14 International Pig Topics — Volume 29 Number 7

by Alvaro Ortiz, Norel SA,Barcelona, Spain.

Health control has alwaysbeen a major concern in pigfarms. The gut is a very cru-

cial organ for maintaining animalhealth. Apart from absorbing nutri-ents, the gut is also the barrieragainst unwanted compounds andgerms. The immune system in theintestine plays an important role inthis. Immune cells such as inflamma-tory cells were thought to be cen-tral, and until recently, theenterocyte layer was considered asimple physical barrier.Nowadays, it is known that ente-

rocytes are immunocompetent cellsas well, in particular in the innatepart of the immune system. Enterocytes play an important role

in the crosstalk with intestinal micro-biota. Enterocytes, dendritic cellsand macrophages are involved inachieving a balanced response. Furthermore, the presence of

numerous nerve endings suggestsinvolvement of the central nervoussystem.

Risk factors

As the intestines are constantlyexposed to foreign substances suchas feed, it is not surprising that thebody has evolved an intestinal sys-tem to control inflammation andimmunity. However, this mechanismcan be overwhelmed by risk factors.One of the best studied disturbingfactors is weaning. In this period,piglets suffer an important alterationto the intestinal wall.

Abrupt separation from themother, cross-fostering, transportsand change to a solid feed, which inmost of the cases is more difficult todigest, are some of the challengesthat weaned piglets must face. Thehighly digestible nutrients in milk aresubstituted by complex carbohy-drates and proteins mainly from veg-etable origin. In consequence, feedintake drops during the first weekafter weaning and the scarce bodyreserves are mobilised.Villi height is reduced and the pro-

portion of immature enterocytesincreases, therefore the enzymaticactivity of the gut is reduced. Thegut microflora also suffers from thissituation, Lactobacilli populationdecreases and at the same time E.coli numbers increase due to theabundance of undigested fer-mentable substrates in the intestine.This scenario results in a major

imbalance in gut homeostasis thatcauses digestion and nutrientabsorption problems and diarrhoea.In this context, the modulation ofgut microflora as a tool to amelio-rate these stressing circumstancesarises as a suitable strategy.The intestinal microbiome of the

animal host is a complex ecologicsystem that produces a significantimpact on the host. Aerobic andanaerobic bacteria of the intestinalflora influence numerous anatomic,physiologic, and immunologic para-meters.Normal intestinal flora consists of

a diverse population of bacteriacompeting for survival and repre-sents an important natural defencemechanism.An early supplementation with

DFM (Direct Fed Micro-organisms)can help control the gut microbiotaavoiding undesirable imbalances.The mechanisms used by probioticsto enhance gut health are numerous.In this case we will focus on lacticbacteria.

Lactic acid bacteria

Lactic acid bacteria (LAB) is theterm used to denominate the groupof micro-organisms capable of pro-ducing lactic acid through sugar’sfermentative metabolism. Lactic acidacidification capacity is higher thanthat of most organic acids and there-fore inhibits the proliferation ofpathogenic bacteria in the gastro-intestinal tract.Lactobacillus genus is the most

abundant LAB in healthy animals’small intestine. The main inconve-nience is that this genus shows a lowgrowth rate and they perish if thepH increases above a certain level.The vulnerability of this genus makesit unsuitable to modulate intestinalmicroflora in stressful situations.Enterococcus faecium is another

well known LAB. Being a typical bac-teria present in animals’ gut, it has ahigher growth rate and a betterresilience to adverse ambience.This bacteria presents superim-

posed layers of polysaccharides onits surface that permits them to passthrough the stomach without beingaffected by the acid pH. Once they reach the intestine,

they multiply at a rapid rate (dou-bling in CFU count every 19 min-

utes), and adhere to the intestineepithelium forming together withlactobacilli, the ‘biological barrier’ toprotect the body against disease-causing germs.The fast rate of colonisation and

affinity for the environment makes itpossible for E. faecium to success-fully compete with the enterobacte-ria for the loci and nutrients in theintestinal environment, rapidly form-ing the protective coating and thuspreventing undesired bacteria frommultiplying.In addition, it has been proven that

during its multiplication, E faeciumproduces a large quantity ofenzymes in sufficient amounts tomake feed nutrients more digestible.Most part of acid production by

the fermentative metabolism of E.faecium corresponds to L-lactic.However acetic and D-lactic acidscan also be found.More than half of the available sug-

ars can be transformed to acids byE. faecium. Besides the antibacterialeffect, these acids can be used tocontrol the intestinal pH (pathogensbio-control) and/or as carbonsource and available energy.The lactic acid formed in the

intestinal tract penetrates the non-lactic enterobacteria (Gram nega-tive) and then reacts inside, beingconverted into lactate, affecting theproteins and DNA of the bacteriaoxidising them. This also causes areduction of the intracellular pH inthe bacteria cells, disrupting theirmetabolism.Lactic acid also reduces the exter-

nal pH to levels which are damaging

Table 1. Multiplication of micro-organisms.

Table 2. Performance results.

The important role of the immune system in gut health

Micro-organism Time to double population (mins)

Lactobacillus acidophilus 64

Lactobacillus bulgaricus 40

Streptococcus thermophilus 46

Enterococcus faecium CECT 4515 19

Escherichia coli 18-20

Bacillus subtilis 60

Saccharomyces cerevisiae 200

Pre-starter Starter Overall

ADG

Control 84 371 276

Fecinor 91 436 324

ADFI

Control 179 615 470

Fecinor 179 662 501

FCR

Control 2.33 1.69 1.79

Fecinor 2.19 1.53 1.56

14,15, Intestinal balance (Norel) 06/10/2014 Week 41 14:45 Page 1

International Pig Topics — Volume 29 Number 7 15

for many enterobacteria. The dropin the pH in the digestive tract alsopromotes the conversion ofpepsinogen into pepsin in young ani-mals, thus increasing the endoge-nous proteolytic capacity. This bacteria also produces differ-ent enzymes in sufficient amounts toincrease the digestibility of the feed.Proteases, lipases, amylases andsome disaccharidases (for examplea-glycosidase, invertase, etc) areproduced in significant amounts.E. faecium seems to also have animpact on the active transport ofnutrients, especially when this mech-anism is impaired by salmonellainfection. An increase in glucose andphosphorus uptake from thejejunum was observed in a recentstudy in which salmonella challengedanimals were treated with E. fae-cium. The supplementation in the wean-ing period with a high growth rateLAB makes the adaptation to thenew condition easier for piglets.Having a healthier gut with a propermicroflora and an active proteolyticcapacity makes the processsmoother. Trying to confirm these effects,Norel SA conducted a trial in a com-mercial farm in Spain.A total of 144 animals were

enrolled in the test, a standard dietwithout any kind of medication wasused and half of the animals were

supplemented with 1kg/t of Fecinor(E. faecium CECT 4515 1x109

CFU/g). Regular performance para-meters were monitored such asbody weight, feed intake, culling andmortality. Average Daily Feed Intake (ADFI),Average Daily Growth (ADG) andFeed Conversion Rate (FCR) werecalculated accordingly.Furthermore, 72 pigs housed in 12pens (six replicates per group) werefed diets mixed with chromic oxidefrom day 7 to 14 and from day 35 to42. Then, faecal samples were col-lected daily for three days fromevery pen, to determine the

Apparent Total Tract Digestibility(ATTD) of dry matter (DM), crudeprotein (CP) and gross energy (GE).As can be observed in Table 2,overall growth rates (ADG) of theanimals fed Fecinor were higher thanthe negative control group (p>0.05).Feed consumption was similarbetween groups, therefore feed effi-ciency was improved by Fecinor(p<0.05).Apparent total tract digestibilitiesof the dry matter, crude protein andgross energy tended to improvewith Fecinor (p<0.10) at the end ofthe nursery period (from days 40-42post-weaning).

It was concluded that Fecinorresulted in better performance vari-ables. It could be explained, according tothe study results, by the betterdigestibilities achieved by animalsreceiving Fecinor.In summary, the benefits of usingFecinor are:l Naturally found in the intestine,which makes it more environment-friendly. High replication rate com-pared to other LAB or yeasts.l Forms a protective coating on theintestinal epithelium, thus contribut-ing to avoid the development of thepathogenic bacteria.l Produces large amounts ofenzymes, especially proteases andamylases.l Synthesises large quantities of lac-tic acid, a well known pathogenantagonist, and at the same time areadily absorbed energy source.l Enhances the effects of endoge-nous proteolytic enzymes in theintestine.l Improves production parameters.Average daily weight gain and feedconversion ratio.l Helps in restoring the intestinalflora following treatments withantibiotics and in situations of stress. n

References are available from the author on request

Fig. 1. Digestibilities of dry matter, crude protein and gross energy.

Dry matter Crude protein Gross energy

92

90

88

86

84

82

80

78

76

74

n Control n Fecinor

Percentage (%)

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