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Author

M. Kaproth

Bio: M. Kaproth is an academic researcher from Ithaca College. The author has contributed to research in topics: Sperm & Semen. The author has an hindex of 10, co-authored 17 publications receiving 551 citations.
Topics: Sperm, Semen, Semen quality, Spermatogenesis, Extender

Papers
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Journal ArticleDOI
TL;DR: Results demonstrate differential extender effects on postthaw semen quality and indicate that altering extender composition or sequence of adding extender components may improve postthawed quality of cryopreserved sperm.

102 citations

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TL;DR: These additives, useful as cryopreservatives or membrane protectors in other systems, did not enhance the fertility of sperm frozen in whole milk.

86 citations

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TL;DR: This approach to counting sperm provides an excellent procedure for quality control of sperm numbers in processed semen and the accuracy of counting sperm in straws based on preextension spectrophotometric determination of sperm concentration is demonstrated.

85 citations

Journal ArticleDOI
TL;DR: The results indicate that, under good conditions, total sperm numbers per straw can be reduced to 10 x 10(6) total sperm with a reduction of nonreturn rates at 59 d, for most bulls, of about 1 percentage unit from the maximum when professional inseminators are use.

84 citations

Journal ArticleDOI
TL;DR: Random samples of cryopreserved, milk-extended semen were evaluated at thawing and during 3-h incubation to suggest semen quality of young bulls was related to subsequent quality as mature bulls.

75 citations


Cited by
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Journal ArticleDOI
TL;DR: Evidence for new approaches for improving the performance of cryopreserved semen is offered and factors affecting the proportion of survivors and functional status of survivors are reviewed.

1,383 citations

Journal ArticleDOI
TL;DR: Knowledge of the biology of sperm transport can inspire improvements in artificial insemination, IVF, the diagnosis of infertility and the development of contraceptives.
Abstract: At coitus, human sperm are deposited into the anterior vagina, where, to avoid vaginal acid and immune responses, they quickly contact cervical mucus and enter the cervix. Cervical mucus filters out sperm with poor morphology and motility and as such only a minority of ejaculated sperm actually enter the cervix. In the uterus, muscular contractions may enhance passage of sperm through the uterine cavity. A few thousand sperm swim through the uterotubal junctions to reach the Fallopian tubes (uterine tubes, oviducts) where sperm are stored in a reservoir, or at least maintained in a fertile state, by interacting with endosalpingeal (oviductal) epithelium. As the time of ovulation approaches, sperm become capacitated and hyperactivated, which enables them to proceed towards the tubal ampulla. Sperm may be guided to the oocyte by a combination of thermotaxis and chemotaxis. Motility hyperactivation assists sperm in penetrating mucus in the tubes and the cumulus oophorus and zona pellucida of the oocyte, so that they may finally fuse with the oocyte plasma membrane. Knowledge of the biology of sperm transport can inspire improvements in artificial insemination, IVF, the diagnosis of infertility and the development of contraceptives.

941 citations

Journal ArticleDOI
TL;DR: The data presented provide strong evidence that oxygen free radicals are produced during freezing and thawing of bovine spermatozoa and suggest that these reactive oxygen species may be a cause for the decrease in sperm function following cryopreservation.
Abstract: In the present study, we provide evidence for the production of reactive oxygen species (ROS) during cryopreservation of bovine spermatozoa. Cooling and thawing of spermatozoa cause an increase in the generation of superoxide radicals. Although nitric oxide production remains unaltered during sperm cooling from 22-4 degrees C, a sudden burst of nitric oxide radicals is observed during thawing. Increase in lipid peroxidation levels have been observed in frozen/thawed spermatozoa and appears to be associated with a reduction in sperm membrane fluidity as detected by spin labeling studies. The data presented provide strong evidence that oxygen free radicals are produced during freezing and thawing of bovine spermatozoa and suggest that these reactive oxygen species may be a cause for the decrease in sperm function following cryopreservation. Mol. Reprod. Dev. 59: 451-458, 2001.

500 citations

Journal ArticleDOI
TL;DR: The historical and current methods used for storage of bovine semen are described and the essential physiological differences between liquid and frozen semen are addressed.

388 citations

Journal ArticleDOI
TL;DR: There has been no recent effort to develop a prediction of fertility or fecundity based on sperm characteristics, and achievement of this goal may be elusive.
Abstract: This paper highlights the most critical aspects of the problem of predicting fertility. To determine if a laboratory test(s) is highly correlated with fertility it is essential to have: a) specific, precise and accurate laboratory tests, and b) precise and accurate fertility data. Acquisition of precise and accurate data for laboratory tests and fertility of spermatozoa in the same sample is not easy. Data derived from in vitro fertilization are not tests of fertility, because only a subset of the attributes important for fertilization in vivo are tested. Because of deficiencies in fertility data, there probably is no valid report for human spermatozoa correlating results of laboratory tests and fertility, and very few valid studies for laboratory or domesticated animals. There is little doubt that objective measures of sperm motion, acrosomal status, or other characteristics are significantly correlated with fertility. However, establishment of the correlations between a group of attributes and fertility is not the question of interest. The goal is prediction of fertility. There has been no recent effort to develop a prediction of fertility or fecundity based on sperm characteristics, and achievement of this goal may be elusive.

331 citations