In order to investigate the morphological characteristics of epididymal duct of the squirrel, the histological and histochemical studies were carried out. The epididymal duct can be divided into 9 segments by histological and histochemical features. Segments 1 to 5 were located in the head, segments 6 and 7 in the body, and segments 8 and 9 in the tail of the epididymis. The apical cells were numerous in the segment. Clear cells which has a compact, deeply staining nucleus and a characteristically clear cytoplasm were scattered in the epithelium throughout the duct. Interepithelial clear cells which had PAS-positive granules tended to increase in number caudally. Strong PAS-positive reaction was detected at the intralumen of the segments 3, 8 and 9. Acid phosphatase activity was relatively high in the basal cytoplasm of the segment 7, and then in the supranuclear region of the segments 8 and 9. Alkaline phosphatase activity was weakly positive or negative except the segments 3 and 4. ATPase activity was strong in the free surface of the epithelium in the head and the entire cytoplasm in the body and tail, and SDH activity was generally weak except for the body where it was more intense.

Data from 34 yearling Hereford or Angus bulls were used to investigate relationships of testicular size, quantitative rates of sperm production, Sertoli cell numbers, numbers of germ cells supported per Sertoli cell, and the efficiency of spermatogenesis to daily sperm output and seminal quality. Two ejaculates were collected by electroejaculation from each bull on each of 2 days/week throughout the study. The percentage of progressively motile sperm and the percentage of morphologically normal sperm were determined from aliquots of fresh semen. Additional aliquots of semen were frozen in glass ampules or plastic straws and subsequently evaluated for postthaw motility and percentage of sperm with intact acrosomes. Sertoli cell numbers, the numbers of germcells per Sertoli cell, and the efficiency of spermatogenesis were unrelated to the quality of fresh or frozen semen (P greater than 0.05). In first ejaculates, the numbers of sperm and motile sperm were related (P less than 0.05) to testicular parenchymal weight (r = 0.38, and 0.50), daily sperm production (r = 0.45 and 0.53), and spermatids per gram of testicular parenchyma (r = 0.35 and 0.34). Testicular parenchymal weight and daily sperm production also were related to daily sperm output and to the average daily motile sperm output of these bulls (P less than 0.05), but could account for less than 25% of the variability in these end points among bulls.

The testis and epididymis are important organs of the male reproductive system; the function is to produce, mature, transport, and store sperm. It is important to understand the localization and expression of specific proteins based for the studies of its physiological processes. In the study, we investigated the expression and distribution of galectin-3, one beta-galactoside-binding proteins, in the testis and epididymis of mouse using western blot and immunohistochemistry. Western blot analysis revealed that the expression of galectin-3, 29 kDa protein, was low in the testis. In the epididymis, high expression was detected in the body and tail part, but moderate expression in the head part. By immunohistochemical analysis, we found that positive localization of galectin-3 was detected in some myoid cells and Leydig cells in the testis, but few in the seminiferous tubules. In the epididymis, galectin-3 was intensely expressed in the epithelium of epididymis, especially in the epithelium of both body and tail epididymis. Collectively, these results suggest that galcetin-3 is constitutively expressed in the testis and epididymis of mouse with varying intensity, and the role of galectin-3 in the male reproductive organ may be involved in the specific function of its structures.

This study was performed to examine the effect of 2,3',4,4',5-pentachlorobiphenyl (PCB#118) on testis of male rats. PCB#118 (20 mg/kg/week) in corn oil was intraperitoneally injected to adult male rats for 2, 5, 8 weeks. The body and testicular weights were measured at 3, 6, 9 weeks of PCB treatment. The morphological changes in the rat testes were then analyzed by light microscopy (LM) and transmission electron microscopy (TEM). The results showed that PCB#118 caused significant change in the body weights and testicular weights. Moreover, the morphological studies that were conducted on the PCB-treated rats revealed that the number of spermatocytes and spermatids in their seminiferous tubules decreased than control group (LM). The nuclear membrane was damaged when PCB was administered to them for 9 weeks (TEM). These results suggest that the reproductive function of the adult male rats is sensitive to PCB#118, and that may affect the testicular morphology of adult male rats.

A study was conducted on the epididymis of 30 Gaddi goats, divided into three groups of 10 animals in each viz; Prepubertal (1 day old to 18 months of age), Pubertal (18 months to 5yrs of age)and Postpubertal (5yrs of age). The study revealed that all the structures of epididymis grew gradually and consistently with age; however the differential growth was more appreciable during prepubertal and pubertal stages of life than in the later phases. In one day old kids, the tubular epithelium comprised of simple columnar epithelium, which became pseudostratified columnar at six months of age. The tubular diameter and height of the epithelium and its stereocilia also increased from birth to late prepuberty. It increased further in the pubertal animals and only slightly in postpubertal animals. Histochemically the cytoplasm of epididymis was PAS positive and Sudanophilic. Moderate to strong ACPase and strong AKPase activities were observed in all the segments of epididymis, which increased with age.

Although mammals produce either sperm or eggs depending on their sex, newborn MRL/MpJ male mice contain oocytes within their testes. In our previous study, the testicular oocyte appears as early as day 0 afterbirth and has morphological characteristics as an oocyte such as zona pellucida and follicular epithelial cells. Based on the observation of F1 between MRL/MpJ and C57BL/6, one of the genes causing the appearance of testicular oocyte exists on the Y chromosome. In the present study, we found testicular oocytes within newborn AKR mice. We have also analyzed the Sry genes from several inbred mouse strains and identified a shortened glutamine repeat near the C-terminal region that is unique to MRL and AKR. These results suggest that polymorphism of glutamine repeat within SRY correlates with the appearance of testicular oocyte and this phenotype is derived from AKR, one of the original strains of MRL mice.

The effects of melatonin and Light treatments on the reproductive performance of yearling Suffolk rams were investigated. The two groups (A, n = 8; B, n = 8) were given a priming period of long days (18 h Light (L): 6 h dark (D) during 1st February to 14th March. During 14th March to 9th September, group A was exposed to local light + melatonin Implants (Regulin) at 5 weekly intervals, group B was exposed to local light + melatonin Fed (M- 5250) alongwith the feed. The group (C, n = 8) in the local light during 1st February to 14th March and during 14th March to 9th September remained on local light + melatonin implants (Regulin) at 5-weekly intervals. However, the group (D, n=8) was treated as control and kept on local light environment (Lat. 51 degree 43'N) throughout the experiment. Testis diameter, sexual behaviours and semen quality were used to assess reproductive performances. The treatment to group A & B resulted in a significant advancement in high reproductive performance. The treatment to group C indicated that the abrupt application of melatonin in mid March resulted in a weak response in terms of all the criteria of assessment. The investigation indicated that seasonal fluctuations in reproductive behaviour and semen quality may be rephrased by the application of light and melatonin treatments and that these treatments may be considered for the preparation of rams for out of season breeding.