Observations on the motility and fertilizing ability of ram epididymal spermatozoa

Abstract

Summary. Fertilizing ability of epididymal ram spermatozoa was determined after intra uterine insemination of 47 ewes ; the fertility profile obtained was similar to the one established on rodents and boar. The middle corpus has an essential role in the development of the motility and fertilizing capacity of epididymal spermatozoa.The fertilizing ability of epididymal spermatozoa and its endocrine control have been studied in rodents (Bedford, 1975 ; Orgebin-Crist, Danzo and Davies, 1975) ; fertilizing ability first appears in spermatozoa from the corpus epididymis. In the sow, pregnancies have been obtained after insemination of boar epididymal spermatozoa (Holtz and Smidt, 1976 ; Hunter, Smidt and Henfrey, 1976). Fertilizing ability in this species also first appeared in spermatozoa from the corpus epididymis. There is no data available on the development of fertilizing ability of ram spermatozoa during transit through the epididymis. It is known, however, that the permeability of the spermatozoon membrane is modified in the corpus (Ortavant, 1953). This maturation process might coincide with the appearance of fertilizing ability. We therefore undertook a physiological study of the maturation of ram epididymal spermatozoa by intrauterine insemination of ewes at induced ovulation during the breeding season. Materials and methods.Ovulation was induced in forty-seven 2-3-year old nulliparous Ile-de-France ewes (Colas, 1975). 57 hours ± 1 after PMSG injection, they were inseminated into the uterine horn by laparotomy under fluothane anaesthesia. Epididymides from 6 adult Ile-de-France rams were subdivided into distal caput, middle and distal corpus and proximal and distal cauda. Sperm suspensions were prepared by maceration of epididymal tubules in a solution of skimmed milk (Colas, 1975) ; 200 !Ll of a suspension of epididymal spermatozoa (100 X 10 6 spz/ml) were introduced into both uterine horns at 1 cm from the uterotubal junction, and the ewes were inseminated. Spermatozoa from the distal caput show a light pendular movement of the tail, too slight to move the head of the cell. The amplitude of this movement sharply increased in spermatozoa from the middle corpus, giving the cells progressive motility. The percentage of motile spermatozoa progressively increased along the length of the epididymis : 1 in the distal caput, 5 in the middle corpus, 56 ! 9 in the distal corpus, 66 ! 5 in the proximal cauda and 83 + 4 in the distal cauda. The difference between the distal corpus and the distal cauda was significant (P < 0.02).The proportion of stained forms was elevated in the distal corpus (42 rL 5 p. 100) but decreased in the distal cauda (14 ! 3 p. 100). The number of abnormal spermatozoa (decapitated and distal droplets) was less than 5 p. 100.C. Fertilizing capacity of epididymal spermatozoa.1. The pregnancy test at day 18 showed that the fertilizing ability was zero for spermatozoa from the distal caput (0/8), very low for those from the middle corpus (1/8), higher for those from the distal corpus (7/8) a...

Regional differences in the morphology of the goat epididymis: A light microscopic and ultrastructural study

“…While comparing luminal-fluid proteins in different regions of the ram epididymis, Dacheux and Voglmayr (1983) reported the occurrence of five new proteins (32k, 37k, 62k, 82k, and 180k) in the body of the epididymis that are absent in the initial segment of the epididymis as well as in the blood. Furthermore, this is also the body region of the epididymis, especially its distal part, where sperm of most species first exhibit the abilities to move in a forward direction and fertilize ova (Bedford, 1966;Hunter et al, 1976;Fournier-Delpech et al, 1977, 1979.…”

Epididymal sperm maturation in the ram : motility, fertilizing ability and embryonic survival after uterine artificial insemination in the ewe

“…Epididymal spermatozoa were obtained from different segments of the epididymidis caput (distal), corpus (I = middle, 11 = inferior middle and III = distal part), and cauda (proximal and distal) according to Fournier-Delpech et al (1977). The sperm density was estimated and the spermatozoa were diluted to a final concentration of 20 x 10 6 total cells/200 y l .…”

“…However when ewes were inseminated with high number of motile spermatozoa, ES was 0, 77, 86, 100 and 86 p. 100 with spermatozoa from the corpus I --!-II, the corpus III, the proximal cauda, the distal cauda, and the ejaculate respectively. Thus, the sperm from middle corpus are totally unable to produce viable lambs.In the ram the development of sperm fertilizing ability in the epididymis coincides with the development of progressive motility (Fournier-Delpech et al, 1977) in a maturation process similar to the one described in rodents (reviews of OrgebinCrist et al,1975OrgebinCrist et al, , 1976Bedford, 1975) or in the pig (Holtz and Smidt, 1976 ;Hunter et al, 1976). However, in the rabbit embryonic mortality is increased after fertilization by immature spermatozoa from the corpus epididymis (Orgebin-Crist, 1969 ; OrgebinCrist and Jahad, 1977).…”

Management of Reproduction in Farm Animals: Present and Future

“…With available sperm freezing techniques, several authors set out to circumvent the cervix and to inseminate directly into the uterine cavity where a smaller number of sperm is required to fertilize ova. Since the first experimental surgical uterine inseminations (Trounson & Moore, 1974;Fournier-Delpech et al, 1977), it has been established that a small number of spermatozoa (10 to 20x10G) deposited in the uterine cavity through the uterine wall is sufficieftt for a high rate of pregnancy. High fertility has also been reported following laparoscopic intrauterine insemination with fresh semen (Killen & Caffery, 1982;Tervit at al., 1984).…”