Contributed Papers: Posters Pathology |
CLINICAL AND
PATHOLOGICAL CHANGES IN CHICKENS (Gallus domesticus)
EXPERIMENTALLY INFECTED WITH Eimeria acervulina (TIZZER,
1929) OOCYSTS.
MACHADO, R. Z.1; ALMEIDA,
K. S.1; FREITAS, F. L. C.1 and MACHADO, C. R.2.
1 Department of Animal Pathology Sao Paulo
State University, Jaboticabal - Sao Paulo
2 Department of Animal Physiology Sao Paulo State
University, Jaboticabal - Sao Paulo. Av. Prof. Paulo
Donato
Castellane, s.n., Zona Rural, CEP: 14884-900.
Email: cmachado@fcav.unesp.br, fone (fax): (016) 3209-2656
In the present
study, clinical signs and pathological changes were
evaluated for thirty days in chickens experimentally
infected with E. acervulina. One hundred and eighty
Cobb male broiler often days of age were randomly
distributed into three groups (A: inoculated with
1 x 106 oocysts; B: inoculated with 1 x 105 oocysts;
C: inoculated with distilled water) of sixty birds.
Iso-nutritional and iso-energetic diets without anticoccidial
drugs were offered ad libitum to the chickens. Two
chickens of each group were daily sacrificed. The
pathological and clinical changes were identical in
all groups, despite being more intense in group A.
On the 1st DPI, both infected groups showed duodenum
hyperemia, which developed as congestion on the 2nd
DPI. The congestion remained present until the 30th
DPI, and was associated to thickening of the gut mucous
membrane. On the 2nd DPI, the two infected groups
still presented petechial hemorrhages in the duodenum,
which progressed to the jejunum and ileum. After the
5th DPI, a mucus exsudate was present in the lumen
of the small intestine, especially in the duodenum.
Other findings were food retention in proventriculus
and gizzard, gall bladder full of liquid, pale yellow
liver, and pale muscles. The clinical signs after
the 4th DPI were: anorexia, apathy, and diarrhea.
Other findings were digested blood in the feces, associated
or not with the presence of small whitish streaks.
Microscope examination showed immature oocysts attached
to the intestinal mucous membrane. The results demonstrate
that chickens experimentally infected with E. acervulina
present progressive intestinal lesions of variable
intensity, and that these abnormalities are the main
cause of reduction of bird performance.