New Perspectives on the Control of. and Related Enteric Pathogens

Transcription

1 Diamond V Welcomes You to the 4-State Pre-Conference New Perspectives on the Control of Salmonella and Related Enteric Pathogens Steve A. Carlson, DVM PhD Associate Professor of Molecular Pharmacology Iowa State University College of Veterinary Medicine (I) ImportanceofSalmonella incattle New Perspectives on the Control of Salmonella and Related Enteric Pathogens Steve A. Carlson, DVM PhD Associate Professor of Molecular Pharmacology Iowa State University College of Veterinary Medicine Threeimportantfacets: (A)Attachmenttothegut epithelium (B)Invasionofcellsliningthegut epithelium ih (C)Survivalwithinbovine macrophages (I) OverviewofthePresentation TheimportanceofSalmonella incattle (II) StrategiestomitigateSalmonella Salmonella incattle (III) Newapproachesthatusetheanti the antisalmonella strategies (IV) Costeffectivenessoftheseapproaches (V) Conclusions (I) ImportanceofSalmonella incattle (B)Physicalinvasionofthegutepitheliumandentranceintothe systemiccirculation circulation SomeSalmonellaSalmonella caninvadeanddislodgecellsliningthebovine gutepithelium epithelium causingahemorrhagicdiarrhea. a 1

2 (I) ImportanceofSalmonella incattle (B) Invasion of intestinal cells (i) Attachment (ii) Injection of bacterial proteins (iii) Rearrangement of actin (iv) Formation of a ruffle (v) Bacterial entry into the cell (vi) Cell is damaged and sloughs (vii) Underlying vasculature is exposed (viii) Hemorrhagic diarrhea (I) ImportanceofSalmonella incattle (II) StrategiestomitigateSalmonellaSalmonella incattle Lessinvasivestrainswill causeamoderatediarrhea incalves. Costlybecauseofmedical costsandhamperedgrowth anddevelopment (A)Selectingforcattlethatarenaturally resistant (B)Alteringgeneexpressionincattle (C)AlteringgeneexpressioninSalmonella (D)Directlykilling killingsalmonella Salmonellawithantibiotics Theanimalbecomesalife longcarrier. (I) ImportanceofSalmonella incattle (C)Survivalwithinbovinemacrophages (whitebloodcells) ll MacrophageswillengulfSalmonella onthe basalsideoftheintestinallining. side intestinal lining Salmonella surviveswithinthemacrophages. ThemacrophagescarrytheSalmonellatoato organslikethelung(pneumonia)orbrain (encephalitis). ThemacrophagesalsocarrytheSalmonella tolymphnodes,causingafoodsafety hazard. (II) StrategiestomitigateSalmonellaSalmonella incattle (A)Selectingforcattlethatarenaturallyresistant Salmonella exploitsproteinswithinintestinalcellsand proteins intestinal and macrophagesduringtheintestinalinvasionandmacrophage survivalprocesses. Minimizingtheseproteinswillleadtoadecreasedsusceptibility tosalmonella infections. Certaincattleharboruniquegenesthatleadtominimized expressionoftheseproteinsexploitedbysalmonella Salmonella. Normal expression of the exploited proteins Reduced expression of the exploited proteins 2

3 (II) StrategiestomitigateSalmonella Salmonella incattle (B)Alteringgeneexpressionincattle Itispossiblethatexogenouscompounds(e.g that exogenous e.g.,fromsupplements) eg.,fromsupplements) willreducetheexpressionoftheproteinsexploitedby Salmonella. Thisphenomenonistermedan epigenetic changewherethe geneticsofananimalarenotalteredbutthegeneexpression patternistransientlyaltered. transiently altered (III) Newlyavailableapproachesformitigating Salmonella incattle (A)Selectingforcattlewithnaturalresistance PSRGeneticsLLC (B)Alteringgeneexpressionincattle DiamondVproducts (C)AlteringgenesinnSalmonella DiamondVproducts ThesecosteffectiveapproachesmitigateeSalmonella without instigatingabiofilm,thusavoidingthepotentialforresistance. Normal expression of the exploited proteins supplement Reduced expression of the exploited proteins *Product image courtesy of Diamond V *Product image courtesy of Diamond V SmartCare is registered trademark and Original XPC is a trademark of Diamond V Mills, Inc. (II) StrategiestomitigateSalmonella Salmonella incattle (C)AlteringgeneexpressioninSalmonella Asmentioned,Salmonella injectsaseriesofproteinsintothe series into the intestinalcellsduringtheinvasionprocess. Minimizingtheexpressionoftheseproteinswillleadtoa expression of these proteins lead to a decreaseinsalmonella virulence. Thisspecificdecreaseinexpressionisanoutcomeofchangesin p thechemicaland/ormicrobiologicprofileofthegut. (III) Newlyavailableapproachesformitigating Salmonella incattle (A)Selectingforcattlethatarenaturallyresistant PSRGeneticsLLCidentifiedacattlegenotypeconferringnatural resistancetosalmonella. Thisgenotypeleadstoreducedexpressionoftheintestinaland macrophageproteinsexploitedbysalmonella. About35%ofnonblackcattlepossessthisgenotype,while5%of blackcattlepossessthisgenotype,while5%of l hil blackcattlehaveananalogousresistanceconferringgenotype.conferringgenotype. Invasion Changes in the gut No invasion (II) StrategiestomitigateSalmonella Salmonella incattle (D)DirectlykillingSalmonellawithantibiotics AntibioticskillSalmonella Salmonellabyperturbingvitalprocessesinthe processes the bacteria. Unfortunately,Salmonella willformabiofilminwhicha in which a subpopulationareprotectedfromexposuretotheantibiotic. Ultimately,thiswillleadtoantibioticresistance. Protected bacteria (III) Newlyavailableapproachesformitigating Salmonella incattle (A)Selectingforcattlethatarenaturallyresistant EUTHANASIA CLINICAL SIGNS LIVES.n. Sn inblood S.n. in feces S.n. DNA inblood NOTRACE of S.n. psr/psr PSR/psr PSR/PSR Days postinfection infectionwithvirulent mr S.newport Thereisadirect correlationbetweenthe presenceofthepsr geneandsusceptibility oflivecattleto to Salmonella infection. Even10Xthechallenge dosecouldnotproduce illnessoranysheddingof Salmonella inthefecesin thesecattle. 3

4 (III) Newlyavailableapproachesfor mitigatingsalmonella incattle (A)Selectingforcattlethatarenaturallyresistant escontam minated LymphNod %ofl AllOtherGenotypes SuperficialCervical Subiliac Popliteal PSR/PSR Theperipherallymphnodes ofpsr/psrcattle arenotsusceptibleto to contaminationby twoof thesalmonella strains implicatedinthisemerging problem. (III) Newlyavailableapproachesfor mitigatingsalmonella incattle Proprietaryactivecompoundsds DVBioactives thatlikely supportimmunefunction Availableforincorporationinto 0.15%)andstarterfeed(Original XPC@3.5gm/head/day) Recentblindedstudies demonstratethatthese productspreventtheuntoward effectsofs.typhimurium in dairycalvesonmilk. SmartCare is registered trademark and Original XPC is a trademark of Diamond V Mills, Inc. HowdoesthePSR/PSR PSR/PSRgenotypeinhibitSalmonella? DiamondV ssmartcare &OriginalXPC Fornonblackcattle,theseanimallackoneproteinexploitedby Salmonella duringtheinvasionprocessandtheylackoneprotein exploitedbysalmonella duringthemacrophagesurvivalprocess. Forblackcattle,theseanimalshaveadiminishedexpressionof 36proteinsexploitedbyS 6proteinsexploitedbySalmonella i db Salmonella. ll Agenetictestisavailableforidentifyingandpropagatingcattle containingthegenotype. the genotype Calveswerefedthese productsfortwoweeks thenchallengedwiths. h Typhimurium. Calveswerefedthese productsforanother threeweeksduring whichvariousclinical parameterswere measured. TheDVBioactives (SCFP)significantly diminishedthe incidenceoffever. (III) Newlyavailableapproachesformitigating Salmonella incattle DiamondV ssmartcare &OriginalXPC (B)Alteringgeneexpressionincattle DiamondVproducts (C) AlteringgenesinSalmonellagenes DiamondV DiamondVproducts (i)calfdiarrhea( )Calfdiarrhea(Salmonella ande.coli EcoliK99) E.coliK99) K99) DiamondV SmartCare &OriginalXPC (ii)adultsalmonellosis () PrototypeNaturSafe (iii)lymphnodepersistence PrototypeNaturSafe DVBioactives significantly diminishedthe severityand incidenceof diarrhea throughoutthe study. Brewer et al

5 DiamondV ssmartcare &OriginalXPC DiamondV ssmartcare &OriginalXPC DVBioactives significantlydiminished ifi i i d theprevalenceofcalves sheddingsalmonella in theirfeces. DVBioactives significantlyincreased ifi i weightgainduringthe trial. (I) DiamondV ssmartcare &OriginalXPC MitigatingAdultBovineSalmonellosis DVBioactives significantly diminishedthe i i d prevalenceofcalves sheddingsalmonella intheirfeces. DiamondVislaunchinga next generation product(nutritek )for useindairycattle. i DiamondVisworkingonasimilar technologytobeusedinbeefcattle to beef cattle (NaturSafe). Despite thefinding thatthedvfedcalves harboredfewer df Salmonella intheir ileaattheendofthe study. Ourinvestigator investigatorblinded blindedstudieswith NaturSafe revealsaprotectiveeffect againstsalmonellosis. N=200animalspergroup;naturally infectedwithvarioussalmonella; Controlincludesanantibiotic antibiotic NutriTek is registered trademark of Diamond V Mills, Inc. DiamondV ssmartcare &OriginalXPC DVBioactives significantlyincreased thelengthofrumen papillae. Control Materials and Methods Treatments Positive Control Monensin at 300 mg/head/day, Tylosin at 90 mg/head/day, and Direct fed microbial at 50 mg/head/d NaturSafe Supplemented at rate18 g/head/d No monensin, tylosin, or a direct fed microbial SCFP 5

6 Materials and Methods Liver Abscesses Liver abscess Classifications With O No abscesses With A - or A 1 to 2 small abscesses Up to 2 to 4 well organized abscesses With A+ Multiple large abscesses Tissue inflammation around abscess and adhesions Brown et al J. Anim. Sci. 40: O A A - A + Positive Control 1 NaturSafe SEM P-value Carcasses, n Liver abscesses, % A A A Total Condemned Positive Control contains monensin, tylosin, and a direct fed microbial. These are not included in diet of DV Prototype. Overview Positive Control 1 NaturSafe Heifers, n Pens, n MitigatingAdultBovineSalmonellosis NaturSafe ledtoadecreaseinthepresenceofsalmonella inthe feces. feces. Days on feed Bunk space, in/head Pen space, ft 2 /head Positive Control contains monensin, tylosin, and a direct fed microbial. These are not included in diet of DV Prototype. Performance Positive Control 1 DV Prototype SEM P-value Body weight, lb Initial Final 2 1,278 1, ADG, lb/day DMI, lb/day Feed efficiency (DMC) Salmonella invasion assays Yield adjusted Final BW, lb 3 1,266 1, ADG, lb/day Feed efficiency Salmonella Isolates Tissue culture cells Invaded cell 1 Positive Control contains monensin, tylosin, and a direct fed microbial. These are not included in diet of DV Prototype; 2 Final BW shrunk 4%; 3 Yield adjusted BW calculated by dividing HCW by a common dressing yield of Recover and count Salmonella in cells 6

7 MitigatingAdultBovineSalmonellosis NaturSafe ledtoadecreaseintheinvasivenessofsalmonella recoveredfromfeces. HowaretheDiamondVproductsreducingthe presenceofsalmonella? StudiesfromotherspeciesrevealthattheDiamondV productsrebalancetheimmunesystem,by epigeneticallyactivatinggeneexpressionevents. Thisrebalancingallowstheimmunesystemto ll h appropriatelyandefficientlyrespondtopathogens. ThislikelyfacilitatesanenhancedkillingofSalmonella l ilit t h killi f l ll withinmacrophages. Since Salmonellacannotformbiofilmswithin macrophages,thechanceforresistanceisminimal. MitigatingLymphNodeInfiltration NaturSafe ledtoadecreasedloadofsalmonella insubiliac lymph nodes. MitigatingLymphNodeInfiltration NaturSafe ledtoadecreasedprevalenceofsalmonella insubiliac lymphnodes. 7

8 HowaretheDiamondVproductsinhibitingthe invasiveness(andthusvirulence)ofsalmonella? virulence) DiamondVBioactives altertheruminal ruminal andintestinal microbiomes. Themicrobialalterationsleadtoepigeneticchanges insalmonella,alteringitsinvasivenessandvirulence. OurstudiesrevealedthatmultipleDiamondV productsarecapableofinhibitingtheexpressionof themajorsalmonella invasionregulatinggene designatedashila hila. (IV)CostEffectivenessoftheNewMitigationoftheNewMitigation ApproachesforSalmonella incattle SmartCare andoriginalxpcareusefulantibioticfreefeedand freefeedand milkreplaceradditivesforcombatingsalmonellosisinpre additives combating salmonellosis in preweaned weaned dairycalves,whilealsoenhancinggrowth. SmartCare is registered trademark and Original XPC is a trademark of Diamond V Mills, Inc. *Product images courtesy of Diamond v AntiResistancePropertiesoftheNewApproachesfor Salmonella incattle CattlelackingaproteinexploitedbySalmonella Salmonella thebacteriawill simplygoelsewhere. l KillingSalmonella inmacrophageswherebiofilmscannotexist no chanceforresistance. resistance Inhibitingvirulence notadverseforsalmonella sinceithasthe optiontoadoptornotadoptthepathogeniclifestyle;no to or not the pathogenic no resistanceresponse. (IV)CostEffectivenessoftheNewMitigationoftheNewMitigation ApproachesforSalmonella incattle NaturSafe hassimilarantisalmonella propertiesinadultcattle. Positive Control 1 NaturSafe SEM P-value Carcasses, n Liver abscesses, % A A A Total Condemned

9 (V) SummaryoftheNewMitigationApproaches forsalmonella incattle ThePSR geneisacosteffectiveselection effectiveselectiontoolfortoolfor Salmonellaresistantcattle. ll it t ttl SmartCareandOriginalXPCareusefulantibioticfree free feedandmilkreplaceradditivesforcombating additives for combating salmonellosisinpreweaneddairy weaneddairycalves,whilealso enhancingproduction. NaturSafe hassimilarpropertiesandisforusein beefcattle. NutriTek istheadultdairyspecificversionofthe specificversionofthe aforementionedproductsand,givenitsrelatedness totheseproducts,hasthesameproductionandanti these has the same production and anti pathogentraits. 9