Capacity of boar spermatozoa to bind zona pellucida proteins in vitro in relation to fertilization rates in vivo.

The purpose of this study was to determine variation among boars in the percentage of sperm in an ejaculate that express enhanced binding of zona pellucida proteins during treatment for capacitation in vitro, and to determine whether this relates to fertilizing ability in vivo. Ejaculates (n=35) were collected from 12 boars. A sample of each ejaculate was treated for capacitation in vitro.

Effects of exposure of epididymal boar spermatozoa to seminal plasma on the binding of zona pellucida proteins during in vitro capacitation.

The purpose of the investigation was to determine whether seminal plasma plays a role in the increase during in vitro capacitation of the number of boar spermatozoa with enhanced binding of zona pellucida proteins. Ejaculated spermatozoa and spermatozoa collected from the caudae epididymides of boars were incubated at 39 degrees C in a Tyrode's IVF medium. During incubation, the zona binding ability of individual spermatozoa was assessed with fluorescein-conjugated solubilized zona pellucida proteins (FITC-sZP), using a flow cytometer.

In vitro phagocytosis of boar spermatozoa by neutrophils from peripheral blood of sows.

A considerable number of spermatozoa are used in each sow in routine artificial insemination. However, within a few hours after insemination, many spermatozoa are phagocytosed by polymorphonuclear leucocytes. Some aspects of sperm transport in the female genital tract in the sow have been thoroughly investigated, whereas little is known about the mechanisms involved in the phagocytosis of spermatozoa, or about which spermatozoa (fresh, capacitated or dead) are the most susceptible to ingestion by polymorphonuclear leucocytes.

Enhanced binding of zona pellucida proteins to the acrosomal region of the intact boar spermatozoa in response to fertilizing conditions: a flow cytometric study.

In this investigation we sought to determine whether sperm capacitation in vitro is accompanied by changes in the functional presence of zona binding sites on the plasma membrane of boar spermatozoa. During sperm incubation at 39 degrees C in various modifications of a Tyrode's-based in vitro fertilization medium, the zona binding ability of individual spermatozoa was assessed with fluorescein-conjugated solubilized zona pellucida proteins, using a flow cytometer. Propidium iodide was routinely included to allow simultaneous assessment of membrane integrity; rhodamine-conjugated peanut agglutinin was used to assess acrosomal status.