Left Oviduct Research Articles

Selected issues in local immune system of hen's reproductive tract

In terms of its anatomy and functions, the reproductive system of birds is significantly different from the one found in mammals. It consists of only the left ovary and the left oviduct, which is constantly exposed to ascending infections because of its connection with the cloaca. Hence, the proper functioning of humoral and cell-mediated local immune mechanisms in this system is very important for maintaining its physiological functions. The expression of Toll-like receptors and the presence of T and B lymphocytes have been demonstrated in both the ovary and the oviduct of chickens. CD4+ T cell subpopulation is distributed mainly in the lamina propria of the oviduct, whereas in the submucous membrane and muscular layer these cells are found less frequently. CD8+ T lymphocytes are equally distributed in all abovementioned layers of the oviduct wall. IgY+ B cells are distributed among the epithelial cells, and they are closely connected with the glandular tissue of the oviduct, mainly in the infundibulum, magnum, and uterus regions. IgA+ and IgM+ B cells are present in the entire oviduct, but mainly in the glandular tissue of the magnum. IgY+ B cells have not been detected in the ovary, unlike IgM+ B cells, which have been demonstrated in the ovary stroma. In addition to T and B cells, antigen-presenting cells are present in the follicle wall and in the oviduct. During the early stages of reproductive maturation, a decrease in the number of immunocompetent cells is observed in the reproductive system, and the local immnosuppression increases the susceptibility of birds to Salmonella Enteritidis infections. The number of T and B lymphocytes in the mucous membrane of the oviduct decreases with age, which facilitates infections of the reproductive system. Additionally, the local immune mechanisms of the reproductive system in birds involve the transfer of protective IgY, IgA and IgM maternal antibodies to hatching eggs. The local immune mechanisms of the reproductive tract are responsible for preventing infections that disturb the physiological functions of the reproductive system and for protecting eggs from contamination.

The post hatching development of the female genital system in Indigenous Mallard Duck (Anas platyrhynchos)

The current research aimed at obtaining principal data on the morphological developmental changes that could occur during the post hatching periods in the female genital system of the Indigenous Mallard ducks and to conduct that twenty (immature and mature) ducks were used. Gross findings have revealed that the left ovary in 4 weeks sold ducklings appeared small triangular in shape, located at the dorsal part of coelom in contact caudally with the cranial division of the left kidney and cranially with left lung. In 8 and 12 weeks the left ovary has enlarged showed prominent granular surface. The left oviduct appeared as thin, translucent straighten tube with unapparent regions fixed by a thin doubled folds of oviductal ligament and ureter. In mature and laying ducks, the left ovary was large and irregular in shape, and showed numerous follicles of different developmental stages. The mature and laying left oviduct was fully developed into six well distinguished regions (infundibulum, magnum, isthmus, uterus, junction region and vagina). The present study has concluded that the first twelve weeks of post hatching periods had similar morphological features and showed inert genital organs which were not completely differentiated, while the age of twenty four weeks revealed completely differentiated female genital organs with sexual activity.

Immunohistochemical localization of progesterone receptor isoforms and estrogen receptor alpha in the chicken oviduct magnum during development

In this work, the immunohistochemical expression of progesterone receptor (PR) isoforms and estrogen receptor alpha (ER-α), as well as the histomorphometric changes of the magnum region of the left oviduct from 8-day-old chicken embryos to one-month-old chickens were evaluated. Results indicate evident histological changes in the oviduct magnum during development mainly in the magnum's mucosa. Immunohistochemical analysis showed that the oviduct magnum from 8-day-old chicken embryos to one-day-old chickens did not present any PR isoform, but the oviduct magnum of one-week and one-month-old chickens expressed PR in the nuclei of all cell types. In epithelial cells, PR-B was the only isoform expressed; in muscle and serosa cells, PR-A isoform was the only isoform expressed; and stromal cells expressed both isoforms. The results also demonstrate positive ER-α immunostaining in the nuclei of different cells from embryonic life to later developmental stages of the oviduct magnum. Data indicate that the variations of ER-α or PR expression or dominance of either PR expression is differentially regulated depending on the cell type, the development of the oviduct, and in an age-specific manner. These variations in sex steroids hormone receptors are related with histological changes of the oviduct magnum through development.

A novel technique for oviduct occlusion to generate live births from cryopreserved rabbit oocytes after in vivo fertilisation

Intraoviductal transfer technique in combination with in vivo fertilisation has arisen as an effective technique to assess live births after transfer of slow-frozen oocytes in the rabbit. Nevertheless, the great disadvantage of this method is the accumulation of tubal fluid in a large number of females after clamping the oviducts. In this study, we develop an alternative method to minimise damage to the oviduct and increase the birth rate. The aims of this study were (1) to evaluate the ability of cyanoacrylate tissue adhesive to occlude the oviduct for female sterilisation; (2) to evaluate the effect of oviduct occlusion immediately after transferring fresh oocytes on in vivo fertilisation; and (3) to assess this technique to generate live births from fresh and slow-frozen oocytes. In all the experiments, recipients were artificially inseminated 9h prior to occluding the oviducts. In the first experiment, the left oviduct was blocked with cyanoacrylate tissue adhesive, while the right one was used as a control. Six days later, oviducts and uterine horns were flushed to assess embryo recovery rates. While the embryo recovery rate was 79.2% in the intact oviduct, no embryos were recovered in the blocked one. In the second experiment, fresh oocytes were transferred into both oviducts, which were immediately occluded. Six days later, the in vivo fertilisation success rate was 33.7%. Finally, in the last experiment, slow-frozen oocytes were transferred and the rate of live births was 13.2±4.5%. The study shows that when using this method the generation of live births from slow-frozen oocytes increases significantly. In addition, our results suggest that in vivo environment could help improve the results of oocyte cryopreservation.

Observations on the right ovary of birds of prey: a histological and immunohistochemical study.

In most avian species, only the left ovary and oviduct are developed in the adult bird. Right ovaries and oviducts usually do not mature further after hatching and remain only rudimentary. However, occurrence of a functional right ovary is frequently found in several species of birds of prey. In this study, we investigated the occurrence of the right ovaries and their morphology in these bird species. Four examined wild bird species possessed a right ovary: long-eared owl, common buzzard, sparrow hawk and goshawk. We used histological and immunohistochemical techniques to evaluate structural differences of the gonads and tried to correlate the findings with folliculogenesis and endocrine functions. The right ovaries showed different sizes and shapes. Cytoskeletal elements (tubulin and vimentin) and α-smooth muscle actin have been detected in different structures of the right ovaries, but their staining intensity was weaker compared with the left ovary. This shows that also the right ovary is mechanically able to ovulate. We could also demonstrate the expression of oestrogen receptor α and progesterone receptor in the right ovaries, which indicates that also the right ovary can respond to steroid hormone stimuli. We assume that the expression of steroid hormone receptors in the presumptive gonad is still sufficient to mediate the development of a right ovary in the studied species. We conclude that the expression of steroid hormone receptors in the right ovary is involved in its post-natal development. The histological and immunohistochemical data also imply that in the right ovary, folliculogenesis and ovulation can occur.

Embryological basis of the virgin birth of Jesus

Virgin Mary gave birth to Jesus without a father. A scenario is presented here for this miraculous event. She is a chimera of 46,XX/46,XY type resulting from the fusion of two embryos of different sex types and both ovary and testis develop in Her body. It is well known that in chimera XX cells tend to gather on the left side while XY cells on the right; therefore, an ovary develops at the left side with an oviduct and a testis develops at the right side of the abdominal cavity with no duct. Both gonads are functional and produce oocyte and spermatozoa respectively after puberty. At the time of ovulation, estrogens leads to a negative pressure in the left oviduct and this vacuum effect helps oocyte and sperms to be picked-up into the tube, taking both types of gametes to the fertilization site in the left oviduct. Because of the higher temperature of the oocyte at the left ovary, fertilization occurs with a Y-bearing sperm to give rise to a XY male embryo which becomes miraculously Jesus.

Carcass Characteristics, Haematological Parameters and Reproductive Tract Morphometry of Rabbits Fed Cassava Leaf Meal

A 12 week feeding trial was conducted to evaluate the feed effect on carcass characteristics, haematological parameters and reproductive tract morphometry of female rabbits fed cassava leaf meal diets. The study was conducted at the University of Agriculture Makurdi, Livestock Teaching and Research Farm. Sixteen weaned rabbits (4 weeks old) were fed four diets in a completely randomised design experiment. Diet 1 contained no cassava leaf meal (CLM), while Diets 2, 3 and 4 has maize replaced with cassava leaf meal at 10, 20 and 30% CLM respectively. Haematological parameters of the rabbits did not show any significant difference between treatments. There was also no significant difference on the reproductive tract morphometry except on the length of the left oviduct and the weight of the vagina. Sun dried CLM has no adverse effect on carcass yield, visceral organ weight, haematological characteristics and reproductive tract morphometry of female rabbits. This suggests that sun dried cassava leave meal in diet to replace maize up to 30% can support visceral organ development, haematological characteristics and female reproductive tract development in rabbits. Further studies are necessary to determine the reproductive and growth performance of rabbits fed CLM diets at higher levels of replacement.

110 ASSISTED CONCEPTION IN THE FISHING CAT BY LAPAROSCOPIC INTRATUBAL INSEMINATION

Fishing cats (Prionailurus viverrinus) are small (6–15 kg) spotted cats from dispersed areas of Southeast Asia found mostly in wetland habitats. They are classified by the International Union for Conservation of Nature (IUCN) as endangered, with a decreasing population, due to habitat loss and degradation. Few studies have been done on applying assisted breeding techniques to the species, although the birth of a live kitten after IVF/embryo transfer (ET) has been reported (2006 Theriogenology 66, 1518–1524). Here, we describe the birth of a live fishing cat kitten using the technique of laparoscopic intratubal AI. A ten-year-old female who had served previously as an oocyte donor (5×) following gonadotropin treatment was administered a total of 5 IU of porcine FSH (Sioux Biochemical, Sioux City, Iowa) over 4 days (1×/day) followed by 10 IU of porcine LH on the fifth day. At approximately 28 h after LH treatment, the ovaries/oviduct were accessed by a laparoscopic technique comparable to that used for oviducal embryo transfer (ibid.). To deposit semen into the left oviduct, a 16-guage thin-wall trocar/needle was inserted into the abdominal cavity on the right side, approximately 1 cm lateral to the midline and approximately 2 to 3 cm below the umbilicus. A 14-cm open-end tom cat catheter was inserted into the 16-guage cannula (blunt) and the catheter tip was positioned underneath the fimbria overlaying the ovary. Then, a 50-mm length of 30-guage polytetrafluoroethylene (PTFE) thin-wall tubing containing approximately 30 μL of freshly collected semen was threaded through the catheter and the sample was expelled with positive pressure from a threaded-plunger 1-mL syringe. The left ovary contained 7 to 8 preovulatory (3–4 mm) follicles, 4 of which were manually ruptured immediately after deposition of semen with a 22-guage needle inserted through the 16-guage cannula. Then, with the 16-guage trocar/cannula in the same position (on the right side), the tip was redirected towards the right ovary and approximately 30 μL of semen was deposited underneath the fimbria as described above. The right ovary presented with 5 to 6 preovulatory (3–4 mm) follicles, 2 of which were punctured with the 22-guage needle after insemination. No ovulations were present on either ovary. The semen used for insemination was a fresh sample collected by electroejaculation from a 9-year-old male. The raw sperm concentration was 220 million mL–1, with 70% motility. The number of motile sperm deposited per oviduct was estimated to be approximately 4.6 million. The female was anesthetized 51 days later and radiography was done to determine her pregnancy status. A single fetus was present, so she was moved from an outdoor pen into a large indoor holding pen to allow for video-monitoring during the remainder of gestation. On Day 70, early signs of labour were observed and an elective Caesarean section was done approximately 4 h later. A live, healthy male kitten weighing 204 g was delivered. One year later, gonadotropin treatment/AI were repeated on the same pair. At approximately 30 h post-LH treatment, preovulatory follicles were present, but fewer than the previous treatment (5–6 total). Two fresh ovulation sites were seen on the left ovary. Pregnancy was not established. A reason for the failure was not apparent, unless it was age related.

Prefemoral Salpingotomy and Salpingoscopy in a Red-Eared Slider (Trachemys scripta elegans) with Pathologic Egg Retention

Abstract A 40-yr-old female red-eared slider (Trachemys scripta elegans) was presented for acute lethargy and anorexia of 48 h duration. A dorsoventral radiograph revealed a single hypercalcified egg within the left oviduct. Hematology and plasma biochemical values were considered normal for a gravid turtle. Administration of oxytocin failed to induce oviposition. Prefemoral salpingotomy with the aid of carbon dioxide laser facilitated removal of a necrotic egg after fragmentation of the egg in situ. Endoscopic examination of the lumen of the oviduct (salpingoscopy) through the salpingotomy incision provided direct visualization of oviductal mucosa, ruled out obstructive lesions, and confirmed complete removal of the egg and its contents. The turtle's appetite returned to normal 24 h after surgery.

Morphometric Dimentions of the Genitalia of Savanna Brown Goats between Day 24 and 30 Postpartum

This study was carried out to determine changes in ovarian and uterine dimensions in Savanna Brown (SB) goats between days 24 and 30 postpartum (pp). The mean (± sem) weight of the right ovary (ROV) was significantly higher (P 0.3 cm in diameter in the ROV was higher (P< 0.05) at day 30 pp than day 26 pp. Mean weight of FF from the left ovary (LOV) was heavier (P< 0.05) than from the ROV during the period of study. The inter-caruncular distance in both the right (Rh) and left (Lh) uterine horns was longer (P< 0.05) at day 30 pp. The left oviduct was longer (P <0.05) than the right oviduct at day 30 pp. It is concluded that pp ovarian follicle activity was higher in the ROV than LOV and inter-carunucular distance and left oviductal length were significantly longer between days 28 and 30 pp.

Anti-fertility effects of different fractions of Anethum graveolens L. extracts on female rats.

Our previous studies showed the effects of aqueous and ethanol extracts of Anethum graveolens L. (dill) on female infertility. In the present study we investigated whether different fractions of this herb extract can cause infertility in rats. Female rats were divided into the control groups, the groups receiving either a low (0.5 g/kg)) or a high dose (5g/kg) of water, N-butanol, chloroform and ether fractions of the aqueous plant extract, and the groups receiving either a low (0.045 g/kg) or a high dose (0.45 g/kg) of the same fractions of ethanol extract. The mentioned doses were gavaged in 1mL for 10 days. Vaginal smears were prepared daily. Estradiol and progesterone levels were measured. The left oviduct and ovary were removed, their tissue subsequently being prepared in form of histology slides and stained using haematoxylin-eosin and Masson's trichrome. Female rats assigned to each group were mated with males; after that, crown-rump lengths and weights of newborn rats were measured. Results showed that each fraction produced some changes such as hormonal level reduction (chloroform fraction), diestrus phase prolongation and infertility (water fraction), and increase in pregnancy duration (chloroform and ether fractions). We concluded that each fraction comprises only some of the mentioned components and therefore recommended the usage of crude extract, especially the aqueous one, in case infertility aims to be induced.

Pathology of Oviduct in Sub Optimally Producing Commercial Layer Chicken

Pathology of oviduct in sub optimally producing commercial layer chicken were investigated in five flocks. Suboptimal production was commonly noticed between 23rd to 45th wk of age. The production drop ranged from 5 to 12 per cent below the expected egg production. The morbidity and mortality rates varied from 5 to 11 and 0.2 to 2 percent, respectively. The antibody HI titres for NDV (128-445.7) IB (45.3-128) and EDS -76 (2 to 4) were within the normal range. ELISA titre for MG and MS was below 269. The heterophil : lymphocyte (H:L) ratio was above the normal level in all the five flocks and it was more elevated in younger (0.97) compared to older (0.63) flocks. Bacteriological and virological examination revealed no organisms of any etiological significance. Grossly, regression, deformation and loss of hierarchy in ovarian follicles were noticed. The left oviduct was, short, narrow and thread like structure in few birds and in the remaining cases partial atrophy with demarcation were noticed. On opening, the mucosal surface of the affected oviduct lost its glistening appearance and the folds were markedly reduced in height and width. Histopathologically, deciliation of surface epithelium, degeneration and involution of the glandular tissues with well developed connective tissue matrix and mild to moderate mononuclear cells infiltration in all the parts of oviduct were noticed. Absence of etiological agents and elevation of H:L ratio suggest that the atrophy of oviduct in sub optimally producing flocks may be due to non specific stress experienced by the commercial layer chickens.

Egg capsules of the little skate, Psammobatis extenta (Garman, 1913) (Chondrichthyes, Rajidae)

Corresponding author: rochaf_bio@yahoo.com.br The elasmobranch Rajidae family, known usually as skates, is the most numerous group among cartilaginous fishes, having almost 245 species with very conservative morphology (EBERT and COMPAGNO, 2007). Elasmobranch egg capsules are widely recognised as important in species identification and provide relevant information concerning their reproductive biology (ODDONE et al. , 2004). The genus Psammobatis GUNTHER, 1870 comprises eight species, four of them recorded in Brazil (PARAGO, 2001): P. extenta (GARMAN, 1913), P. rutrum JORDAN, 1890, P. bergi MARINI, 1932, and P. lentiginosa (BIGELOW and SCHROEDER, 1953). Psammobatis extenta , the little skate, is endemic to the continental shelf of the western South Atlantic, ranging from Cabo Frio, Rio de Janeiro, Brazil (22°56’S) to Patagonia, Argentina (~ 45°S) (PARAGO, 2001). Recent studies of P. extenta have focused mainly on its reproduction, morphology and feeding habits (BRACCINI and PEREZ, 2005; BRACCINI and CHIARAMONTE, 2002a; 2002b) and detailed information concerning its egg capsules is lacking. Only the egg capsules of P. scobina (PHILIPPI, 1857), from the Southeastern Pacific, have been accurately described (CONCHA et al. , 2009); short descriptions of the egg capsules of P. rudis , P. normani and P. bergi have been presented with their reproductive biology (MABRAGANA and COUSSEAU, 2004 and SAN MARTIN et al. , 2005). The present study describes the egg capsules of Psammobatis extenta , a small common rajid species of the western South Atlantic. Sixty-one egg capsules were removed directly from the 35 female Psammobatis extenta oviduct, thus avoiding species misidentification. The females were collected by bottom trawlers on the Sao Paulo continental shelf, at 30 to 50 m depths (between 24°12’S; 46°04’ W and 24°08’S; 46°50’W), during 2002, except in autumn. The general morphology, color, texture, presence and number of eggs, presence and position of attachment fibrils, presence and shape of velum and keel and finally, presence, position and shape of ventilation fissures were all recorded. The measurements taken were: capsule length (without horns), maximum width, anterior and posterior horn lengths, capsule height, and thickness and width of lateral keel. Both the terminology and morphometrics follow TEMPLEMAN (1982), ODDONE et al. (2004) and TREOLAR et al. (2006). Only fully developed capsules were used in the calculations made and the terms ‘anterior’/‘posterior’ and ‘dorsal’/‘ventral’ refer to the position of the egg capsules in the female oviduct (TEMPLEMAN, 1982). Capsules were fixed in formalin and preserved in 70% ethanol. The total length of the females was measured from the tip of the snout to the tip of the tail. Differences between anterior and posterior horn lengths and between right and left egg capsules were verified with Student´s t-test and the relationship between the females´ total length and the body length of the capsules was investigated by linear regression (SOKAL and ROHLF, 1995). The capsule measurements are presented in Table 1. Only one egg capsule was found in each female’s oviduct and just one egg was found per capsule. Almost 75% of the gravid females had capsules in both oviducts and when only one capsule was present, it was in the left oviduct (except for one female, which had developing horns on the right shell gland). The fully developed egg capsules are rectangular, with a horny process on each corner and a brownish copper in color (Fig. 1). The capsule walls are symmetrically convex, with the highest point situated centrally. Both capsule walls present a

Evaluation of the impact of in-ovo exposure to dicofol on avian reproduction

To assess the possible impact of the currently used organochlorine insecticide, dicofol, on the development and reproduction of avian species, in ovo exposure experiments to its p,p' and o,p' isomers were performed using Japanese quail (Coturnix japonica) eggs. o,p'-Dicofol (0.3-100 µg/g of egg) and p,p'-dicofol (3-100 µg/g) were injected into the yolk prior to incubation and hatched chicks were raised to adulthood. In ovo treatment with o,p'-dicofol impaired the eggshell-forming ability of female quails after sexual maturity; eggshell strength, mass, and thickness were significantly reduced at minimum dosages of 3, 1, and 0.3 µg/g, respectively. o,p'-Dicofol also caused abnormal development of the right oviduct independently of the dose; even a female exposed at the lowest dose tested (0.3 µg/g) possessed a large right oviduct. Minor but significant mass reductions of both the left oviduct and the testis were observed only at 10 µg/g. In addition, the transcript of a gene encoding cytochrome P450 cholesterol side-chain cleavage in the gonads of male hatchlings was markedly reduced by o,p'-dicofol treatment. p,p'-Dicofol did not have any marked effects on the reproductive systems, although some significant changes in eggshell formation and oviduct morphology were observed. The results indicate that transovarian exposure, especially to o,p'-dicofol, could damage avian reproduction mainly through eggshell thinning.

Atresia of the Left Oviduct and Abnormality of the Caecum of a 12-month-old Layer:A Case Report

Atresia of the Left Oviduct and Abnormality of the Caecum of a 12-month-old Layer:A Case Report

Case Report: Atresia of the Left Oviduct and Anormaly of the Caecum of a 12 Month Old Layer

Case Report: Atresia of the Left Oviduct and Anormaly of the Caecum of a 12 Month Old Layer

In vivo development of vitrified rabbit embryos: Effects on prenatal survival and placental development

The aim of this work is to study the effect of the vitrification procedure on prenatal survival and on placental development at the end of gestation in rabbits (Oryctolagus cuniculus). One hundred eighty-one females were slaughtered at 72 h of gestation. Morphologically normal embryos recovered at 72 h of gestation were kept at room temperature until transfer or vitrification. Vitrified embryos (320 embryos) were transferred into a total of 24 does and fresh embryos (712 embryos) were transferred into a total of 43 does. Females were induced to ovulate 72 h before transfer when fresh embryos were transferred and 60 to 63 h before transfer when vitrified embryos were transferred. Each recipient doe received eight embryos into the left oviduct and eight embryos into the right oviduct. The number of implanted embryos was estimated by laparoscopy as number of implantation sites at Day 14 of gestation. Recipient females were slaughtered by stunning and exsanguination 25 d after the transfer, and fetuses were classified according to their status. Live fetuses and fetal and maternal placenta were weighed Pregnancy rate was defined as the total number of females having at least one live fetus at Day 28 of gestation divided by the total number of females. Prenatal survival was estimated as live fetuses at Day 28 of gestation divided by the number of transferred embryos. The pregnancy rate after transfer of vitrified embryos (92%) was similar to that achieved with fresh embryos (86%), but prenatal survival was lower for vitrified than for fresh embryos (53% vs. 34%). We did not find differences in embryo survival from 72 h to implantation. Transfer of vitrified embryos reduced fetal survival from implantation to Day 28 (57% vs. 82%). Differences in the number of live fetuses at Day 28 of gestation were mainly due to the higher fetal mortality observed soon after implantation in pregnancies resulting from the transfer of vitrified embryos. A higher percentage of decidual reactions and atrophic maternal placentas (27.5% vs. 8.3%) and also of atrophic fetal and maternal placentas (12.1% vs. 5.3%) were observed after transfer of vitrified embryos. Both treatments showed similar percentage of dead fetuses (3.3% vs. 4%). Maternal placenta of the fetuses from fresh embryos was 15% heavier than maternal placenta of fetuses from vitrified embryos.

Light, Scanning and Transmission Electron Microscopical Study on the Oviduct of the Ostrich (Struthio camelus)

Nine mature female ostriches (Struthio camelus) aged 37- 49 months were used for the present study. The samples were taken during the period from September to November from Almasreya ostrich farm, immediately after sacrification and evisceration. Pieces from the different segments of the left oviduct were taken, then fixed in 10% neutral buffered formalin and Bouin’s and Susa solutions for the light microscopic study and in 2 % gluteraldehyde for both scanning and transmission E/M examination. For light microscopic study the slides were stained with Harri's hematoxylen and eosin, Crossman’s trichrome stain, Weigert's elastic tissue stain and Periodic acid Schiff technique (PAS).The right oviduct is rudimentary, while the left one is well developed and is formed of five segments, namely: infundibulum, magnum, isthmus, uterus, and vagina. The scanning E/M revealed that the lining epithelium of the oviduct is folded and formed of pseudostratified columnar ciliated cells. The cilia were slender, dense uniformly arranged, and identical in length. In magnum, isthmus and uterus the scanning E/M study revealed the presence of openings between the cilia for the secretion of the tubular glands of the lamina propria.

Reproductive and developmental effects of transovarian exposure to o,p′‐DDT in Japanese quails

Avian species have the possible risk of embryonic exposure to persistent, lipophilic environmental contaminants, such as dichlorodiphenyltrichloroethane (DDT), by transfer of chemicals accumulated in mother birds to eggs. To model developmental and reproductive disorders of wild birds living in contaminated areas, we exposed Japanese quails in ovo to o,p'-DDT prior to incubation. A positive estrogenic substance diethylstilbestrol (DES; 1 and 10 ng/g of egg) and o,p'-DDT (1-100 microg/g of egg) were injected into the yolk before incubation. Treatment with o,p'-DDT (10 or 100 microg/g) but not with DES significantly reduced the hatchability of eggs. After sexual maturation, o,p'-DDT affected eggshell formation in female quails but had little influence on laying; high doses of o,p'-DDT significantly reduced eggshell strength, shell weight, and shell thickness, and several females treated with 100 microg o,p'-DDT/g laid eggs lacking shells. Diethylstilbestrol decreased egg production itself but had little effect on the eggshell. Both o,p'-DDT and DES caused dose-dependent shortening of the left oviduct and abnormal development of the right oviduct in females, while testis asymmetry was observed in males treated with a high dose of DES. In the uterus of the oviduct, the mRNAs for calcium-regulating factors osteopontin and calbindin D28K were reduced by both treatments, particularly that with o,p'-DDT. The results indicated that transovarian exposure to o,p'-DDT could bring about population declines in avian species through loss of fecundity caused by depression of hatchability and dysfunction of the reproductive tract.

Macroscopic and Microscopic Anatomy of the Oviduct in the Sexually Mature Rhea (Rhea americana)

The morphological characteristics of the oviduct of 12 sexually mature rheas (Rhea americana) were studied. Only the left oviduct is developed as a long tube with a length of 122 +/- 23.1 cm, and is subdivided into infundibulum (15.2 +/- 4.0 cm), magnum (63.3 +/- 9.4 cm), isthmus (5.6 +/- 3.1 cm), uterus (16.0 +/- 4.2 cm) and vagina (11.5 +/- 1.4 cm). The mucous membrane of the oviduct, as a whole, possesses luminal folds covered by ciliated columnar epithelium with secretory cells. The infundibulum part presents a cranial opening with thin and long fimbriae with few tubular glands in caudal tubular portion. In the magnum, the largest portion of the oviduct, the folds are thicker and are filled with tubular glands. The isthmus is short and presents less bulky folds and a few tubular glands. A bag-shaped uterus in the cranial area shows thin folds, and in the caudal region (shell gland) more ramified folds with few tubular glands. The vagina has long luminal folds and a thick muscular tunic; no glands with sperm-storage characteristics have been observed. In conclusion, the oviduct in sexually mature rhea has morphological similarities with the other species of birds already described; however it presents its own characteristics to produce a big egg.