A presentation about Fowl Adenovirus in chickens. It provides insights on: etiology, pathology, monitoring and control among others. Presented globally on September 9th 2014 via Watt Ag-Net Webinar by Dr. Rafael Monleon Contact me in LinkedIn for any question: www.linkedin.com/rafaelmonleon

1. Fowl Adenovirus:
Using Serology to Control
Your Flocks
Rafael Monleon DVM, MSpVM, ACPV, PAS
Business Unit Manager (Poultry)
9th September 2014

2. Adenovirus
• Double stranded DNA; Non-enveloped
• Reproduce in nucleus
• Produce intranuclear inclusion bodies

3. Adenovirus
•Very resistant
•pH changes
•Disinfectants
•60-70C for 30 minutes
•Formaldehyde and some other disinfectants
have been somehow effective

4. Adenovirus
•Worldwide distribution
•Ubiquitous in poultry farms
•Chicken
•Turkeys,
•Ducks, geese, quail
•Found also in wild birds

5. Familiy Adenoviridae
• Genus Aviadenovirus: Group I Avian Adenoviruses
• Fowl Adenovirus - 12 Serotypes / 5 Species
• Inclusion Body Hepatitis (IBH)
• Hydropericardium Syndrome (Angara Disease)
• Gizzard Erosion and Proventiculitis
• Genus Siadenovirus: Group II Avian Adenoviruses
• Hemorraghic Enterititis (turkeys), Marble Spleen Disease
(pheasants), Splenomegaly (chickens)
• Genus Atadenovirus: Group III Avian Adenoviruses
• Egg Drop Syndrome (EDS)

6. Classification FAV
Family
Adenoviridae
Genus
Aviadenovirus
AD Group I
A
B
C
D
E
FAV-1
FAV-5
FAV-11
FAV-8b
FAV-2
FAV-3
FAV-9
FAV-4
FAV-10
FAV-6
FAV-7
FAV-8a
CELO, 112, QBV, Ote, H1
340, TR22, M2, Tipton, IBH-2A
KR5, 506, H2, K31, 61, J2-A
C2B, M11, CFA20, SA2, C-2B
SR48, 685, H3, P7-A, GA1-1, Z7
SR49, 75, H5, 75-1A-1
A02, 90, CFA19, A2-A
CR119, 168
UF71, 380
YR36, X11, X11-A, 122
TR59, 58, CFA40, T8-A
764, VRI-33, B-3A
ICTV Classification

7. Fowl Adenovirus (FAV)
Epidemiology
• Antibodies to FAV can be found in many
poultry flocks
• FAV can be isolated from healthy as well as
clinical birds
• Vertical transmission important in spread or
“seeding” farms with several serotypes

8. • Birds can be infected with more than one
serotype
• Protection is primarily serotype specific
• Some Cross-protection Between Serotypes
•3&4 / 2&11
• Birds can shed a serotype while having
antibodies to another serotype
Fowl Adenovirus (FAV)
Epidemiology

9. Fowl Adenovirus (FAV)
Transmission
• Horizontal Transmission
• Usually >15-20d
• Litter, Equipment, Personnel
• Recurrent Problem in Poorly C+D Houses
• Commonly related with immunosuppression

10. Fowl Adenovirus (FAV)
Transmission
• Vertical Transmission
• Approx. >3d – 18-20d
• Breeders not seroconverted before lay
• Infection During Lay > Virus shedding for 4-8 weeks
• When ALL breeders seroconvert shedding stops –
Vertical transmission stops
• Reactivation of latent virus might occur with stress
• “Clean House Syndrome”
• Generally Seen High Levels Biosecurity
• “Dirty” Houses – Re-used litter – Less Problems

11. Dynamics of FAV Infection
Scenario I
16 W 40 W25 W8 W
FAV
Infection
Point of
Lay
NO TRANSMISSION OF ACTIVE
VIRUS TO PROGENY
%
Positives
(seroconversion)
VERY IMPORTANT TO ACHIEVE
SEROCONVERSION BEFORE LAY

12. Dynamics of FAV Infection
Scenario II
12
16 W 40 W25 W
%
Positives
(seroconversion)
8 W
FAV
Infection
Point of
Lay
TRANSMISSION OF ACTIVE
VIRUS TO PROGENY FOR A
PERIOD OF ~4 – 8 WEEKS
LOSSES DUE TO LATE SEROCONVERSION

13. FAV - VERTICAL TRANSMISSION
Offspring Mortality
AGE

14. FAV
Offspring Mortality – Vertical Transmission
FARM Dead
% Cum.
Mort.
Age of
Disease
B9 705 11.73% 0-6 -2-1wk.
A7 1,155 16.02% 0-6 -2-0 wk.
A8 1,769 24.83% 0-4-1-6 wk.
A2 83 1.43% 0-4-1-1 wk.
A3 291 4.98% 0-4-2-1 wk.
A4 535 9.22% 1-0-2-0 wk.
A5 510 8.56% 0-6-2-0 wk.
Total 5,048
Average
10.97%

15. Fowl Adenovirus (FAV)
Inclusion Body Hepatitis
• First Described in 1960’s in USA
• “the 3 days disease”
• 3d ↑ mortality, 3d plateau, and 3d drop in mortality
• Depression, Weakness, Jaundice, Convulsions, Anorexia, Death
• Enlarged, dystrophic friable liver with redish-yellowish color
• Pale necrotic pancreas, muscle hemorrhages, bursal atrophy
• Breeder Mortality, Drops in Egg Production & Hatchability Reported

16. Fowl Adenovirus (FAV)
Inclusion Body Hepatitis
• Multiple serotypes involved
• Serotype 2, 8b, 9, 11 common
• Traditionally Associated with IBD/CAV (ImS)
• Now Considered Primary As Well

17. Mortality
Associated
with FAV
(21D)
Dias Mortalidad
1 3
2 5
3 6
4 2
5 5
6 335
7 63
8 26
9 18
10 18
11 12
12 10
13 14
14 16
15 12
16 14
17 7
18 10
19 14
20 10
21 19
Cumulative Mortality
5.79%

18. Caribe @ 21D

19. India – Mortality >10%
INDIA
CUMULATIVE
MORTALITY
>10%

20. Fowl Adenovirus (FAV)
Hepatitis-Hydropericardium Syndrome
•
•
• Mainly Serotype 4 (FAV-4 / Species C)
• Broilers / Breeders
• Increase of pericardial fluid (hydropericardium); hepatitis
• Generally 3 weeks or older
• Variable mortality but can be very high 40%+
• Sometimes associated with Immunosuppression

21. Fowl Adenovirus (FAV)
Gizzard Erosion and Ulceration (GEU)
• Excessive erosion and ulceration of gizzard lining
• Mostly Species A (FAV-1) – Also reported FAV-8
• GEU experimentally reproduced
• Low mortality, uneven growth, increased FCR
• Also seen pancreatitis, proventiculitis, Hepatitis
• Rule-outs / Comorbidity: Mycotoxins, Biogenic Amines (Histamine,
Gizzerosine, etc.), Vitamine B6 deficiency

22. Fowl Adenovirus (FAV)
Gizzard Erosion and Ulceration (GEU)
Schade, 2013

23. Fowl Adenovirus (FAV)
Diagnostic Tools
• Histopathology – Gold Standard
• Intranuclear Inclusion Bodies
• liver, pancreas, proventiculus or gizzard

24. Fowl Adenovirus (FAV)
Diagnostic Tools
• Virus Isolation / PCR / In-Situ Hybridization
• VI+PCR > Detecting Presence of Virus
• Sequencing > Determine Serotype /Species
• HRM (Alternative)
• PCR+ / VI+ Does not Equal Disease

25. Fowl Adenovirus (FAV)
Diagnostic Tools
• Serology
• VN - serotype specific antibody detection
• Serotype specific
• Tedious, expensive, complicated, few places to perform
• ELISA – group specific antibody detection
• Fowl adenovirus specific (Avian Adenovirus Group I)
• CANNOT DIFFERENCIATE BETWEEN SEROTYPES
• Easy to reproduce, inexpensive, automation, mass testing
• Interpretation of ELISA meaningful when comparing healthy vs.
clinical birds and/or having meaningful baseline / guidelines
• Baselines / Guidelines

26. • Launched in 2011
• Worldwide distributed FAV ELISA kit
• Fowl Adenovirus Serotype 1
• Indirect ELISA, dilution 1:100
• Specificity > 98 %
• Filter 405 nm
• Positive Cuttof S/P ≥ 0.5
• Positive Titer >1070
Biochek FAV ELISA

27. Detects Different Species
S/P RATIO Positive Cut-off >0.5
Biochek, Unpublished
0
1
2
3
4
5
6
7
FAV A FAV B FAV D FAV E FAV E
S/P

28. AGP vs. Histopathology vs. ELISA
ELISA Positive Titer 1070
BioChek, Unpublished
AGE (Days) AGP Histopathology ELISA
45 NEG 20/20 NEG 391
44 NEG 10/10 POS 13764
40 POS 3/18 POS 10401
46 POS 2/6 POS 10776
42 NEG 16/16 NEG 1087
42 NEG 16/16 NEG 624
41 NEG 16/16 NEG 969

29. FAV ELISA SPECIFICITY
POSITIVE CUT-OFF >0.5 (n=102) SPF
0
0.1
0.2
0.3
0.4
0.5
0.6
0 20 40 60 80 100 120
100% SPECIFICITY
BioChek, Unpublished

30. BioChek FAV
Breeders
 Birds in production generally positive
 Although poor seroconversion often occur
 Monitoring is useful to confirm seroconversion,
before entering production in troublesome areas
 BB should be 100% positive > 12-18W
 High antibody titers do not necessarily correlate
with protection
 Protection is SEROTYPE specific

31. BB 26 wks
Poor Seroconversion
AMT = 15200, CV % 53 AMT = 23467, CV % 20
BB 18 wks
Good Seroconversion
FAV ELISA

32. 0
5
10
15
20
25
30
35
40
0
5000
10000
15000
20000
25000
30000
Flock A Flock B
AMT
CV
FAV ELISA
MONITORING SEROCONVERSION BREEDER FLOCKS
POOR
SEROCONVERSION
GOOD
SEROCONVERSION
FLOCK AT RISK
OF INFECTION

33. BB 17W
BB 10W
BB 29WBB 29W
POOR SEROCONVERSION GOOD SEROCONVERSION

34. FAV ELISA
Challenged BB Flocks (Vertical Transmission)
512 512
4096
8192
32768
16384
0
5000
10000
15000
20000
25000
30000
35000
1 2 3
25 wks
29 wks
Adapted Grafl et. al, 2012Titers converted from log2
WEAK SEROCONVERTION
PRE-LAY
WITH SUBSEQUENT
INFECTION AND VERTICAL
TRANSMISSION

35. 0w 4w 9w 15w 26w
AMT 7730 365 12587 25451 29867
CV 86 119 39 21 12
0
20
40
60
80
100
120
140
0
5000
10000
15000
20000
25000
30000
35000
AMT
CV
FAV ELISA
Vaccinated @ 8 weeks
VACCINATION

36. FAV ELISA
BB 12w old / Vaccinated @ 8 weeks
23143
22098
23993
22398 22422
0
10
20
30
40
50
60
70
80
90
100
0
5000
10000
15000
20000
25000
30000
A B C D E
AMT
CV
Flock

37. FAV ELISA
BB Flocks / Vaccinated @ 12-13wks
0
10
20
30
40
50
60
70
80
90
100
0
2000
4000
6000
8000
10000
12000
14000
16000
18000
20000
25w 60w
AMT
CV
Flock A Flock B
LOW AMT / HIGH CV
SEROTYPE?/PRIMING?

38. BioChek FAV
Day Old Chicks
• Biochek FAV ELISA can demonstrate antibodies in DOC
• Samples in group 0 (negative) can be easily infected
• Positive titers do not necessarily correlate with protection
• Protection is SEROTYPE specific – Not GROUP specific
• Some examples of serology of DOC field data
• DOC offspring from vaccinated breeders
• FAV Serotype 4 – Inactivated Vaccine x1/x2

39. FAV ELISA
Monitoring MAB DOC
10/20 NEGATIVE
DOC AT RISK

40. BioChek FAV
Broilers
• Limited data available
• Many healthy broiler flocks will test low
positive (MT < 5000) at > 35D
• Clinical flocks have MT > 6500
• Useful to compare healthy non-clinical birds
with clinically affected birds
• Baselines

41. FAV ELISA
Naturally Infected Broilers 45D-46D
0
10
20
30
40
50
60
70
80
90
100
0
2000
4000
6000
8000
10000
12000
14000
16000
18000
20000
A B C D
(%)
Titer
FLOCK
AMT
CV
NON-CLINICAL

42. IBH Broilers
Case History
 First symptoms at 13-16D
 Depressed, crouching position, lethargic with acute mortality
 Peak mortality 3-5D after first symptoms, disappearing after
6-7D.
 Total mortality at slaughter between 8 – 30%
 Enlarged, dystrophic liver with yellowish color and crumbly
texture
 Nephritis
 Intracellular Inclusion bodies in liver and kidney tissues
CESAC, SPAIN

43. CESAC, SPAIN

44. FAV ELISA
Non-clinical vs. Clinically Affected Flocks
0
10
20
30
40
50
60
70
80
90
100
0
2000
4000
6000
8000
10000
12000
14000
16000
Non-Clinical Clinically Affected
AMT
CV
CESAC, SPAIN

45. FAV ELISA
Clinically Affected Broiler Flock Over Time
0
20
40
60
80
100
120
140
0
2000
4000
6000
8000
10000
12000
14000
16000
16d 38d
AMT
CV
START CLINICAL
SYMPTOMS
SLAUGHTER

46. Control of Disease
• Prevent Immunosuppression
• IBD, CAV, REV, MD, Others
• Biosecurity
• Cleaning and Disinfection + Downtime
• Beware “Clean / New House Syndrome”
• Some benefit with formaldehyde

47. Control of Disease
• Seroconversion of Breeders
• Once neutralizing antibodies are present shedding generally stops
(exceptions in some isolates)
• Natural Exposure – Litter, Faeces
• Beware what you bring in (i.e. Mycoplasma / Salmo)
• Live Un-attenuated Vaccine
• Serotype 8b (Australia)
• Inactivated Vaccines - Serotypes 4, 5 & 8 available
• Autogenous Vaccines

48. 48
Promoting Sero-conversion

49. 49
FAV Inactivated Vaccines
Poultrymed (accessed 5/09/14)

50. Control of Disease
• Supportive Treatment
• BLOOD BIOCHEMICAL CHANGES IN BIRDS WITH
INCLUSION BODY HEPATITIS AND THE EFFECT OF
SUPPORTIVE TREATMENTS DURING OUTBREAKS
• D. VenneA and Y. ChorfiB – Western Poultry Diseases
Conference 2011
• Treatment:
• Treatment consisted in the addition of 125 g of sodium bicarbonate
plus 400 g of sugar in 576 L of drinking water.

51. Application BioChek FAV ELISA
• SPF Monitoring Confirming Negative Status
• Monitoring BREEDERS Natural Seroconversion
• 12-18W of age > 90% POSITIVE
• Vaccination Monitoring of BREEDERS
• After Vaccination with FAV vaccines
• >90% POSITIVE
• Disease Monitoring BREEDERS

52. Application BioChek FAV ELISA
• DOC Titer – Monitoring of Mab Transfer
• Disease Monitoring BROILERS > 35D
• Suggested Horizontal Transmission Protection
• Compare clinical vs non-clinical serology
• AMT > 6500 associatied clinical disease
• Non-clinical flocks have AMT < 5000
• Vaccination Monitoring of BROILERS

53. Baselines BioChek
FAV ELISA Test Kit
Provisional Baselines
Vaccine AMT CV %POS SUSPECT TITER CV
Broiler
Breeders Inactivated / Natural SC 12000-30000 <35% >90% >15000-18000 <35%
Broilers None <5000 >40% >6500 <35%
These guidelines are based on our experience and information from our clients.
BioChek does not accept any responsibility for the results using these guidelines.
These guidelines are subject to change without notice

54. Summary
• FAV are world wide distributed viruses that affect poultry
in a wide array of manifestions that vary from mild to
very severe forms
• FAV diagnosis is attained by combination of: clinical
history, serology, and molecular techniques.
• ELISA has been proved to be an useful tool
• Prevention of FAV starts by achieving seroconversion of
parent flocks prior to lay and avoiding immunosupression

55. THANK YOU
rafaelmonleon@biochek.com