The Output of Spermatozoa in Rams I. Relationship with Testicular Output of Spermatozoa and the Effect of Ejaculations

Abstract

The mean daily output of spermatozoa was estimated for each of eight Merino rams from the numbers of spermatozoa eliminated from the urogenital tract both in the urine and in spontaneous discharges over 20 days (DSOU) and by doubling the number of spermatozoa collected daily from one testis by a rete testis catheter (DSOT). The two estimates (DSOU and DSOT) were highly correlated (r = 0·999), but the DSOU was usually a little lower than the DSOT. The mean difference was 3·4%.The effect of 20 ejaculations collected over 2 days was studied in four rams. The DSOU was severely depressed for a period of 9-16 days after the ejaculations but when the number of spermatozoa ejaculated was added to the DSOU in this period the mean daily spermatozoan output was similar to that in the periods immediately preceeding and succeeding it.It is concluded that the daily spermatozoan production of rams may be estimated accurately from the number of spermatozoa eliminated daily from the urogenital tract. It is unlikely that significant numbers of spermatozoa are resorbed or phagocytosed in the epididymides of normal rams.

The Output of Spermatozoa in Rams II. Relationship to Scrotal Circumference, Testis Weight, and the Number of Spermatozoa in Different Parts of the Urogenital Tract

“…found that the number of testicular spermatozoa was not significantly correlated with the epididymal spermatozoan reserves and stressed the independence of the testicular spermatozoan production and the storage of spermatozoa in the excurrent duct system. The highly significant correlation between DSOU and the epididymal spermatozoan reserves in the present study is contrary to this finding especially as, in the ram, most of the spermatozoa produced by the testis are eliminated from the urogenital tract (Lino and Braden 1972). Indeed, the interrelationship between spermatozoan reserves, DSOU, and spermatozoan transit time indicates that the total number of spermatozoa in the urogenital tract would provide a measure of the rate of spermatozoan production.…”

“…One drop of semen was taken for examination and the remainder of the ejaculate was washed into the urine collector. It has been demonstrated that the rate of spermatozoan output measured by DSOU is not affected by ejaculation provided that the spermatozoa removed by ejaculation are included with the number of spermatozoa voided (Lino and Braden 1972). The number of spermatozoa removed in a drop of semen once a week was found to be less than 0·5% of the total number of spermatozoa produced.…”

“…The mean daily output of spermatozoa from the urogenital tract (DSOU), which includes all spermatozoa eliminated in urinations, spontaneous emissions, and ejaculations, has been found to be within 4% of the mean number of spermatozoa passed daily from a catheter implanted in the rete testis (Lino and Braden 1972). The agreement between these two estimates of spermatozoan production was much closer than that found between DSOU and estimates of daily spermatozoan output obtained from an exhaustive ejaculation test (Lino, Braden, and Turnbull 1967) and indicated that DSOU gives a very good estimate of the daily spermatozoan production of the testis.…”

Testicular and Epididymal Sperm Numbers and Related Parameters in the Developing Awassi Ram

“…By counting spermatozoa passed through a rete testis catheter, Australian workers (Voglmayr et al 1966(Voglmayr et al , 1967Setchell et al 1969) indicated that a typical Merino ram testis would produce about 16 x 10 6 -18 x 10 6 sperm per gram of parenchyma per day. According to Lino and Braden (1972), sexually rested Merino rams aged 4-5 years produced on the average 5·8 X 10 9 sperm per day as counted from daily sperm output from the urogenital tract.…”

Frequent semen collection and sperm reserves of the male Angora goat (Capra hircus)

“…It is possible to estimate the testicular production of spermatozoa indirectly on the basis of high correlations between traits of reproductive tracts (rabbit: Orgebin-Crist, 1968;boar: Kennelly & Foote, 1964;bull: Almquist Weisgold & Almquist, 1979;ram: Lino, 1972; Lino & Braden, 1972). For example, there is a good correlation between the number of spermatozoa stored in the genital tract and the testicular production of spermatozoa in the ram (Ortavant, 1958;Lino, 1972).…”