Bovine RespiratoryDisease Complex andDesigning Effective
Vaccination ProgramsChris Chase
Department of Veterinary &Biomedical Sciences
South Dakota State UniversityBrookings, SD 57007
On The Road to ControlRespiratory Disease
• What is BRDC• Multi-factorial Diseases• Management of BRDC• BRDC Vaccine
Credits
• Immunobiology, 6th edition• David Topham, University of
Rochester• Dr. Chris Schneider, University of
Idaho• Dr. Nichols, Australia
Bovine Respiratory Disease Complex(BRDC)
• Single most significant infectious disease in cattle• Multifactorial
– Stress– Viruses– Bacteria
• All of these pathogens are in the normal bovine population• Incidence in the first 40 days on feed
– 10 – 30 days peak challenge• Up to 90% of morbidity• Up to 70% of mortality
BRDC
• Bronchopneumonia– Most common cause of dairy calf
mortality– Greater economic losses than any
other disease in feedlot calves• Dairy calves- enzootic pneumonia• Beef calves- shipping fever
BRDC
• Major challenge to cattle industry• 31% of cattle/calf death in US• $625 M impact/year• Feedlot Industry
– 65-79% of sickness– 44-72% of death
Bovine Respiratory DiseaseComplex
• Cost of BRD– Mortality– Morbidity
• Hospitalization• Medication costs• Increasing
feeding time• Labor costs
– Subclinical• Reduction of ADG
and FCR
Other Contributing Factors• Breed - Bos taurus vs bos indicus• Origin - saleyard vs direct off property ,
northern vs southern States• Age• Immune status• Temperament
Disease Triangle
Bovine Respiratory Diseaseis Multifactorial
Stress
TransportMixingDehydrationLack of feed
ProcessingHandlingMixingDustHeatColdWaterFeedCompetition
Viruses
IBRBVDVBRSVBRCV?PI3Adenovirus
Bacteria
M. haemolyticaP. multocidaH. somnusM. bovis
BRD
Stress• Stress is anything that reduces immune response
capability• Adaptation to intensive production is stressful
– Anything that improves adaptation will reduce costs and improveproduction
• The reason that this condition is seen more in intensiveoperation rather than extensive
Stress – Prior to Entry• Weaning• Saleyards• Co-mingling or mixing• Transport• Dehydration• Time off feed• Injury
Stressors at the Feedlot
• Co-mingling• Injury• Water - palability
and supply• Feed - time to
first• Pen density• Pen total number
• Handling andmovements
• Pen “add-ons”• Weather
extremes• Dust• COMPETITION
Morbidity Percent by Origin – Major Feedlots (2002).
6 - 10%Custom Fed
13 - 16%Private Purchase
20 - 25%Auction
Treatment PercentCattle Origin
Effect of Co-mingling
Pathogens Stressors
Viruses Mycoplasma Bacteria
Uncomplicatedrespiratory Disease
Damage
Bacterial pneumonia
Physical Environmental
Immune System
Psychological
X
Stress will decrease chemotaxis
Inflammatory Response
Neutrophil Chemotaxis and Phagocytosis
What Does Stress Do to Neutrophil Motility and Phagocytosis?
What Does MLV BVDV Do to Neutrophil Motility andPhagocytosis?
Bovine RespiratoryDisease(BRD)
• Viruses– IBR– BVDV– BRSV– PI3– Bovine
Coronavirus(BCV)
• Bacteria– Mannheimia
haemolytica– Pasteurella
multocida– Histophilus
somnus– Mycoplasma
bovis– Plus others
Sources of Pathogens
• Reactivation of “normal flora”• “Swap” pathogens• Mechanical
Respiratory Pathogens
• Bacterial agents normally inhabitURT-Normally there– Mannheimia haemolytica– Pasteurella multocida– Mycoplasma bovis
• Begin growing with stress &immunosuppression
Respiratory “Swap” Pathogens
• Aerosol, secretions, excretions– Trucks– Sales barns– Hospital pens
Respiratory Pathogens
• Mechanical transmission- needbiosecurity and disinfection– Handling facilities– Hospital crew
• Pathogens– Viruses
Bovine Viral Diseases
BRCVBRCV
BVD- Not a pathogen oflung- immunosuppressive
• For the last 15years at theSDSU DiagnosticLab, NCP BVDVhas been themajor isolate(>50% of all viralrespiratoryisolates).
• Type 2 vs Type 1
• Isolated from nasal swabs ofcalves
• Increasing importance?
Bovine RespiratoryCoronavirus
Bacterial Agents
• Mannheimia hemolytica A1– Most common isolate of fatal BRD cases
• Pasturella multocida– Affects younger cattle– Slow developing
• Histophilus somnus– Geographic significance-Northern Part of
North America
Mycoplasma bovis
• Arthritis• Chronic pneumonia• Otitis media
– Dairy calves primarily• Skin abscesses
Mycoplasma bovis
• Concern of stocker, feedlots, andreplacement heifers on the dairy
• Primary issue in stockers• Major problem since 1999• Vaccination efficacy poor• Outbreak Bison??
Strategies to decreaseincidence of BRD
• Aim to– Decrease mortality– Decrease morbidity
• Decrease treatment costs• Subclinical cost
– Improve performance• ADG• FCR
Prevention of BRDC
• Management– Eliminate stress factors where possible
– Recognize the “Critical Period” for diseasedetection (3 weeks that follow weaning;placing on feed; shipping of cattle)
Prevention of BRDC
• Management– Avoid co-mingling cattle from different
sources during critical 3-week period
– Keep new cattle close to feed and water
– Don’t over crowd (especially early in feedingperiod)
– Control dust and mud
Summary
• Environmental factors• Reducing group size is desirable• Ventilation and dust control are important• Transport time, rest, food water• Commingling should be avoided• Weaning before shipping decreases stress• Gradual feed changes with proper supplements are
beneficial
Diet and Immunity
• Immune system doesn’t get a freeride- energy consumer- calves on poornutrition- poor response to vaccines• Multiple demands on energy for the calf-overvaccination can effect growth anddevelopment• Calves-Vaccinating prior to acclimationto feed (weaning; feedyard) Acidosis, poorvaccine response
EnergyAvailable
Maintenance
Growth & LeanDeposition
Young Calf
Immune response
Nutrition & ImmunologyOrder of importance of nutrients toimmune system
• Energy• Protein• vitamin A• vitamin E• Copper, Zinc, Selenium• IRON
Summary
• Acidosis affects memory• Energy is important for immune response• Vitamin A deficiency can decrease mucosal
homing• Zinc is very important at times of stress• Vitamin E/Selenium important for many
immune responses
Harvey Dunn (1884-1952) Prairie is My Garden, South DakotaArt Museum
Prevention of BRDC
• Management
• Vaccines
Intranasal Vaccines
• Nasalgen– Day old calves
• Onset– Conducted in young calves (3-8 days of age)– Challenged with virulent strains of IBRV, BVD 1,
BVD 2, BRSV, PI3, Pasteurella multocida – 21to 28 days post-vaccination
• Enforce -3 BRSV Nasal studies 14 day oldcalves
Respiratory Immmunlogy
Respiratory Immunology
• Mucosal Immune Response is the mostimportant defense system
• Almost all bovine pathogens enter via theairways and the mucosa surface
• Viruses- BHV-1, BVDV, PI3, BRSV, BRCV• Bacteria- M. haemolytica, P. multicida, H.
somnus, M. bovis
Mucosal Immunity - Local response
YYYYU
YYYYU
Mucosal Immunity - Local response
YYYYUYY YYU
YY YYUYYYY
U YYYYUYY YYU
YY YYU
YY YYU
YYYYU
Stop them before they infect
When Do We BeginVaccinating Calves?
• At a week of age• At a month of age• At 2-3 months of age• Before they are born by
vaccinating the cow-High qualitycolostrum
What RespiratoryInfectious Agents are
Important• Calves
– 3 weeks- 3-4 months• Pasteurella multicida• Mannheimia (Pasteurella) hemolyticae-herd history• Clostridial diseases• BRSV- herd history, summer pneumonia• Leptosporosis• Mycoplasma bovis (pneumonia, inner ear)??• BVDV???
What Respiratory InfectiousAgents are Important
• Calves– 3-4 months- 12 months
• Brucella abortus*• Pasteurella multicida• Mannheimia (Pasteurella) hemolyticae• Leptospirosis• Clostridial diseases• Mycoplasma bovis-arthritis• BVDV• BRSV• PI3• IBR
Beef Vaccination Schedules• Calves (<4 months)
• Respiratory Diseases• MLV
– Calves on Vaccinated Cows-MLV Intranasal vaccines– Depends on Maternal Antibody levels-MANY MLV IM or
SC NOT EFFECTIVE-ONLY adjuvanted MLV IM or SC)• Inactivated- Well adjuvanted, not affected by Maternal
Antibody• NOT Vaccinate with MLV BVDV before 1 month
Better after 2-3 months of age
Beef Vaccination Schedules• Calves (>4 months)
– Respiratory Diseases• 2-3 weeks prior weaning
– MLV-1 dose– Inactivated-2 doses
• At weaning- avoid– MLV-Immunosuppressive– Inactivated-2 doses
• 2-3 weeks post weaning– MLV-1 dose– Inactivated-2 doses
Stress +Immunosuppressive Viruses=Super Immunosuppresssion
IBR and BVDV MLV are immunosuppressive
Timing of Boosters
Timing and the Adaptive Immune Response-Anamnestic Response
Lymphocyteapoptosis
Lymphocyteproliferationto Ag A
1° responseto antigen A
A A4 16128 20 64 68 72
Magnitudeof specificresponse
Days
2° responseto antigen A
What is the Best Time Interval for Boostering?
Timing and Immune Response- Young AnimalsPrimary vs Booster Response
A A
147 21 28 35
Per
cent
Sus
pect
ible
Days Post VaccinationA
00
50
100Active Immunity
Window ofSusceptibility
Passive Immunity
70%
21%
Booster Time Interval and Response451 CalvesBranding time 67 days3 weeks prior to weaning 167 daysWeaning 190 days
Group 1 vacc 67d and 190d ~120d intervalGroup 2 167d and 190d ~25d intervalo % seroconverted to each virus was sameo No difference in morbidity and mortality, feedlot performance or carcass qualityKirkpatrick et al. 2008 JAVMA 233:136-142
Timing of Boosters
• MLV 2-3 doses by time 8-10months
• Inactivated 2-3 doses by time 8-10months
Boostering MLV vs Inactivated-
• Evidence in either sequenceMLV/Inactivated orInactivated/MLV results insimilar responses
Grooms et al 2002; Royan 2009
Use them in combination-Better adjuvants
Vaccine efficacyRemember BRD is
MultifactorialStress
TransportMixingDehydrationLack of feed
ProcessingHandlingMixingDustHeatColdWaterFeedCompetition
Viruses
IBRBVDVBRSVPI3Adenovirus
Bacteria
M. haemolyticaP. multocidaH. SomnusM. bovis
BRD
Summary
• Vaccination of dams 4-6 weeks prior to calvingimproves colostral antibodies
• Passive antibodies (colostrum) are protective• Vaccinate before shipping• Vaccinate at least a few days after shipping- a
week or two later is best
Summary
• In general we vaccinate calves too much andtoo soon
• No need to vaccinate for BVD before 2-3months of age (don’t do it before 1 month)
• Better colostrum management, less need tovaccinate
• Intranasal vaccines in young calf especially forBRSV important- if BRSV is a problem
Summary
• Interval for boosting needs to bemore 21 days- length depends onvaccine
• Too short a vaccination intervalcan cause problems