The operator places himself close to the animal’s back. The incision may be made in one of three different places.
Fig. 322.—Genital organs of the sow. 1, Ovary; 2, horn of the uterus; 3, uterus; 4, rectum; 5, vagina; 6, bladder; 7, kidney; 9, intestine.
Certain practitioners recommend a vertical incision about 2 to 2¼ inches in length, commencing at the external angle of the ilium, or ⅓ of an inch in front of it, and prolonged downwards; others make a horizontal incision parallel with the vertebral axis; and, lastly, some believe that an oblique incision following the direction of the “cord of the flank” is just as advantageous. A vertical or oblique incision is probably the best.
The operation comprises four stages:
First stage. Incision of the skin and subjacent muscles.
Second stage. Perforation of the peritoneum and discovery of the ovaries.
Third stage. Ablation of the ovaries or of the ovaries and horns of the uterus.
Fourth stage. Suture of the wound.
The tissues are divided layer by layer. The skin is formed into a longitudinal fold and divided in a vertical direction, and the subjacent muscular layers are then divided with the bistoury. The tissues are next broken through layer by layer with the index finger until the parietal peritoneum is reached. This membrane is then fissured, or at least scraped with the nail, and perforated with a sudden sharp thrust of the index finger.