Biology Reference
In-Depth Information
the 45 hares came from two farms in the South of the island managed by the Ente
Foreste of Sardinia. The survey was developed following three main protocols:
serological, histopathological, and biomolecular.
Blood was withdrawn individually prior to butchery, and sera obtained after
centrifugation were frozen at
18
C until serology tests were carried out with the
CIA (Medicago, Uppsala, Sweden).
All slaughtered rabbits were then inspected for macroscopic renal lesions pre-
sumably attributable to
E. cuniculi
, and a valued score was used to classify them:
0
¼
no lesions, 1
¼
localized small white spots, 2
¼
widespread presence of small
white spots, 3
¼
localized scarring, and 4
¼
wrinkle kidney.
From 22 out of 94 samples for biomolecular and histopathological surveys, DNA
was extracted with a commercial kit (High Pure Template Purification Kit, Roche),
PCR was performed according to the protocol developed by Valencakova et al.
(
2005
), and sequencing was carried out on an AB automated sequencer (Applied
Biosystems, Vienna, Austria).
8.3 Results
Six out of nine breedings monitored were serologically positive to
Encephalitozoon
spp. (66.7%), while all hares' sera tested were negative.
The prevalence for positive farms ranged from 0% (Farm 1) to 24% (Farm 2),
25% (Farm 7), and 80% (Farm 3), respectively, in MR and OB animals. MR
prevalences observed in the positive farms (No. 5) differed statistically significantly
(
2
w
¼
with 4 degrees of freedom
¼
10.32,
P
¼
0.035), while differences were not
2
with 4 degrees of freedom
¼
5.87,
P
¼
statistically significant in OB (
0.208).
Of sera examined, 18.5% (68/378) were positive, in particular 5% (13/261) of
MR and 47% (55/117) of OB. The differences between the total prevalence of OB
and MR were statistically significant (
w
w
2
Yates corrected
¼
93.89,
P
<
0.0001).
The kidneys with macroscopic lesions were 16.4% (62/378) stratified according
to the following classes of scores: score 1
¼
6.6% (25/378), score 2
¼
5.5% (21/
378), score 3
1.6% (6/378). The kidneys of
seropositive animals with the macroscopic lesions were 39.7% (27/68). The differ-
ence between the total percentage of kidneys with lesions and the seropositive
animals was highly significant (
¼
2.6% (10/378), and score 4
¼
2
0.0001). Correlation between the
lesion scores and seropositives was positive (Pearson correlation
¼
23.03,
P
w
<
¼
0.211) and
statistically significant (
P
0.0001).
Of 22 positive samples examined, eight (36.4%) were identified as
Encephalitozoon
spp. by DNA sequencing, of which six (27.3%) were also positive
by serological testing, while one sample was negative, and one was not tested
serologically. Sequences showed 100% homology to
E. cuniculi.
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