Determination of cutting point of oviduct in minimally invasive surgical technique in Persian sturgeon (Acipenser persicus) and Starry sturgeon (Acipenser stellatus)

Similar to other Chondrostean fish, Persian sturgeon (Acipenser persicus Borodin, 1897) and Starry sturgeon (Acipenser stellatus Pallas 1771) have got Gymnovarian ovaries, and structure form of their reproduction system is such that eggs cannot readily leave it. In minimally invasive surgical technique, a small incision is made in the wall of oviduct so that the eggs can easily leave it with the minimal manipulation and also the broodstock can survive. The aim of this work is to determine the distance between gonopore and incision area according to size and species which results in a more accurate and flawless incision. The results of this study showed that the distance between gonopore and conjuncture area of the two oviducts depends on species and size of fish; this distance in Persian sturgeon with 115-191 centimeters fork length and Starry sturgeon with 122-143 centimeters fork length were 4.2-6.3 and 3.8-4.5 centimeters, respectively. This distance is more than the incision depth that is generally made on the wall of one of the oviducts.