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Establishment of assisted reproduction technologies in female and male African wild dogs (Lycaon pictus).

Transrectal ultrasonography, electroejaculation and cryopreservation of spermatozoa were applied to the African wild dog (Lycaon pictus) to establish non-invasive protocols for assessing the reproductive health of one of the most endangered African canids. Transrectal ultrasonography was performed on immobilized male (n = 2) and female (n = 5) captive wild dogs. The testes and epididymides of the male dogs were imaged transcutaneously, followed by electrostimulation and cryopreservation of spermatozoa. The sonomorphology of the female and male urogenital tracts was characterized. In females, the vagina, cervix, non-pregnant uterus and ovary were imaged and the reproductive health of each female was evaluated. The sonographic assessment helped to identify one pyometra and extensive abdominal fat deposits in two other individuals in which pyometra had been suspected. Images of the adrenal glands showed differences in size among individuals of the same breeding group. Whether these differences were related to the dominance hierarchy remains to be determined. In males, visualization of the prostate gland, testis and epididymis indicated sexual maturity. Three ejaculatory fractions (1.0, 1.5 and 0.5 ml, with 50, 95 and 95% motility, respectively; 1.125 x 10(8) spermatozoa per ejaculate) were collected from one male. The motility of each of these fractions after thawing was 0, 30 and 40%, respectively. Electrostimulation of the second male, in which a cystic structure in a testis had been identified by sonography, resulted in an aspermic ejaculate (0.5 and 1.0 ml). These technologies provided basic data on reproduction in female and male African wild dogs and were an efficient way to evaluate reproductive health.

Adrenal Glands↗

Reproductive technology in animal production.

Research into physiology and embryology has provided a basis for the development of technologies that increase productivity of farm animals through enhanced control of reproductive function. Progestagens, alone or in combination with luteolysins, are used to control the time of oestrus in cattle, sheep and pigs, thus permitting better use of artificial insemination, providing synchronised recipients for embryos and facilitating management strategies. Treatment with progestagens and pregnant mare serum gonadotrophin (PMSG) or with gonadotrophin releasing hormone induces breeding activity in sheep and goats before the commencement of the breeding season and reduces the duration of postpartum anoestrus in cattle. In pigs, gonadotrophins are used to hasten puberty in gilts, control the time of oestrus in sows and gilts and reduce the interval between farrowing and oestrus. Implants of melatonin hasten the onset of the breeding season in sheep and goats. Success in increasing litter size in sheep and cattle with PMSG has been limited because of the large variation in response between animals. Likewise, immunisation against steroids has not given consistent results. Immunisation against inhibin appears to offer the possibility of increasing farm animal fecundity. Induction of twinning in cattle by embryo transfer is practicable, and recent developments suggest that in vitro fertilisation may provide a source of embryos for this purpose. Real-time ultrasonic scanning has proved to be a reliable method for diagnosing pregnancy in small ruminants and pigs. The identification of pregnancy-specific proteins in cattle and sheep may provide a cheap and practical serological test for pregnancy in these species. Partial segregation of spermatozoa into X- and Y-bearing components has been reported, but the method is not yet practicable for use in conventional artificial insemination of farm animals. The sex of bovine and ovine embryos can be determined reliably by DNA probes specific for the Y chromosome. Monozygous twins can be produced in all farm animal species by microsurgical bisection of embryos and techniques for cloning from embryonic cells are rapidly being developed. There is a need to devise strategies to utilise these clones to best advantage in genetic programmes. Chimeric animals can be produced in the common farm animal species and will play an important role in genetic engineering, particularly when embryonic stem cell lines are produced in these species.

Animal Husbandry↗

Nuchal translucency in pregnancies conceived after assisted reproduction technology.

OBJECTIVES: Levels of maternal serum markers of fetal Down syndrome in pregnancies conceived after assisted reproduction are different from those of normal spontaneous pregnancies. The present study examined the effects of conventional in-vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI) and embryo cryopreservation on nuchal translucency (NT) thickness. METHODS: A retrospective analysis on 16 673 spontaneous pregnancies, 119 pregnancies with fresh embryos from IVF, 62 pregnancies with frozen-thawed embryos from IVF, 81 pregnancies with fresh embryos from ICSI and 39 frozen-thawed embryos from ICSI was performed. All were singletons with known normal outcomes. Multiples of the median (MoM) of NT were compared. RESULTS: The median NT MoM of spontaneous pregnancies was 1.01. In the assisted reproduction pregnancies, the median NT MoM were significantly increased to 1.07 (P = 0.003), 1.09 (P = 0.009) and 1.09 (P = 0.001) in pregnancies conceived with fresh embryos from IVF, frozen-thawed embryos from IVF and fresh embryos from ICSI, respectively. A non-significant increase in median NT MoM (1.04; P = 0.489) was also observed in pregnancies with frozen-thawed embryos from ICSI. CONCLUSIONS: Increased NT in assisted reproduction pregnancies is postulated to be due to some delay in fetal development. Another possible reason might be related to adverse antenatal course in these pregnancies.

Case-Control Studies↗

Possible applications of lasers in assisted reproductive technologies.

Laser systems seem to be the most promising technical tools to be introduced in assisted reproduction treatment in recent years. The 1.48 microm diode laser in particular is on course to supersede conventional mechanical and chemical methods for opening the zona pellucida in assisted hatching, and for biopsy of polar bodies or blastomeres. This is because it works without physically touching the cells, has no traceable toxic effects on living cells and is easy to handle. There will be manifold future possibilities for micromanipulation with lasers, as already demonstrated by the immobilization of spermatozoa prior to intracytoplasmic sperm injection, and the successful dissection of the zona pellucida into two halves with equal diameter for the hemizona assay.

Animals↗

Community attitudes to maternal age and pregnancy after assisted reproductive technology: too old at 50 years?

Community attitudes toward oocyte and embryo donation, and toward assisted reproduction after the menopause were assessed in this survey of 1131 Australians. Of the respondents, 64.2% believed that oocyte or embryo donation was an acceptable treatment for infertile couples, 54.6% felt that it was acceptable for a woman to have her own embryos transferred after the menopause, and 37.9% are accepting of the donation of eggs or embryos to post-menopausal women. There were no significant differences in response amongst different religious groups, or in relation to gender or income level. Significantly higher levels of acceptance were noted for all categories amongst those respondents aged < 35 years. Despite the established clinical ability to achieve pregnancy in the over 50 years age group, this survey reveals only minority community support for this practice. However, public opinion may alter in the future if the attitudes of the younger proportion of the sample are maintained.

Adolescent↗

Assisted reproductive technologies: toward improving implantation rates and reducing high-order multiple gestations.

Despite striking progress in reproductive medicine over the past quarter century, the number of high-order multiple gestations are unacceptably high, largely as a result of the drive to maintain pregnancy rates in a competitive range. Morphologic criteria are currently used to define the reproductive competence of individual embryos but are imperfect predictors of implantation potential. Current and potential strategies to improve the selection of embryos are described. By the use of several of these approaches, it is hoped that the overall number of embryos that are transferred will be reduced, thereby also reducing the multiple gestation rate.

Embryo Implantation↗

Assisted reproduction technology in Queen Mary Hospital: ten years' experience.

PURPOSE: To review the experience of an assisted reproduction program. DATA SOURCES: Department of Obstetrics and Gynaecology, University of Hong Kong. STUDY SELECTION: Assisted reproduction in a tertiary referral centre. DATA EXTRACTION: Results of assisted reproduction from 1986-1996. RESULTS: In the past ten years, 1561 treatment cycles of in vitro fertilization and embryo transfer (IVF), 257 of gamete intrafallopian transfer (GIFT) and 217 of pronuclear stage tubal transfer (PROST) were initiated. The clinical pregnancy rates per cycle started were 10.8% for IVF, 16.3% for GIFT and 15.7% for PROST. As a result of improvement in ovarian stimulation and embryo culture, the success rate of the program increased in recent years. The pregnancy rate of IVF per embryo transfer was 20.2% in 1995. Embryo cryopreservation program was started in 1992. Since then, 664 cycles of replacement of frozen-thawed embryos were completed with a pregnancy rate of 14.6% per cycle. One hundred and forty-three cycles of assisted fertilization using various techniques, namely partial zona dissection, subzonal sperm injection and intracytoplasmic sperm injection, were performed. The success rate was the highest for the latter technique with a pregnancy rate of 14% per transfer cycle. A prospective randomized control trial on the use of coculture in assisted reproduction had also been done. Results indicated that coculture of embryos with human oviductal cells improved the implantation rate of the embryos. CONCLUSION: Various technique development have been made to improve the success rate of assisted reproduction as well as the quality of treatment of infertility.

Embryo Transfer↗

Register data on Assisted Reproductive Technology (ART) in Europe including a detailed description of ART in Denmark.

The European Society for Human Reproduction and Embryology (ESHRE) has monitored Assisted Reproduction in Europe since 1997. In 2001, 579 clinics from 23 countries reported 289,690 treatment cycles with: in vitro fertilization (IVF) 120,946, intracytoplasmatisk sperm injection (ICSI) 114,378, frozen embryo replacements (FER) 47,195 and egg donation (ED) 7,171. Intrauterine inseminations are less consistently reported, but in 2001, 15 countries reported 67,124 cycles (IUI-H 52 949 and IUI-D 14 185). Data from 2001 showed that in 12 countries, where all clinics reported the in vitro techniques to the register, 829 treatment cycles were performed per million inhabitants. The availability was highest in the Nordic countries (range 975-1,923 cycles). The proportion of infants born after ART with in vitro techniques ranged from 0.2% in Latvia to 3.9% in Denmark. In general, the impact of the in vitro techniques on the birth rate is highest in the Nordic countries (range 2.2-3.9%). Denmark is the only country with an established National ART reporting system involving all ART treatments both with the in vitro techniques and intrauterine inseminations. In the year 2002, a total of 20,837 treatment cycles were performed. The result was that 6.2% of all infants were born after assisted reproduction.

Birth Rate↗