1 Pathobiology and Impact of Chicken Anemia Virus Haroldo Toro, DVM, PhD Professor Department of Pathobiology Chicken infectious anemia virus 1979 1979 Japan Japan (Yuasa) (Yuasa) 1981 1981 Germany Germany (von (von Bülow Bülow) 1981 1981 Sweden Sweden (Engstrom Engstrom) 1989 1989 USA USA (McNulty; (McNulty; Rosenberger) Rosenberger) Worldwide distribution Worldwide distribution H. Toro 2009
27
Embed
Pathobiology and Impact of Chicken Anemia Virus · 1 Pathobiology and Impact of Chicken Anemia Virus Haroldo Toro, DVM, PhD Professor Department of Pathobiology Chicken infectious
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Toro, H., S. Ewald, and F.J. Hoerr (2006). Avian Diseases, 50:124-126.
H. Toro 2009
CAV is heat stable and unaffected by ether,
chloroform or low pH. Most disinfectants are
relatively ineffective. Eradication NOT possible.
H. Toro 2009
3
Chicken Anemia VirusFamily: Circoviridae
Genus: Girovirus
Genome: Single stranded circular DNA
Envelope: Non
Morphology: icosahedral particles of 22-26 nm
Viral proteins
• VP1 is the only capsid protein
• VP2 has phosphatase activity and participates in the capsid formation as a chaperon by allowing VP1 to fold
• VP3, or apoptin induces cell death by apoptosis
Replication: Lymphoid cells (MSB1, & other)
Serotypes: 1
Transmission: Vertical & horizontal
CAVCAV2298 nt2298 nt
VP2VP2
VP1VP1
VP3VP3
Van Santen et al, 2004
H. Toro 2009
CAVCAV2298 nt2298 nt
VP2VP2
VP1VP1
VP1 HV region
VP3VP3
CAVCAV genomegenome
VP3VP3 VP1VP1
VP2VP2 HV Region
Portion Sequenced
823 nt
2298 nt
H. T. 2009
Van Santen, V., F.J. Hoerr, K. Joiner, C. Murray, N. Petrenko, & H. Toro (2004). Avian Diseases
48:494-504.
4
Sequence Origin (Year) 22 75 97 139 14405A Alabama (98) Q I L Q Q26 Alabama (98) Q I L Q Q55 Alabama (98) Q I L Q Q57B Alabama (98) Q I L Q Q58 Alabama (98) Q I L Q Q69B Alabama (98) Q I L Q Q73 Alabama (98) Q I L Q Q05B Alabama (98) N I L Q Q28B Alabama (98) N I L Q Q57A Alabama (98) N I L Q Q70 Alabama (98) N V M K E03-4876 Alabama (03) N V M K E28A Alabama (98) H I L K E52 Alabama (98) H V M K E69A Alabama (98) H V M K E01-4201 Alabama (01) H V M K ECIA-1 U.S. N I L Q Q704 Australia H I L Q QTR20 Japan H I L Q QL028 U.S. H T L Q Q26P4 U.S. H V M K EA2B Japan H V M K ECux-1 Germany H V M K DCAU269/7 Australia H V M K EAustralian Australia H V M K E
Amino acid positionHV regionPolymorphisms in
VP1 amino acid sequence among Alabama CAV sequences
V - Valine (Val)
L - Leucine (Leu)
I - Isoleucine (Ile)
M - Methionine (Met)
H - Histidine (His)
K - Lysine (Lys)
Q - Glutamine (Gln)
N - Asparagine (Asn)
E - Glutamic Acid (Glu)
D - Aspartic Acid (Asp)
T - Threonine (Thr)
Van Santen, V., F.J. Hoerr, K. Joiner, C. Murray, N. Petrenko, & H. Toro (2004). Avian Diseases 48:494-504.
H. Toro 2009
CAV signs: Uneven pullets; mortality
usually < 20%.
H. Toro 2009
5
0
50
100
150
200
250
300
350
400
0 7 14 21 28
Weight (g)
Days p.i.
Weights
Uninfected
CAV oral
CAV i.m.
CAV signs: Reduced Weight Gain (SPF chicks
inoculated at 1 day of age by the IM or oral routes with CAV isolate 03-4876).
Van Santen, V., F.J. Hoerr, K. Joiner, C. Murray, N. Petrenko, & H. Toro (2004). Avian Diseases 48:494-504.
H. Toro 2009
CAV signs: Anemia resulting from infection
of hemocytoblasts in the bone marrow
H. Toro 2009
6
0
5
10
15
20
25
30
35
40
45
0 7 14 21 28
Hematrocrit (%)
Days p.i.
Hematocrits
Uninfected
CAV oral
CAV i.m.
CAV signs: Anemia (SPF chicks infected at day 1 of age with CAV isolate
03-4876 via the oral or IM routes).
Van Santen, V., F.J. Hoerr, K. Joiner, C. Murray, N. Petrenko, & H. Toro (2004). Avian Diseases
48:494-504.
H. Toro 2009
CAV signs: Hemorrhages
H. Toro 2009
7
Trombocytes in peripheral blood of chickens inoculated with strain Gifu-1
0
5
10
15
20
25
30
35
40
0 4 8 12 16 20 24 28 32 36 40
Th
rom
bo
cyte
s x
103m
m3
Days after Inoculation
Control
CAV
Tanigushi et al., (1983)H. Toro 2009
CAV: Thymic lesions
Control
H. Toro 2009
8
Control
Experimental infection with CAV 10343 in 10Experimental infection with CAV 10343 in 10--ww--old broiler old broiler
breedersbreeders
Toro et al. (1997) Avian Pathology 26:485-499. H. Toro 2009
Lymphocyte depletion: Infection of T lymphocytoblasts in the thymic