Box for Observation of Living Organs in situ and for Abdominal Surgery in the Sculpin

Abstract

The operating box herein described was developed for use in 2 studies upon the sculpin (Myoxocephalus octodecimspinosus), a common marine teleost. Grafflin and Ennis 1 reported experiments upon the blockage of the gastrointestinal tract, and Grafflin and Eisenberg 2 upon the direct observation of the living kidney. There is obviously a wide field for comparative studies in the fishes in which abdominal surgical procedures and direct observation of living organs in situ would play an important part. The sculpin is readily available for experimental work; and the operating box which we have developed has been so satisfactory in our experience that it is described here in the belief that it will prove useful to other workers. The box is illustrated in Figures 1 and 2.

With the use of water outlets C and C', the water level in the box is usually maintained at a sufficiently high level. With some larger specimens a higher level is necessary to insure complete covering of the head, and in these cases the rubber tubing is switched from C to D, and the opening at C is plugged. The rather tight fit of the animal between the clamps, and the upward projection of the pectoral fins, suffice to maintain a higher level in the anterior than in the posterior chamber under these conditions.

A constant stream of sea water is supplied through the inlet B. In the experiments previously reported urethane anesthesia was used. Anesthesia was rapidly induced by immersing the fish in a 1% solution of urethane in sea water in a separate chamber. The animal was then transferred to the box, and anesthesia was maintained throughout the experiment by a 0.25% solution of urethane in sea water.