Puncture of the rumen must be reserved for cases of primary meteorism after the other methods have failed and when... the … is immediate danger of death.
In some cases puncture of the rumen, particularly if performed by laymen, may cause a more or less extensive peritonitis or the adhesion of the rumen to the abdominal wall, which will subsequently endanger the health of the animal, more or less.
Puncture of the rumen is performed with a long trochar held in the closed hand; it is pushed (contained in its protecting tube) into the most prominent point of the left flank or into the center of a line which connects the external angle of the ileum with the middle portion of the last rib. An incision into the íkin may have been made previously. The point of the trochar is directed towards the right elbow. After penetration the stiletto is withdrawn and it or a thin rod is uFed to remove particles of food which may collect in the tube of the trochar. In order to prevent too sudden congestion of the abdominal vessels or rupture of vessels, or anemia of the brain, it is advisable to let the gases escape gradually. The tube of the trochar should then be closed with a cork and left in place for several hours, safely secured by a bandage wound around the rump of the animal.
In an emergency, puncture of the rumen may be performed with a strong pointed knife. The latter, first carefully cleaned, is held with its blade towards the front and is pushed 8 to 10 cm. deep into the rumen ; it is then rotated at a right angle in order to produce a gaping wound. The punctured wound usually heals rapidly, but a wound which has been made •with the knife should be closed by two or three sutures.
The Aida's Uruguay meat is selling today in Eretz Yisroel.
The hole can be seen & inspected, others claim that it's a tiny hole which is not visible. According to some Rabonim's understanding of the procedure (the facts don't bear it out) almost all milk in the world would also be "Ossur" as it is too small of a hole to check.
The facts as we seem to be satisfied at this time is:
Large puncture that can be examined for evidence of "treifis".
The mere fact that others aren't profecient in checking doesn't change the facts.