INTRODUCTION:

The rumen harbours various types of bacteria which are active in degradation of the components of the feed. The interaction among themselves and with other microbial groups in the rumen also responsible for synergistic effect on the production of volatile fatty acids and microbial proteins in the Rumen. The bacteria isolated from the Rumen of Indian cattle and Buffalo were represented by Ruminococci to the extent of 50-94% on feeding of 15% sugarcane molasses and 2-3% Urea to the animals (Panjarathinum et al., 1977). Some of the cellulose degrading bacteria isolated from the Rumen of Buffalo include Fibrobacter succinogens, Ruminococus albus, and Ruminococus flavefaciens (Jalaludin et.al., 1999). Feeding of Berseem supported increased number of cellulose degrading bacteria and were represented by Ruminococus albus and Ruminococus flavefaciens (59.8%) Bacteroides succinogens (19.2%) Butrivibrio fibrosolvens (11.1%), Clostridium lochheadii (3.8%), Clostridium longisporum (1.3%)(Sinha et al., 1983).

Bacteriocins are antimicrobial peptides produced by bacteria having biologically active moiety with bactericidal activity has ability to inhibit the closely related and unrelated bacterial isolates, rumen is a rich source of anaerobic microbes which are essential for digestion and these bacteriocins as an effective tool in manuplating the rumen fermentation in order to improve the feed efficiency and decrease the methane and acetate production. since limited usage of chemical ionopore antibiotics due to toxicity and residues in meat and milk , bacteriocins are naturally synthesized and can be easily purified it could be a potential alternative to ionopore antibiotics (Ravikumar et al 2013).

RUMINAL LACTIC ACIDOSIS:

Ruminal lactic acidosis refers to a series of conditions that resulted in decrease in pH rumen of cattle, sheep and goat, resulted from ingestion of large amount of feed rich in highly fermentable carbohydrates .Acidosis is a pathological condition associated with the accumulation of acid or depletion of alkaline reserves in blood and body tissues, and characterized by increased hydrogen ion concentrations (Bloodand Studdert 1988). Rumen lactic acidosis (grain overload, grain poisoning, acute indigestion) develops in sheep and cattle that have ingested large amounts of unaccustomed feeds rich in ruminally fermentable carbohydrates (Crichlow and Chaplin 1985; Nocek 1997).The resulting production of large quantities of volatile fatty acids (VFA) and lactic acid decreases rumen pH to non-physiological levels, simultaneously weakening the buffering capacity of the rumen, and reduces the efficiency of rumen flora and fermentation. The condition is clinically characterised by intoxication, the symptoms of which are loss of appetite, rumen atony, diarrhoea, grinding (pain) and paresis. The consequences of failure to treat, or the late treatment of the disease, is coma or death (Dirksen, 1986). Among clinical findings are lactic acidosis, haemoconcentration, dehydration, varying degrees of rumenitis and hyperosmolality. As a consequence of the reduction in blood bicarbonate content, the buffer capacity of the blood is severely reduced. In Lactic acidosis can cause ruminitis, metabolic acidosis, lameness, hepatic abscessation, pneumonia and death (Lean, Wade et al. 2001).

INTRARUMINAL CHANGES DURING LACTIC ACIDOSIS:

Initially, this metabolic insult increases the growth rates of all bacteria in the rumen, resulting in an increase in total volatile fatty acid production and a decrease in ruminal pH. It is likely that the provision of increased substrates for microbial production, e.g. ammonia and peptides, will favour bacterial growth rather than production of VFA. When large amounts of starch are added to the diet, the growth of Streptococcus bovis is no longer restricted by a lack of this energy source and this population grows faster than other species of rumen bacteria (Russell and Hino 1985). S. bovis produces lactic acid, an acid 10 times stronger than acetic, propionic or butyric acid, the accumulation of which eventually exceeds the buffering capacity of rumen fluid. Glucose produced from the breakdown of starch and other carbohydrates are converted to fructose 1,6-diphosphate, Russell and Hino (1985) found that fructose 1,6-diphosphate had a positive feedback on the conversion of pyruvate to lactate by activating lactate dehydrogenase. Fructose,6-diphosphate is also converted to triose phosphate in increasing concentrations. Triose phosphate acts to inhibit pyruvate formate lyase. The net effect of these changes is a switch from predominantly acetate and formate production to lactate production (Russell and Hino 1985).

CURRENT SCENARIO IN PREVENTING LACTIC ACIDOSIS:

Recent study performed by Nocek et al (2002), has shown effective increase in pH after direct inoculation of microorganisms into rumen. Three types of microorganisms (Enterococcus faeccium, Lactobacillus plantarum and Sacchoromyces cerevisae) were applied intraruminaly. These microorganisms are lactate utilising and it is believed that they effectively prevent accumulation of lactic acid and lead to higher pH. Direct inoculation of Selenomonas ruminantium and Megasphaera elsdenii is brought to question, since survival of these microorganisms is very short (Owens et al 1996, Dirksen 1985).Buffers are good matters in prevention and therapy of all forms of acidosis (Rossow 1984, Garry 2002). In cases where cows are fed meals with high concentrated feed content, preventive use buffers can lower possibilities of rumen pH decrease (GARRY 2002) Addition of antibiotics has an aim to control lactic acid production mostly over control of Streptococcus bovis and Lactobacillus Spp. (Owens et al 1996). Under normal circumstances, lactic acid is only present in small quantities in the rumen fluid (<5 mmol/l) and is usually controlled by a relatively acid-resistant lactolytic bacterial flora dominated by Megasphera elsdenii and Selenomonas ruminantium and possibly by protozoa (Mackie et al., 1978; Colemann, 1980; Counotte et al., 1983; Mackie et al., 1984; Nagaraja et al., 1992; Williams et al., 1991; Mendoza et al., 1991). Rumen pH is further reduced by the relatively fast and large production of lactic acid (pKa = 3.8) leading to the deterioration of lactolytic bacteria. results in the one-sided favouring of acid-resistant, lactogenic bacterial species such as Lactobacillus spp. and Streptococcus spp. (Mackie et al., 1978). During lactic acidosis direct introduction of micro organisms into rumen during lactic acidosis may have a little value since intrarumaunal pH drastically reduced and these microbes gets killed, giving oral antibiotics during lactic acidosis to prevent the growth of lactic acid bacteria is not specifically kills the other lactic acid utilizing and essential bacteria and protozoa which will further complicate the lactic acidosis.

BACTERIOCINS FROM RUMEN MICROBES:

The rumen represents a complex microbial community, which includes eubacteria, archaea, fungi, and protozoa. The occurrence of bacteriocin-like activities noted among the rumen bacteria to date suggest, that bacteriocin production and resistance of ruminal bacteria to bacteriocins may play an important role in general ecology of the rumen ecosystem (Laukova et al. 1993, Kalmokoff et al. 1997, Morovský et al. 1998, Kalmokoff et al. 1999).

Bacteriocins are antimicrobial peptides produced by bacteria having biologically active moiety with bactericidal activity (Tagg et al., 1976). The product (Jack et al., 1995), Bacteriocin like activity have been demonstrated for number of strict anaerobes (Barefoot et. al .,1993) and facultative anaerobes, (Arihara et al ;1993),and also isolated from non ruminal anaerobic sources, as well as related organisms from rumen (Stewert and Bryant, 1988), including obligate anaerobes from the rumen such as Clostridium species (Cole et al.,1993), Bacteriodes species (Miranda et al.,1993), Bifidobacter species (Barefoot et al.,1993) and Propionobacter species (Iverson et. al.,1976). There is also a report which elaborates the role of bacteriocin in the overall rumen ecology (Atwood et. al., 1988). Bacteriocin like inhibitory substances was found to be produced by strain of Streptococcus bovis (Iverson et al., 1976), number of strains of Enterococci, and Staphylococcoi isolated from calves (Laukova et al ,1993), single isolate of rumen anaerobe Ruminococcus albus (Odenyo et al.,1994), 25 isolates of Butrivibrio fibriosolvens tested for bacteriocin like activity were found to be positive for bacteriocin like inhibitory substances (Kalmokoff et.al., 1996). Butrivibriocin AR10 an antimicrobial peptide identified from rumen anaerobe Butrivibrio fibrisolvens AR10 which was found to inhibit the other Butrivibrio species (Kalmokof and Teather, 1996). Whitford et al., (2001) isolated the antimicrobial peptide from Streptococcus bovis named Bovicin 255. Bacteriocin like activity was identified in Butrivibrio fibriosolvens J15 and other gram positive bacteria (Jennifer and Russel,2002), Pattnaik et al., (2001) identified an antimicrobial peptide named Lichenin from culture supernatant of Bacillus licheniformis obtained from rumen of water Buffalo and it was found to inhibit the growth of Streptococcus bovis SB3 Bovicin HC5 isolated from Streptococcus bovis was found to have antibacterial activity for nisin resistant Streptococcus bovis JB1and even found to inhibit the growth of Listeria monocytogens 104035. (Mantovani et. al., 2002). Junqin et al., (2004) isolated Albusin B from the ruminal bacterium Ruminococcus albus. Production of enterolysin A by rumen Enterococcus faecalis strain was reported by Nigutova et al, (2007) S. bovis is a rapidly growing and opportunistic bacterium that only becomes a dominant ruminal bacterium if the diet contains large amounts of soluble sugar or starch (Hungate, 1966; Owens et al., 1998). Early work indicated that some S. bovis strains produced bacteriocins, but only one of these strains was isolated from the rumen (Iverson and Mills, 1976). Whitford et al. (2001a) screened 35 laboratory cultures, and they noted that approximately 20% of the S. bovis inhibited other streptococci. When fresh isolates from cattle fed hay or grain were overlayed with agar containing S. bovis JB1, approximately 50% of the S. bovis strains produced a zone of clearing (Mantovani et al., 2001). Whitford et al. (2001a) purified a bacteriocin from a bacterium originally thought to be S. bovis, but this isolate and was more closely related to Streptococcus gallolyticus LRC0255 than S. bovis ATCC 33317 (the type strain).

The bacteriocin of LRC0255 (bovicin 255) is a positively charged molecule, and recent work indicated that bovicin 255 could inhibit nisin-sensitive S. bovis but not nisin-resistant cells (Mantovani et al., 2001). When 90 freshly isolated S. bovis were serially diluted into sterile filtered culture supernatant from S. gallolyticus LRC0255, there was only a small decrease in viable cell number (1.8 to 2.1 log cells/ml), and the bovicin sensitive strains adapted. 16S rDNA indicated that a freshly isolated strain designated as HC5 was closely related to other S. bovis, and this strain produced a bacteriocin-like substance that could inhibit nisin-sensitive and nisin-resistant S. bovis JB1 (Mantovani et al., 2001).

Teather and his colleagues purified two butyrivibriocins. The B. fibrisolvens OR79 butyrivibriocin was an lantibiotic, but the other one (from B. fibrisolvens AR10) was homologous to acidocin B, a type IIc bacteriocin produced by Lactobacillus acidophilus (Kalmokoff et al., 1997; Kalmokoff et al., 1999). Both of these butyrivibriocins had relatively wide spectra of activity and were able to inhibit a variety of Gram-positive ruminal bacteria. The . Recent work indicated that a strain identified as B. fibrisolvens JL5 produced a bacteriocin that inhibited B. fibrisolvens AR10, and 16S rDNA analysis indicated that it was distinct from both B. fibrisolvens AR10 and OR79 (Rychlik and Russell, 2002). The JL5 bacteriocin catalyzed potassium efflux from B. fibriosolvens 49 and caused a decrease in ATP and electrical potential across the cell membrane. The JL5 bacteriocin was degraded by Pronase E, but the rate of this degradation was very slow.

Ruminococci are predominant cellulolytics that have been readily isolated from domestic and wild ruminants throughout the world, but in vitro experiments indicated that R. albus and R. flavefaciens could not be co-cultured on cellobiose (Odenyo et al., 1994). R. flavefaciens grew faster on cellobiose than R. albus, but R. albus was the dominant species in co-culture. R. albus 8 produced a heat stable protein factor that caused zones of inhibition in R. flavefaciens FD1 lawns (Odenyo et al., 1994), and subsequent work indicated that other R. albus strains produced bacteriocin-like compounds that could inhibit R. flavefaciens strains and B. fibrisolvens (Chan and Dehority, 1999).

Lactobacilli can be easily isolated from cattle fed grain, but Hungate (1966) concluded that their numbers would not increase until the ruminal pH was already low and S. bovis was inhibited. However, when cattle were adapted gradually in stepwise fashion to rations that had an abundance of cereal grain and soybean meal, there was only a modest decrease in ruminal pH, lactate was never detected and Lactobacilli out-numbered S. bovis (Wells et al., 1997). Because the ruminal pH was always greater than 6.3, the inverse relationship between S. bovis and Lactobacilli could not be explained by pH per se, but subsequent work indicated that many of the lactobacilli produced a substance that could inhibit the growth of laboratory S. bovis strains (Wells et al., 1997). The most active strain was identified as Lactobacillus fermentum, and this species was previously reported to produce a bacteriocin (De Klerk and Smit, 1967).

Enterococcus faecium is not a predominant ruminal bacterium, but bacteriocin-producing E. faecium strains have been isolated from the rumen (Laukova´ and Czikkova´, 1998; Morovsky et al., 1998). E. faecium CCM4231 and BC25 both inhibited S. bovis, but the bacteriocin BC25 appears to have a bacteriostatic rather than bactericidal mode of action. E. faecium BC25 also inhibited CCM4231, but PCR amplification of the BC25 bacteriocin gene (entA) suggested that both strains had the same 726 bp entA homologue.

E.L. Joachimsthal et.al in 2009, identified bovicin Sb15 a Bacteriocin from Streptococcus bovis strain isolated from australian ruminants and shown completely inhibitory to Lactococcus lactis MG1363. Specificity of Bacteriocins: Some bacteriocins have a relatively broad specificity (e.g. nisin) and are able to inhibit a variety of bacteria. The bacteriocin-like activity of S. bovis HC5 (Mantovani et al., 2001) and B. fibrisolvens OR79 inhibited most Gram-positive ruminal bacteria, but butyrivibriocin AR10 was not so broad in its spectrum (Kalmokoff and Teather, 1997). B. fibrisolvens JL5 did not inhibit S. bovis JB1 or many other B. fibrisolvens strains, and Clostridum aminophilum was relatively resistant (Rychlik and Russell, 2002). When Zajdel et al. (1985) treated Lactococcus cremoris 1P5 with trypsin, the cells became 10-fold less sensitive to the lactostrepcin 5 of L. cremoris 202. Nisin was not thought to need a receptor, but recent experiments indicate that it binds to lipid II, and nisin activity in membrane vesicles was enhanced when the amount of lipid II was increased (Breukink et al., 1999). Bacteriocins on Ruminal Ecology: The effect of bacteriocins on ruminal ecology has not been clearly defined. Because bacteriocin-producing and bacteriocin-sensitive strains can be readily isolated from the rumen, the ability of a bacterium to produce a bacteriocin does not confer an absolute growth advantage (Mantovani et al., 2001). Some strains secrete their bacteriocins into the cell-free supernatant, but bacteriocins are more apt to be cell-associated. Because most ruminal bacteria are attached to feed particles, cell associated bacteriocins could be a critical factor in colonization. Continuous culture studies (Shi et al., 1997) and in vivo enumerations based on 16S rDNA probes (Weimer et al., 1999) indicated that R. albus outnumbered R. flavefaciens (a bacteriocin-sensitive species) even though some strains of R. flavefaciens grew faster on cellulose in pure culture than R. albus. Chan and Dehority (1999) noted that inhibitory activity of R. albus strains was decreased or completely destroyed by the proteolytic activity of B. fibrisolvens H15c.

However, these studies were based on culture filtrates, and the impact of B. fibrisolvens in a tri-culture has not been assessed. Acute ruminal acidosis is often caused by an overgrowth of S. bovis, but S. bovis is often replaced by lactobacilli once the ruminal pH is low. Hungate (1966) explained the inverse relationship between S. bovis and lactobacilli by differences in pH sensitivity, but Wells et al. (1997) showed bacteriocin-producing lactobacilli replaced S. bovis even if the ruminal pH was greater than 5.6. Because S. bovis and the lactobacilli both grew rapidly at pH values greater than 5.6, pH sensitivity alone could not explain the shift in bacterial ecology. More recent work indicates that S.bovis strains can also produce bacteriocins (Whitford et al., 2001a; Mantovani et al., 2001), but the impact of S. bovis on lactobacilli has not been addressed. Obligate amino acid fermenting bacteria appear to play a dominant role in wasteful ruminal amino acid deamination (Rychlik and Russell, 2000), but most probable numbers indicate that these bacteria only represented a very small proportion of the total population (Yang and Russell, 1993).

High dilutions of ruminal fluid had glucose-fermenting strains of B. fibrisolvens that produced a bacteriocin, and this bacteriocin inhibited the obligate amino acid fermenting bacteria (Rychlik and Russell, 2002). Because mixed ruminal bacteria from cattle fed grain had a much lower specific activity of ammonia production than bacteria from cattle fed hay, and bacteria from cattle fed grain strongly inhibited the ammonia production of obligate amino acid fermenting bacteria, it appears that bacteriocins could play a role in regulating ruminal ammonia production (Rychlik and Russell, 2000).

EFFECT OF BACTERIOCINS ON LACTIC ACID BACTERIA:

Because some ruminal bacteria can produce bacteriocins, Teather and Forster (1998) speculated that these compounds might provide effective alternatives to antibiotics as feed supplements. because the rumen is a highly diverse bacterial ecosystem inhabited by many different species (and strains within a species) and bacterial competition is very intense (Whitford et al., 1998; Russell and Rychlik, 2001), These bacteriocins like substances should be useful in ruminant production system as an alternative to ionophore antibiotics producing improved feed efficiency, reduced methane production, and lower levels of Trans–saturated fatty acids in dairy products. These bacteriocins can be used as silage inoculants and also useful in food packaging systems to prevent the growth of spoilage bacteria such as Listeria and Clostridia. So far number of antimicrobial peptides has been isolated and characterized from rumen microbes their antimicrobial spectrum also studied most of other ruminal antimicrobial peptides are found be bacteriocin like substances and shown the antimicrobial activity towards Streptococcus bovis an important bacteria which produces lactic acid and causes lactic acidosis In ruminants , some of the important ruminal bacteria and their bacteriocins spectrum of antimicrobial activity towards S. bovis was shown in the table .1

The antimicrobial activity of Sb15 a bacteriocin from Streptococcus bovis was tested against a range of bacteria including normal microflora and species was found to effective against wide spectrum of gram positive bacteria and the highest zone of clearance obtained against Lactococcus lactis an lactic acid bacteria E.L Joachimsthal et al 2009. Hilario C.Mantovani et al in 2002 demonstrated the antimicrobial activity of bovicin HC5 from Streptococcus bovis was found to be effectively inhibited the growth of Streptococcus bovis 3317, Streptococcus bovis15351,and nisin resistant Streptococcus bovisJB1, Patnaik et al in 2001 purified lichenin a bacteriocin like substance from Bacillus licheniformis 26-L/3RA an rumen microbe isolated from water buffalo was found to be completely inhibit the growth of Streptococcus bovis SB3 and Streptococcus bovis 26. Spectrum of BLIS activity against ruminal bacteria.LRC Streptococcus bovis 0253, LRC Streptococcus bovis 0255, and Streptococcus bovis LRC0476 were tested for inhibitory activity in a deferred antagonism assay against a variety of genera of gram-positive and gram-negative bacteria isolated from ruminants. All the three strains produced BLIS that were inhibitory to strains of E. faecium, B. fibrisolvens, and Lactobacillus ruminis. Streptococcus bovis LRC0476 also inhibited a strain of Clostridium perfringens and B. fibrisolvens OB156. Culture supernatants of Ruminococcus albus 7 grown in modified Dehoritymedium with cellulose or cellobiose as a fermentable carbohydrate inhibited growth of R. flavefaciens FD-1 when assayed by a plate culture assay. filtrates of R. albus 7cultures for inhibitory activity toward R. flavefaciens. The spectrum of activity on a selected number of Butyrivibrio and ruminal isolates was evaluated. Several isolates (B. fibrisolvens OR36, B. fibrisolvens OR37, B. fibrisolvens OB146, B. fibrisolvens VV1, which were originally resistant in the indirect plating assay were found to be sensitive to the purified inhibitor. In addition, three isolates B. fibrisolvens OB251, B. fibrisolvens ATCC 19171, and Streptococcus bovis B-b-3 were also sensitive.

The bacteriocin of ruminal bacteria play probably very important role in auto regulation of rumen microbial ecosystem. Use of the native ruminal bactriocins for target modification of ruminal microflora composition, however requires further studies, especially the determination of antimicrobial spectrum of specific bacteriocins against other ruminal commensals, regulation of bacteriocin gene expression and their stability under the actual rumen feeding conditions. These bacteriocins has the ability to inhibit the growth of lactic acid bacteria so they may be used as future tool In preventing lactic acidosis in ruminants.

REFERENCES:

1. Arihara K; Cassens RG and Luchansky JB (1993) Characterization of bacteriocin from Enterococcus faecium with activity against Listeria monocytogens. Int. J. Food Microbiology, 19:123-134.

2. Atwood GT; Lockington RA; Xue GP and Brooker JD (1988) Use of a unique gene sequence as a probe to enumerate a strain of Bacteriodes ruminicola introduced into the rumen . Appl. Environmental Microbiology, 54:534-539.

3. Barefoot SF and Nettles CG (1993) Antibiosis revisited, bacteriocins produced by dairy starter cultures. J. Dairy Science, 76: 2366-2379.

4. Breukink E; Kraaij C; Demel RA; Siezen RJ; Kruijff B and Kuipers OP (1998). The orientation of nisin in membranes. Biochemistry, 37: 8153–8162.

5. Callaway TR; Carneiro De Melo AMS and Russell JB (1997) The effect of nisin and monensin on ruminal fermentations in vitro. Curr Microbiol., 35: 90–96.

6. Chan WW and Dehority BA (1999) Production of Ruminococcus flavefaciens growth inhibitor(s) by Ruminococcus albus. Anim. Feed Sci. Technol., 77: 61–71.

7. De Klerk HC and Smit JA (1967) Properties of a Lactobacillus fermentum bacteriocin. J. Gen Microbiol., 48: 309–316.

8. Dehority BA and Tirabasso PA (2000) Antibiosis between ruminal bacteria and ruminal fungi. Appl. Environ. Microbiol., 66: 2921–2927.

9. Haijie Xiao; Xiuzhu Chen; Meiling Chen; Sha Tang; Xin Zhao and Liandong Huan (2003) Bovicin HJ50, a novel lantibiotic produced Streptococcus bovis HJ 50. Microbiology, 150:103-108.

10. Hungate RE (1950) The anaerobic mesophilic cellulolytic bacteria. Bacteriol. Rev., 14: 1–49.

11. Iverson WG and Mills NF (1976 ) Bacteriocin of Streptococcus bovis . Can. J. Microbiology. 22:1040-1047.

12. Jack RW; Tagg JR and Ray B (1995) Bacteriocin of Gram positive bacteria. Microbiology Rev., 59:171-200.

13. Jennifer L Rychlik and James B Russel (2002) Bacteriocin like activity of Butrivibrio fibrosolvens JL5 and its effect on other Ruminal Bacteria and Ammonia Production. Applied and Environmental Microbiology, 68:1040-1046.

14. Junqin Chen; Dravid M; Stevenson and Paul J Weimer (2004) Albusin B a Bacteriocin from the Ruminal Bacterium Ruminococcus albus 7 that inhibits the Growth of Ruminoccocus flavifaciens. Applied and Environmental Microbiology, 70:3167-3170.

15. Nigutova K; Morovsky M; Pristas P; Teather RM; Holo H; Javorsky P (2007) Production of enterolysin A by rumen Enterococcus faecalis strain and occurrence of enlA homologues among ruminal Gram-positive cocci. Journal of Applied Microbiology, 102 (2):563–569.

16. Kalmokoff ML; Lu D; Whitford MF and Teather RM (1999) Evidence for production of a new lantibiotic (Butrvibriocin OR79A) by the ruminal anaerobe Butrivibrio fibriosolvens OR79A, characterization of structural gene encoding Butrvibriocin OR79A. Applied and Environmental Microbiology, 65:2128-2135.

17. Kalmokoff ML; Bartlett F and Teather RM (1996) Are ruminal bacteria armed with bacteriocins? J. Dairy Sci., 79:2297-2306

18. Kalmokoff ML and Teather RM (1997) Isolation and characterization of a bacteriocin (butyrivibriocin AR10) from the ruminal anaerobe Butyrivibrio fibrisolvens AR10.Evidence in support of widespread occurrence of bacteriocin-like activity among ruminal isolates of B. fibrisolvens. Appl. Environ. Microbiol., 63: 394–402.

19. Mantovani HC and Russell JB (2001) Nisin resistance of Streptococcus bovis. Appl. Environ. Microbiol., 67: 808–813.

20. Mantovani HC and Russell JB (2002) Factors affecting the antibacterial activity of the ruminal bacterium, Streptococcus bovis HC5. Curr. Microbiol.

21. Mantovani HC; Kam DK; Ha JK and Russell JB (2001) The antibacterial activity and sensitivity of Streptococcus bovis strains isolated from the rumen of cattle. FEMS Microbial Ecol., 37: 223–229.

22. Mantovani HC; Haijing Hu; Worobo RW and Russel JB (2002) Bovicin HC5 a bactreiocin from Streptococcus bovis HC5, Microbiology, 148:3347-3352.

23. Owens FN; Secrist DS; Hill WJ and Gill DR (1998) Acidosis in cattle: A review. J. Anim Sci., 76: 275–286.

24. Pattnaik P; Kaushik JK; Grover S and Batish VK (2001) Purification and haracterization of bacteriocin like compound (Lichenin) produced anaerobically by Bacillus licheniformis isolated from water Buffalo. Journal of Applied Microbiology, 91: 636-645.

25. Teather RM and Forster RJ (1998) Manipulating the rumen microflora with bacteriocins to improve ruminant production. Can. J. Anim. Sci., 78: 57–69.

26. Whitford MF; McPherson MA; Forster RJ and Teather RM (2001a)Identification of bacteriocin-like inhibitors from rumen Streptococcus sp. and isolation and characterization of bovicin 255. Appl. Environ. Microbiol., 67:569–574.

27. 26 Ravi Kumar, K., Thanislass, J.

, Suneetha, V., Antony, P.X., Partial purification of bacteriocin like substance from rumen liquor obtained from the slaughtered cattle for medical applications Asian J Pharm Clin Res, Vol 6 Suppl 5, 2013, 180-183

27.

Received on 09.08.2014 Modified on 14.09.2014

Research J. Science and Tech. 6(4): Oct. - Dec.2014; Page 220-224