D.B. Morais

Stages and duration of the seminiferous epithelium cycle in the bat Sturnira lilium

Knowledge of the stages that compose the seminiferous epithelium cycle (SEC) and determination of the duration of spermatogenic processes are fundamental for the accurate quantification of the dynamics of spermatogenesis. The aim of this study was to characterize the stages that compose the SEC of the bat Sturnira lilium, including evaluation of the average frequency of each of these stages throughout the year and calculation of the duration of the spermatogenic process. An ultrastructural characterization of the formation of the acrosomal cap was also performed. Testicular fragments were processed for morphological and immunohistochemical analysis as well as ultrastructural analysis using transmission electron microscopy. According to the tubular morphology method, the SEC in S. lilium is divided into eight stages, following the pattern found in other mammals. Primary spermatocytes were found at zygotene in stage 1 of the cycle. There was no variation in frequency of each of the stages over the seasons, with stage 1 being the most frequent, and stage 7 the least frequent. The duration of one seminiferous epithelium cycle was 3.45 days, and approximately 15.52 days were required for the development of sperm from spermatogonia. Ultrastructural characterization allowed the formation of the acrosomal cap in round spermatids to be monitored. In conclusion, the stages that compose the SEC in S. lilium are generally similar to those described for other mammals, but the duration of the spermatogenic process is shorter than previously recorded for mammals. The presence of primary spermatocytes at zygotene in stage 1 of the cycle is probably due to the longer duration of this stage.

The spermatogenic process of the common vampire bat Desmodus rotundus under a histomorphometric view

Among all bat species, Desmodus rotundus stands out as one of the most intriguing due to its exclusively haematophagous feeding habits. However, little is known about their spermatogenic cycle. This study aimed at describing the spermatogenic process of common vampire bats through testicular histomorphometric characterization of adult specimens, spermatogenic production indexes, description of stages of the seminiferous epithelium cycle and estimative of the spermatogenic process duration. Morphometrical and immunohistochemical analyzes for bromodeoxiuridine were conducted under light microscopy and ultrastructural analyzes were performed under transmission electron microscopy. Vampire bats showed higher investment in gonadal tissue (gonadosomatic index of 0.54%) and in seminiferous tubules (tubulesomatic index of 0.49%) when compared to larger mammals. They also showed a high tubular length per gram of testis (34.70 m). Approximately half of the intertubular compartment was found to be comprised by Leydig cells (51.20%), and an average of 23.77x106 of these cells was found per gram of testis. The germline cells showed 16.93% of mitotic index and 2.51% of meiotic index. The overall yield of spermatogenesis was 60% and the testicular spermatic reserve was 71.44x107 spermatozoa per gram of testis. With a total spermatogenesis duration estimated at 37.02 days, vampire bats showed a daily sperm production of 86.80x106 gametes per gram of testis. These findings demonstrate a high sperm production, which is commonly observed in species with promiscuous mating system.

Microscopia e morfometria de componentes tubulares de testículos de coelhos suplementados com geleia real

This study aimed to investigate the effects of royal jelly on spermatogenesis in rabbits treated with different concentrations of RJ (Control; 0,5mg/day; and 1,0mg/day) using testicular morphometry. There was no significant difference between the body weight (T1= 3.20±0.19kg; T2= 2.96±0.30kg; T3=3.21±0.37kg) and gonadal weight (T1= 2.36±0.33g; T2= 2.53±0.33g; T3= 2.64±0.39g), gonadossomatic index (T1= 0.15±0.02%; T2= 0.17±0.03%. T3= 0.16±0.02%) and tubulossomatic index (T1= 0.06±0.01%; T2= 0.07±0.01%. T3= 0.06±0.01%) between treatments, showing that the percentage of body mass, and the percentage of seminiferous tubules allocated in testis were similar in the 3 experimental groups. Similarly, the mean diameter of the seminiferous tubules (T1= 225.95±13.27µm; T2=239.68±21.50µm; T3= 231.57±15,94µm), the height of the seminiferous epithelium (T1=66,05±5,37µm; T2=73.47±9.11µm; T3=63.34±4.79 µm) and length of seminiferous tubule for testis (T1=46.63±13.44m; T2=43.58±12.17m; T3=46.96±9.54m) and per gram of testis (T1=19.50±2.68m; T2=17.12±3.91m; T3=17.78±1.98m) did not differ statistically. It was concluded that supplementation with royal jelly, at the doses used, did not alter the testicular parameters evaluated here.

Germ cells and the seminiferous epithelium cycle in the wild rodent Oxymycterus rufus (Rodentia: Cricetidae)

Oxymycterus rufus is a wild rodent that inhabits one of the world hotspots known as the Atlantic Rain Forest in Brazil. Due to the lack of reproductive data regarding such species, the present study aimed to describe O. rufus spermatogenic process through morphometrical and stereological analyses. To do so, testicular fragments of five sexually mature males were routinely processed for light and transmission electron microscopy. The results showed that each seminiferous epithelium cycle corresponded to 6.58 days, while the entire spermatogenic process lasted 29.61 days. The coefficient of spermatogonial mitoses was 5.64 and 2.79 spermatids were produced from each primary spermatocyte in pachytene. The spermatogenesis yield was 11.98 cells. The Sertoli cell index was 4.29, while its overall support capacity was 8.21 cells. The testicular sperm reserve was 183.5 x 10 6 cells, while 962.00 x 10 6 spermatids were found per gram of testis. The daily sperm production per testis and per gram of testis was 28.56 x 10 6 and 73.13 x 10 6 sperm, respectively. Therefore, the short duration of the seminiferous epithelium cycle along with rapid production of sperm indicates that O. rufus shows high efficiency in spermatogenesis.

Preservação do sistema genital de chinchila (Chinchilla lanigera) para avaliação em microscopia de luz

The preservation of chinchilla genital organs using a fixed solution of paraformaldehyde 10% buffered and a saturated solution of Bouin during 4, 12 and 18 hours of fixation, inclusion in paraffin and staining with hematoxylin-eosin was evaluated. The Bouin solution with 12 hours of fixation was the best protocol of fixation for the ovaries, oviduct, uterus and vagina, resulting in little tissue retraction and better cellular integration when compared to the other fixing times (4 and 18 hours). The fixation with paraformaldehyde showed good results of tissues fixation. Chinchilla genital organs can be preserved with paraformaldehyde 10% buffered and Bouin solution using 12 hours of fixation.

Morphophysiological parameters of the testicles of mice (Mus musculus) supplemented with royal jelly.

The effects of royal jelly on the morphophysiological parameters of mice (Mus musculus) testicles were studied. Fifty-eight male Swiss mice were evaluated. They were four-month old and were randomly distributed in six treatments: T1: physiological solution, intraperitonial route; T2: 0.1mg of royal jelly, intraperitonial route; T3: 0.2mg of royal jelly, intraperitonial route; T4: distilled water, orally; T5: 0.1mg of royal jelly, orally; and T6: 0.2mg of royal jelly, orally. After 45 days of supplementation with royal jelly, the animals were weighted, slaughtered, and the testicles collected, included in paraffin, and stained with haematoxylin-eosin. No differences among treatments were observed for: body and testicular weights, gonadossomatic index, tubular diameter, epithelial height, total length of seminiferous tubules, tubular length per testicle gram, tubulossomatic and leydigossomatic indexes and the value of volumetric proportion related to tunic, seminiferous epithelium, blood vessel, and lymphatic vessel. Differences between T1 and T3 about the seminiferous tubules and intertubular space were found.The effects of royal jelly on the morphophysiological parameters of mice (Mus musculus) testicles were studied. Fifty-eight male Swiss mice were evaluated. They were four-month old and were randomly distributed in six treatments: T1: physiological solution, intraperitonial route; T2: 0.1mg of royal jelly, intraperitonial route; T3: 0.2mg of royal jelly, intraperitonial route; T4: distilled water, orally; T5: 0.1mg of royal jelly, orally; and T6: 0.2mg of royal jelly, orally. After 45 days of supplementation with royal jelly, the animals were weighted, slaughtered, and the testicles collected, included in paraffin, and stained with haematoxylin-eosin. No differences among treatments were observed for: body and testicular weights, gonadossomatic index, tubular diameter, epithelial height, total length of seminiferous tubules, tubular length per testicle gram, tubulossomatic and leydigossomatic indexes and the value of volumetric proportion related to tunic, seminiferous epithelium, blood vessel, and lymphatic vessel. Differences between T1 and T3 about the seminiferous tubules and intertubular space were found.

Morphophysiological parameters of mice (Mus musculus) testicles supplemented with royal jelly

The effects of royal jelly on the morphophysiological parameters of mice (Mus musculus) testicles were studied. Fifty-eight male Swiss mice were evaluated. They were four-month old and were randomly distributed in six treatments: T1: physiological solution, intraperitonial route; T2: 0.1mg of royal jelly, intraperitonial route; T3: 0.2mg of royal jelly, intraperitonial route; T4: distilled water, orally; T5: 0.1mg of royal jelly, orally; and T6: 0.2mg of royal jelly, orally. After 45 days of supplementation with royal jelly, the animals were weighted, slaughtered, and the testicles collected, included in paraffin, and stained with haematoxylin-eosin. No differences among treatments were observed for: body and testicular weights, gonadossomatic index, tubular diameter, epithelial height, total length of seminiferous tubules, tubular length per testicle gram, tubulossomatic and leydigossomatic indexes and the value of volumetric proportion related to tunic, seminiferous epithelium, blood vessel, and lymphatic vessel. Differences between T1 and T3 about the seminiferous tubules and intertubular space were found.The effects of royal jelly on the morphophysiological parameters of mice (Mus musculus) testicles were studied. Fifty-eight male Swiss mice were evaluated. They were four-month old and were randomly distributed in six treatments: T1: physiological solution, intraperitonial route; T2: 0.1mg of royal jelly, intraperitonial route; T3: 0.2mg of royal jelly, intraperitonial route; T4: distilled water, orally; T5: 0.1mg of royal jelly, orally; and T6: 0.2mg of royal jelly, orally. After 45 days of supplementation with royal jelly, the animals were weighted, slaughtered, and the testicles collected, included in paraffin, and stained with haematoxylin-eosin. No differences among treatments were observed for: body and testicular weights, gonadossomatic index, tubular diameter, epithelial height, total length of seminiferous tubules, tubular length per testicle gram, tubulossomatic and leydigossomatic indexes and the value of volumetric proportion related to tunic, seminiferous epithelium, blood vessel, and lymphatic vessel. Differences between T1 and T3 about the seminiferous tubules and intertubular space were found.