Quality assessment of bovine cryopreserved sperm after sexing by flow cytometry and their use in in vitro embryo production

The objective was to evaluate the structural and functional quality of bull sperm after sexing by flow cytometry Frozen non-sexed (NS) sexed for X (SX) and sexed for Y (SY) sperm from four bulls was used Frozen-thawed sperm was analyzed for motility, sperm head agglutination morphology capacitation and integrity of the plasma membrane acrosome and chromatin After Percoll centrifugation (45 60% gradients) the pellet was used for sperm analysis or IVF Data were analyzed using generalized linear models (P < 0 05) and were reported as least squares means +/- standard error (SEM) Based on sperm evaluations NS sperm had better (P < 0 05) quality than sexed sperm including higher motility and greater percentages of cells with an intact membrane and acrosome (58 0 +/- 3 0, 58 2 +/- 30 and 60 9 3 3) than SX (29 6 +/- 1 3 360 +/- 2 9, and 371 +/- 3 3), and SY (26 2 +/- 2 1, 364 +/- 2 9 and 37 5 +/- 3 3) There were no differences (P > 0 05) among groups for fertilization and cleavage rates Similarly, blastocyst rate on Day 8 (Day 0 = day of insemination) did not differ among groups (22 2 +/- 3 2 18 1 +/- 3 3, and 14 8 +/- 2 9 for NS SX and SY, respectively) Regarding embryo development kinetics all groups had similar developmental stages from Days 6 to 9 Although the sex sorting procedure affected sperm characteristics it did not significantly affect fertilization or embryo development (C) 2010 Elsevier Inc All rights reserved