If you know surgical procedure, and how to anesthesize the animals: Anesthesize the animal either by isoflurane or ketamine/xylazine. Shave the belly, wipe with iodine solution and 70% ethanol as per your approved animal protocol. On lateral lower side of belly (slightly above testis) make a small cut with skelpal blade on the skin, cut the muscle layer to get to epididymis, pull out the epidiymis which will bring testis upward. Tie the connecting tubes (plus blood vessels) with testis with a suture, than cut the testis out. Similarly you do on the other side. Close the area by suturing muscle layer with absorbable 5-0 suture and outer skin can be sutured with non-absorbable 5-0 suture or use staples. Generally surgeries are done on a warm pad around 37C. Rest general surgery precautions. I will recommend to practice on a dead animal if you have available.

Thanks! I have done gonadectomies with adult animals using a similar procedure, but am uncertain about doing them in animals where the testes have not descended yet. If I am following your guide, you make two incisions on the lower belly (one on either side), then go through the muscle. Are the testes easily visible from there? Once I find them, I can use the same general procedure used for adults for tying them off and suturing the incisions

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