Effects of Semen Extenders and Storage Temperatures on Characteristics of Frozen-Thawed Bryde's (Balaenoptera edeni) Whale Spermatozoa

Abstract

Abstract. The present study investigated effects of three semen extenders and storage temperatures on post-thaw characteristics of Bryde's whale spermatozoa. Spermatozoa were collected from the vasa deferens of three mature Bryde's whales captured during the Japanese whale research in the north-west Pacific (May to August 2007) after death. The three semen extenders used for freezing were 1) a commercialized synthetic extender (AndroMed: AM), 2) Trisbased + 10% bovine serum albumin (BSA) and 3) Tris-based + egg yolk (EY). The sperm samples from the three whales were frozen with the three extenders, and the post-thaw spermatozoa were stored at three different temperatures (35 C; 20-25 C, room temperature; and 5 C) for 0, 6, 12, 24, 48 and 96 h. At each time-point, total and progressive motility (PM), viability (live or dead), the hypo-osmotic test, defective acrosomes and malformation were examined. Immediately after thawing, AM resulted in similar recovery rates (60.4 and 83.3%) in 2 of the 3 whales examined and had comparable post-thaw recovery rates to those obtained using the EY and BSA extenders. Immediately after thawing, the proportion of PM in EY (17.6%) was higher (P<0.05) than that in BSA (15.0%). In the hypo-osmotic test, the proportions of AM (26.0%) and BSA (25.2%) were higher (P<0.05) than that of EY (17.3 %). The three extenders had similar viabilities (36.7, 37.9 and 32.1%, respectively), but the viability of BSA was higher (P<0.05) than that of EY. The present study showed that a synthetic semen extender, AndroMed, could be used for cryopreservation of whale spermatozoa in addition to Tris-based extenders containing bovine serum albumin or egg yolk. Storage of the post-thaw Bryde's whale spermatozoa was better at 5 C than at room temperature or 35 C. The frozen-thawed Bryde's whale spermatozoa maintained their motility and viability for at least two days at room temperature and for four days at 5 C. [5] used Bryde's (Balaenoptera edeni) whale spermatozoa freshly-diluted with m-PBS and stored at 4 C for in vitro fertillization (IVF) in the field. However, it has not been demonstrated yet how long the viability of frozen-thawed spermatozoa is maintained and what the most appropriate temperature is for post-thaw storage in baleen whales, including Bryde's whales. For domestic animals including sheep, post-thaw semen is usually maintained at 37 C for examinations of their motility and viability, but the body temperatures (35.5 to 37 C) of dolphins and whales are lower than those of other mammals, and no one has measured the body temperatures of live baleen whales, including Antarctic minke and Bryde's whales.There has been recent movement to eliminate all animal ingredients, such as egg yolk, milk and even bovine serum albumin (BSA), from semen extenders. Our recent studies [6-8] on artificial insemination (AI) in sheep have clearly shown that a soybean-based semen extender (AndroMed) is useful and comparable to the conventional semen extenders containing egg yolk or BSA. Fukui et al. [6] compared ...

The effect of bovine serum albumin and fetal calf serum on sperm quality, DNA fragmentation and lipid peroxidation of the liquid stored rabbit semen

“…Furthermore, the percentages of intact plasma membrane and motility were better than controls at 72 h in the presence of BSA and FCS in this study. These results are in agreement with the previous results in ram [31], whale [23], turkey [8], and buffalo [18] semen. These studies showed that BSA significantly improved semen characteristics.…”

Effects of Bovine Serum Albumin on Boar Sperm Quality During Liquid Storage at 17°C

“…The results also demonstrated that the effective conservation time was more than 6.5 days, and sperm motility achieved 75% after 3 days conservation. These results were in agreement with previous studies about ram (Matsuoka et al 2006), whale (Hiwasa et al 2009), buffalo (El-Kon 2011) and rabbit (Sarıozkan et al 2013). These studies suggested that BSA could improve sperm motility significantly after preservation.…”

“…Some studies found that serum albumin could largely prevent these effects (Suter et al 1979). Bovine serum albumin (BSA) is a kind of serum albumin which could protect sperm efficiently (Matsuoka et al 2006;Hiwasa et al 2009;El-Kon 2011;Osman et al 2012;Sarıozkan et al 2013).…”