EQUINE CLINICAL PATHOLOGY - Rossdale & Partners

T h e B e a u f o r t c o t t a g e l a b o r a t o r i e s
accidental cervical injury. With the hand
holding the forceps held against the mare’s
buttocks (to avoid injury to the uterus if
the mare moves suddenly) maintaining
the forceps in the uterus, the manipulating
hand and arm are then withdrawn from
the vagina and placed in the rectum. The
forceps are then palpated and advanced
into one or other of the uterine horns. The
jaws of the forceps are then opened and
a fold of endometrium is gently pushed
into the jaws, which are then closed, the
biopsy is completed and the forceps are
withdrawn from the uterus and vagina.
Tissues are carefully removed from the
forceps with fine forceps to avoid artefactual
damage and are fixed immediately in
Bouin's fluid. A fine-tipped sterile swab may
be used to sample the inside of the jaws of
the biopsy instrument for bacterial culture.
Sometimes more than one endometrial
fold is removed and then the smaller one
may be placed into transport medium for
bacterial culture.
Endometrial biopsy samples should be
referred to a laboratory that is specifically
experienced in both equine endometrial
histopathology and equine gynaecology,
in order to receive a meaningful
interpretation.
Testicular Biopsy
Testicular biopsies are best obtained by
conventional wedge resection with the
horse under general anaesthesia in order
to provide adequately interpretable tissues
and to avoid accidental injury to the
testicular artery, by blind needle biopsy,
which may have fatal consequences. The
testicle is examined by ultrasound scan for
visible pathology and best site for sampling
and the scrotum is prepared as for surgical
intervention. Automated punch biopsy and
ultrasound guided techniques are available
but the relatively small tissue samples
are better suited to specific research
requirements. Great care must be taken to
avoid injuring the testicular artery.
Testicular tissues should be fixed
immediately in Bouin's fluid.
Ileal biopsy
Using our state-of-the-art microwave
processing system, same day results can
be provided for fixed tissue specimens.
Ileal biopsies may be indicated to attempt
to confirm or deny a clinical diagnosis of
equine dysautonomia (‘grass sickness’),
where exploratory laparotomy is indicated.
At exploratory laparotomy, a transmural,
i.e. full-thickness, longitudinal ellipse of
ileum, approximately 15mm by up to
10mm is excised at the proximal end of
the ileocaecal fold, midway between the
mesenteric and antimesenteric borders.
The tissue is placed immediately into
10% formol saline and processed for
histopathological examination. The ganglia
in the myenteric plexus between the
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