The effect of astaxanthin supplementation on the post‐thaw quality of dog semen

Abstract

Astaxanthin is a member of the carotenoid family well known for its anti‐cancer, anti‐diabetic, anti‐inflammatory and antioxidant nature. This study was designed to investigate the effects of astaxanthin supplementation of the extender (buffer 2) on post‐thaw dog semen quality. Semen from four healthy dogs was collected by digital manipulation twice a week. The ejaculates were pooled, washed, divided into four equal aliquots, diluted with the extender supplemented with different concentrations of astaxanthin (0, 0.5, 1 and 2 µM) and cryopreserved. The results showed that 1 µM astaxanthin was the optimum concentration that led to significantly higher (p < .05) post‐thaw motility, kinematic parameters and viability than the other groups. In comparison with the control group, sperm samples supplemented with 1 µM astaxanthin showed significantly higher (p < .05) sperm counts with intact membranes (55.7 ± 0.6% vs. 51.3 ± 0.9%), intact acrosome (58.4 ± 0.7% vs. 53.5 ± 0.6%), active mitochondria (54.9 ± 0.5% vs. 42.6 ± 0.6%) and normal chromatin (67.6 ± 0.9% vs. 61.7 ± 0.6%). Furthermore, astaxanthin‐supplemented samples showed significantly lower expression levels (p < .05) of pro‐apoptotic (BAX), oxidative induced DNA damage repair (OGG1), oxidative stress‐related (ROMO1) genes and higher expression levels of anti‐apoptotic (BCL2), and sperm acrosome‐associated (SPACA3) genes compared to the control. Thus, supplementation of 1 µM astaxanthin in semen extender results in improved freeze‐thaw sperm quality of the dog.

Resveratrol supplementation into extender protects against cryodamage in dog post-thaw sperm

“…All chemical used in the experiment were purchased from Sigma-Aldrich (St. Louis, MO, USA) unless otherwise stated. Sperm cryopreservation and post-thaw quality assessment were performed following according procedures reported in our previous study [ 41 ].…”

“…The sperm washing and dilution system was prepared as previously described [ 41 ]. Buffer 1 used for sperm washing was composed of Tris (hydroxymethyl) aminomethane, 198.11 mM; citric acid, 72.87 mM; fructose, 44.39 mM; and kanamycin sulfate, 0.25 mM dissolved in distilled water.…”

“…Many investigators have focused on the use of antioxidants in the freezing media to reduce the negative effects of ROS on sperm [ 2 , 4 , 10 ]. Our previous findings showed that supplementation of dog cryopreservation medium with kinetin [ 42 ] and astaxanthin [ 41 ] improved the post-thaw motility, viability, and structural integrity of dog sperm, and we aimed to assess the effect of resveratrol (RSV) as an alternative antioxidant.…”

Semen evaluation: methodological advancements in sperm quality-specific fertility assessment

“…Fluorescent probes such as Hoechst or propidium-iodide (PI) are either used alone or in combination with other permeable fluorochromes such as carboxyfluorescein diacetate or SYBR [ 114 – 116 ]. Complementary techniques, including flow cytometry and fluorimetry, can be helpful in improving measurement precision, as large numbers of fluorochrome-stained sperm can be assessed in a short duration of time [ 117 , 118 ]. The recent development of the CASA technique has allowed the automated measurement of sperm plasma membrane integrity [ 119 ].…”

Effects of Resveratrol Supplementation on the Motility, Structural Integrity, and Mitochondrial Function of Freeze-Thawed Dog Sperm

“…Sperm cryopreservation and post-thaw quality assessment were performed following previously reported protocols [17] and as detailed here. Pooled sperm samples were adjusted to a concentration of 200  10 6 cells/mL with buffer 1.…”