ROLE OF PROBIOTICS IN IMPROVING MICROBIAL LOAD OF BROILER CHICKEN CARCASSES

Document Type : Research article

Authors

Animal Health Research Institute, Mansoura branch

Abstract

A total number of 90 one day old chicks were purchased from a poultry company at Mansoura city and divided into three groups (each of 30). All groups were prophylactically vaccinated according to the local routine vaccination programme. The first group (control group) was fed a basal diet (without probiotics), whereas 2nd&3rd groups were fed on the same basal diet supplemented with probiotics. At 42nddays of age, broilers were slaughtered, processed and bacteriologically examined foraerobic plate count (APC),enumeration of Coliforms (MPN), E. coli count, detection of Salmonellae, Campylobacter jejuni and  E. coli where the log mean of APC in group 1, group2 and group3 were 5.5±0.9, 4.9±1 and 4.8±0.8 log10cfu/ gm, the MPN of Coliforms were 3.4±0.9,3±0.9 and 2.7± 0.8 log10cfu/ gm, E. coli count  were 3.3±1, 3±0.8 and 2.9±0.7 log10 cfu/ gm with reduction percent from 40% to 30% and 33.3%, meanwhile The incidence of Salmonellae were reduced from 30% to 16.6% and 10% and Campylobacter jejuni incidence were reduced from 20% to 6.6% and 3.3% respectively. The experiment was triplicated and the results in group2 and group3 were reduced significantly (P<0.05).   

Keywords


ROLE OF PROBIOTICS IN IMPROVING MICROBIAL LOAD OF BROILER CHICKEN CARCASSES

                 

EL-DOSOKY, H.F.A.; SANYA, T. EL-GHAMRY and AZZA, E.A. HASSAN

Animal Health Research Institute, Mansoura branch

Email: nogoom.1980@gmail.com

 

 

 

ABSTRACT

 

 

Received at: 9/12/2013

 

 

Accepted: 4/2/2014

 

A total number of 90 one day old chicks were purchased from a poultry company at Mansoura city and divided into three groups (each of 30). All groups were prophylactically vaccinated according to the local routine vaccination programme. The first group (control group) was fed a basal diet (without probiotics), whereas 2nd&3rd groups were fed on the same basal diet supplemented with probiotics. At 42nddays of age, broilers were slaughtered, processed and bacteriologically examined foraerobic plate count (APC),enumeration of Coliforms (MPN), E. coli count, detection of Salmonellae, Campylobacter jejuni and  E. coli where the log mean of APC in group 1, group2 and group3 were 5.5±0.9, 4.9±1 and 4.8±0.8 log10cfu/ gm, the MPN of Coliforms were 3.4±0.9,3±0.9 and 2.7± 0.8 log10cfu/ gm, E. coli count  were 3.3±1, 3±0.8 and 2.9±0.7 log10 cfu/ gm with reduction percent from 40% to 30% and 33.3%, meanwhile The incidence of Salmonellae were reduced from 30% to 16.6% and 10% and Campylobacter jejuni incidence were reduced from 20% to 6.6% and 3.3% respectively. The experiment was triplicated and the results in group2 and group3 were reduced significantly (P<0.05).   

 

 

Key words: Probiotics, Microbial load, Broiler chicken

 

                


INTRODUCTION

 

Probiotics are defined as viable microorganisms (bacteria or yeast) that exhibit a beneficial effect on the health of their host when they were ingested (Salminen et al., 1998). The use of probiotics have started after the study reported by(Nurmi and Rantala, 1973) where the original objective was to control Salmonella infection and occupied the adhesion sites on intestinal epithelium, hence addition of probiotics have the objective of preventing the intestinal colonization of enteropathogenic bacteria in birds since probiotics and pathogenic bacteria compete for nutrients(Silva, 2000). Using of probiotics have been extensively studied world wide as a possible alternative for antibiotics byJernigan and Kornegay (1985); Stavric and Kornegay (1995); Newmanand Jacques (1995); England et al. (1996) and Pelicano et al. (2002). Jin et al. (1996) found that inclusion of probiotics (Lactobacilli and Bacillus subtilis)in the diet stimulated the favorable microbial balance in the gut leading to improving food efficiency and growth performance in broilers, therefore there is a world trend to reduce the usage of antibiotics in animal feed due to residues problems in the final product, most of broiler industry practitioners have been given a growth promoter as an additive in the ration Menten (2001 and 2002).

 

Therefore, the aim of this work was to evaluate the effect of probiotics as feed supplement on the bacteriological status of broiler chicken carcasses.

 

MATERIALS and METHODS

 

A total number of 90 one-day-old Cobb chicks were purchased from a poultry company at Mansoura city and divided into three groups. All groups were prophylactically vaccinated according to the local routine vaccination programme. Chicks were reared in three separated pens (3x2m) under good hygienic conditions.

 

The first group (control group) was fed on a basal diet (without growth promoters) which mixed first, placed in a clean unused sacks.

 

The second group was fed on the same basal dietsupplemented with Bacillus subtilis spores 4x105CFU/gm at 1.5 kgm/ton (Megalo, Amoun Man. Add. EL-obour city, Cairo, Egypt) added to the diet all over the period according to the manufacturer,s instructions and thoroughly mixed, placed in a clean unused sacks.

 

The third group was fed on the same basal dietcontained similar proportion of six strains of variable organisms namely Lactobacillus acidophilus and Lactobacillus casei, Bifidobacterium bifidum, Aspergillus oryzae, Streptococcus faecium and Torulopsis sps added to the diet at 100 mg/kg diet all over the period of the experiment and thoroughly mixed, placed in a clean unused sacks and stored at room temperature.

 

The chicken fed on the aforementioned diets from 1stto 42nd day of age. The chicken was allowed to have free access to a starter diet with crude protein (21.5%) during the first three weeks and then to a finisher diet with crude protein (19.5%) during the second three weeks and free access of water. The experiment was repeated three times. There was a complete separation between different groups, the house was locked at all times to prevent unauthorized entry. Prior to initiating this study the house was thoroughly cleaned, sanitized, disinfected and new wood shavings litter were placed. At 42nd of age, broilers were slaughtered and processed then placed on ice till bacterial examination. All equipments were cleaned, sanitized using commercial sanitizer after each time.

 

Bacteriological Examination:

muscle and skin tissues (25gm) from each chicken were homogenized with 225ml of 0.1% peptone water in a stomacher for 2.5 minutes at 3000 rpm followed by ten fold six serial dilution in 0.1% peptone water. Each of the prepared samples were examined for enumeration of its bacterial content as follows:

 

1- Aerobic plate countaccording to APHA (2001)

 

2- Enumeration of Coliformsaccording to FDA (2005)

 

3- Escherchia coli counts according to FDA (2005)   

 

4- Isolation and identification of Salmonellae and Campylobacter jejuniwere done according to the techniques recommended byFDA (2005) andSmibert (1984)respectively.


 


 

RESULTS

 

Table1: Illustrates statistical analytical results of Aerobic plate count, Coliforms (MPN) and E. coli of the examined broiler carcasses fed on probiotics expressed as log cfu/gm (n=30).  

                                                     

Group3

(treated feed)

Group2

(treated feed)

Group1

(control group)

Microbial count

Logcfu/gm ±S.E.

4.8±0.8 *

4.9±1*

5.5±0.9

Aerobic plate count

2.7±0.8 *

3±0.9 *

3.4±0.9

MPN of Coliforms

2.9±0.7 *

3±0.8*

3.3±1

E. coli count

 

  N.B. APC=aerobic plate count, MPN=most probable number of Coliforms, *Means the results were significantly different (P<0.05).

 

Table 2: Shows the incidence of the tested bacteria in the examined +ve samples.

 

Group3

(treated feed)

Group2

(treated  feed)

Group1

control group

Microbial incidence

 

%

No

%

No

%

No

33.3

10

30

9

40

12

E. coli

10

3

16.6

5

30

9

Salmonellae

3.3

1

6.6

2

20

6

Campylobacter jejuni

 


DISCUSSION

 

Probiotics were used to get rid of abnormalities in the gastrointestinal tract produced by stress and therefore normalize the gut activity (Kutlu and Gorgulu, 2001), hence the achieved results gave a profile about the effect of some probiotics on microbial content of broiler carcasses. The results inTable (1) showed that the mean of APC in group 1 (control group), group 2 and group 3 were 5.5±0.9, 4.9±1 and 4.8±0.8 log10cfu/ gm respectively, the results were reduced significantly (P<0.05) and in accordance with Fritts et al. (2000)who achieved reduction in APC, from 4.34 to 4.17 log10cfu/gm in the examined broiler chicken carcasses, Ali (2010) APC reduced from 6.35±0.72 to 4.81±0.25 log10 cfu/gm, after addition of bacillus subtilis spores to the chicken diet and Khaksefidi and Rahimi (2005)after using a basal diet contain Lactobacillus acidophilus and Lactobacillus casei, Bifidobacterium bifidum, Aspergillus oryzae, Streptococcus faecium and Torulopsis sps. The results were reduced significantly (P<0.05) in chicken fed on diet supplemented with probiotics as compared with control group.

 

Table (1) declared that the meanMPNof Coliforms were 3.4±0.9,3±0.9 and 2.7±0.8 log10cfu/gm respectively, where the results were reduced significantly (P<0.05) in agree with Fritts et al. (2000) who achieved Coliforms reduction from 2.37 to 2.12 log10cfu/ml in the examined broiler chicken carcasses, Khaksefidi and Rahimi (2005) from 2.52 to1.55 log cfu /ml and so Ali (2010) from 3.50±0.20 to 2.40±0.20 log10cfu /gm.

 

The obtained results of E. coli count inTables (1&2) were significantly reduced (P<0.05) where the counts were 3.3±1, 3±0.8 and 2.9±0.7 log10 cfu/gm with reduction percent from 40% to 30% and 33.3%respectively as those obtained byFritts et al. (2000)who reported that E. coli reduced from 2.58 to 2.27 log10cfu/gm after probiotics addition to the diet, also Ali (2010) mentioned that E. coli incidence reduced from 40% to 33.3%.

 

The incidence results in table (2) declared that using of probiotics reduce Salmonellae from 30% to 16.6% and 10% respectively these results were similarly to those recorded byCaramori, (2001) who used probiotics in flocks challenged with Salmonella enteritidis, Fritts et al. (2000) obtained 40% reduction in Salmonella spp., Maruta et al. (1996), Khaksefidi and Rahimi (2005) andCaramori et al. (2005) reported 60% reduction of experimentally infected broilers with Salmonella enteritidis and Ali (2010) recorded that probiotics feeding reduce Salmonellae incidence from 33.3% to 20%.

 

The incidence resultsof Campylobacter jejuni (C. jejuni) in table (2) after probiotics feeding in chicken carcasses were reduced from 20% to 6.6% and 3.3% respectivelysimilarly to Fritts et al. (2000) who reported reduction from 3.43 to 2.85 log10cfu/ml, while Maruta et al. (1996) andKhaksefidi and Rahimi (2005)found reduction from 3.04 to 2.67 log cfu /ml respectively and Ali (2010) obtained reduction from 16.6% to non detected.

 

The bacteriocidal effect of probiotics were probably accompanied with production of antibodies this confirmed the hypothesis of Chaveerach et al. (2004)and the reduction of microbial load may be due to production of different antimicrobial components by probiotics such as organic acids, hydrogen peroxides, carbon peroxides, diacetyl, low molecular weight antimicrobial substances, bacteriocins and adhesion inhibitors. Some bacteriocins produced by specific probiotics strains can fulfill a role in the inhibition of common broiler pathogens, this agree with Andreatti and Sampalo, (1999), Avonts and De Vuyst (2001) and Meurman (2005) and stimulate intestinal immunity (Ouwerhand et al., 1999)in addition to the results reported byChiang and Hsieh (1995)andTakahashi et al. (2005) aboutbroilers fed probiotic-supplemented diet showed better carcass yield and meat quality when compared to the broilers fed the unsupplemented diet.

 

In conclusion, probiotics addition to chicken diet as a feed supplement were recommended to improve the growth, microbial status and carcass yield of broiler chicken carcasses.

 

REFERENCES

 

Ali, H.M. Fatma (2010): Probiotic Feed supplement to Improve Quality of broiler chicken carcasses. World Journal of Dairy and Food Sciences. 5(1); 93-99.                                                               

 Andreatti, F.R. and Sampalo, H.M. (1999): Probioticos e prebioticos Realiade na avicultura industrial moderna. Revista de Educacao Continuadado CRMV-SP.2,3; 59-71.                    

APHA (American Public Health Association) (2001): Compendium of methods for the microbiological examination of food, Washington, DC.                                                                

Avonts, L. and De Vuyst, L. (2001): Antimicrobial potential of probiotic lactic acid bacteria. Meded Rijksuniv Gent Fak Landbouwkd Toegep Biol. Wet., 66 (3b); 543-550.

Caramori, J.J.; Roca, R.; de O.; Pinto, J.P. de, A.N.; Andreati Filho, R.L.; Mendes, A.A.; Padovani, C.R.; Moscari  Junior, E.M. and Raghianti, F. (2005): Evaluation of the presence of Salmonella spp. in carcasses of broilers fed with probiotics prebiotics. Hygiene Alimentar, 19,133; 72-78.     

Caramori, J.J. (2001): Efeito de probioticos e prebioticos na racao de frangos e corte sobre o desempenho, rendimento e carcaca, caracteristicas quimicas e presenca de Salmonella spp.na carne (tese) Botucatu (SP); Universidade Estadual Paulista.        

Chaveerach, P.; Lipman, L.J. and Vanknapen, F. (2004): Antagonisti c activities of several bacteria on in vitro growth of 10 strains of Campylobacter jejuni/coli. Int. J. Food Microbiol., 90 (1); 43-50.

Chiang, S.H. and Hsieh, W.M. (1995): Effect of direct-fed microorganisms on broiler growth performance and litter ammonia level. Asian-Aust. J. Anim. Sci. 8,2; 159-162. 

England, J.A.; Walkins, S.E.; Saleh, E.; Waldroup, P.W.; Casas, I. and Burnham, D. (1996): Effect of lactobacillus reuleri on live performance and intestinal development of male turkeys. J. Appl. Poultry Res.5; 311-324.                  

Food and Drug Administration (FDA) (2005): Staphylococcus aureus, Bad Bug Book, Foodborne Pathogenic Microorganisms and Natural Toxins Handbook (1992/updated 2005), USFDA/FDA, Center for food safety and Applied Nutrition.             

Fritts, C.A.; Kersey, J.H.; Motl, M.A.; Kroger, E.C.; Yan, F.; Si, J.; Jiang, Q.; Campos, M.M.; Waldroup, A.L. and Waldroup, P.W. (2000): Bacillus subtilis C-3102 (Calsporin) improves live performance and microbiological status of broiler chickens. J. Appl. Poultry Res. 9;     149-155.                

Jernigan, M.A. and Kornegay, E.T. (1985): Probiotics in poultry nutrition-A review. World,s Poultry Sci. Assn. J.,41; 99-107.

Jin, L.Z.; Ho, Y.W.; Abdullah, N. and Jalaludin (1996): Influence of dried Bacillus subtilis and lactobacilli culture on intestinal microflora and performance in broilersAsian-Aust. J. Anim. Sci. 9; 397-404.

Khaksefidi, A. and Rahimi, Sh. (2005): Effect of probiotic inclusion in the diet of broiler chickens on performance, feed efficiency and carcass quality. Asian-Aust. J. Anim. Sci. 18,8; 1153-1156.

Kutlu, H.R. and Gorgulu, M. (2001): Feed additive alternative to antibiotic-growing factors, used in poultry diets. Yem Magazin Dergisi, 27;   45-51.

Maruta, K.; Miyazaki, H.; Masuda, S.; Takahashi, M.; Marubashi, T.; Tadano, Y. and Takahashi, H. (1996): Exclusion of intestinal pathogens by continuous feeding with Bacillus subtilis C-3102 and its influence on the intestinal microflora in broilers. Animal Sci. Tech. (Japan) 67,3; 273-280.   

Menten, J.F.M. (2001): Additives alternatives na nutricao de aves: probiotics sociedade Brasileiros, piracicaba. Fealq. pp.141-157.                                                                                   

Menten, J.F.M. (2002): Probiotics, Prebiotics e aditivos Fitogenicos na nutricao de aves. 11 Simposio, sobre Ingredientes na Alimentacao Animal CBNA, pp. 251-275.

Meurman, J.H. (2005): Probiotics;do they have a role in oral medicine and dentistry. Eur. J. Oral Sci., 113 (3); 188-196.

Newman, K.E. and Jacques, K.A. (1995): Microbial feed additives for preruminants. Pages 247-258. In Biotechnology in animal feeds and animal feeding. Wallace, R.J. and Chesson, A. eds. V.C.H. Press, Weinheim, Germany.

Nurmi, E. and Rantala, M. (1973): New aspects of Salmonella infection in broilerproduction. Nature, 241; 210-211.                                     

Owerhand, A.C.; Kirjavainen, P.V. and Short, C. (1999): Probiotics mechanisms and established effects. International Dairy Journal.9; 43-52.      

Pelicano, E.R.L.; Souza, P.A. and Souza, H.B.A. (2002): Probioticos e prebioticos nanutricao de aves. Ciencias Agrarias e da Saude. 2,1;  59-64.                                                         

Salminen, S.A. von Wright; Morelli, L.; Martean, P.; Brassart, D.; De Vos, W.M.; Fonden, R.; Saxelin, M.; Collins, K.; Mogensen, G.; Birkeland, S.E. and Matilla-Sandholm, T. (1998): Demonstration of safety of probiotics-A review. Int. J. Food Microbiology, 44;      93-106.   

Silva, E.N. (2000): Probioticos e prebioticos na alimentacao de aves. In; Conferencia APINCO de Ciencia e Tecnologia  Avicolas; Sao Paulo. Trabalhos de pesquisas. Campinas; FACTA; 241-251. 

Smibert, R.M.(1984): Genus Campylobacter, sebald and Veron 1963,907 in Bergey,s Manual of Systemic Bacteriology Ed. by Krieg, N.R. and Holt, J.G. 9th Ed. Williams and Wilkins, Baltimore pp111-117.

Stavric, S. and Kornegay, E.T. (1995): Microbial probiotics for pigs and poultry. Pages 205-231 in Biotechnology in animal feeds and animal feeding. Wallace, R.J. and Chesson, A. eds. V.C.H. Press, Weinheim, Germany.   

Takahashi, S.E; Mendes, A.A.; Saldanha, E.S.P.B.; Pizzolante, C.C.; Pelicia, K.; Quinteiro, R.R.; Komlyama, C.M.; Garcia, R.G. and Almeida Paz, I.C.L. (2005): Efficiency of probiotics and prebiotics on the performance, yield, meat quality and presence of Salmonella spp. in carcasses of free range broiler chickens. Revista Brasileira de Ciencia Avicola.7,3;   151-157.

 

 

 

 

 

 

دور البروبيوتک في تحسين الحمل البکتيري لذبائح بداري التسمين

 

حاتم فتحي احمد الدسوقي , سنية طه الغمري ، عزة السيد علي حسان

Email: nogoom.1980@gmail.com

 

 

اشتملت الدراسة على عدد تسعين کتکوت عمر يوم تم تجميعها من احدى شرکات الدواجن بمدينة المنصورة حيث تم تقسيمها إلى ثلاث مجموعات (ثلاثون کتکوت لکل مجموعة) وتربيتها وتغذيتها منفصلة علي عليقة أساسية للمجموعة الأولي أما المجموعة الثانية والثالثة تم تغذيتها علي العليقة الأساسية مضافا عليها البروبيوتک وبعد مرور42 يوم تم ذبح کل مجموعة منفصلة داخل المجزر وبعد انتهاء مراحل الإعداد والتجهيز قبل التغليف مباشرة تم اخذ العينات للفحص البکتيري لمعرفة العد الکلي للميکروبات الهوائية والعد الکلي لميکروب الايشريشيا کولاي والعد الاحتمالي للميکروبات القولونية ومعرفة مدي تواجد ميکروبات السالمونيلا والکامبيلوباکتر جيجيوناي حيث أظهرت النتائج بعد تکرار التجربة ثلاث مرات وجود تأثير واضح للبروبيوتک علي الإقلال من تواجد البکتيريا السابقة , حيث إن متوسط العد الکلي للميکروبات الهوائية کان 5,5±0,9, 4,9 ±1 و 4,8±0,8 / جم, متوسط العد الکلي لميکروب الايشريشيا کولاي کان 3,3 ±1, 3±0,8 و2,9±0,7 / جم والعد الاحتمالي للميکروبات القولونية کان 3,4±0,9, 3±0,9, و2,7±0,8 /جم علي الترتيب للمجموعات الثلاث بينما تم عزل ميکروب السالمونيلا والکامبيلوباکتر جيجيوناي من العينات السابقة بنسبة اقل من المجموعة الأولي مما سبق يتضح أن إضافة البروبيوتک له تأثير واضح علي الإقلال من تواجد البکتيريا وتحسين صفات لحوم الدواجن. 

REFERENCES
 
Ali, H.M. Fatma (2010): Probiotic Feed supplement to Improve Quality of broiler chicken carcasses. World Journal of Dairy and Food Sciences. 5(1); 93-99.                                                               
 Andreatti, F.R. and Sampalo, H.M. (1999): Probioticos e prebioticos Realiade na avicultura industrial moderna. Revista de Educacao Continuadado CRMV-SP.2,3; 59-71.                    
APHA (American Public Health Association) (2001): Compendium of methods for the microbiological examination of food, Washington, DC.                                                                
Avonts, L. and De Vuyst, L. (2001): Antimicrobial potential of probiotic lactic acid bacteria. Meded Rijksuniv Gent Fak Landbouwkd Toegep Biol. Wet., 66 (3b); 543-550.
Caramori, J.J.; Roca, R.; de O.; Pinto, J.P. de, A.N.; Andreati Filho, R.L.; Mendes, A.A.; Padovani, C.R.; Moscari  Junior, E.M. and Raghianti, F. (2005): Evaluation of the presence of Salmonella spp. in carcasses of broilers fed with probiotics prebiotics. Hygiene Alimentar, 19,133; 72-78.     
Caramori, J.J. (2001): Efeito de probioticos e prebioticos na racao de frangos e corte sobre o desempenho, rendimento e carcaca, caracteristicas quimicas e presenca de Salmonella spp.na carne (tese) Botucatu (SP); Universidade Estadual Paulista.        
Chaveerach, P.; Lipman, L.J. and Vanknapen, F. (2004): Antagonisti c activities of several bacteria on in vitro growth of 10 strains of Campylobacter jejuni/coli. Int. J. Food Microbiol., 90 (1); 43-50.
Chiang, S.H. and Hsieh, W.M. (1995): Effect of direct-fed microorganisms on broiler growth performance and litter ammonia level. Asian-Aust. J. Anim. Sci. 8,2; 159-162. 
England, J.A.; Walkins, S.E.; Saleh, E.; Waldroup, P.W.; Casas, I. and Burnham, D. (1996): Effect of lactobacillus reuleri on live performance and intestinal development of male turkeys. J. Appl. Poultry Res.5; 311-324.                  
Food and Drug Administration (FDA) (2005): Staphylococcus aureus, Bad Bug Book, Foodborne Pathogenic Microorganisms and Natural Toxins Handbook (1992/updated 2005), USFDA/FDA, Center for food safety and Applied Nutrition.             
Fritts, C.A.; Kersey, J.H.; Motl, M.A.; Kroger, E.C.; Yan, F.; Si, J.; Jiang, Q.; Campos, M.M.; Waldroup, A.L. and Waldroup, P.W. (2000): Bacillus subtilis C-3102 (Calsporin) improves live performance and microbiological status of broiler chickens. J. Appl. Poultry Res. 9;     149-155.                
Jernigan, M.A. and Kornegay, E.T. (1985): Probiotics in poultry nutrition-A review. World,s Poultry Sci. Assn. J.,41; 99-107.
Jin, L.Z.; Ho, Y.W.; Abdullah, N. and Jalaludin (1996): Influence of dried Bacillus subtilis and lactobacilli culture on intestinal microflora and performance in broilersAsian-Aust. J. Anim. Sci. 9; 397-404.
Khaksefidi, A. and Rahimi, Sh. (2005): Effect of probiotic inclusion in the diet of broiler chickens on performance, feed efficiency and carcass quality. Asian-Aust. J. Anim. Sci. 18,8; 1153-1156.
Kutlu, H.R. and Gorgulu, M. (2001): Feed additive alternative to antibiotic-growing factors, used in poultry diets. Yem Magazin Dergisi, 27;   45-51.
Maruta, K.; Miyazaki, H.; Masuda, S.; Takahashi, M.; Marubashi, T.; Tadano, Y. and Takahashi, H. (1996): Exclusion of intestinal pathogens by continuous feeding with Bacillus subtilis C-3102 and its influence on the intestinal microflora in broilers. Animal Sci. Tech. (Japan) 67,3; 273-280.   
Menten, J.F.M. (2001): Additives alternatives na nutricao de aves: probiotics sociedade Brasileiros, piracicaba. Fealq. pp.141-157.                                                                                   
Menten, J.F.M. (2002): Probiotics, Prebiotics e aditivos Fitogenicos na nutricao de aves. 11 Simposio, sobre Ingredientes na Alimentacao Animal CBNA, pp. 251-275.
Meurman, J.H. (2005): Probiotics;do they have a role in oral medicine and dentistry. Eur. J. Oral Sci., 113 (3); 188-196.
Newman, K.E. and Jacques, K.A. (1995): Microbial feed additives for preruminants. Pages 247-258. In Biotechnology in animal feeds and animal feeding. Wallace, R.J. and Chesson, A. eds. V.C.H. Press, Weinheim, Germany.
Nurmi, E. and Rantala, M. (1973): New aspects of Salmonella infection in broilerproduction. Nature, 241; 210-211.                                     
Owerhand, A.C.; Kirjavainen, P.V. and Short, C. (1999): Probiotics mechanisms and established effects. International Dairy Journal.9; 43-52.      
Pelicano, E.R.L.; Souza, P.A. and Souza, H.B.A. (2002): Probioticos e prebioticos nanutricao de aves. Ciencias Agrarias e da Saude. 2,1;  59-64.                                                         
Salminen, S.A. von Wright; Morelli, L.; Martean, P.; Brassart, D.; De Vos, W.M.; Fonden, R.; Saxelin, M.; Collins, K.; Mogensen, G.; Birkeland, S.E. and Matilla-Sandholm, T. (1998): Demonstration of safety of probiotics-A review. Int. J. Food Microbiology, 44;      93-106.   
Silva, E.N. (2000): Probioticos e prebioticos na alimentacao de aves. In; Conferencia APINCO de Ciencia e Tecnologia  Avicolas; Sao Paulo. Trabalhos de pesquisas. Campinas; FACTA; 241-251. 
Smibert, R.M.(1984): Genus Campylobacter, sebald and Veron 1963,907 in Bergey,s Manual of Systemic Bacteriology Ed. by Krieg, N.R. and Holt, J.G. 9th Ed. Williams and Wilkins, Baltimore pp111-117.
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