Journal of Entomology and Zoology Studies 2017; 5(1): 229-234

E-ISSN: 2320-7078 P-ISSN: 2349-6800 JEZS 2017; 5(1): 229-234 Histological and Morophometrical study of male © 2017 JEZS reproductive tract in Rousettus aegyptiacus Received: 07-11-2016 Accepted: 08-12-2016 (Mammalia: Megachiroptera) in Iran

Esmat Abas Fard Department of Biology, Jahrom Branch, Islamic Azad Esmat Abas Fard and Farangis Ghassemi University, Jahrom, Iran Abstract Farangis Ghassemi In this study, the male reproductive tract of fruit bat (Rousettus aegyptiacus) was surveyed. 5 bats were Department of Biology, captured by mist net on July and were anesthetized in laboratory, weighted and dissected. Their genital Jahrom Branch, Islamic Azad University, Jahrom, Iran organs were measured, and fixed in formalin 10%. The sections (5 µm) were prepared by tissue processing, stained with haematoxylin and eosin and mounted. Obtained data were analyzed by ANOVA and t-test. Finding showed that testes were in , and the weight of right and left were different significantly (P>0.05). The epididymides were located at the medial border of the testis, and cylindrical was projected cranially. A , paired ampullary gland, large seminal vesicle, and Cowper’s glands were observed. Histological features of these organs like to the other mammals, and numerous spermatozoa and concentrated secretion were seen. According to these results, this species is in active phase of sexual response cycle in summer.

Keywords: Accessory gland, Bat, Germ cell, histology, testicle

1. Introduction Chiroptera with more than 1350 known species is the second large order among mammals. The Frugivorous bats disperse seeds and pollinate flowers by feeding on fruit, pollen and nectar [1]. Insectivore bats play an important role in biological pests control by feeding them [2]. So they play an ecological and economic role in our community [3, 4], but little is known about

the reproductive cycles of them. Bats vary widely in morphology, ecological behavior and reproductive adaptations. Rousettus aegyptiacus, belong to family Pteropodidae is a fruit bat and the only megabat which lives in Iran, and due to the warm climate of the southern Iran, the most population of them live in this area [5]. [6, 7] Reproductive system in bat such as the other mammals is varies . Some species breed all [8] [9, 10] years , and others have seasonal reproduction . Cyclic and acyclic breeding pattern was reported for fruit bat [10], but the environmental factors may affect the reproductive cycle and structure of it. Reproduction system in bat contains two , seminiferous tubules, ductus deferens, [11] [12] , and accessory glands . The testicle in some bats such as Rhinopomatidae is [13] [8] in the abdomen and in some species of Rhinolophidae and Pteropodidae is external. The aim of present study was to know the male reproductive tract of R. aegyptiacus in Iran.

2. Material and Methods: Considering the effect climate on the morphological and

anatomical variation in animals, the present study was conducted.

2.1 Study region: Sangtrashan is an artificial cave with 150 years old in the south of Iran at 53˚ 34' E and 28˚ 33' N. The cave area is 20000 m2 with 3m height and 12 large entrances (Fig 2). Many tunnels and holes are in the terminal of the cave which is a suitable roost for bats. 10

species of bat lives in this cave, and also R. aegyptiacus was observed in a large colony.

Correspondence 2.2 Sampling: 5 male adults of R. aegyptiacus, were captured using mist net. It's the only Farangis Ghassemi megabat of Iran, so was identified easily. Department of Biology, Jahrom Branch, Islamic Azad University, Jahrom, Iran ~ 229 ~ Journal of Entomology and Zoology Studies

2.3 Dissection and morphometric study: The captured bats were transferred to the lab, anesthetized with ether, weighed with digital Balance (0.01 g) and the genital macroscopic features were examined. Then they were dissected and removed their reproductive tract. The length of testicles, genital tubules and accessory glands were measured with a caliper. Also these organs were weighed and fixed in 10% formalin.

2.4 Slid preparing and histological study: The fixed samples were placed in autonomic tissue processor: dehydrated in graded series of ethanol (70%- 100%), then impregnated with paraffin and serial section (5μ) were obtained. They were subjected to Haematoxylin and Eosin (H&E) stains. The prepared slides were mounted with binocular light microscope (40 x, 100 x) and photomicrograph was prepared.

Fig 1: Rousettus aegyptiacus T: Testis P: Penis 2.5 Statistical analysis: Obtained data was analyzed by using

statistical Software, SPSS (18) and ANOVA test, and the measure of left and right organs were compared by t-test.

3. Results 3.1 Macroscopic study: The reproductive tract of R. aegyptiacus like other vertebrates had two testicles which located in the thin scrotum, outside of the abdomen (Fig 1). The scrotum was a little darker than the body skin with thin hairs (Fig 1). The testes were ovoid shaped, milky, vascular and bulky (Fig 2). The weight of left testis were more than right ones significantly (P>0.05) but no significant difference was in length of them (Table 1). Two epididymides, convoluted tube, were attached to the medial border of testes and include three segment include

prominent head, body and distinguished tail, that continues to the . They were milky and were surrounded by a Fig 2: Sectioned reproductive tract of Rousettus aegyptiacus mass of fat (Fig 2). No significant difference was between the E.h: Head of epididymis E.b: Body of epididymis E.t: Tail measurement of right and left epididymis (Table 1). of epididymis T: Testise B: Bladder P.g: Prostate gland V.d: Vas deferens I: Intestine The vas deferens was thicker than the epididymis and a paired

ampullary glands were at the end of it. The length of the epididymis and the most of the vas deferens placed in the scrotum (Fig 2). Elongated, cylindrical and pinkish penis was projected cranially (Fig1, 3). The penis has a prominent head, glans, and hairless body except for its base (Fig 1). The glans was short and narrow. Accessory gland includes a paired oval and milky seminal vesicle that suited on the upper part of the bladder, ampullary glands, prostate and Cowper’s gland (Fig 3). Two seminal vesicle were very large (Table 1; Fig 3), but no significant difference (weight and length) was seen between left and right of them (Table 1). The lobular prostate gland was at the base of the bladder, and a paired small Cowper’s gland was under it (Fig 3).

Table 1: The measurement of male reproductive organs in Rousettus aegyptiacus (Mean ± SEM)

Rousettus aegyptiacus Left Right Body Weight (g) 133.30±1.84 Fig 3: Accessory glands of Rousettus aegyptiacus Penile length (cm) 1.50±0.23 T: Testise P.g: Prostate gland S: Seminal vesicle A: Ampulla of vas deferens P: Penis . U: Penile weight (g) 0.48±0.07 Testicular weight (g) 1.70±0.13 1.48±0.19 Testicular length(cm) 1.19±0.17 1.10±0.28 3.2 Microscopic study: The overlying layers of testes include Epididymal weight (g) 1.82±0.18 1.69±0.11 tunica vaginal and thick (Fig 4A) with some Epididymal length(cm) 2.38±0.20 2.29±0.31 white and brown fat cells (Fig 4B). The testes were lobular Seminal vesicle weight(g) 1.82±0.03 1.74±0.17 and include a number of seminiferous tubules which lined by Seminal vesicle length(cm) 1.28±0.26 1.22±0.12 a stratified epithelium, germ cells in different phases and Prostate weight(g) 0.95±0.12 0.89±0.29 Sertoli cells (Fig 4C). Spermatogonia, primary and secondary ~ 230 ~ Journal of Entomology and Zoology Studies

, , and spermatozoa were found in connective tissue or (Fig 4D). Lamina seminiferous tubules (Fig 4C), and also spermatozoa were propria, connective tissue, with capillary and muscle cell were present in the epididymides (Fig 5A). Leydig cells with oval observed inter seminiferous tubules (Fig 4D). The and a large nucleus, eosinophilic cytoplasm and some blood anastomosing channels of the (R) lie within the vessels were seen in interstitial tissue (Fig 4C). In cross loose connective tissue of the mediastinum testis, and sections of testicular tissue, rete testis, a network of a thin Junctions of these channels and (Ed) can be tube, with columnar epithelium was seen between loose seen (Fig 4D).

Fig 4: Micrographs of the testis of Rousettus aegyptiacus. A: Testis T.al: Tunica albuginea T.v: S.m: smooth muscle L.c: Lydig cell V: Vessel S.t: Seminiferous tubules G.c: Germ cell E.d: efferent duct B: WFC:White fat cell BFC: Brown fat cell I.c: Interstitial cell C: Sp: Spermatogonia SpI: I SpII: Spermatocyte II Sc: M.C: Myoid cell L: Lumen of seminiferous tubules C.T: Connective tissue D: rete testis V.e: Vas efferent MT: Mediastinum testis

The epithelium of the epididymis was ciliated pseudostratified (Fig 7A). Glans has thick keratinized stratified squamous columnar (Fig 5C) which in the head of it is thickest part (Fig epithelium. Also epidermal spines were seen (Fig 6 C). The 5A) and a lot of villus like projections, stereocilia, has placed pseudostratified columnar (glandular) epithelium with stereo inner side of it (Fig 5C). Abundance circular smooth muscle cilia was seen in seminal vesicle and secretion droplets were cells surrounded this duct in the three segments spatially in in its lumen (Fig 7A). It includes numerous tubules which the tail (Fig 5C). Vas deferens with abundance of sperm also were separated by interlobular septa, and abundance of was seen (Fig 5D). The epithelium of this duct is smooth muscle was in the septa (Fig7B). pseudostratified columnar with stereocilia and smooth muscle The fibromuscular capsule covered prostate, and columnar randomly arranged (Fig 5D). and transitional epithelium cells, with secretory activity, lined The large masses of smooth muscle and elastic fibers in the it (Fig 7C). The Prostate tissue had numerous acinus with connective tissue was seen that surround the cavernous spaces dark staining which indicates that they are serous glands (Fig (Fig 6A, B), and small os penis (OP) were in the glans (Fig 7D). 6B), Thick tunica albuginea surrounded corpus cavernosum

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Fig 5: Photomicrographs of the genital tubules of Rousettus aegyptiacus. A: Head of Epididymis B: Body of Epididymis C: Tail Body of Epididymis D: Seminal vesicle Ps. E: Pseudostratified.E LCT: Loose connective tissue BC: Basal cell Vi: Villus (Stereocilia) L.E: Lumen of epididymis L: Lumen N: Nucleus SP: Sperm L.P: Lamina propria SCE: Stratified columnar epithelium

Fig 6: Micrographs of the penis of Rousettus aegyptiacus A: Penile Urethra CSP: Cavernous space U:Urethra, lumen C.T: Connective tissue CC: Corpus cavernosum B: Body of penis V:Vein CS: Corpus spongiosum OP: Os penis Co. E: Stratified Columnar epithelium L.P: Lamina propria RP. m: Retractor penis muscle G: tubular alveolar gland C: Glans KSSE: keratinized stratified squamous epithelium E:Epiderm D: Dermis Bc: Basal cell A: Artery K: keratin Sp: Epidermal spine ~ 232 ~ Journal of Entomology and Zoology Studies

Fig 7: Micrographs of the accessory glands of Rousettus aegyptiacus A, B: Seminal vesicle C, D: Body of prostate gland G,d: gland duct T: Trabecula Se: Secretion I.s: Interlobular septum Ps.E: Pseudostratified epithelium

4. Discussion [23]. Testosterone is produced by the testicular Leydig cells, so Reproductive strategies in order chiroptera even within a the high density of them is a good marker for activity of testes species of them are diverse [14], and depending on the latitude [20]. The long epididymis spatially its prominent head and tail and where that bats inhabit [15, 16]. So it is expected that in this species of bat (Table 1) is a convenient site for storage variation in the macroscopic and microscopic structure of of sperm, so they may store spermatozoa for periods of time genital organs is seen in bat species [17]. Rousettus aegyptiacus [24]. A paired seminal vesicle even larger than testes, on the almost inhabit in humid roosting and warm climate [18] which contrary almost carnivorous mammals, were seen in studied accordance to research region. samples (Fig 2). The size of testes and seminal vesicle (Table The environmental factors such as temperature and 1) related to body mass [25] and indicate spermatic activity, availability of food resources are important factors those which accordance to seasonal changes, so the examined affecting bat reproductive cycles [6], on the other hand, the specimens were in active phase [26]. The numerous germ cells relation of physiology and anatomy can’t be ignored. and leydig cells which secrete testosterone for successful Although some bats have abdominal testes like bats belongs breeding were in the large testes (Fig A-D). Although to family Phyllostomidae [19] and Noctilionidae [6, 20], but R. spermatogenic activity was found throughout the year for R. aegyptiacus, similar to family Vespertilionidae, has scrotum aegyptiacus in Egypt and South Africa [23], but the peak of testes [8] which aid to their thermoregulatory and sperm seminal secretion for this species is during copulation in July viability. The color of scrotum skin was slightly darker than and august [8] that accordance to time of our sampling. body skin. It is due to the melanin presence that necessary for Although (vesicular gland) are absent in testes protection against harmful effects of sunlight spatially some carnivorous mammals and some of the bats such as where the bats are exposed to solar radiation [21, 22]. family Phyllostomidae [11], but this species like to Eidolon Tunica albuginea in this species unlike almost domestic helvum, another species of Pteropodidae family, has a paired mammals consist loose connective tissue with smooth muscle oval seminal vesicle [27]. Prostate gland in the most of the (Fig 6A). The numerous muscle cell, elastic fibers and sinuses mammals is seromucous gland [25], but concentrated secretion formed erectile tissue. The testicular size of many animals and its dark stain showed that it may is a serous gland (Fig C, varies seasonally and is associated with the time of D). Duo to the presence of abundance smooth muscle and . Observation all of the germ cell types, a lot connective tissue with elastic fiber (Fig 6A, B), we couldn’t of spermatozoa in the epididymides spatially in the tail and a determinate type of penile tissue, vascular or fibroblastic (Fig large number of leydig cells in seminiferous tubules indicated 6A, B). The collection of fat bodies is seen in some bats [28] that spermatogenesis was occurring in summer, although which aid them as a rapid path of energy production in continuously spermatogenesis was reported for this species response to reproductive activity [29, 30]. On the other hand this ~ 233 ~ Journal of Entomology and Zoology Studies

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