The High Immune Response Technology:

A Scientific Journey from the Bench

to the Barn and Back Again!

Professor Bonnie MallardDepartment of PathobiologyOntario Veterinary School

Centre of Genetics Improvement of Livestock

University of GuelphGuelph, Ontario

Canada

AAPA 2014

Livestock Producers WantHealthier Animals!

SO WHAT’S THE PROBLEM?

� Disease difficult to improve genetically - low heritability

� Poor data quality & inconsistency in disease diagnosis and recording

� Selection to fight one disease may be counter-productive to other diseases (eg mastitis vs myobacteria)

� No direct measures of health in many selection indices,(mastitis in some dairy indices)

University of Guelph

� The field of Immunogenetics was just getting beginning in livestock.

� We began by determining heritability of

some simple IR traits in dairy cattle.

MSc. AdvisorProfessor

Ted Burnside

1960’s – 1980’s

Journal of Dairy ScienceVolume 66, Issue 4, April 1983, Pages 862–866

Research-Article

Variation in Serum Immunoglobulins in Canadian Hols tein-FriesiansB.A. Mallard 1, E.B. Burnside 1, J.H. Burton 1, B.N. Wilkie 2

First Publication Mallard et al., 1983

One of the first papers showing heritability of immune response traits in cattle.

h of bovine immunoglobin (Ig) ranged from 0.10 - 0.47 depending on the isotype and method of estimation.

2

Disease Occurrence was Rising in High Producing, Intensively

Raised Livestock

e.g. Dairy Disease Trends in USA

0

5

10

15

20

25

30

35

40

45

50

1996 2001 2007

Repro (Metritis)

Retained Placenta

Respiratory

Lameness

Mastitis

NAHMS Dairy 2007 Part II: Changes in the Dairy Cattle Industry 1991-2007

Need a Better Approach to Livestock Health Management

• A starting point for healthier animals.• Even better than direct selection for

health traits.

� Selection for Improved Immune Response

� Change the way producers will select for

health and manage their herds

Genetic Selection for Immune Response should Improve

Disease Management Interventions

� Via Improved Breeding and Culling Decisions

� Via Improved Vaccine Protocols

� Via Improved Colostrum Management

� Via Improved Hoof Health Information

Three Types of Immunityin Mammals

� Passive Immunity

� Innate Immunity

� Adaptive Immunity

Passive Immunity

� Initial and temporary

� Passed through colostrum

� Contains protective features from the dam

� Fades as own immune system matures

Innate Immunity

Innate

Immunity

Immune Response Genotype

First line of defense against harmful invading microbes

� Non-specific responses� No memory of past exposure to pathogen� Not long-lasting� Initiation of IR

Adaptive Immunity

Innate

Immunity

Immune Response Genotype

� Primed by the Innate component

� Recognizes broad range of microbes & remembers them on subsequent exposure - responses become more

more rapid & stronger

� Specific and long-lasting

EPIGENOME

Adaptive Immunity -Two Branches

Innate

Immunity

Immune Response Genotype

~2000 Genes

Immune Response Genotype

~2000 Genes

Overall Resistance to Diseases

CMIR- Fights intracellular infections

ex. Virus or

mycobacterium

(Johne s Disease)

AMIR- Fights extracellular infections

ex. bacteria

(Mastitis)

Reference: Wilkie, B. and Mallard, B. Vet Immunol Immunopath 72:231-235

Defense Against DiseaseOverall broad -based defense against most

diverse pathogens

Selecting for improved immune responseis the concept behind the

High Immune Response Technology

Mallard et al. 1998. Proc. WCGALP 27:257

Immune Response

Traits

Antibody to Test Antigen (HEWL)

Delayed-type hypersensitivity

(PPD)

Lymphocyte Proliferation

(ConA)

Serum Immunoglobulin

(IgG)

Yorkshire Pigs Selected for High & Low Immune

Responses based on EBVs

CONTROL

-1.5

-1

-0.5

0

0.5

1

1.5

0 1 2 3 4 5 6 7 8

GENERATION

EB

Vs HIGH

LOW

University of Guelph1980’s – 1990’s

Combined (AMIR + CMIR) EBVs of Pigs RankedWithin High, Control & Low Immune Response Lines

Wilkie and Mallard. 1999. Selection for High Immune Response. Vet Immunol Immunopath 72(1-2):231

ANTIBODY RESPONSE toA. pleuropneumoniae Bacterin in G4 Pigs

Selected for High and Low IR

0

0.1

0.2

0.3

0.4

0.5

0.6

day 0 day 14 day 21

HighControlLow

Log

of O

D @

1/80

0dil’

n of

ser

a

NON RESPONDERS

High = 4%

Low = 19%

Control = 22%

a

a

bbb

c

Wilkie and Mallard. 1999. Adv. Vet. Med. 41:39

Mycoplasma hyorhinis-induced Lesions in G4 Pigs Selected for High and Low IR

0

0,2

0,4

0,6

0,8

1

1,2

1,4

Peritonitis Pleuritis Pericarditis Arthritis

HIGH

LOW

1

1

1

1

1

2

2

2

Lesion Score

Reddy, J. et al. 2000. Infection and Immunity 68(3):1150

0 1 2 3 4 5 6 7

HIGH

CONTROL

LOW

140

145

150

155

160

165

170

175

180

DAYS

GENERATION

HIGH

CONTROL

LOW

Average Days to 100 Kg Of Pigs SelectedFor High & Low Immune Responses

Wilkie and Mallard. 1999. Vet Immunol Immunopath 72(1-2):231

Immune Response Testing Procedures modified for use in Dairy Cattle

University of Guelph1990’s – 2000’s

ANTIBODY-MEDIATED IMMUNE

RESPONSE

CELL-MEDIATED IMMUNE RESPONSE

Photos and figures courtesy of Dr. B. Mallard

Two Tests are Performed toCapture Broad-based Disease Resistance

Studies in number of species show IR is highly heri table therefore will respond to selection

Immune Response

HIR Test Protocol

DAY 14

1. AMIR: Collect final blood for ELISA

2. Boost CMIR, take initial skin-fold measurements & skin-injection

DAY 15

1. CMlR: Take final skin-fold measurement at 24 hours

DAY 1

1. AMIR: Collect initial blood for ELISA

2. Immunize intramuscularly with HIR test agents

HIR test is a 15 day test that requires 3 farm visits:The HIR test requires 3 farm visits:

Individuals with a robust and balanced IRare called High Immune Responders and themethod is identified as the HIR Technology

Done Once per Lifetime

High Immune Response (HIR) Technologyis emerging as a Genetic and Management Tool that:

� Identifies cattle with a greater ability to resist a variety of diseases including mastitis

� Done once in an animal’s lifetime

� Can be done as early as 2 months of age

� Is heritable (h2=0.25) & cattle can pass on their disease resistance ability to offspring

� Is very accurate based on a 95% CI

University of Guelph2005 - 2014

1 STD above the Population Meanfor Immune Response

(ie Top 16-20% of cows for AMIR + CMIR)

Low Responders High Responders

Immune Response Classification

What’s The Significance of beinga High Immune Responder?

Overall Lower Disease Incidence

Disease incidence

(average for all

diseases) for each

immune response

category.

About half the disease

in H vs L Responders

n = 64 herds HIGH

16%

14%

12%

10%

8%

6%

4%

2%

0%

AVERAGE LOW

Ref - Mallard et al., Advances in Dairy Technology 26:247, 2014

Less Disease

Ref - Thompson-Crispi, Mallard et al ., JDS 95(7):3888, 2012

High Immune Responders have Less Disease

Range in all herds was 19–30% less incidence of disease

(High responders vs. herd average)

27% 17% 32%Mastitis Metritis Retained Placenta

700 cows in 3,000

cow dairy in

North Florida

High Antibody Responders

17%

Low Antibody Responders

31%

Lower Mastitis IncidenceIncidence Rate of Clinical Mastitis in Cows Across Canada

Ref - Thompson-Crispi and Mallard, et al Clin Vaccine Immunol, 2012

Average Antibody Responders

28%

P.J. Pinedo, A. Donovan, O. Rae and De la Paz, Proc. Int. Colloq. Paratb., Mn, Aug 9-14, 2009

Categories :

Negative (OD=0- 0.49)

Inconclusive (OD 0.5-0.99)

Positive (OD 1.0-3.49)

Strong Positive (OD>3.5)

0

5

10

15

20

25

30

35

High Average

Pro

port

ion

of s

erop

ositi

ve lo

w c

ows

High CMIR = Less Johne’s Seropositive Cows

Improved Vaccine Response

HIR cows

respond better

to commercial

vaccines

Ref - Wagter & Mallard et al JDS 83:488, 2000

0

0.2

0.4

0.6

0.8

1

1.2

Wk -8 Wk -3 Wk 0 Wk +3 Wk +6

High

Average

Low

(eg. J5 E. coli vaccination)

Better Quality Colostrum

� Specific antibody

ALSO:

• Total IgG

• B-Lactoglobulin

Ref - Wagter & Mallard et al JDS 83:488, 2000;

Fleming MSc Thesis, 2014

WK 0 WK 2 WK 3 WK 4 WK 6

3

2.5

2

1.5

1

0.5

0OD

ELISA

High

Average

Low

Lameness - Leading Cause of Culling

� High AMIR cows had

less Infectious Digital

Dermatitis, but more Non-

Infectious Hoof Lesions

� High CMIR cows tended

to have less Interdigital

hyperplasia

Recent data from - Cartwright, Thompson-Crispi,

Paibomesai , Miglior and Mallard

Infectious Digital Dermatitis

H-AMIR

A-AMIR

L-AMIR

High23%

Low 50%

Ave 60%

N=190

Economic Value of High Response Cows

Mastitis, metritis, retained placenta, milk fever, Johne’s, pneumonia...

Lower incidence of disease

Improved vaccine response

Higher quality colostrum

Lower cull rates

Additional $124 or more per cow per year

Breeding Benefits – Semex’s Approach

� Test all marketable

proven bulls & the

latest genomic bulls

� 929 HO, 133 JE, 57 AY bulls tested - all Semex

bulls are tested each year

� Top 10% for overall immune response

qualify for Immunity+

University of Guelph2013 License

No adverse reactions or CFIA cross-reactivity were found before and after HIR testing.

Sample of Test Results

Bulls Designated as Immunity+Approximately 10% of sires

Disease Occurrence of Immunity+ Daughters in a Large US Herd Milking 1500 Cows in 2013

(Data Courtesy of Jay Shannon, Semex Alliance)

Disease CattleImmunity+ Daughters

All Other Daughters

Disease Reduction

Mastitis1st lactation 8.8% 15.8% 44.3%

All Recorded Disease 1st lactation 16.7% 18.2% 8.5%

PneumoniaHeifers 6.8% 9.1% 25.3%

Disease reduction calculated as: (Disease incidence in all other daughters - disease incidence Immunity+ daughters) / Disease incidence in all other daughters * 100%

Sire Proof Data (August 2013) from Immunity+Sires Compared to all other Sires Tested for Immune Response using the HIR Method

Trait of Interest

Average Proof for

Immunity+ Sires

Difference between Immunity+ &

all other Sires Tested

TPI + 2305 +186 Favorable

Net Merit +$708 +$165 Favorable

Productive Life +4.7 +1.6 Favorable

Daughter Preg Rate +0.8 +0.70 Favorable

Somatic Cell Score 2.69 -0.11 Favorable

Daughter Calving Ease 5.7 -0.70 Favorable

(Data Courtesy of Jay Shannon, Semex Alliance)

Current Research & Development

� Validation of health results in daughters of HIR bulls

� Genomic studies on HIR

HIR Genomics Study

Objective: To determine genetic profiles associated with enhanced IR

Expt 1 Cows - Methods:• Selective genotyping of 680 cows • then from that population selected(AMIR - 81 HIR and 82 LIR)(CMIR – 75 HIR and 65 LIR)

Genomic Markers for Cow AMIR

Thompson-Crispi and Mallard et al . 2014.BMC Genomics 15:559

186 SNPs were Significant

p<0.001

p<0.05

Genomics of Immune Response

� Initial studies confirms that HIR measurements are hitting the right target

� Chromosome 23 contains the Bovine Major Histocompatibility Complex (BoLA) which is a gene cluster responsible for regulating immunity in cattle

� Antigen processing and presentation are important pathways in HIR/Immunity+

� Can lead to HIR genomics in future

SummaryGenetic Selection for

Immune Response should improve efficiency of disease management

Via Improved Breeding & Culling Decisions

Via Improved Vaccine Protocols

Via Improved Colostrum Management

Via Improved Hoof Health Information

Questions