What’s Your Dead Pile TellingWhat’s Your Dead Pile TellingWhat s Your Dead Pile Telling What s Your Dead Pile Telling You About Your HealthYou About Your HealthYou About Your Health You About Your Health

Program?Program?

Dr John CampbellDr John CampbellDr. John CampbellDr. John Campbell2007 Beef Symposium2007 Beef Symposium

Causes of mortality based on gross Causes of mortality based on gross necropsy in study group (n=277)necropsy in study group (n=277)

BVD7%

UNKNOWN7%

BRD17%

AIP4%

OTHER10%

4%

CPPS

HEMOPHILOSIS19%

CPPS28%DIGESTIVE

8%

Chronic Pneumonia Polyarthritis Chronic Pneumonia Polyarthritis SyndromeSyndromeSyndromeSyndrome

Mycoplasma BovisMycoplasma Bovisy py p

The MycoplasmasThe MycoplasmasThe MycoplasmasThe MycoplasmasMycoplasmas are Mycoplasmas are unusual selfunusual self--replicating replicating bacteria (Classbacteria (Classbacteria (Class bacteria (Class Mollicutes)Mollicutes)No cell wallNo cell wallNo cell wallNo cell wallPerhaps one of the Perhaps one of the smallest and simplest of smallest and simplest of s a est a d s p est os a est a d s p est oself replicating organismsself replicating organismsRequire cholesterol for Require cholesterol for qqmembrane function and membrane function and growthgrowth

The MycoplasmasThe MycoplasmasThe MycoplasmasThe MycoplasmasR l ti l h t ifiR l ti l h t ifiRelatively host specificRelatively host specificSome mycoplasma organisms (including M. Some mycoplasma organisms (including M. b i ) h th bilit t f bi filb i ) h th bilit t f bi filbovis) have the ability to form biofilmsbovis) have the ability to form biofilms–– Environmental survival?Environmental survival?

R i i l lt di thR i i l lt di thRequire special culture media, growth Require special culture media, growth substances and conditionssubstances and conditionsR i l i b ti i d th thR i l i b ti i d th thRequire longer incubation periods than other Require longer incubation periods than other bacterial pathogensbacterial pathogensS i l l i l t t tS i l l i l t t tSpecial serological tests are necessary to Special serological tests are necessary to perform species differentiation on colonyperform species differentiation on colony

Mycoplasma: A controversial Mycoplasma: A controversial organismorganismorganismorganism

Many recently proposed Many recently proposed y y p py y p pcontroversial associations of controversial associations of mycoplasmas to various human mycoplasmas to various human y py pdiseasesdiseases–– Accelerating the progression of AIDSAccelerating the progression of AIDSAccelerating the progression of AIDSAccelerating the progression of AIDS–– Malignant transformation of cellsMalignant transformation of cells

Crohns diseaseCrohns disease–– Crohns diseaseCrohns disease–– Gulf War SyndromeGulf War Syndrome

Rh t id A th iti d th HRh t id A th iti d th H–– Rheumatoid Arthritis and other Human Rheumatoid Arthritis and other Human ArthritidesArthritides

Mycoplasma mycoides subsp Mycoplasma mycoides subsp mycoidesmycoides

C t i B iC t i B iContagious Bovine Contagious Bovine pleuropneumoniapleuropneumoniaSeen in at least 29 countries inSeen in at least 29 countries inSeen in at least 29 countries in Seen in at least 29 countries in AfricaAfricaEradicated from Europe around Eradicated from Europe around ppthe end of the 19the end of the 19thth centurycenturyOccasional outbreaks in Europe Occasional outbreaks in Europe in the 90’s in Spain Italy andin the 90’s in Spain Italy andin the 90 s in Spain, Italy and in the 90 s in Spain, Italy and FranceFranceLargely controlled by abattoirLargely controlled by abattoirLargely controlled by abattoir Largely controlled by abattoir surveillance and blood testingsurveillance and blood testingNo effective vaccinesNo effective vaccines

Mycoplasma bovisMycoplasma bovisMycoplasma bovisMycoplasma bovisRecognized as the Recognized as the most invasive and most invasive and destructive of bovine destructive of bovine mycoplasmas in North mycoplasmas in North AmericaAmericaAssociated with a Associated with a number of syndromesnumber of syndromesyy–– PneumoniaPneumonia–– Polyarthritis, tenosynovitisPolyarthritis, tenosynovitis–– Mastitis in adult dairy cattleMastitis in adult dairy cattle–– Inner ear infections in dairy Inner ear infections in dairy

calvescalvescalvescalves–– Eye infectionsEye infections

Economic CostsEconomic CostsEconomic CostsEconomic Costs

In USA costs of M. bovis causing In USA costs of M. bovis causing respiratory disease, loss of weight gain respiratory disease, loss of weight gain p y , g gp y , g gand carcass value have been estimate at and carcass value have been estimate at $32 million per year$32 million per year$32 million per year$32 million per yearLosses due to bovine mastitis in the USA Losses due to bovine mastitis in the USA

$$have been estimated at close to $108 have been estimated at close to $108 million per yearmillion per yearp yp y

Prevalence of M bovisPrevalence of M bovisPrevalence of M. bovisPrevalence of M. bovis

O i i i l t d f tl fO i i i l t d f tl fOrganism is isolated frequently from Organism is isolated frequently from feedlot calvesfeedlot calves–– Found in normal and pneumonic lungsFound in normal and pneumonic lungs

Allen et al, Can J Vet Res 1992:Allen et al, Can J Vet Res 1992:Allen et al, Can J Vet Res 1992: Allen et al, Can J Vet Res 1992: –– Nasopharyngeal swabs and BA lavage from Nasopharyngeal swabs and BA lavage from

59 BRD cases and 60 control calves entering59 BRD cases and 60 control calves entering59 BRD cases and 60 control calves entering 59 BRD cases and 60 control calves entering an Ontario research feedlotan Ontario research feedlot

–– When a BRD case was selected, the caseWhen a BRD case was selected, the caseWhen a BRD case was selected, the case When a BRD case was selected, the case and a control calf would be sampled and then and a control calf would be sampled and then subsequently followed up with other samplessubsequently followed up with other samplesyy

Prevalence of M. bovis in feedlot Prevalence of M. bovis in feedlot calvescalves

Nasopharyngeal Nasopharyngeal SamplesSamples

BAL SamplesBAL SamplesSamplesSamplesCasesCases ControlsControls CasesCases ControlsControls

Day 1Day 1 80%80% 40%40% 60%60% 48%48%

Day 12Day 12 98%98% 92%92% 100%100% 80%80%

Allen et al, Can J Vet Res 1992J

Is it a pathogen or normal flora?Is it a pathogen or normal flora?Is it a pathogen or normal flora?Is it a pathogen or normal flora?

It ld th t hi h tiIt ld th t hi h tiIt would appear that a very high proportion It would appear that a very high proportion of feedlot calves are exposed to M. bovisof feedlot calves are exposed to M. bovisEvades normal lung clearance Evades normal lung clearance mechanismsmechanismsIs it a persistent infection or temporary? Is it a persistent infection or temporary?

How long?: Several weeks or months?How long?: Several weeks or months?–– How long?: Several weeks or months?How long?: Several weeks or months?Some evidence that infected cattle shed Some evidence that infected cattle shed th i f thth i f ththe organism for months or even yearsthe organism for months or even yearsMay act as reservoirs of infectionMay act as reservoirs of infectionyy

Is it a pathogen or normal flora?Is it a pathogen or normal flora?Is it a pathogen or normal flora?Is it a pathogen or normal flora?

Associated with an increased proportion of Associated with an increased proportion of inflammatory cells in BAL fluidinflammatory cells in BAL fluidyyMycoplasma bovis was cultured from all Mycoplasma bovis was cultured from all nonresponders and relapsersnonresponders and relapsersnonresponders and relapsersnonresponders and relapsersNo other organisms were cultured from No other organisms were cultured from nonnon--respondersresponders

Allen et al, Can J Vet Res, 1992

Seroepidemiological evidence?Seroepidemiological evidence?Seroepidemiological evidence?Seroepidemiological evidence?Martin et al Can J Vet Res 1989Martin et al Can J Vet Res 1989Martin et al, Can J Vet Res 1989Martin et al, Can J Vet Res 1989Prevalence of titers to M. bovis at arrival to Prevalence of titers to M. bovis at arrival to feedlot was approximately 70%feedlot was approximately 70%Approximately 45% of calvesApproximately 45% of calvesApproximately 45% of calves Approximately 45% of calves seroconverted to M. bovis by day 28seroconverted to M. bovis by day 28Cases had significantly higher titers at Cases had significantly higher titers at arrivalarrivalConcluded that there was a lack of Concluded that there was a lack of evidence to support an etiological role forevidence to support an etiological role forevidence to support an etiological role for evidence to support an etiological role for M. bovisM. bovis

Seroepidemiological evidence?Seroepidemiological evidence?Seroepidemiological evidence?Seroepidemiological evidence?

Martin et al, Can Vet J; 1999Martin et al, Can Vet J; 1999Case control study sampling feedlot calvesCase control study sampling feedlot calvesCase control study sampling feedlot calves Case control study sampling feedlot calves in Alberta and Ontarioin Alberta and Ontario5% f l iti f M5% f l iti f M5% of calves were seropositive for M. 5% of calves were seropositive for M. bovis at arrivalbovis at arrivalOnly 14% of calves seroconverted to M. Only 14% of calves seroconverted to M. bovisbovisbovisbovisSuggested M. bovis was not widespread Suggested M. bovis was not widespread and not associated with BRDand not associated with BRD

The Chronic PneumoniaThe Chronic Pneumonia--Polyarthritis SyndromePolyarthritis Syndrome

O tb k f i d/ l th itiO tb k f i d/ l th itiOutbreaks of pneumonia and/or polyarthritis Outbreaks of pneumonia and/or polyarthritis associated with M. bovis have been described associated with M. bovis have been described for many years in the veterinary literaturefor many years in the veterinary literaturefor many years in the veterinary literaturefor many years in the veterinary literatureAllen et al, 1978; Boothby et al, 1983; Adegboye Allen et al, 1978; Boothby et al, 1983; Adegboye et al, 1995; Adegboye et al, 1996; Haines et al, et al, 1995; Adegboye et al, 1996; Haines et al, g yg y2001.2001.Experimental infections with M. bovis Experimental infections with M. bovis demonstrate varying degrees of lungdemonstrate varying degrees of lungdemonstrate varying degrees of lung demonstrate varying degrees of lung involvementinvolvementIf M bovis given first Mannheimia experimentalIf M bovis given first Mannheimia experimentalIf M. bovis given first, Mannheimia experimental If M. bovis given first, Mannheimia experimental infections were much more severe in terms of infections were much more severe in terms of lung consolidationlung consolidation

CPPS: Sequence of EventsCPPS: Sequence of EventsCPPS: Sequence of EventsCPPS: Sequence of Events

Initially treated for high temperature Initially treated for high temperature eg. eg. >> 40.540.5ooCC

Temperature decreases but remain sick andTemperature decreases but remain sick andTemperature decreases but remain sick and Temperature decreases but remain sick and soresoreOver next 10 days joints enlargeOver next 10 days joints enlargeOver next 10 days joints enlargeOver next 10 days joints enlargeCalf retreated several timesCalf retreated several timesDoes not respond to therapyDoes not respond to therapy

CPPS: Sequence of EventsCPPS: Sequence of EventsCPPS: Sequence of EventsCPPS: Sequence of Events

Difficulty with getting up and lyingDifficulty with getting up and lyingDifficulty with getting up and lying Difficulty with getting up and lying becomes apparentbecomes apparentSevere, painful lamenessSevere, painful lamenessEmaciation hypothermia frostbiteEmaciation hypothermia frostbiteEmaciation, hypothermia, frostbite Emaciation, hypothermia, frostbite become complicationsbecome complications

CPPS: Working HypothesisCPPS: Working HypothesisCPPS: Working HypothesisCPPS: Working Hypothesis

Infection occurs via respiratory tract, therefore, Infection occurs via respiratory tract, therefore, Broncho PneumoniaBroncho PneumoniaAll cases have some pneumonia!All cases have some pneumonia!M. bovis invades blood stream and is distributed to M. bovis invades blood stream and is distributed to other parts of bodyother parts of bodyOrganism invades lungs, joints, tendon sheaths, and Organism invades lungs, joints, tendon sheaths, and pleural spacepleural space4040--50% of cases have arthritis!50% of cases have arthritis!Antibiotics cannot penetrate these lesions or are not Antibiotics cannot penetrate these lesions or are not effective against M. boviseffective against M. bovisggCharacteristic lesions lead to extreme “ill thrift”Characteristic lesions lead to extreme “ill thrift”

Why Is This Happening?Why Is This Happening?

M. bovis is a “Shape Shifter”M. bovis is a “Shape Shifter”M. bovis is a Shape ShifterM. bovis is a Shape ShifterIt has the ability to change it’s surface It has the ability to change it’s surface proteinsproteins“Switching mechanism”“Switching mechanism”Switching mechanismSwitching mechanismIt also mutates at a higher rate than It also mutates at a higher rate than other bacteriaother bacteriaMay be able to adapt to antibioticsMay be able to adapt to antibioticsMay be able to adapt to antibiotics May be able to adapt to antibiotics fasterfaster

CPPS: OutcomesCPPS: OutcomesCPPS: OutcomesCPPS: OutcomesSome completely recover with Some completely recover with patiencepatienceS i ll d bS i ll d bSome partially recover and can be Some partially recover and can be salvagedsalvagedS b li t dS b li t dSome become complicatedSome become complicated–– unable to get upunable to get up–– become very thinbecome very thin–– develop secondary syndromesdevelop secondary syndromes–– must be destroyed or inevitably must be destroyed or inevitably

diedie

Feedlot epidemiology of M bovisFeedlot epidemiology of M bovisFeedlot epidemiology of M. bovisFeedlot epidemiology of M. bovis

Of the 12,039 fall placed calves were Of the 12,039 fall placed calves were eligible for inclusion in study eligible for inclusion in study g yg y27.3% (3283) were treated at least once 27.3% (3283) were treated at least once for either UF or lameness i e are at riskfor either UF or lameness i e are at riskfor either UF or lameness, i.e., are at risk for either UF or lameness, i.e., are at risk of succumbing to chronic infectious of succumbing to chronic infectious diseasedisease4.8% (156) of calves at risk or 1.3% of the4.8% (156) of calves at risk or 1.3% of the4.8% (156) of calves at risk or 1.3% of the 4.8% (156) of calves at risk or 1.3% of the entire population entered the convalescent entire population entered the convalescent penpenpenpen

Proportional morbidity among calves in the Proportional morbidity among calves in the convalescent penconvalescent pen

0 600.50

0.420.50

0.60

0.30

0.40

0.20

0.05 0.030.00

0.10

UF tx: failure Arthritis tx:failure

Lame (not PA) Not examined

Mortality ratesMortality ratesMortality ratesMortality rates

40% (62/156) calves with chronic infectious 40% (62/156) calves with chronic infectious disease, died or were euthanized in the disease, died or were euthanized in the disease, died or were euthanized in the disease, died or were euthanized in the convalescent penconvalescent penIn contrast to the remainder of the fallIn contrast to the remainder of the fall--placed calfplaced calfIn contrast, to the remainder of the fallIn contrast, to the remainder of the fall--placed calf placed calf population where only 0.8% (96/11883) either population where only 0.8% (96/11883) either died or were euthanizeddied or were euthanizeddied or were euthanizeddied or were euthanizedAlthough calves with chronic infectious disease Although calves with chronic infectious disease made up only 1 3% (156/12039) of the entiremade up only 1 3% (156/12039) of the entiremade up only 1.3% (156/12039) of the entire made up only 1.3% (156/12039) of the entire population, they contributed 39% (62/158) of all population, they contributed 39% (62/158) of all the mortality among fall placed calvesthe mortality among fall placed calvesthe mortality among fall placed calvesthe mortality among fall placed calves

Relative risk of death for calves Relative risk of death for calves with CPPSwith CPPS

A calf that entered A calf that entered the convalescent the convalescent pen due to CPPS pen due to CPPS was 49 2 timeswas 49 2 timeswas 49.2 times was 49.2 times more likely to die more likely to die or be euthanizedor be euthanizedor be euthanizedor be euthanized

FDO for CPPS Hemophilosis & BRDFDO for CPPS Hemophilosis & BRDFDO for CPPS, Hemophilosis & BRDFDO for CPPS, Hemophilosis & BRD

25

15

20

of c

alv

CPPS

10

15

umbe

r o CPPSHemophilosisBRD

0

5Nu

01 2 3 4 5 6 7 8 9 10 11 12

Weeks on feed to first treatment or death

Mortality Curves forMortality Curves forCPPS, Hemophilosis & BRDCPPS, Hemophilosis & BRD

20

16

20

calv CPPS

8

12

mbe

r of c Hemophilosis

BRD

0

4Num

01 3 5 7 9 11 13 15 17

Weekson feed to deathWeeks on feed to death

BVD’s role in Bovine BVD’s role in Bovine Respiratory Disease Respiratory Disease

Synergistic effects between BVDV and Synergistic effects between BVDV and other respiratory pathogens have been other respiratory pathogens have been p y p gp y p gdocumenteddocumented

IBR Mannheimia hemolytica BRSVIBR Mannheimia hemolytica BRSV–– IBR, Mannheimia hemolytica, BRSVIBR, Mannheimia hemolytica, BRSVSeroconversion to BVDV has been Seroconversion to BVDV has been significantly associated with BRD (Martin significantly associated with BRD (Martin et al, O’Connor et al)et al, O’Connor et al), ), )High titres to BVD have been shown to be High titres to BVD have been shown to be protective for UF (Booker et al)protective for UF (Booker et al)protective for UF (Booker et al) protective for UF (Booker et al)

Primary BVD and Primary BVD and ImmunosuppressionImmunosuppression

Even though most primary BVD infections Even though most primary BVD infections are subclinical, many cause a transient are subclinical, many cause a transient , y, yimmunosuprressionimmunosuprressionPI animals may have a permanentlyPI animals may have a permanentlyPI animals may have a permanently PI animals may have a permanently impaired immune responseimpaired immune responseLymphocyte populations are diminished Lymphocyte populations are diminished reaching minimal numbers 5reaching minimal numbers 5--10 days after10 days afterreaching minimal numbers 5reaching minimal numbers 5 10 days after 10 days after infectioninfectionAl ff t f ti f th WBC’Al ff t f ti f th WBC’Also affects function of other WBC’s Also affects function of other WBC’s

BVD and Mycoplasma bovisBVD and Mycoplasma bovisBVD and Mycoplasma bovisBVD and Mycoplasma bovis

Haines et al demonstrated BVDV by IHC Haines et al demonstrated BVDV by IHC in 40% of cases of chronic respiratory in 40% of cases of chronic respiratory p yp ydisease +/disease +/-- arthritis (CPPS) (Can Vet J, arthritis (CPPS) (Can Vet J, 2001)2001)2001)2001)–– M. bovis demonstrated in 80% of 49 casesM. bovis demonstrated in 80% of 49 cases

% f % f% f % f–– 45% of joints, 71% of lungs45% of joints, 71% of lungs–– Only bacterial pathogen identified in jointsOnly bacterial pathogen identified in joints

BVD and Mycoplasma bovisBVD and Mycoplasma bovisBVD and Mycoplasma bovisBVD and Mycoplasma bovis

Shahriar et al found BVDV in 64% of 48 Shahriar et al found BVDV in 64% of 48 cases of retrospective cases of CPPS cases of retrospective cases of CPPS ppusing IHC(Can Vet J, 2002)using IHC(Can Vet J, 2002)Also demonstrated BVDV in 9/16Also demonstrated BVDV in 9/16Also demonstrated BVDV in 9/16 Also demonstrated BVDV in 9/16 prospective casesprospective casesM bovis was present in 44/48 and 15/16 M bovis was present in 44/48 and 15/16 cases respectivelycases respectivelycases respectivelycases respectively

Causes of mortality based on gross Causes of mortality based on gross necropsy in study group (n=277)necropsy in study group (n=277)

BVD7%

UNKNOWN7%

BRD17%

AIP4%

OTHER10%

4%

CPPS

HEMOPHILOSIS19%

CPPS28%DIGESTIVE

8%

Distribution of BVD + Samples Distribution of BVD + Samples ithi M t lit C t iithi M t lit C t iwithin Mortality Categories within Mortality Categories

(PI calves excluded)(PI calves excluded)(PI calves excluded)(PI calves excluded)

OTHER

UNKNOWN

HEMOPHILOSIS

BRD

CPPS

DIGESTIVE

BVD

AIP

0.0% 10.0% 20.0% 30.0% 40.0% 50.0%

Comparisons of BVDComparisons of BVDComparisons of BVD Comparisons of BVD prevalence in tissues of various prevalence in tissues of various

mortality categoriesmortality categories

BRD (33.3%) vs NonBRD (33.3%) vs Non--infectious (15.3%) infectious (15.3%) ( 0 03)( 0 03)(p=0.03)(p=0.03)BVD (44.4%) vs. NonBVD (44.4%) vs. Non--infectious (15.3%) infectious (15.3%) (p=0.04)(p=0.04)CPPS (37.0%) vs. NonCPPS (37.0%) vs. Non--infectious (15.3%) infectious (15.3%) ( )( ) ( )( )(p<0.01)(p<0.01)Hemophilosis (17.0%) vs. NonHemophilosis (17.0%) vs. Non--infectiousinfectiousHemophilosis (17.0%) vs. NonHemophilosis (17.0%) vs. Non infectious infectious (15.3%) (p=0.8)(15.3%) (p=0.8)

Treatment of CPPSTreatment of CPPSTreatment of CPPSTreatment of CPPSNo drugs labeled specifically for treatingNo drugs labeled specifically for treatingNo drugs labeled specifically for treating No drugs labeled specifically for treating mycoplasmasmycoplasmasTh i id th t tibi tiTh i id th t tibi tiThere is no evidence that antibiotic There is no evidence that antibiotic therapy is useful once the syndrome is therapy is useful once the syndrome is id tifi did tifi didentifiedidentified–– Many common antimicrobials have no activity Many common antimicrobials have no activity

against Mycoplasma spp. because of lack of against Mycoplasma spp. because of lack of cell wallcell wall

–– Many antimicrobials do not achieve Many antimicrobials do not achieve therapeutic concentrations in jointstherapeutic concentrations in joints

–– Extensive tissue damage may make disease Extensive tissue damage may make disease process irreversible in many casesprocess irreversible in many cases

Treatment of CPPSTreatment of CPPSTreatment of CPPSTreatment of CPPS

Nursing careNursing care–– Well bedded penWell bedded pen–– Easy access to feed Easy access to feed

and waterand water–– Less competitionLess competition

Appropriate Appropriate monitoring of chronic monitoring of chronic penpen

Animal Welfare IssuesAnimal Welfare IssuesAnimal Welfare IssuesAnimal Welfare Issues

Of the calves with lesions Of the calves with lesions of the CPPS at necropsy, of the CPPS at necropsy, 96% had been96% had been96% had been 96% had been euthanized for humane euthanized for humane reasons, because they reasons, because they , y, ywere either moribund, were either moribund, unable to rise or unable to rise or continually lost weight continually lost weight (Pollock et al)(Pollock et al)M it i l lfM it i l lfMonitor animal welfare Monitor animal welfare management and set management and set criteria for euthanasiacriteria for euthanasiacriteria for euthanasiacriteria for euthanasia

Control of CPPSControl of CPPSControl of CPPSControl of CPPST diti l t l f BRDT diti l t l f BRDTraditional control measures of BRD may Traditional control measures of BRD may aid in prevention of CPPSaid in prevention of CPPSE l t t t d ti f BRDE l t t t d ti f BRDEarly treatment and prevention of BRD Early treatment and prevention of BRD cases almost certainly reduces the cases almost certainly reduces the incidence of CPPSincidence of CPPSincidence of CPPSincidence of CPPSBiosecurity issues are importantBiosecurity issues are important

A i l ith h i i d bA i l ith h i i d b–– Animals with chronic pneumonia caused by Animals with chronic pneumonia caused by M. bovis may be very infectiousM. bovis may be very infectiousSeparate from other animalsSeparate from other animals–– Separate from other animalsSeparate from other animals

–– BVDV biosecurity in terms of minimizing the BVDV biosecurity in terms of minimizing the presence of PI’s may be of valuepresence of PI’s may be of valuepresence of PI s may be of valuepresence of PI s may be of value

Control of CPPSControl of CPPSControl of CPPSControl of CPPS

V i ti f M l b i h tV i ti f M l b i h tVaccination for Mycoplasma bovis has not Vaccination for Mycoplasma bovis has not been promising to datebeen promising to dateWill vaccination for BVDV on or before Will vaccination for BVDV on or before arrival spare CPPS incidence?arrival spare CPPS incidence?ppWill elimination of persistently infected Will elimination of persistently infected BVD calves from feedlot pens reduce theBVD calves from feedlot pens reduce theBVD calves from feedlot pens reduce the BVD calves from feedlot pens reduce the incidence of CPPS?incidence of CPPS?Will t h l ti f D iWill t h l ti f D iWill metaphylactic use of Draxxin on Will metaphylactic use of Draxxin on arrival reduce the incidence of CPPS?arrival reduce the incidence of CPPS?

SummarySummaryyy

M. bovis is a ubiquitous and persistent organism M. bovis is a ubiquitous and persistent organism in cattle populations in North Americain cattle populations in North AmericaCPPS seems to be an emerging syndrome in CPPS seems to be an emerging syndrome in Western Canadian feeding operations with Western Canadian feeding operations with ggsignificant economic consequencessignificant economic consequencesBVDV may play a synergistic role with M. bovisBVDV may play a synergistic role with M. bovisBVDV may play a synergistic role with M. bovis BVDV may play a synergistic role with M. bovis in causing respiratory diseasein causing respiratory diseaseTreatment and control options are at best limitedTreatment and control options are at best limitedTreatment and control options are at best limitedTreatment and control options are at best limited