Received: Revised: Accepted: December 31, 2012 June 19, 2013 August 07, 2013 In the present study, effects of stress-free and stressful seasons on certain physical and biochemical attributes of semen of Cholistani AI bulls were investigated. A total of 382 ejaculates from six bulls were collected at weekly intervals during four seasons viz. stress-free autumn (October-November), stressful winte...

Fertility of frozen-thawed bull sperm is reduced by cryopreservation. Freezing-thawing procedures can result in as much as a sevenfold fertility decrease. Sperm mortality and loss of motility do not fully explain the reduced fertility of cryopreserved semen; they may be partially explained by the loss of sperm surface proteins, which are necessary for fertilization. We have previously identifie...

A combination of flow cytometric sperm sorting of X and Y chromosome-bearing sperm (X and Y sperm) and computer-assisted sperm analysis (CASA) for measuring sperm motility allows assessment of motion parameters in the two populations. Bull sperm were separated into X and Y populations by flow cytometry following staining with the DNA-binding dye Hoechst 33,342. The motion parameters differed de...

The study was conducted to determine the effect of 7-dehydrocholesterol loaded cyclodextrin (7-DHCLC) and cholesterol-loaded cyclodextrin (CLC) on changes of bull sperm motility during short term storage (+4°C). Collected ejaculates were pooled and divided into 7 groups, as following one control (C); three 7-DHCLC and the other three CLC concentrations. Diluted semen samples were transferred an...

Flow cytometry was utilized to measure the influx of calcium into fresh and frozen-thawed equine and bovine spermatozoa that had been treated with either dilauroyl-phosphatidylcholine ( PC-12) or the calcium ionophore A23187 (A23187) to initiate sperm capacitation. Sperm suspensions were stained with the fluorescent calcium indicator, Fluo-3, to measure intracellular calcium concentrations and ...

The yield of flow cytometric sorted Xand Y-chromosome-bearing sperm in a given time period is an important factor in the strategies used for fertilization and the production of sex-preselected offspring. This yield is dependent on the efficiency with which the modified flow cytometer/cell sorter analyzes the DNA of spermatozoa. The efficiency is directly related to the number of sperm with the ...

Even though a practical in vitro semen assay for determining bull fertility would be of great benefit to reproductive programs [6], it is unlikely that the evaluation of a single sperm characteristic may reflect the real sperm fertilization capacity of a semen sample. Hence, finding a set of sperm characteristics considered important for predicting conception rate would be a useful method of mo...

Bulls vary greatly in semen quality, both among bulls and among ejaculates within a bull. Therefore, semen is evaluated routinely using those characteristics that are known to affect fertility. These include general appearance of the semen, volume of the ejaculate, concentration of sperm, motility, metabolic activity, percent live/dead and morphological abnormalities. The minimum levels for a s...