Sperm Attractant Research Articles

Control of Sexuality in Golenkinia

Sperm formation can be induced in strains 929 and 930 of the oogamous genus Golenkinia by nutrient depletion, specifically the deprivation of either nitrogen or phosphorus, but not by a decrease in total molarity or by a change in pH. Nitrogen (or phosphorus) concentration plays a controlling role in the presexual vegetative growth and the actual period of induction. During the latter, the rate of gametogenesis is inversely proportional to the nitrogen level and can be completely stopped by nitrogen added as many as 8 hr after resuspension in a medium lacking nitrogen. White light of an intensity of 10,000 ergs per cm2 per second is required during the first 9 hr of resuspension in an inducing medium although a lower intensity is sufficient if given for longer periods. Sexuality in Golenkinia responds most strongly to red or blue light, indicating that photosynthesis is important in this process. Fertilization in strain 929 requires at least 0.001 m calcium. No evidence was found for the action of hormones either in sexual induction or in chemotactic sperm attraction.

Development and regression of hexestrolinduced changes in the spermatic tract of the rabbit

The author studied the changes that occur in the spermatic tract of rabbits during and after the administration of hexestrol. Under the influence of hexestrol administration lasting for from 3 to 311 days, atrophy of the epithelium occurs along with partial collapse of various portions of the duct system, as well as edem and moderate cellular infiltration of the distal portion of the duct system. Metaplasia of the epithelium into the stratified squamous type, with atypical keratinization, was observed in the distal portion of the ductus epididymidis in 5 out of 41 animals; in one rabbit the ampulla of the vas deferens was also involved. From two to seven months after the cessation of hexestrol administration (which was continued for three montns in this group) a slow restoration of specific differentiation occurred. The dependence of atrophic and regenerative changes in the vas deferens on similar changes in the testes is emphasized.

Fecundity of male rabbits as determined by “dummy matings”

A method of obtaining samples of semen from rabbit males by means of a dummy and artificial vagina is described. The volume of the semen, and the number of spermatozoa per cm. (density) and the total number of spermatozoa in the sample have been measured. The data obtained from these measurements have been analysed under the following headings:1. Relation between total volume and total number of spermatozoa. With an increase in the total volume of the ejaculate there is an increase in the total number of spermatozoa, but the relationship is not linear. The density of spermatozoa varies considerably.2. Seasonal variation. Seasonal variation in sperm production is not marked in these data. There is slight tendency for the numbers to be highest in the early part of the year and lowest in August and September when the animal is moulting.3. Individual variation. In each individual, variation is considerable. Differences between individuals are not marked, but as most of the animals were of low average fertility, it is probable that this result is not typical of male rabbits in general.4. Effect of successive matings with in a short period. In successive matings the number of spermatozoa diminishes rapidly. As the density is not much affected, the diminution is due to reduction in the volume of the ejaculate.5. Relation between the number of spermatozoa in the ejaculate and the number in the various sections of the spermatic tract. After a series of samples had been obtained, some males were killed and an estimate made of the number of spermatozoa present in various parts of the tract. From the results it is concluded that on ejaculation the vas deferens is practically emptied and that some sperm in the ejaculate come from the cauda epididymis.6. Observations on sexual behaviour. The sexual pattern of the male rabbit is described and the relation between sexual stimulation and sex drive is discussed.