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CASA as an aid to selecting sperm suspensions for artificial insemination in Callithrix jacchus
Influence of semen collection method on ejaculate characteristics in the common marmoset, Callithrix jacchus
A source of normal spermatozoa (sperm) is required for many andrological and reproductive studies. Ideally the method used for semen collection should be repeatable and reliable but should not influence sperm characteristics or sperm function. Two methods of semen collection from marmosets, vaginal washing after copulation and electroejaculation, were compared in terms of the success rate in obtaining samples and the characteristics of the sperm suspensions. Vaginal washing was shown to be a reliable, repeatable, and apparently non-stressful method of obtaining ejaculates, with 8 out of 10 males ejaculating on at least four of the five attempts. The semen was of good quality as assessed by conventional means, and the sperm were highly fertile when used for artificial insemination (Al; 100% conception rate). In contrast, fewer ejaculates were obtained from the same males by electroejaculation (success rate 30%), sperm survival in vitro was reduced compared to sperm collected by vaginal washing (0.93 +/- 0.15 days for electroejaculated sperm compared to 1.98 +/- 0.3 days for sperm from vaginal washing), and the number of animals giving birth after Al was smaller (0 vs. 6; P < 0.05). The proportions of motile (74.8 vs. 70.7%), live (84.7 vs. 81%), and morphologically normal (91.9 vs. 87.6%) sperm in the ejaculates were not affected by the semen collection method, but velocity parameters, such as curvilinear velocity, straight line velocity, and average path velocity, as assessed by computerized motility analysis, were significantly lower in vaginal washings than in electroejaculates (P < 0.023, 0.008, and 0.008, respectively). Mean angular deviation and beat cross frequency were greater in vaginal washings than in electroejaculates (P < 0.016 and 0.008, respectively). Therefore the effect of semen collection method on sperm function should always be considered when designing reproductive studies
Collection of semen from marmoset monkeys (Callithrix jacchus) for experimental use by vaginal washing
Assisted reproductive techniques make an important contribution to the conservation of endangered primate species. In our laboratories marmoset monkeys ( Callithrix jacchus) are used as a model species for developing assisted reproductive technologies for New World primates. The studies require a reliable method for collecting functional sperm from these small animals. For this purpose a minimally invasive procedure, vaginal washing after natural mating, was evaluated for its suitability as a routine method of obtaining ejaculated sperm of high quality. The objective of the first series of tests was to identify a behavioural pattern which was easily discernible by the observer and provided a reliable indication that ejaculation had occurred. In a second series of tests the influence of length of separation of the male prior to copulation on the quality of the ejaculate was evaluated. Six adult ovariectomized and five adult intact females were used for vaginal washing, while their mates served as donors of ejaculates. Matings at specific times were achieved by separating the males from their females for a certain time period and subsequently introducing either their own mates or unfamiliar males to the females. After each observed mating vaginal washing was performed on the unsedated females. The seminal samples obtained were analysed for sperm concentration, the proportion of motile sperm and the proportion of live sperm. The results have shown (a) that ejaculation was indicated with a reliability of 86.1 % by the behaviour of the female, who terminates a copulation by moving away from her partner; (b) that separation of the male for up to six days had no negative effect on the sperm quality; (c) that the sperm samples were of high quality. Vaginal washing after natural matings appears to be a practical, reliable and gentle method for routinely collecting ejaculates from marmoset monkeys and possibly other New World primates
Influence of semen collection method on ejaculate characteristics in the common marmoset, Callithrix jacchus
A source of normal spermatozoa (sperm) is required for many andrological and reproductive studies. Ideally the method used for semen collection should be repeatable and reliable but should not influence sperm characteristics or sperm function. Two methods of semen collection from marmosets, vaginal washing after copulation and electroejaculation, were compared in terms of the success rate in obtaining samples and the characteristics of the sperm suspensions. Vaginal washing was shown to be a reliable, repeatable, and apparently non-stressful method of obtaining ejaculates, with 8 out of 10 males ejaculating on at least four of the five attempts. The semen was of good quality as assessed by conventional means, and the sperm were highly fertile when used for artificial insemination (Al; 100% conception rate). In contrast, fewer ejaculates were obtained from the same males by electroejaculation (success rate 30%), sperm survival in vitro was reduced compared to sperm collected by vaginal washing (0.93 +/- 0.15 days for electroejaculated sperm compared to 1.98 +/- 0.3 days for sperm from vaginal washing), and the number of animals giving birth after Al was smaller (0 vs. 6; P < 0.05). The proportions of motile (74.8 vs. 70.7%), live (84.7 vs. 81%), and morphologically normal (91.9 vs. 87.6%) sperm in the ejaculates were not affected by the semen collection method, but velocity parameters, such as curvilinear velocity, straight line velocity, and average path velocity, as assessed by computerized motility analysis, were significantly lower in vaginal washings than in electroejaculates (P < 0.023, 0.008, and 0.008, respectively). Mean angular deviation and beat cross frequency were greater in vaginal washings than in electroejaculates (P < 0.016 and 0.008, respectively). Therefore the effect of semen collection method on sperm function should always be considered when designing reproductive studies
Retrospective observation of the effect of accidental exposure to organophosphates on the success of embryo transfer in mice
Retrospective observation of the effect of accidental exposure to organophosphates on the success of embryo transfer in mice
Birth of offspring following artificial insemination in the common marmoset,Callithrix jacchus
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Fertilization-promoting peptide in reproductive tissues and semen of the male marmoset (Callithrix jacchus)
Fertilization-promoting peptide (FPP) is present in the prostate gland and semen of some mammals, and has been shown to enhance the fertilizing ability of both epididymal mouse and ejaculated human spermatozoa. The novel peptide may prove of importance for the treatment of some cases of male infertility, and a suitable animal model would be useful to test this hypothesis. To this end, we examined reproductive tissues and semen of the male marmoset for the presence of FPP. Peptides were extracted from seminal plasma, testes, prostate, and bulbourethral glands of intact and castrated male marmosets. The peptides were identified by ion-exchange chromatography followed by radioimmunoassay. The mean concentration of FPP immunoreactivity in semen from intact males was 58.7 nM (SE +/- 9.9 nM, n = 10), and anion-exchange chromatography revealed FPP as the only immunoreactive peptide present. Analysis of tissues revealed that FPP in semen was likely to be derived from the prostate gland, which contained this peptide as the major source of immunoreactivity (10.86 pmol/gland; SE +/- 4.39 pmol/gland, n = 4). Only low concentrations of FPP were detectable in the bulbourethral glands, and the peptide was undetectable in the testis. Surprisingly, FPP was readily detectable in the seminal plasma from one castrated marmoset and was present in the prostate gland from 3 castrates at levels which did not differ significantly from those in intact animals (5.47 pmol/gland, SE +/- 1.64 pmol/gland, n = 3). Plasma testosterone measurements indicated that residual circulatory androgens remained after castration, which may be consistent both with the maintenance of mating behavior and the presence of prostatic FPP. We conclude that FPP is present within the prostate gland and seminal plasma of the marmoset at concentrations consistent with a role in male fertility in this species
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