The differences in the embryo production potential of four rams used in a commercial embryo transfer program were examined in both in vivo and in vitro embryo production systems. Processing frozen-thawed spermatozoa through Percoll density gradients prior to in vitro insemination eliminated differences in the estimates of sperm viability between the four rams, and yet, differences in embryo production persisted throughout the in vitro culture period. However, there was no effect of ejaculate within ram on embryo production rates. In addition, the timing of the onset of the differences between the rams at each stage of in vitro embryo development were revealed. Ram 2 differed from ram 4 in the proportion of fertilized oocytes at 17 h post-insemination (pi) and by 52 h, ram 3 differed from ram 4 in the proportion of cleaved embryos, and the observed differences between ram 1 and ram 2 in their blastocyst production were initiated prior to activation of the embryonic genome. Once differences in embryo development rates were detected among the four rams, they persisted throughout the in vitro culture period. The reduced in vitro fertilization (IVF) rates from ram 2 compared with the other rams was paralleled in vivo by the significantly lower proportion of embryos recovered from ewes mated to ram 2, and this was further exacerbated by a significantly lower embryo survival rate after transfer. However, the subtle differences observed in the timing of the contribution of each sire to embryo development during in vitro culture were not able to be detected in vivo. However, the higher proportions of transferable quality blastocysts obtained from ewes mated to ram 4 did not result in increased embryo survival throughout the remainder of gestation. Therefore, in this study, the blastocyst production potential for a particular sire, either in vitro or in vivo, does not necessarily reflect the potential for the production of live offspring.

Surveys of enteric and urinary helminth infections were carried out in 1999 among 501 schoolchildren and among 320 adolescents and young adults participating in a study of immune responses to BCG vaccine in Karonga District, northern Malawi. Hookworm, Schistosoma mansoni and S. haematobium infections were detected in 64%, 27% and 20% of schoolchildren and in 55%, 40% and 25% of the immunology study subjects, respectively. Other helminths were appreciably less common. The prevalence of 'at least one' helminth infection was 76% among schoolchildren, ranging from 60% to 92% in the 4 schools, and was 79% in the immunology study participants. There was no evidence for an association between the presence of a BCG scar and presence or intensity of infection with worms in the schoolchildren, nor evidence that BCG vaccination of adolescents and young adults had any effect on the prevalence of helminth infections 1 year later.

An in vitro culture system for producing ovine embryos is described, in which heat inactivated sheep serum was used as a protein source for maturation, fertilization and 7-d culture phases. Ovaries obtained from a commercial abattoir were used as the source of mature ewe (285) and lamb oocytes (356), which were subsequently cultured in this system to yield similar mean cleavage rates of 91 and 92%, respectively, but significantly different (P<0.025) proportions for blastocysts/cleaved oocytes (46 and 18%). At Days 7 or 8 of culture, embryos from each source were transferred, either singly (ewe-derived) or in pairs (ewe- and lamb-derived), to hormonally synchronized recipient ewes, resulting in the birth of lambs ranging in weight from 2.5 to 8.8 kg for singletons and 2.6 to 8.0 kg for twins. Mean gestation length of 153.4 ± 0.5 d (range 151 to 160) was slightly longer than the expected norm of about 150 d. The pregnancy rate was significantly higher after the transfer of embryo pairs (64%) than single (39%) embryos, while survival of lambs to weaning was greater for singleton (80%) than for twin lambs (43%). Some factor(s) in the culture media, such as growth factors in the sera, may have a mitogenic effect on embryonic cells, or it may alter the distribution of cells to the trophectoderm and inner cell mass, resulting in enhanced body growth rates.

Objective: To review the available evidence concerning the fitting, management, and efficacy of pessaries used to treat stress incontinence.To describe a method of fitting and managing incontinence pessaries.Methods: An electronic search of the English language literature discussing pessaries and stress urinary incontinence was conducted using the following databases: PubMed (1968–2000), Cochrane Database of Systematic Reviews (CHID), HSTAT, Old Medline, Research Index, and Serline.Results: Twelve journal articles, two book chapters, and a pamphlet were found that discussed the use of pessaries to treat stress incontinence.None of the articles provided detailed discussions of fitting and management of incontinence pessaries and none had any results of this treatment option for stress urinary incontinence.Conclusion: The current literature contains few details concerning pessary care and no scientific evidence for the effectiveness of pessary treatment of stress urinary incontinence.Objectif : Passer en revue les données publiées sur la mise en place, la gestion et l’efficacité des pessaires utilisés pour le traitement de l’incontinence à l’effort et décrire une méthode de mise en place et de gestion de ces dispositifs.Méthode : Une recherche des publications en langue anglaise portant sur les pessaires et l’incontinence urinaire à l’effort a été faite à partir des bases de données suivantes : PubMed (1968–2000), Cochrane Database of Systematic Reviews (CHID), HSTAT, MEDLINE (ancien), Research Index, et SERLINE.Résultats : Cette recherche a produit douze articles de revues, deux chapitres de livres et un feuillet portant sur l’utilisation des pessaires pour le traitement de l’incontinence à l’effort. Aucun des articles ne comportait une discussion détaillée de la mise en place et de la gestion des pessaires pour le traitement de l’incontinence et aucun ne présentait de résultats sur ce traitement pour l’incontinence urinaire à l’effort.Conclusion: Les publications actuelles contiennent peu de détails sur les soins au pessaire et il n’existe aucune donnée scientifique sur son efficacité pour le traitement de l’incontinence urinaire à l’effort.