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1.
A case of disrupted embryonic development of the genital tract in a newborn Holstein calf is described. The physical examination of the calf evidenced several abnormalities, like atresia ani, rudimentary external genitalia and caudal vertebral agenesis. On necropsy, the excised genitalia consisted of bilateral streak gonads, apparently normal uterine tubes, a fluid-filled uterus, a long vagina and a very narrow clitoris-like structure covered with a discrete skin-fold. The urinary tract seemed normal and the urethra's opening was at the vestibule-vaginal junction. A cytogenetic analysis was requested. Karyotype revealed the existence of Y chromosome material in the two X chromosomes. However, the search for the sex-determining region Y (SRY) showed that this was an apparently absent gene. The histological examination of the gonads revealed the existence of ovarian dysplasia. Uterine sections evidenced the absence of the uterine epithelium, with only sporadic caruncles. Under microscopic examination, the uterine tubes and vagina structure was normal. The external genitalia sections revealed the existence of a skin-fold covering an erectile structure surrounding the urethra, a structure more similar to a penis than to a clitoris. This is an unusual situation of gonadal dysplasia combined with genital tract anomalies in cattle, probably associated to a genetic defect.  相似文献   

2.
An unusual case of a live Holstein freemartin calf co-twinned with schistosomus reflexus fetus is presented here. Delivery of the schistosomus reflexus was achieved by fetotomy 24 h after manual delivery of a live heifer calf. The dam subsequently experienced concurrent metritis and left displacement of the abomasum; however, she conceived following insemination 85 d post partum. Cytogenetic examination of the live heifer using lymphocyte culture and cutaneous fibroblast cell culture failed to demonstrate chromosomal chimerism, whereas polymerase chain reaction (PCR) detected the presence of the bovine Y-chromosome marker BRY-1. Low concentrations of testosterone, estradiol and progesterone at 3, 6, 24 and 48 h after administration of hCG were detected in the serum of the freemartin heifer. Genetic, hormonal, histological and clinical findings established the live female co-twin calf was a freemartin, an abnormality of phenotypic sex. Failure to detect any significant peripheral concentrations of androgen supports the hypothesis that masculinization of the freemartin reproductive tract arises from diffusion of androgen and possibly other substances from the male co-twin rather than from endogenous production of androgen within the freemartin. This report documents that the freemartin condition can be induced by a male fetus with severe developmental abnormalities.  相似文献   

3.
The effect of photoperiod on sexual function and growth in weanling male and female collared lemmings (Dicrostonyx groenlandicus) was studied. Males and females maintained in 6 hr light:18 hr dark after weaning were larger at the end of 70 days than their siblings kept in 20L:4D. Males in 6L:18D were longer and overall body growth was greater. Males in 6L:18D had heavier adrenals but there were no differences in the weights of testes, preputial glands or seminal vesicles or in the mean testosterone levels of the two groups. Females in 6L:18D had heavier preputial glands than the 20L:4D females. There were no differences between the two groups in uterine, ovarian or adrenal weights or in the number or mean size of atretic or healthy Graafian follicles. Adult males kept in 6L:18D increased more in body weight than those in 20L:4D, but there was no detectable influence of the short photoperiod on reproductive function.  相似文献   

4.
Male pseudohermaphroditism is a sex differentiation disorder in which the gonads are testes and the genital ducts are incompletely masculinized. An 8 years old dog with normal male karyotype was referred for examination of external genitalia abnormalities. Adjacent to the vulva subcutaneous undescended testes were observed. The histology of the gonads revealed a Leydig and Sertoli cell neoplasia. The contemporaneous presence of testicular tissue, vulva, male karyotype were compatible with a male pseudohermaphrodite (MPH) condition.  相似文献   

5.
Induction of twinning by ipsilateral nonsurgical transfer of two frozen-thawed Japanese Black bovine embryos to each of 20 Holstein and 26 Japanese Black cows, that had been kept under a stable in private farm conditions, was examined. The cows were monitored every 20 days from Day 25 to Day 65 of gestation for pregnancy and fetus survival (estrus is Day 0). Seventy-five per cent (15 of 20), 65.0% (13 of 20) or 60.0% (12 of 20) and 61.5% (16 of 26), 53.8% (14 of 26) or 50.0% (13 of 26) of Japanese Black cows were diagnosed pregnant at 25, 45 and 65 days after transfer by ultrasonic echography. Embryonic losses were observed between Days 25 and 65 in 29.2% (7) Holstein and 31.8% (7) Japanese Black cows. The twin pregnancy rate in Holstein and Japanese Black cows decreased with time; 60.0% (9 of 15) vs. 37.5% (6 of 16) at Day 25; 53.8% (7 of 13) vs. 28.6% (4 of 14) at Day 45 and 41.7% (5 of 12) vs. 15.4% (2 of 13) at Day 65. At calving, Holstein cows produced five sets of twins and seven single calves, and Japanese Black cows two sets of twins and 11 single calves. The twinning rate in Holstein cows was higher (P < 0.05) than that in Japanese Black cows, 41.7% (5 of 12) vs. 15.4% (2 of 13). The calf birth weight in Holsteins was heavier (P < 0.05) than that in Japanese Black dams (24.5 kg, 33.6 kg vs. 19.3 kg, 25.5 kg for twin and single calves). The placental weight in Holstein dams calving twins was heavier than that in Holstein dams calving a single calf or in Japanese Black dams calving either twins or a single calf (6.6 kg vs. 3.5 kg, 4.6 kg or 2.8 kg). The number of placentome in Holstein dams calving twins was also higher (P < 0.05) than that in Holstein dams calving a single calf or Japanese Black dams (103.5 vs. 41.8, 67.9, 33.0). The number of placentome was approximately double in dams calving twins than that of dams calving a single calf.  相似文献   

6.
The relationship between the quantity of seminal vesicle secretion in the ejaculate, the percentage of spermatozoa reaching the uterus and fertility was studied in rats. Different portions of seminal vesicles were removed from male rats; 15 min after coitus (day 0), the numbers of spermatozoa in the uterus and vagina were counted and the vaginal plug characteristics were noted. Fertility was evaluated by the number of fetuses on day 14. A gradual decrease in the percentage of spermatozoa in the uterus was positively related to the reduction in seminal vesicle secretion, estimated by plug weight. This decline was not caused by a delay in sperm transport to the uterine lumen and the results suggested that the spermatozoa that fail to enter the uterus in the first minutes after coitus never enter. The vaginal plug weight, which is related to the seminal vesicle weight, and the position of the plug, which must be firmly lodged into the cervical opening, seem to be the most important conditions for promoting the rapid passage of spermatozoa into the uterus. When the seminal vesicles were partially removed, the plug was not tightly lodged and formed a 'cup' filled with spermatozoa. The number of fetuses did not show a close correlation with the quantity of seminal vesicle secretion. Studies of males in which the seminal vesicles had been removed indicated that a normal number of fetuses can be obtained despite low numbers of spermatozoa reaching the uterus. Ablation of the coagulating glands showed that, when there is no vaginal plug, no spermatozoa reach the uterus and fertility is suppressed. Nevertheless, the complete removal of coagulating glands is difficult; when small portions of these glands remain, the vaginal plug is formed and then fertility is achieved.  相似文献   

7.
To confirm the normality of the Japanese Black calves produced by nuclear transfer, we examined the properties of such calves at parturition and analyzed their karyotypes. Thirty Japanese Black calves were produced by nuclear transfer; 3 of these calves (10.0%) required assisted delivery while 1 calf (3.3%) died soon after birth. Average birth weight was 31.0 +/- 1.8 kg and gestation period was 286.4 +/- 1.0 d (mean +/- SEM). None of the nuclear transfer calves showed external malformations. Within sets of cloned nuclear transfer calves, which were genetically identical, birth weights varied by up to 20.5 kg. Among singleton Japanese Black calves, the mean birth weight of nuclear transfer calves was significantly greater (P < 0.05) than that of calves produced by in vivo-derived embryo transfer. Cytogenetic analysis of 23 Japanese Black nuclear transfer calves revealed the presence of 2N 4N mosaicism in 21 of the nuclear transfer calves. The frequency of occurrence of tetraploidy was unrelated to birth weight. Endoreduplication was observed in 1 Japanese Black nuclear transfer calf, and the frequency of occurrence of the endoreduplication in this calf was 0.5% (1/209). We conclude that there was no external malformation or chromosomal aneuploidy in Japanese Black nuclear transfer calves, but the mean birth weight of nuclear transfer calves was heavier than that of in vivo-derived embryo transfer calves in both sexes, and a variation of birth weight within sets of nuclear transfer calves cloned from the same embryo was recognized.  相似文献   

8.
A new genus and species of tetradonematid nematode, Myrmeconema neotropicum n. g., n. sp., is described from larval, pupal and adult stages of Cephalotes atratus L. (Hymenoptera: Formicidae) in Peru and Panama. Diagnostic characters of the new genus include: males and females subequal in size; cuticle with minute annulations; six cephalic papillae; stylet present in all stages; stichocytes absent; trophosome degenerate; three penetration glands; gonads paired and opposite; vulva in mid-body region; single spicule; genital papillae absent; adult tails rounded; infective juveniles moult once in egg; and adults of both sexes remain in the host throughout their development. As the female nematodes mature inside the worker ants, the host gasters change colour from black to red.  相似文献   

9.
G W Hinsch 《Teratology》1979,20(3):463-468
A litter of five salukis was presented in which all of the individuals were intersexes or hermaphrodites. Anatomical abnormalities were observed. The external genitalia resembled a combination of penile sheath and vulva positioned approximately midway between the anus and umbilicus. At birth structures resembling scrotal sacs were present on either side of the genital structure. These were not apparent in older animals. Internal anatomy consisted of two gonads in a position expected for ovaries, oviducts, uterus and cord-like structures lateral to the uterus which extended from gonad to inside of the "scrotal sacs." Histologically, the gonads appeared to be ovaries which contained many dysgenic follicles. Cause of the condition is unknown.  相似文献   

10.
Summary The name Deurithitrema gingae n. g., n. sp. is proposed for worms from the kidneys of one Crocodylus porosus from Darwin, Northern Territory, Australia. The following combination of characters distinguishes the new genus from all others: prepharynx very short; oesophagus absent; caeca reaching to posterior end of body; testes tandem in middle third of body, contiguous or amost so; cirrus-sac large, over-reaches ventral sucker, contains bipartite seminal vesicle, prostatic regions and ejaculatory duct with spines around its opening into genital atrium; genital pore immediately in front of ventral sucker; uterus coiled to posterior end of body; vitellaria lateral from ventral sucker to slightly behind testes; excretory vesicle small, receiving a single ventro-lateral duct from each side behind end of uterine loops. Deurithitrema belongs to the superfamily Plagiorchioidea Dollfus, 1930. It superficially resembles a number of genera, but its relationships within the superfamily are obscure.  相似文献   

11.
The relative significance of the accessory glands of the male reproductive tract in fertility is unclear. To clarify the role of the seminal vesicles, fertility and uterine sperm motility were determined before and after removal of seminal vesicles in the house mouse. After removal of seminal vesicles, the pregnancy rate (number of females pregnant/number of females X 100) was reduced and the time to birth was increased, while the average litter size was not changed. Fertilization, determined by examining the oocytes 30 h after mating, was highly variable after matings with males whose seminal vesicles were removed; in some cases none of the oocytes were fertilized. The motility of sperm recovered from the uterus 1 h after matings with males before and after seminal vesicle removal and sham operations was analyzed using a videomicrographic system. The motility of uterine sperm was less progressive with more lateral displacement of the head about the trajectory and a less linear trajectory after removal of the seminal vesicles. Sham-operated animals showed no consistent changes in motility of uterine sperm. The changes in sperm motility could contribute to the reduction in fertilization since sperm motility is necessary for transport in the female reproductive tract and interaction with the oocytes.  相似文献   

12.
To establish the polymerase chain reaction (PCR) method for detecting the XY cells in cases suspected to have the bovine freemartin syndrome, a PCR reaction test was conducted on blood from a normal bull diluted in blood from a normal cow. From the results obtained, it was shown that the Y-specific sequence was detectable down to a concentration of 0.1%. Various types of the bovine freemartin syndrome, which occurs in heterosexual twins, single-born sterile heifers, and heifers born with Acardius amorphus, were examined by the chromosome analysis and the PCR method. The Y-specific sequence was detected in all 26 cases that showed chromosome chimerism but which was absent in the 5 cases without a chimerism. The PCR method was found to be effective and convenient for quickly diagnosing the various types of bovine freemartin syndrome.  相似文献   

13.
In a low dose and short chronic exposure, Sonatox (2,2,5-endo, 6-exo-8,9,10-heptachloroborane), a chlorinated insecticide, impaired ovarian activity in the fish Oreochromis mossambicus. The histological profile showed abnormalities of the different kinds of oocytes and their nuclei. Compared with the controls, a sharp drop in the proportion and diameter of the various oocytes was observed. Fish exposed to Sonatox had more atretic oocytes than were found in the controls. Percentual gonad weight in relation to body weight was also significantly reduced in treated fish (p less than 0.001). These changes are indicative of regression of the gonads after exposure to the insecticide.  相似文献   

14.
The hormonal functions of suprarenal glands and gonads were studied in the sacred baboon males and females during different periods of postnatal development. This in view, the content of cortisol, 11-deoxycortisol, pregnenolone, progesterone, 17-oxypregnenolone, 17-oxyprogesterone, 20 alpha-dihydroprogesterone, estrone and estradiol was determined using the radioimmunoassay. The early activation of secretion of the suprarenal androgens, characteristic of the man, is absent during the sexual maturation of the sacred baboon males and females. The level of corticosteroids and their basic precursors, characteristic of the adult sacred baboons, is extablished by the end of 3rd year of life.  相似文献   

15.
To determine whether anti-Müllerian hormone (AMH) is responsible for the gonadal lesions observed in bovine genetic females united by placental anastomoses to male twins (freemartins), prospective ovaries of fetal rats were exposed to purified bovine AMH in vitro. In cultures initiated at 14 days p.c. and maintained 3 to 10 days, AMH consistently induced a characteristic 'freemartin effect', namely reduction of gonadal volume, germ cell depletion and differentiation, in the gonadal blastema, of epithelial cells with large clear cytoplasm linked by interdigitations, resembling rat fetal Sertoli cells. These cells tend to become polarized and form cords, delineated by a continuous basal membrane containing laminin and fibronectin. Such structures, resembling developing seminiferous cords, were not detected in control ovarian cultures. These data strongly suggest that AMH is the testicular factor responsible for triggering the morphological abnormalities of freemartin gonads.  相似文献   

16.
The gonad of the protogynous, hermaphroditic teleost, Monopterus albus were examined histologically at monthly intervals throughout one year. In particular, the epithelium of the maturing follicles of the female and the atretic follicles in the female, intersex and male were studied. Atretic follicles were common in the gonads and were classified as corpora atretica types 1 to 5 according to histological criteria. In addition, other regressive structures were observed in the gonads of some males. The histology and the frequency of occurrence of the atretic structures in the three sexual phases is described and discussed.  相似文献   

17.
江豚(Neophocaena asiaeorientalis)的消化器官Ⅱ. 肠、肝、胰   总被引:2,自引:2,他引:0  
本篇为江豚(Neophocaena asiaeorientalis)消化器官研究的第二部分。 标本来源见李悦民(1984)。肠的长度和肝的重量都由新鲜标本测得。组织学材料用10%甲醛溶液固定,石蜡包埋,切片用苏木精曙红,PAS和Van Gieson法染色。  相似文献   

18.
Cystic endometrial hyperplasia (CEH) is a uterine disorder characterized by the formation of large numbers of cysts in the endometrium. The purpose of this study was to examine and characterize cell types in the endometrium associated with the cysts and uterine glands. No apparent histological differences between CEH-involved and normal uterine columnar epithelium were found. Endometrial glands in CEH-involved and normal uteri were lined with simple or ciliated columnar epithelial cells and surrounded by lamellar connective tissue. The cyst epithelium appeared to be stretched obliquely and compressed so that both the cells and nuclei were horizontally oriented relative to the cyst lumen and were surrounded by lamellar connective tissue. Electron microgaphs revealed an abnormally high number of mitochondria in the cystic cells as compared to normal glandular cells. In conclusion, CEH is characterized by the formation of cysts which develop from the uterine glandular tissue. Epithelial cells lining the glands appeared to be distorted, possibly in response to internal pressure from increased volume due to high metabolic activity, and/or no uterine luminal opening.  相似文献   

19.
Reproduction of the fish Gymnothorax equatorialis (Pisces: Muraenidae) in Jalisco and Colima, Mexico. A total of 707 Gymnothorax equatorialis were collected monthly in the Jalisco and Colima coast, Mexico, from December 1995 to December 1998 and from August to November 1999, in order to determine their reproduction patterns. Females outnumbered and had longer bodies (mean length 54.7 cm) than males (52.1 cm). The minimum, maximum and mean values of total fecundity were respectively 9 660, 99 992 and 32 029 eggs. The total body length at which 50 percent of individuals have ripe gonads (L50) was 43.7 cm for females and 42.7 cm TL for males. Ovaries had two main types of oocytes: small inmature in cromatin nucleolus phase (85.1 microm) and large mature in secundary vitellogenesis phase (701.6 microm). High numbers of spermatozoa were observed in the seminal tubes of ripe testicles, which presented a lobular development. Based in gonad features and temporal changes in the gonad-somatic index, it is concluded that G. equatorialis has two relatively short reproduction periods (at the middle and at the end of the year).  相似文献   

20.
Male peacock blennies (Salaria pavo) release odors from their anal glands and, possibly, from their gonads that attract reproductive females. The current study investigated the effects of 11-ketotestosterone (KT) on development of the anal glands, testes, and accessory testicular organs as well as the subsequent olfactory potency of their secretions. After 3 wk of KT treatment (5 mg/kg in silastic implants), clusters of cells secreting neutral mucins differentiated in the anal gland of all treated males, whereas this occurred in only one control male. Secretions by anal glands from KT-treated males elicited greater olfactory responses, as assessed by electro-olfactography, than those from controls. Treatment with KT stimulated testicular gland growth and sialomucin secretion but had no clear effect on the germinal region of the testis; KT also stimulated enlargement of, and fluid secretion in, the blind pouches (paired evaginations of the spermatic ducts). Secretions by the testes and fluid in blind pouches from KT-treated males elicited greater olfactory responses than those from controls. In conclusion, KT stimulates development of the anal glands and testicular accessory organs and promotes odorant secretion, the putative multicomponent male peacock blenny pheromone.  相似文献   

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