Daily Sperm Production by the Rabbit

T ESTICULAR spermatid reserves have been quantified for bulls, buffalo-bulls, deer, boars, rabbits, guinea pigs, roosters and humans. Generally, a modification of the technique described by Amann and Almquist (1961) has been used. Daily sperm production can be calculated by dividing the value for testicular spermatid reserves by a time divisor which is the number of days of production these reserves represent (Amann and Almquist, 1962). Based on knowledge of the duration of one cycle of the seminiferous epithelium and morphology of the spermatids, Amann and Almquist (1962) concluded that for dairy bulls testicular spermatid reserves represented 3.27 days' sperm production. They cautioned, however, that this time divisor of 3.27 days was not valid for other species or homogenization techniques. When sampling errors associated with hemacytometry are minimized, the time divisor is the major potential source of error in determining daily sperm production from testicular spermatid reserves (Amann and Almquist, 1961, 1962). This report describes an improved method for determining spermatid reserves useful for most species and establishes the time divisor necessary for calculating daily sperm production of rabbits. Estimations of the time divisor as determined by morphologic and autoradiographic methods are compared since autoradiographic studies might be impractical with some animals.