW gain. Also, there was linear improvement in retention of DM (d 20 to 21) and CP (d 20 to 21 and d 41 to 42) and reduced populations of total aerobic bacteria and coliforms in the cecum (d 42) and excreta (d 28 and 42) due to an increase in dietary PP. In the second experiment, the PC diet and diets with increasing levels of RPP had no effect on performance and nutrient retention. Birds fed the PC diet had the lowest microbial population in excreta and cecum, whereas the population of total aerobic bacteria and coliforms in excreta and cecum decreased (linear, P < 0.05) as the level of RPP was increased in the diet. These results suggest that both PP and RPP obtained from Gogu valley potato tubers have in vivo antimicrobial activity.

Potato (Solanum tuberosum L. cv. Gogu valley) protein as a novel antimicrobial agent in weanling pigs.

A total of 280 weaned pigs (Landrace x Yorkshire x Duroc) were used in a 28-d growth study to investigate the effect of feeding different levels of potato proteins on growth performance, nutrient digestibility, immune response, small intestinal morphology, and bacterial populations in feces and large intestine. Pigs (initially 6.42 +/- 0.74 kg of BW and 23 +/- 3 d of age) were randomly allotted to 5 treatments on the basis of BW, each treatment composed of 4 pens, each pen having 14 pigs. Dietary treatments included positive control (PC; basal diet + 150 mg/kg apramycin and 10 mg/ kg colistin sulfate); and potato protein (PP), consisting of the basal diet with 0, 0.25, 0.50, or 0.75% of potato protein. Diets were fed in 2 phases: phase I (d 0 to 14 postweaning) and phase 2 (d 14 to 28 postweaning). Potato protein was extracted from a value-added type of the new potato variety, Solanum tuberosum L. cv. Gogu valley, and was shown to have a minimum inhibitory concentration of 300 to 500 mug/mL. Performance of PC was compared with 0.25 to 0.75% PP, whereas linear and quadratic trends of increasing PP (0 to 0.75% PP) were tested. Over the 28-d trial, pigs fed the PC diets showed improved overall ADG (P < 0.05) and G:F (P = 0.090) compared with pigs fed PP, whereas increasing levels of PP linearly improved ADG (P < 0.05), ADFI (P = 0.052), and G:F (P = 0.098). The digestibility of DM and CP in both the phases was greater in PC than PP, and feeding of PP linearly improved the DM digestibility (P < 0.05) in phase II. The bacterial populations in the feces of pigs fed PC and PP were comparable, except for total bacteria and coliform bacteria in the feces at d 14 and 28, which were decreased in PC; and feeding of PP was effective in linearly reducing the populations of microbes in feces and contents of cecum, colon, and rectum. There was linear increase (P < 0.10) in skin-fold thickness in response to phytohemagglutinin with an increase in PP levels. Haemagglutinin titers on d 21 were greater (P = 0.054) in PC, and at d 28 the haemagglutinin titers were quadratically affected in pigs fed PP (P = 0.070). There was a trend toward a decrease in crypt depth (P = 0.068) and a greater villus height:crypt depth ratio (P = 0.082) of ileum in PC compared with PP. These results suggest that PP may be an alternative to medicated feed with antibiotics because it showed antimicrobial activity by effectively reducing the population of coliform bacteria and also improved the performance of weanling pigs.

Effects of supplementation of beta-glucans on growth performance, nutrient digestibility, and immunity in weanling pigs.

Two experiments were conducted to evaluate the efficacy of beta-glucan on growth performance, nutrient digestibility, and immunity in weanling pigs. In Exp. 1, 210 weanling pigs (6.38 +/- 0.92 kg of BW) were fed dietary beta-glucan (0, 0.01, 0.02, 0.03, or 0.04%) for 5 wk. In Exp. 2, 168 pigs (6.18 +/- 1.31 kg of BW) were fed no beta-glucan or antibiotics (T1), 0.02% beta-glucan (T2), only antibiotics (T3), or 0.02% beta-glucan with antibiotics (T4) for 8 wk. In Exp. 2, the antibiotics fed were apramycin and carbadox in phase I (0 to 2 wk) and carbadox and chlortetracycline in phase II (3 to 8 wk). During Exp. 2, the performance study was conducted for 5 wk, and the immune response was tested until 8 wk. In Exp. 1, there was a trend for a linear increase (P = 0.068) in ADG as the dietary beta-glucan concentration increased in the diet. The digestibilities of DM, GE, CP, ether extract, Ca, and P increased linearly (P < 0.05) in the beta-glucan-supplemented pigs. In Exp. 2, the overall ADG was greater (P < 0.05) in treatment T4 compared with the control group (T1). Also, except for P, this group showed greater (P < 0.05) nutrient digestibilities than the control group. In Exp. 2, at d 15, 24, and 46 antibody titers were measured by ELISA against Pasteurella multocida type A and D after vaccination with atrophic rhinitis, and they differed significantly (P < 0.05) with no particular trend. Flow cytometry was used to determine porcine lymphocyte subpopulations at 4 and 8 wk of Exp. 2. There was an increase in CD4 cells (P < 0.05) and a trend for an increase in CD8 cells (P < 0.10) at 8 wk in pigs fed the T2 diet compared with the other groups. Overall, increasing the dietary concentrations of beta-glucan did not improve ADG without antibiotic, and in weanling pigs antibiotics seem to be more effective in improving nutrient digestibilities and growth performance than beta-glucan.

Effects of supplementation of beta-glucan on the growth performance and immunity in broilers.

Two experiments were conducted to evaluate the efficacy of beta-glucan on commercial broilers. In experiment 1, one hundred and forty-four broiler chicks were employed in a 2x3 factorial design with cage and open floor housing with three levels of beta-glucan viz. 0%, 0.02% and 0.04%. In experiment 2, ninety-six broilers were used with 4 treatments: No beta-glucan and antibiotic (T1), beta-glucan 0.03% (T2), antibiotic (T3), and beta-glucan 0.03% + antibiotic (T4) for 34 d with 3 replicates of 8 chicks each in both studies. During experiment 1 there was no significant effect of the feeding system or the beta-glucan levels on the performance from 0 to 17 d but during 18-34 days birds housed on the open floor had significantly (p<0.0001) higher weight gain compared with those in cages. In experiment 2, no significant effect was noticed on the weight gains when the effect of beta-glucan, antibiotic or their interaction were tested. The retention of dry matter increased in both experiments with beta-glucan supplementation. The CD8 and TCR 1 cells were significantly higher in the 0.04% beta-glucan group at 42 days as compared with the control. It could be concluded that beta-glucan supplementation was beneficial for broilers.