Little-known accessory glands in female Zygaena moths (Lepidoptera, Zygaenidae)

In the female genital system of Zygaena moths, an additional pair of accessory glands is present besides the Y-shaped sebaceous gland. The term 'Petersen's glands' is proposed for these organs. Anatomy, histology, histochemistry and cytology of Petersen's glands of Zygaena trifolii are described. The sac-like glands, situated in the extreme dorsocaudal part of the abdomen, can be divided into a purely secretory part consisting of acini with large pear-shaped gland cells and a reservoir part with combined secretory and storage function. The secretory cells of the acini are penetrated by long curved ductules or secretory end apparatuses having feltwork consisting of very fine filaments. The cytoplasm is characterized by abundance of smooth tubular endoplasmic reticulum (ATER) and the presence of peroxisomes. This cytoplasmic organization is in accordance with the chemical composition of the sticky secretion, which evidently consists completely of lipids. The ultrastructure of the epithelium lining the reservoir of the glands has both traits of secretory and of transporting epithelia. Besides contributing to the secretion, it may be involved in absorption of residual aqueous phase from the contents of the reservoir.     

Sperm displacement behavior of the cuttlefish Sepia esculenta (Cephalopoda: Sepiidae)

Sperm displacement behavior of cuttlefish (Sepia esculenta) was observed in a tank. Before ejaculation, male cuttlefish used their arms III to scrape out sperm masses attached to the buccal membranes of females. The removed sperm mass debris was directly visible and countable. Active sperm were present within the removed sperm debris, implying that the aim of this behavior is to remove competing male sperm. However, many sperm masses remained on the female buccal membrane even after the removal behavior, showing that sperm removal in S. esculenta is incomplete. The duration of sperm removal (an indicator of male investment in that process) was unaffected by the body sizes of mated pair, the duration of spermatangia placement at the current mating (for the hypothesis that the sperm removal serves to creat attachment space of spermatophores), or the estimated amount of sperm masses deposited from previous matings. Moreover, male S. esculenta performed sperm removal regardless of whether the last male to mate with the partner was himself, suggesting males remove not only the sperm of rivals but also their own. Although the number of removed sperm masses increased with the time spent on removal of sperm, male cuttlefish may shorten the duration of sperm removal to avoid the risk of mating interruption. We conclude that this time restriction would likely influence the degree of partial sperm removal in S. esculenta. A digital video image relating to the article is available at .This revised version was published online in April 2005 with corrections in the abstract.     

The role of the accessory reproductive glands and genital ducts in egg pod formation in female Schistocerca gregaria

Removal of the accessory reproductive glands in female Schistocerca gregaria does not prevent the formation of eggplugs as expected. The egg pods formed are incomplete, with froth in the egg plug partially lacking. The extent of collapse is dependent on the time of removal of the glands. These results suggest that the genital ducts (egg calyces and lateral oviducts) play a significant role in the production of egg pod material, and the accessory glands probably participate in the process. Ligation of the glands has the same effect on egg pod structure; secretion accumulates in the glands indicating that, although the contribution made to the egg pod by the glands is small, they are not vestigial and are not acting simply as reservoirs for secretions produced distally. Cautery of the Comstock-Kellogg glands produces no visible change in egg pod structure or in method of formation, and thus their function remains undetermined. In the absence of the ventral median pouch egg masses are laid without the plug. A thin layer of nonvacuolated material is smeared over the walls of the oviposition hole, suggesting that the secretions produced in the upper regions of the genital ducts are added to or modified by an additional secretion from this gland, before being released to the exterior.     

Characteristics of aminopeptidase activity of female housefly reproductive accessory glands

Proteolytic activity was detected in crude extracts of female reproductive accessory glands and the following characteristics of the principal aminopeptidase activities were determined: substrate specificity, pH optima, molecular weights, and effects of inorganic salts. The greatest aminopeptidase activities were found with the β-naphthylamides of: alanine at pH 7.5 and 9.5, leucine at pH 8.0, and methionine at pH 6.5. The methionine-specific activity in the crude extract was stimulated 3 times by 100 mM MgCl₂, CaCl₂, NaCl, or KCl. Inhibition was noted, and ID₅₀ was determined for each of the other principal substrates with the following salts: CdCl₂, CaCl₂, ZnCl₂, HgCl₂, MgCl₂, and MnCl₂. Molecular weights, estimated on Sephadex G-200 and on Sepharose-6B, were found to be around 210 000 for each of these principal aminopeptidase activities in the crude extract.     

Cuttlebone morphology limits habitat depth in eleven species of Sepia (Cephalopoda: Sepiidae)

The cuttlebone is a rigid buoyancy tank that imposes a depth limit on Sepia, the only living speciose cephalopod genus with a chambered shell. Sections of 59 cuttlebones from a geographically diverse sample of 11 species were examined using confocal microscopy. Sepia species that live at greater depths had thicker septa and less space between pillars than did shallow species. A plate theory analysis of cuttlebone strength based on these two measures predicted maximum capture depths accurately in most species. Thus cuttlebone morphology confers differing degrees of strength against implosion from hydrostatic pressure, which increases with increasing habitat depth. Greater strength may come at the cost of increased cuttlebone density, which impinges on the cuttlebone's buoyancy function.     

Accumulation of secretory proteins in the accessory reproductive glands of the male migratory grasshopper, Melanoplus sanguinipes: A developmental study

Production of secretion in the accessory reproductive glands of male Melanoplus sanguinipes has been examined by electrophoresis and radiolabelling. The secretion of each group of tubules (long hyaline glands, white glands, short hyaline glands, and seminal vesicles) can be resolved into more than 20 protein bands and includes several glycoproteins and, in the long hyaline and white glands only, lipoproteins. Each group of tubules has a characteristic pattern of synthesis and accumulation of proteins; that is, specific proteins appear in the secretion at particular times during sexual maturation. In allatectomized insects, the long hyaline glands accumulate very little secretion; the white glands and short hyaline glands accumulate about one-third the normal amount; and accumulation in the seminal vesicles is not affected by the operation. Allatectomy exerts its effect by inhibiting the synthesis of particular proteins. The observations are discussed in terms of juvenile hormone-specific protein synthesis in the accessory reproductive glands.     

Male insect accessory glands: Functions and control of secretory activity

Summary

Paralleling the diversity of the class Insecta, the male accessory glands (MAG) exhibit a wide range of form, and their secretion serves a variety of functions, including spermatophore and mating plug formation, sperm activation, provision of nutrients to females, and, through production of fecundity-enhancing and/or receptivity-inhibiting substances, modification of female reproductive behavior. In most insects, juvenile hormone (JH) is important in the regulation of MAG secretory activity; specifically, JH controls the production of particular proteins in the secretion. However, the production of some proteins appears not to be influenced by JH; rather, their synthesis is regulated by ecdysteroids. During sexual maturation, JH and ecdysteroids seem to interact to bring about a specified temporal sequence of protein synthesis in the MAG.     

Structure of male accessory glands of Bolivarius siculus (fischer) (Orthoptera,Tettigoniidae) and protein analysis of their secretions

In Tettigoniidae (Orthoptera), male reproductive accessory glands are involved in the construction of a two‐part spermatophore; one part, the spermatophylax, is devoid of sperm and considered a nuptial gift. The morphology, ultrastructure, and secretion protein content of the male reproductive accessory glands from Bolivarius siculus were investigated. Two main groups of gland tubules open into the ejaculatory duct: the “first‐order” glands, a number of large anterior tubules, and the “second‐order” glands, smaller and more numerous tubules positioned posteriorly. Along with a further subdivision of the gland tubules, we here describe for the first time an additional gland group, the intermediate tubules, which open between first and second‐order glands. The mesoderm‐derived epithelium of all glands is a single layer of microvillated cells, which can be either flattened or cylindric in the proximal or distal region of the same gland. Epithelial cells, very rich in RER and Golgi systems, produce secretions of both electron‐dense granules and globules or electron‐transparent material, discharged into the gland lumen by apocrine or merocrine mechanisms, respectively. With one exception, a unique electrophoresis protein profile was displayed by each of the gland types, paralleling their unique morphologies. To assess the contribution of different types of accessory glands to the construction of the spermatophore, the protein patterns of the gland secretions were compared with those of the extracts from the two parts of the spermatophore. All samples showed bands distributed in a wide range of molecular weight, including proteins of very low molecular mass. However, one major high molecular weight protein band (>180 kDa) is seen exclusively in extracts from the first‐order glands, and corresponds to an important protein component of the spermatophylax. J. Morphol., 2009. © 2009 Wiley‐Liss, Inc.     

Morphological analysis of the male reproductive accessory glands of the bat Artibeus lituratus (Phyllostomidae: Chiroptera)

Bats are distributed worldwide from tropical to temperate regions. Despite their wide geographical radiation and advances in studies using evolutionary approaches, aspects related to the reproduction of these animals remain poorly explored, especially those related to the male reproductive accessory glands (RAGs). Thus, the aim of this study was to analyze the morphophysiology of the male RAGs in the bat Artibeus lituratus. The RAGs in A. lituratus are composed of a compact intra‐abdominal glandular complex, consisting of the prostate with two prostatic regions (ventral and dorsal), plus Littre glands and a pair of extra‐abdominal bulbourethral glands. The ventral region of the prostate has an epithelium with variable morphology, due to its holocrine type of secretion. In contrast, the dorsal region has a typical cubic‐to‐columnar pseudostratified epithelium. Both regions contain two cell types, basal and secretory cells. Similar to the epithelial morphology, the secretion also varies, with the ventral region containing numerous PAS‐positive globular vesicles, whereas the dorsal region has a more fluid, hyaline and PAS‐negative secretion. Littre glands are dispersed in the connective tissue of the urethra, while the bulbourethral glands are located in the penile root, both glands with cubic‐to‐columnar pseudostratified epithelium and globular PAS‐positive secretion. The results demonstrate that the RAGs of A. lituratus are composed of two prostatic regions, ventral and dorsal, and urethral and bulbourethral glands, with no seminal vesicles. Each prostatic region has unique and distinctive characteristics, with the ventral region presenting an exclusive holocrine nature and the dorsal region having similarities to the ventral prostate of rodents.     

A histological study of the accessory reproductive organs of female Loligo forbesi (Cephalopoda: Loliginidae)

In Loligo forbesi Steenstrup, the female reproductive system consists of the ovary and accessory reproductive organs which include the oviducal gland, the nidamental gland, the accessory nidamental gland and seminal receptacle. Histological studies were made on the accessory reproductive organs of female L. forbesi. The various changes observed during maturation are described and the functional significance discussed. The secretions produced by the oviducal gland and nidamental gland apparently form the egg coats. The seminal receptacle serves to store spermatozoa after mating. The function of the accessory nidamental gland is unknown.     

Development of the accessory reproductive glands and genital ducts in female Schistocerca gregaria

The accessory reproductive glands of female S. gregaria are tubular extensions of the paired genital ducts, which in the mature female contain large amounts of a proteinaceous secretion used in the formation of the egg pod. In the 4th and 5th-instar female the glands are indistinguishable from the remainder of the mesodermally derived genital ducts. Towards the end of the 5th stadium, however, the accessory gland region only acquires characteristic convolutions which persist throughout the adult stages. At this time the epithelium of the entire ducts becomes reorganized into a unicellular epithelium. Only one cell type occurs throughout the length of the glands, and also in the egg calyces and lateral oviducts. The cells are inactive immediately after final ecdysis and remain in this state until the level of juvenile hormone in the haemolymph rises. The hormone acts directly on the cells triggering a rapid proliferation of organelles associated with protein secretion, and thereby increasing the volume of apical cytoplasm. Microvilli develop at the luminar plasma membrane, while irregular infoldings form at the base of the cells. As the gland matures the major organelle, the rough endoplasmic reticulum, changes from the lamellar to the vesicular form. Secretion is released into the lumen by the ‘microapocrine’ method.     

Size and protein content of accessory glands in adult male Caloptilia fraxinella in different physiological states

Reproductive diapause is a strategy employed by some insects to coordinate reproduction with the appropriate environmental conditions for mate location and offspring development. Male Caloptilia fraxinella Ely (Lepidoptera: Gracillariidae) eclose in July in reproductive diapause, and remain unmated until May of the next year, when they emerge from overwintering sites in a reproductively active state. The present study assesses characteristics of male sex accessory glands (SAG) throughout the adult life stage when males are reproductively active and in early and late reproductive diapause. Male SAG are longer and positively correlate with moth body size when males are reproductively active in the spring compared with males in reproductive diapause in the summer and autumn. Male SAG also contain significantly more protein during the period of reproductive activity than during reproductive diapause. Access to a carbohydrate nutrition source does not impact male SAG length or protein concentration when males are reproductively active in the spring. Treatment with a Juvenile Hormone analogue in the autumn, but not the summer, tends to increase the total protein concentration compared with that of untreated control moths.     

Ultrastructure of male accessory glands of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae)

The ultrastructure of the male accessory glands of the blow fly, Chrysomya megacephala (Fabricius), was presented using light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). A pair of accessory glands was separated at opposite sites. Morphometric results using LM yield evidenced no significant difference in the median of either length or width of the left and right glands. A significant increment in both length and width was seen to plateau between three to six days. SEM observation showed that the surface of the glands revealed a faint irregular groove pattern throughout, and it was occasionally penetrated by tracheoles. Each gland was a slender, elongated sac‐like tubule having apical rounded ends, with a slight constriction at the sub‐apical part of the gland being observed occasionally. TEM analyses of three‐day‐old males showed that the glands consisted of external capsular cells with a basement membrane underneath, glandular cells, and gland lumen. The capsular cell was flat and contained a nucleus with electron dense material in the nuclear envelope. The glandular cell, appearing as columnar, consisted of a vacuolated component that contained a large oval nucleus centrally or sub‐basally located, with dense mitochondria, numerous rough endoplasmic reticulum, and secretory vesicles containing electron‐lucent materials. In the gland lumen, the cross‐section through the middle portion revealed dense secretory materials, characterized by electron‐dense materials. Some sections revealed a large lumen where secretion accumulates within the delicate sac. The seven‐day‐old glands exhibited a remarkable change in the lumen, where the whole space contained a large amount of secretory materials, with the electron‐dense materials being characterized as similar to those observed in three‐day‐old glands. About four prominent types of secretions were observed on the basis of difference in electron‐density.     

Trehalases from the American cockroach,Periplaneta americana: multiple occurrence of the enzymes and partial purification of enzymes from male accessory glands

Trehalase activities were found in several tissues of the adult American cockroach, Periplaneta americana. Among these, male accessory glands, fat body, thoracic muscle, hepatic cecum, blood and mid-gut contained high trehalase activity; activity in the male accessory gland was especially high. The enzymic properties of soluble trehalases were investigated and the enzymes from the male accessory gland were highly purified.

The properties of these enzymes were electrophoretically and kinetically distinct from each other. The presence of enzymes with somewhat different properties in different tissues suggests that trehalose utilization and trehalase activity may be regulated by way of a tissue-specific mechanism. The detailed properties of these enzymes are presented with a discussion of their regulation.     

Protein production in components of the accessory gland complex of male Melanoplus sanguinipes (Insecta: Orthoptera)

Protein production during sexual maturation or after allatectomy (followed by juvenile hormone replacement therapy) has been examined in the long hyaline glands, short hyaline glands, white glands, and seminal vesicles, which make up the accessory gland complex of male Melanoplus sanguinipes. During maturation, the amount of protein in the long hyaline glands increases about 14-fold, and in each of the other components between 5- and 6-fold. Most protein accumulates between days 3 and 5, and this is reflected in high levels of incorporation of radiolabelled leucine in this period.

The components show differential sensitivity to the effects of allatectomy. After this operation, the protein content of, and incorporation of radiolabel into, the long hyaline glands remain near the day 0 level. In the white glands and short hyaline glands, allatectomy also has a marked, though less severe, effect on protein synthesis and accumulation. The seminal vesicles are least affected by allatectomy and continue to accumulate protein (though more slowly) to about 60% of the normal level by day 10. Juvenile hormone compounds applied topically to allatectomized insects on day 2 restored the ability of the gland components to accumulate proteins, though to differing degrees. JHI is the most effective compound, stimulating synthesis and accumulation of protein to near normal levels by day 10, whereas application of JHIII or Stauffer's synthetic JH led to only partial restoration of protein synthesis in the glands.     

优雅蝈螽雄性附腺的超微结构及其腺管提取物对精子束的作用

为阐明优雅蝈螽Gampsocleis gratiosa Brunner von Wattenwyl雄性附腺的结构与功能的关系, 本文利用透射电镜(transmission electron microscope, TEM)技术研究了优雅蝈螽雄性附腺的超微结构, 利用微分干涉相差显微镜(differential interference contrast microscope, DIC)技术并结合雄性附腺匀浆提取物与精子束在体外的短暂培养, 研究了优雅蝈螽雄性附腺对精子束的作用。结果表明： 优雅蝈螽雄性附腺3类腺管组织结构相似, 腺管管壁为单层上皮细胞, 缺少内表皮, 说明其来源于中胚层。上皮细胞富含粗面内质网、 线粒体、 高尔基体, 具有分泌细胞的特点。腺管管腔中分泌物有4种形态, 即电子透明的物质、 电子致密的颗粒物质、 细纤维状物质以及绒球状物质。上皮细胞的分泌方式主要有2种, 即顶质分泌和局部分泌。乳白短腺管的匀浆提取物参与了帽状精子束解聚的过程, 乳白长腺管和透明腺管的匀浆提取物有维持精子束活性的作用。本研究结果为进一步阐明螽斯雄性附腺的生理功能奠定了基础。     

Ultrastructure of reproductive accessory glands in the female sandfly Phlebotomus perniciosus Newstead (Diptera : Psychodidae)

The paired female accessory glands of Phlebotomus perniciosus (Diptera : Psychodidae) were investigated by light microscopy, and by scanning and transmission electron microscopy. These glands undergo morphological and functional changes during oocyte development. After the blood meal, the monostratified glandular epithelium differentiates and starts to secrete. Well-developed rough endoplasmic reticulum, Golgi complexes, and membrane-bounded exocytic vesicles suggest that these secretory cells are involved in protein synthesis. As the secretory cells differentiate, the glandular lumen increases in size and fills with secretory material, consisting of globular granules of different sizes in an amorphous electron-dense matrix. The granules have an electron-translucent core and an electron-dense cortex. The morphological characteristics of the glandular epithelium and the functional role of the glands are discussed in relation to their possible contribution to the reproductive process.     

Sonomorphology of the reproductive tract in male and pregnant and non-pregnant female Rothschild's giraffes (Giraffa camelopardalis rotschildi)

The application of real-time-B-mode ultrasonography to wild and zoo animal medicine has been shown to improve the understanding of reproductive physiology in many species. Ultrasound technology is especially helpful for monitoring urogenital health, which in turn has advantages for giraffe breeding and welfare in captivity.This study aimed to ultrasonographically describe the genital organs of reproductively healthy male and female giraffes. Through the use of a restrainer, repeated rectal ultrasound examinations were performed over a 2 year period in 2.6 Rothschild's giraffes. Changes in ovarian activity were monitored throughout four different reproductive stages in the females and included immature, mature-cycling, pregnancy, post-partum-period. In the immature giraffes the ovaries showed multiple follicles of which larger ones luteinized to form pseudo-corpora lutea. By comparison, in the mature giraffes the dominant follicle reached an ovulatory diameter of 18.5 ± 0.89 mm. After ovulation, a single corpus luteum rapidly formed and reached a maximum diameter of 33.0 ± 2.4 mm on average. Pregnancy was detected for the first time by the embryonic vesicle, visualized around 28 days post copulation. Follicular development remained ongoing during early pregnancy. In the males, as in other ruminants, the bulbourethral glands and the seminal vesicles were prominent, whereas the prostate gland was indistinct.Knowledge about the reproductive tract morphology and physiology is necessary for diagnosing medical disorders and abnormalities in giraffes. The aim of this study was to help consolidate the current knowledge on basic reproductive parameters for this species.