The objective of this study was to analyze the effect of the addition of alanine, glycine and glutamine on frozen seminal extender of Mangalarga marchador breed stallions. Five stallions were used from the Lugavi stables. Three ejaculates from each stallion were divided into six treatments: without the addition of amino acids, addition of 40 mM alanine, addition of 40 mM glycine, addition of 60 mM glutamine, addition of 7 mM glycine, alanine 7 mM + 20 mM glutamine and addition of 40 mM of glycine + 40 mM of alanine + 60 mM of glutamine to conventional frozen extender. The parameters evaluated were total motility, progressive motility, straightness, linearity, path velocity, progressive velocity, track speed, lateral amplitude and beat frequency by computer assisted sperm analysis (CASA), functionality of plasmatic membrane by hypo-osmotic shock and acrossomal membrane integrity by the FITC-PSA test. No improvement was found in the kinematic parameters and sperm motility and nor in membrane functionality but the addition of amino acids to seminal extender resulted in a higher integrity of the acrossomal membrane. The best results obtained in this test are with 40 mM alanine (78.6 ± 13.6), 40 mM glycine (74.7 ± 19.6) or 7 mM glycine, alanine 7 mM + 20 mM glutamine (76.8 ± 17.5), however, more studies should be conducted to reach the ideal concentration of these components.
amino acid; equine; freezing; plasmatic membrane; sperm