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  • Author: D. R. ACKERMAN x
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D. R. ACKERMAN

The enzyme hyaluronidase is believed to permit spermatozoa to disperse or to penetrate the cumulus oophorus (Kurzrok, Leonard & Conrad, 1946; Swyer, 1947a; Austin, 1948). The mechanism by which hyaluronidase mediates fertilization may not be the same in all species; Swyer (1947b) has discussed the release of enzyme by spermatozoa as a function of cell concentration, and of hyaluronidase concentration in the suspending medium. He noted that spermatozoa appear to be diffusing preformed hyaluronidase, and not to produce the enzyme. This was also the finding of Bergenstal & Scott (1948). It is well established for several species including man (Bergenstal & Scott, 1948) that hyaluronidase is a product of the seminiferous epithelium (Swyer, 1947b), and associated with spermatozoa, not with the accessory reproductive organs. In particular, the cellular enzyme was shown

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B. FJÄLLBRANT and D. R. ACKERMAN

A serious difficulty in the use of frozen-preserved human semen for donor insemination is our inability to predict, without rather extensive clinical trials, which specimens will be successful in producing conception and which will be generally infertile. Predictions cannot be made from the pre-freeze motility of the specimen (Behrman & Sawada, 1966) nor, in our experience, from the fertility of a donor's freshly ejaculated specimen. A technique for determination of cervical mucus penetration by spermatozoa using capillary tubes (Kremer, 1965) has been thoroughly investigated and found to have several advantages (Kremer, 1968). This capillary tube test has been shown to be a reasonably reliable predictor of the fertility of fresh human semen (Fjällbrant, 1968). Specifically, a penetration by the leading spermatozoa in the capillary tube of
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D. R. ACKERMAN and J. D. ROUSSEL

A series of recent studies has been devoted to the systematic examination of characteristics of the semen of subhuman primates, with particular reference to the successful freeze-preservation of these specimens. Roussel & Austin (1967a) showed that trypsin will liquefy the coagulum which appears in these ejaculates without harm to the motility of the sperm cells and the survival rates of cells from five species after 3 days' storage in liquid nitrogen have also been reported (Roussel & Austin, 1967b). The initial content of fructose, lactic acid and citric acid in the frozen semen of animals from eleven species was studied (Ackerman & Roussel, 1968) in order to establish the extent of variability among

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D. R. ACKERMAN and J. D. ROUSSEL

Comparative studies of semen characteristics in subhuman primate species should be of value in the selection of appropriate species for experiments in reproduction. In addition, basic information obtained in such studies may be helpful for the successful preservation of frozen semen and insemination. These techniques will probably be essential in the maintenance of large primate colonies. Finally, comparative information of this kind should be of interest to students of primate classification. Animals providing specimens for this study were selected from over 800, representing a dozen or more species, located at the Delta Regional Primate Research Center, Covington, Louisiana. The classification employed is that outlined in the Progress Report of the Primate Centers' Committee

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D. R. ACKERMAN and U. A. SOD-MORIAH

Summary.

Glycerolated semen specimens of several donors were examined for DNA content after refrigeration at +6° C for 7 days, and after storage in liquid nitrogen for periods ranging from 2 to 75 weeks. Fresh specimens were also studied. DNA determinations were made in each case by both Feulgen microspectrophotometry (in arbitrary units) and by the Webb-Levy chemical determination. The quantity of DNA per cell in arbitrary units and in mg × 10−9 remained constant after refrigeration, and after freezing-preservation for all time periods studied. Discrepancies between the two kinds of determination, and the concept of embryonic mortality due to aged spermatozoa are discussed.

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W. F. VESTAL, D. R. ACKERMAN and DEBORAH REJENT

Rabbit spermatozoa have to undergo capacitation within the female reproductive tract for successful fertilization to occur (Chang, 1951; Austin, 1951). Although no morphological changes have been directly associated with the process per se (Bedford, 1970), oviducal and uterine fluids have been shown to stimulate sperm respiration in vitro (Olds & VanDemark, 1957; Hamner & Williams, 1963; Foley & Williams, 1967; Black, Crowley, Duby & Spilman, 1968; Iritani, Gomes & VanDemark, 1969) and in vivo (Hamner & Williams, 1963; Iritani et al., 1969). Ericsson, Buthala & Norland (1971) have fertilized rabbit ova in vitro with spermatozoa to which Sendai virus had been adsorbed. These spermatozoa had no previous contact with the female reproductive tract. In consideration of this apparent capacitating effect of Sendai virus, the present study examines the effect of the