Teck Chwen Loh

Prevalence of antibiotic resistance in lactic acid bacteria isolated from the faeces of broiler chicken in Malaysia

BackgroundProbiotics are commonly used as feed additive to substitute antibiotic as growth promoter in animal farming. Probiotic consists of lactic acid bacteria (LAB), which enhance the growth and health of the animal. Probiotic also have higher possibility to become pathogenic bacteria that may carry antibiotic resistant gene that can be transmitted to other LAB species. The aim of this study was to identify the LAB species in the faeces of broiler chicken and to determine the prevalence of antibiotic resistant in LAB of broiler chicken.MethodsSixty faeces samples were collected from wet markets located in Klang Valley of Malaysia for the isolation of LAB using de-Mann Rogosa Sharpe medium. Thirteen species of LAB were obtained in this study and the identification of LAB was performed by using API test kit on the basis of carbohydrate fermentation profile. Antibiotic susceptibility assay was then carried out to determine the prevalence of LAB antibiotic resistance.ResultsLactococcus lactis subsp lactis was found in nine out of sixty faecal samples. Lactobacillus paracasei was the second common LAB species isolated from chicken faecal. No significant difference (P > 0.05) was found between the occurrence of Lactobacillus brevis, Lactobacillus curvatus, Lactobacillus plantarum, Leuconostoc lactis mesenteroides subsp mesenteroides/dectranium and Pediococcus pentosaceus isolated from 5 different locations. Most of the isolated LAB was resistant to antibiotic and high variability of the antibiotic resistance was observed among the LAB against 15 types of antibiotics. Penicillin, amoxicillin, chloramphenicol, and ampicillin had significant higher (P< 0.05) inhibitory zone than nalidixic acid, gentamycin, sulphamethoxazole, kanamycin, and streptomycin.ConclusionsMany species of LAB were isolated from the faecal samples of broiler chicken that resistance to the common antibiotics used in the farm. The development of resistant against antibiotics in LAB can be attributed to the long term exposure of antibiotic as growth promoter and therapeutic agents. Thus, it is essential to advise farmer the safety measure of antibiotic application in animal farming. Additionally, the supplementation of probiotic in animal feeding also needs more attention and close monitoring.

Egg production, faecal pH and microbial population, small intestine morphology, and plasma and yolk cholesterol in laying hens given liquid metabolites produced by Lactobacillus plantarum strains

1. Various dosages of metabolite combinations of the Lactobacillus plantarum RI11, RG14 and RG11 strains (COM456) were used to study the egg production, faecal microflora population, faecal pH, small intestine morphology, and plasma and egg yolk cholesterol in laying hens. 2. A total of 500 Lohmann Brown hens were raised from 19 weeks to 31 weeks of age. The birds were randomly divided into 5 groups and fed on various treatment diets: (i) basal diet without supplementation of metabolites (control); (ii) basal diet supplemented with 0·3% COM456 metabolites; (iii) basal diet supplemented with 0·6% COM456 metabolites; (iv) basal diet supplemented with 0·9% COM456 metabolites; and (v) basal diet supplemented with 1·2% COM456 metabolites. 3. The inclusion of 0·6% liquid metabolite combinations, produced from three L. plantarum strains, demonstrated the best effect in improving the hens’ egg production, faecal lactic acid bacteria population, and small intestine villus height, and reducing faecal pH and Enterobacteriaceae population, and plasma and yolk cholesterol concentrations. 4. The metabolites from locally isolated L. plantarum are a possible alternative feed additive in poultry production.

Feeding of different levels of metabolite combinations produced by Lactobacillus plantarum on growth performance, fecal microflora, volatile fatty acids and villi height in broilers

The effects of feeding different dosages of metabolite combination of L. plantarum RS5, RI11, RG14 and RG11 strains (Com3456) on the performance of broiler chickens was studied. A total of 504 male Ross broilers were grouped into 7 treatments and offered different diets: (i) standard corn-soybean based diet (negative control); (ii) standard corn-soybean based diet +100 ppm neomycin and oxytetracycline (positive control); (iii) standard corn-soybean based diet + 0.1% metabolite combination of L. plantarum RS5, RI11, RG14 and RG11 strains (Com3456); (iv) standard corn-soybean based diet + 0.2% of Com3456; (v) standard corn-soybean based diet + 0.3% of Com3456 (vi) standard corn-soybean based diet + 0.4% of Com3456 and (vii) standard corn-soybean based diet + 0.5% of Com3456. Supplementation of Com3456 with different dosages improved growth performance, reduced Enterobacteriaceae and increased lactic acid bacteria count, and increased villi height of small intestine and fecal volatile fatty acid concentration. Treatment with 0.4% and 0.2% Com3456 had the best results, especially in terms of growth performance, feed conversion ratio and villi height among other dosages. However, the dosage of 0.2% was recommended due to its lower concentration yielding a similar effect as 0.4% supplementation. These results indicate that 0.2% is an optimum level to be included in the diets of broiler in order to replace antibiotic growth promoters.

Dietary methionine and n-6/n-3 polyunsaturated fatty acid ratio reduce adverse effects of infectious bursal disease in broilers

This study was carried out to investigate the modulatory effects of dietary methionine and n-6/n-3 polyunsaturated fatty acids (PUFA) ratio on immune response and performance of infectious bursal disease (IBD)-challenged broiler chickens. In total, 350 one-day-old male broiler chicks were assigned to 1 of the 6 dietary treatment groups in a 3 × 2 factorial arrangement. There were 3 n-6/n-3 PUFA ratios (45, 5.5, and 1.5) and 2 levels of methionine (NRC recommendation and twice NRC recommendation). The results showed that birds fed with dietary n-6/n-3 PUFA ratio of 5.5 had higher BW, lower feed intake, and superior FCR than other groups. However, the highest antibody response was observed in birds with dietary n-6/n-3 PUFA ratio of 1.5. Lowering n-6/n-3 PUFA ratio reduced bursa lesion score equally in birds fed with n-6/n-3 PUFA ratio of 5.5 and 1.5. Supplementation of methionine by twice the recommendation also improved FCR and reduced feed intake and bursa lesion score. However, in this study, the optimum performance (as measured by BW, feed intake, and FCR) did not coincide with the optimum immune response (as measured by antibody titer). It seems that dietary n-3 PUFA modulates the broiler chicken performance and immune response in a dose-dependent but nonlinear manner. Therefore, it can be suggested that a balance of moderate level of dietary n-6/n-3 PUFA ratio (5.5) and methionine level (twice recommendation) might enhance immune response together with performance in IBD-challenged broiler chickens.

Growth performance and fecal microflora of rats offered metabolites from lactic acid bacteria

Abstract Loh, T.C., Lee, T.M., Foo, H.L., Law, F.L. and Rajion, M.A. 2008. Growth performance and fecal microflora of rats offered metabolites from lactic acid bacteria. J. Appl. Anim. Res., 34: 61–64. The objectives of this experiment were to study the effect of metabolites produced from lactic acid bacteria (LAB) on the growth performance, Enterobacteriaceae and LAB counts in the faeces, faecal pH and plasma cholesterol. A total of 30 female postweaning rats were randomly assigned to five groups of diet: basal diet + 100% drinking water (DW), basal diet + 90% DW + 10% UL4 metabolite, basal diet + 80% DW + 20% UL4 metabolite, basal diet + 90% DW+ 10% RW18 metabolite and basal diet + 80% DW + 20% RW18 metabolite for a period of four weeks. The metabolites affected only Enterobacteriaceae counts and faecal pH, which were lower than the control groups. In conclusion, addition of lactic acid bacterial metabolites in the drinking water had only antibacterial effect in rats.

Biodegradation of palm kernel cake by cellulolytic and hemicellulolytic bacterial cultures through solid state fermentation.

Four cellulolytic and hemicellulolytic bacterial cultures were purchased from the Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Culture (DSMZ) and the American Type Culture Collection (ATCC). Two experiments were conducted; the objective of the first experiment was to determine the optimum time period required for solid state fermentation (SSF) of palm kernel cake (PKC), whereas the objective of the second experiment was to investigate the effect of combinations of these cellulolytic and hemicellulolytic bacteria on the nutritive quality of the PKC. In the first experiment, the SSF was lasted for 12 days with inoculum size of 10% (v/w) on different PKC to moisture ratios. In the second experiment, fifteen combinations were created among the four microbes with one untreated PKC as a control. The SSF lasted for 9 days, and the samples were autoclaved, dried, and analyzed for proximate analysis. Results showed that bacterial cultures produced high enzymes activities at the 4th day of SSF, whereas their abilities to produce enzymes tended to be decreased to reach zero at the 8th day of SSF. Findings in the second experiment showed that hemicellulose and cellulose was significantly (P < 0.05) decreased, whereas the amount of reducing sugars were significantly (P < 0.05) increased in the fermented PKC (FPKC) compared with untreated PKC.

Utilisation of Earthworm Meal in Partial Replacement of Soybean and Fish Meals in Diets of Broilers

Abstract Loh, T.C, Fong, L.Y., Foo, H.L., Thanh, N.T. and Sheikh-Omar, A.R. 2009. Utilisation of earthworm meal in partial replacement of soybean and fish meals in diets of broilers. J. Appl. Anim. Res., 36: 29–32. To study the effect of worm meal (WM) as partial replacement of soybean and fish meals in the diets, a total of 245 day-old broiler chicks were randomly assigned to five different treatment groups (0%, 5%, 10%, 15% and 20% WM) in partial replacement of soybean and fish meals for a period of 6 weeks. The final body weight, growth rate and feed efficiency of the 10% and 15% WM groups broiler were better (P<0.05) than that of the control group with no effect on feed intake. The digestibility of crude protein for WM was 63%. 10% WM group gave a higher (P<0.05) lactic acid bacteria counts and showed no significant difference (P>0.05) in Enterobacteriaceae count or fecal pH. These results suggest that WM could be used to replace soybean and fish meals between 10 to 15% in broiler diets.

Effects of different levels of metabolite combination produced by Lactobacillus plantarum on growth performance, diarrhoea, gut environment and digestibility of postweaning piglets

A study was conducted to investigate the effects of different levels of metabolite combinations produced by Lactobacillus plantarum on growth performance, diarrhoea incidence, gut environment and nutrient digestibility in postweaning piglets. A total of 40 piglets were assigned into one of five treatments: (1) negative control (free antibiotic); (2) positive control (0.03% antibiotic of chlortetracycline); (3) Met 1 (0.1% metabolite combination of TL1, RG14 and RS5 strains); (4) Met 3 (0.3% metabolite combination of TL1, RG14 and RS5 strains); and (5) Met 5 (0.5% metabolite combination of TL1, RG14 and RS5 strains). After 5 weeks of the trial, the average daily gain (ADG) and daily feed intake (DFI) was significantly (P < 0.05) improved in Met 5 group compared to the negative control and Met 1 group. The diarrhoea incidence was significantly (P<0.05) reduced when were piglets fed with positive control and Met 5 dietary treatment. The pH value and Enterobacteriaceae (ENT) in the gut were reduced in Met 5 treatment as compared to negative control and Met 1 group. However, lactic acid bacteria (LAB) counts and short chain fatty acids (SCFA) in the gut were significantly higher (P<0.05) when piglets were fed with Met 5 dietary treatment. In contrast, feeding of metabolite combination to piglets did not improve energy utilisation. In addition, piglets fed with Met 5 dietary treatment improved protein digestibility compared to the negative control and Met 1 group. The results obtained in this study showed that feeding of 0.5% metabolite combinations could improve growth performance, gut health environment and protein digestibility in postweaning piglets.

Physico-chemical properties of breast muscle in broiler chickens fed probiotics, antibiotics or antibiotic–probiotic mix

ABSTRACT This study investigated the efficacy of antibiotics, probiotics and their combination on meat quality of breast muscle in broilers. A total of 480 male one-day-old Cobb chicks were randomly assigned to control (without additive), antibiotic growth promoter (AGP), Bioplus® (probiotics), or AGP + Bioplus® and raised for 42 d. Each treatment was replicated six times with 20 birds per replicate. At the end of rearing period, 10 birds were randomly selected from each treatment, slaughtered and the breast muscles were excised for meat quality analyses. The results showed that all additives influenced drip and cooking loses, pH, fat content and colour attributes of breast muscle but did not affect tenderness, muscle glycogen, moisture, crude protein and ash content of breast muscle. Both drip and cooking losses were lower in treatment groups than those in the control group. Birds fed sole probiotics had the least pH, drip loss and cooking loss compared with the other treatments. Sole probiotics-fed birds had higher lightness, redness and yellowness values and lower fat value than the other treatments on day 1 post-mortem. The results indicate that probiotics are good substitutes for antibiotics in the diet of broiler chickens for the enhancement of meat quality.

Effects of dietary oil sources, calcium and phosphorus levels on growth performance, carcass characteristics and bone quality of broiler chickens

ABSTRACT The study investigated the effects of varying dietary calcium (Ca) level and oil sources on the growth performance and carcass quality of broiler chickens. A total of 378, 1-day-old birds (Cobb 500) were fed either 6% palm oil, soybean oil (SO) or linseed oil (LO) in combination with three dietary levels of calcium (1.00%, 1.25% and 1.50%) for 6 weeks. Birds fed SO had higher body weight (BW) compared with those fed LO (p < .05). However, feed efficiency, carcass and bone quality were similar among the oil treatments. Regardless of the oil source, chicken fed diets containing 1.50% of Ca had lower BW compared with those fed 1.00% and 1.25% of Ca. In contrast, birds fed 1.25% of Ca had significantly higher (p < .05) bone quality than those fed 1% of Ca. It can be concluded that increasing the level of calcium up to 1.25% improved bone quality regardless of the type of oil.