Chul-Ju Yang

Effects of Bacillus amyloliquefaciens as a probiotic strain on growth performance, cecal microflora, and fecal noxious gas emissions of broiler chickens

This experiment was conducted to investigate the effects of Bacillus amyloliquefaciens probiotic (BAP) as a direct-fed microbial on growth performance, cecal microflora, serum immunoglobulin levels, and fecal noxious gas emissions of broiler chickens. A total of 400 one-day-old broiler chicks (Ross 308) were randomly assigned to 1 of 5 treatment diets formulated to supply 0, 1, 5, 10, and 20 g/kg of BAP and were fed for 35 d. Each treatment had 8 replicate pens with 10 birds per replicate. On completion of the growth trial, fecal samples were collected, and ammonia (NH3) and hydrogen sulfide (H2S) emissions were measured. Increasing concentration of BAP had positive linear effect on the ADG of broilers (P < 0.05) throughout the experimental period, with the highest values being observed in broilers offered 20 g/kg of BAP. The ADFI increased linearly (P < 0.02) with the inclusion of BAP during the overall experimental period (d 0 to 35). Providing BAP had a negative linear effect on FCR from d 0 to 21 and d 0 to 35 (P < 0.01). Supplementation with BAP did not affect cecal Lactobacillus and Bacillus content, but exerted negative linear effect on cecal Escherichia coli (P < 0.05) with increasing the level of BAP in broiler diets. Additionally, BAP modified immune response of broilers by linearly increasing serum IgG and IgA (P < 0.01). Dietary BAP resulted in decreased fecal NH3 emissions at 0 (linear, P < 0.001), 3, 6, 12, 24, and 48 h of incubation (linear, P < 0.05; quadratic, P < 0.01). Supplementation of BAP exerted negative linear and quadratic effects on fecal emissions of H2S (P < 0.001) throughout the incubation period except at 48 h, and the optimum effect was found when BAP was provided at 5 g/kg of diet. Based on these results, Bacillus amyloliquefaciens could be suggested as a potential feed additive of broiler diets.

Effects of Resveratrol and Essential Oils on Growth Performance, Immunity, Digestibility and Fecal Microbial Shedding in Challenged Piglets

A study was conducted to evaluate the effects of resveratrol and essential oils from medicinal plants on the growth performance, immunity, digestibility, and fecal microbial shedding of weaned piglets. A total of 48 weaned piglets (8 kg initial weight, 28-d-old) were randomly allotted to four dietary treatments with 3 replications of 4 piglets each. The dietary treatments were NC (negative control; basal diet), PC (positive control; basal diet+0.002% apramycin), T1 (basal diet+0.2% resveratrol), and T2 (basal diet+0.0125% essential oil blend). All piglets were orally challenged with 5 ml culture fluid containing 2.3×108 cfu/ml of Escherichia coli KCTC 2571 and 5.9×108 cfu/ml Salmonella enterica serover Typhimurium. The PC group (p<0.05) showed the highest average daily gain (ADG) and average daily feed intake (ADFI) throughout the experimental period, although feed conversion ratio (FCR) was improved in the T1 group (p>0.05). Serum IgG level was increased in the T1 group, whereas TNF-α levels was reduced in the supplemented groups compared to control (p<0.05). The PC diet improved the dry matter (DM) digestibility, whereas PC and T2 diets improved nitrogen (N) digestibility compared to NC and T1 diets (p<0.05). Fecal Salmonella and E. coli counts were reduced in all treatment groups compared to control (p<0.05). Fecal Lactobacillus spp. count was increased in the T2 group compared to others (p<0.05). Dietary treatments had no significant effect on fecal Bacillus spp. count throughout the entire experimental period. Based on these results, resveratrol showed strong potential as antibiotic alternatives for reversing the adverse effects of weaning stress on growth performance, immunity and microbial environment in E. coli and Salmonella-challenged piglets.

Meat composition, fatty acid profile and oxidative stability of meat from broilers supplemented with pomegranate (Punica granatum L.) by-products

The effects of diets supplemented with four levels (0%, 0.5%, 1.0% and 2.0%) of pomegranate by-product (PB) on meat composition, fatty acid profile and oxidative stability of broiler meat were evaluated. The crude protein and moisture contents increased, whereas ether extract in breast and thigh meat and cholesterol in breast meat decreased in response to dietary PB supplementation (p<0.05). In breast and thigh meat, the sum of saturated fatty acids was lower, while the sum of mono-unsaturated and n-3 fatty acids were higher, alongside lower n-6/n-3 ratio in the 1.0% and 2.0% PB supplemented group (p<0.05). The TBARS values and pH of breast and thigh meat were reduced in the PB supplemented groups (p<0.05). Overall, the results presented herein indicate that supplementation of diets with up to 2% pomegranate by-products improved the meat composition, fatty acid profile and reduced lipid oxidation of broiler meat.

Comparison of Single and Blend Acidifiers as Alternative to Antibiotics on Growth Performance, Fecal Microflora, and Humoral Immunity in Weaned Piglets

The banning of the use of antibiotics as feed additive has accelerated investigations of alternative feed additives in animal production. This experiment investigated the effect of pure citric acid or acidifier blend supplementation as substitute for antibiotic growth promoters on growth performance, fecal microbial count, and humoral immunity in weaned piglets challenged with Salmonella enterica serover Typhimurium and Escherichia coli KCTC 2571. A total of 60 newly weaned piglets (crossbred, 28-d-old; average 8 kg initial weight) were randomly assigned to four dietary treatments in a completely randomized design. Dietary treatments included NC (negative control; basal diet), PC (positive control; basal diet+0.002% apramycin), T1 (basal diet+0.5% pure citric acid), and T2 (basal diet+0.4% acidifier blend). All piglets were orally challenged with 5 mL of culture fluid containing 2.3×108 cfu/mL of E. coli KCTC 2571 and 5.9×108 cfu/mL of S. typhimurium at the beginning of the experiment. The PC group showed the highest ADG and ADFI, whereas gain:feed was improved in the PC and T1 group (p<0.05). All dietary treatments showed significant reduction in fecal counts of Salmonella and E. coli, compared to NC (p<0.05), with PC being better than T1 and T2. Significant elevation in fecal Lactobacillus spp. counts was shown by treatments with T1, T2, and PC, whereas Bacillus spp. counts were increased by treatment with T1 and T2 compared to NC and PC diet (p<0.05). Serum IgG concentration was increased by T1 diet (p<0.05), whereas IgM and IgA were not significantly affected by any of the dietary treatments (p>0.05). From these above results, it can be concluded that, as alternatives to antibiotics dietary acidification with pure citric acid or acidifiers blend did not fully ameliorate the negative effects of microbial challenges in respect of growth performance and microbial environment, however improved immunity suggested further research with different dose levels.

Evaluation of probiotic strains for development of fermented Alisma canaliculatum and their effects on broiler chickens

The present study was conducted to select appropriate microbial strains for the development of fermented Alisma canaliculatum A. Br. et Bouche (FAC) feed additive and to examine their effects on broilers. In experiment 1, 16 strains of Lactobacillus acidophilus, Lactobacillus plantarum, Enterococcus faecium, Bacillus subtilis, Bacillus coagulans, and Saccharomyces cerevisiae from the Korean Collection for Type Cultures (KCTC) were evaluated. The strains were tested for their acid, bile, and heat tolerance levels. Among them, L. acidophilus KCTC 3111, E. faecium KCTC 2022, B. subtilis KCTC 3239, and S. cerevisiae KCTC 7928 were selected to produce FAC. For experiment 2, 140 Ross broiler chicks were allocated to four 5-wk-long dietary groups: NC (basal diet), PC (basal diet with 0.005% oxytetracycline), AC (basal diet with 0.5% A. canaliculatum rhizome powder), and FAC (basal diet with 0.5% FAC). Final BW and total BW gain were increased (P < 0.05) upon the addition of FAC, whereas feed conversion ratio improved (P < 0.05) in the supplemented groups compared with the NC group. Crude protein content increased and crude fat decreased (P < 0.05) in the breast meat of the FAC group compared with the AC and PC groups, respectively. Proventriculus and kidney relative weights of the FAC group differed (P < 0.05) from the AC group but not from the PC group. Lower (P < 0.05) thiobarbituric acid reactive substances value of thigh meat was observed in the FAC group compared with the other groups. The FAC diet increased (P < 0.05) α-linolenic acid and linoleic acid in meat. Alteration of these fatty acids led to increased levels of polyunsaturated fatty acid, polyunsaturated fatty acid /saturated fatty acid, n-3 and n-6 fatty acids, and decreased n-6/n-3 ratio in breast or thigh meat (P < 0.05). It is concluded that FAC confers high tolerance to acid, bile and heat; and beneficially affects growth, meat composition, oxidative stability, and fatty acid composition. The FAC may be a functional feed additive in broilers.

Effects of supplementation with green tea by‐products on growth performance, meat quality, blood metabolites and immune cell proliferation in goats

Forty-eight castrated male goats were used to determine the effects of feeding green tea by-products (GTB) on growth performance, meat quality, blood metabolites and immune cell proliferation. Experimental treatments consisted of basal diets supplemented with four levels of GTB (0%, 0.5%, 1.0% or 2.0%). Four replicate pens were assigned to each treatment with three goats per replicate. Increasing dietary GTB tended to linearly increase the overall average weight gain and feed intake (p = 0.09). Water holding capacity, pH and sensory attributes of meat were not affected by GTB supplementation, while cooking loss was reduced both linearly and quadratically (p < 0.01). The redness (linear; p = 0.02, quadratic; p < 0.01) and yellowness (quadratic; p < 0.01) values of goat meat were improved by GTB supplementation. Increasing dietary GTB quadratically increased protein and decreased crude fat (p < 0.05), while linearly decreased cholesterol (p = 0.03) content of goat meat. The proportions of monounsaturated fatty acid, polyunsaturated fatty acid (PUFA) and n-6 PUFA increased linearly (p < 0.01) and n-3 PUFA increased quadratically (p < 0.05) as GTB increased in diets. Increasing dietary GTB linearly increased the PUFA/SFA (saturated fatty acid) and tended to linearly and quadratically increase (p ≤ 0.10) the n-6/n-3 ratio. The thiobarbituric acid-reactive substances values of meat were lower in the 2.0% GTB-supplemented group in all storage periods (p < 0.05). Dietary GTB linearly decreased plasma glucose and cholesterol (p < 0.01) and quadratically decreased urea nitrogen concentrations (p = 0.001). The growth of spleen cells incubated in concanavalin A and lipopolysaccharides medium increased significantly (p < 0.05) in response to GTB supplementation. Our results suggest that GTB may positively affect the growth performance, meat quality, blood metabolites and immune cell proliferation when supplemented as a feed additive in goat diet.

Effects of Citrus junos by-products fermented with multistrain probiotics on growth performance, immunity, caecal microbiology and meat oxidative stability in broilers

Abstract 1. The present study was conducted to develop Citrus junos probiotics (CJP), using by-products of Citrus junos fermented with multispecies probiotic bacteria including Saccharomyces cerevisiae, Enterococcus faecium, Lactobacillus acidophilus and Bacillus subtilis. The effects of dietary CJP on the growth performance, immune status, caecal microbiology and meat oxidative stability of broiler were investigated. 2. A total of 240 one-day-old Ross broiler chicks were used in a 35-d experiment in which the chicks were randomly allotted to one of the 4 dietary treatments (0, 5, 10 and 20 g CJP/kg diet) in a completely randomised design. 3. Dietary supplementation of 5 g/kg CJP significantly increased body weight, average daily gain and average daily feed intake of broiler during the overall experimental period. 4. Serum immunoglobulin (Ig)M concentration was significantly increased by 10 and 20 g/kg CJP, whereas the IgG and IgA concentration remained unaffected. In addition, 20 g/kg CJP significantly inhibited proliferation of Escherichia coli without affecting the concentration of Lactobacillus or Bacillus spp. 5. A significant reduction in the thiobarbituric acid reactive substances values of breast and thigh meat was observed in response to increasing concentration of dietary CJP. 6. Thus, the results suggest that CJP up to a concentration of 20 g/kg can be used in the diet of broilers to improve immunity and to reduce caecal E. coli and TBARS values of breast and thigh meat without any adverse effects on growth performance.

Seamustard (Undaria pinnatifida) Improves Growth, Immunity, Fatty Acid Profile and Reduces Cholesterol in Hanwoo Steers

The study was designed to evaluate the effect of 2% seamustard (Undaria pinnatifida) by-product (SW) on growth performance, immunity, carcass characteristics, cholesterol content and fatty acid profile in Hanwoo steers. A total of 20 Hanwoo steers (ave. 22 months old; 619 kg body weight) were randomly assigned to control (basal diet) and 2% SW supplemented diet. Dietary SW supplementation significantly (p<0.05) improved average daily gain and gain:feed ratio as well as serum immunoglobulin G concentration. Chemical composition and quality grade of meat and carcass yield grades evaluated at the end of the trial were found to be unaffected by SW supplementation. Dietary SW significantly reduced meat cholesterol concentration (p<0.05). Dietary SW supplementation significantly reduced the myristic acid (C14:0) and palmitoleic acid (C16:ln-7) concentration, while SW increased the concentration of stearic acid (C18:0) and linolenic acid (C18:3n-3) compared to control (p<0.05). Dietary SW supplementation had no effect on saturated fatty acids (SFA), unsaturated fatty acids, poly unsaturated fatty acid (PUFA) or mono unsaturated fatty acid content in muscles. A reduced ratio of PUFA/SFA and n-6/n-3 were found in SW supplemented group (p<0.05). In conclusion, 2% SW supplementation was found to improve growth, immunity and fatty acid profile with significantly reduced cholesterol of beef.

Effect of Sea Tangle (Laminaria japonica) and Charcoal Supplementation as Alternatives to Antibiotics on Growth Performance and Meat Quality of Ducks

A total of 150 growing ducks were assigned to five dietary treatments to study the effect of sea tangle and charcoal (STC) supplementation on growth performance and meat characteristics in a completely randomized design. There were six replicates and five ducklings in each replication. The five dietary treatments were control, antibiotic, and 0.1%, 0.5%, and 1% STC supplemented diets. No significant differences were found on ADG, ADFI, and gain:feed among treatments in different weeks. The overall (0 to 3 weeks) ADFI decreased in antibiotic treatment (p<0.05) whereas the gain:feed increased significantly upon 1.0% STC supplementation compared to control (p<0.05). No significant variation was found in meat chemical composition except crude fat content which was high in 1.0% STC dietary group (p<0.05). Meat cholesterol was reduced in 0.1% STC group (p<0.05) compared to other dose levels while serum cholesterol was unaffected. High density lipoprotein (HDL) content was high in 1.0% STC (p<0.05) and low density lipoprotein (LDL) was low in 0.1% and 1.0% STC dietary groups (p = 0.06). No significant effect was found on the thiobarbituric acid reactive substances (TBARS) of fresh meat, whereas the TBARS value of meat preserved for 1 week was reduced significantly in STC dietary groups (p<0.05). The 0.1% STC dietary group showed an increased myristic acid (p = 0.07) content whereas, the content of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids increased in STC supplementation than antibiotic group (p<0.05). An increased concentration of omega-3 fatty acids and a reduced ratio of n-6/n-3 PUFA ratio was found upon 1.0% STC supplementation compared to antibiotic dietary group (p<0.05). Therefore, 1.0% STC dietary supplementation can be used as alternatives to antibiotics in duck production.

Evaluation of green tea by-product and green tea plus probiotics on the growth performance, meat quality and immunity of growing-finishing pigs

The present study was conducted to evaluate the effects of green tea by-product (GTB) and green tea plus probiotics (GT+P) on the growth performance, carcass characteristics, meat quality, blood parameters and immunity of growing–finishing pigs. In total, 80 crossbreed growing pigs were assigned to receive four dietary treatments for a period of 8 weeks. The dietary treatments were a basal diet (control), basal diet supplemented with 0.003% chlortetracycline (antibiotic), basal diet with 0.5% GTB (GTB) and basal diet containing 0.5% GT+P (GT+P). The results of our study indicated that bodyweight gain increased (P < 0.05) in response to the addition of GT+P to the basal diet. Crude protein and crude ash content, and shear values of loin meat were significantly (P < 0.05) increased in the GT+P group, although moisture and juiciness were decreased (P < 0.05). The GTB group had higher (P < 0.05) serum glucose concentrations, whereas the GT+P exhibited lower (P < 0.05) insulin concentrations. The values of thiobarbituric acid-reactive substances of fresh loin meat and meat that had been preserved for 1 week were lower (P < 0.05) in the GT+P group than those of the control and GTB groups. The growth of spleen cells incubated in concanavalin A (Con A) and lipopolysaccharide (LPS) medium was statistically higher (P < 0.05) for the GT+P group than for the GTB or antibiotic group. IL-6 and TNF-α production by spleen cells induced by Con A and LPS was increased in the GTB and GT+P group (P < 0.05) compared with the antibiotic group. Taken together, the results of the present study indicated that GT+P exerts positive effects on weight gain, meat composition, blood parameters and immunity in pigs, and could be used as an alternative to antibiotics for growing–finishing pig feeds.