Attempt at Intracytoplasmic Sperm Injection of In Vitro Matured Oocytes in Common Minke Whales (Balaenoptera acutorostrata) Captured During the Kushiro Coast Survey

Abstract

Abstract. The present study was conducted during the Kushiro Coast Survey in an attempt to produce common minke whale embryos. In Experiment 1, we attempted to determine the appropriate culture duration (30 or 40 h) for in vitro maturation (IVM) of immature oocytes using the Well of the Well method. In Experiment 2, and intracytoplasmic sperm injection (ICSI) was applied to matured oocytes from prepubertal and adult common minke whales after IVM culture (40 or 48 h), and then their embryonic development was assessed. In Experiment 1, the maturation rate of oocytes cultured for 40 h (30.4%) was significantly higher than that of oocytes cultured for 30 h (6.8%; P<0.01). In Experiment 2, a total of 35 and 46 immature oocytes derived from adult (n=2) and prepubertal (n=6) minke whales, respectively, were cultured for 40 or 48 h. The maturation rate in the oocytes from the adult whales (34.2%) tended to be higher than that of the oocytes from the prepubertal whales (19.6%), but there was no significant difference. Following ICSI, 3 out of the 10 inseminated and cultured oocytes from the adult whales cleaved (2-, 8-, and 16-cell stages); all of these oocytes had been matured for 40 in culture. However, these oocytes did not develop to further stages. Only one of the 6 oocytes derived from the prebuertal whales, IVM cultured for 40 h and inseminated, developed to the 4-cell stage. The present results indicate that a 40 h IVM culture produces significantly higher rates of in vitro maturation than a 30 h IVM culture for common minke whale oocytes. Following ICSI, some oocytes cleaved to the 16-cell stage, but no further development was observed.

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

“…At present, it would be impractical to collect ejaculated semen from live baleen whales, including Bryde's whales. However, once cryopreservation of sperm from dead baleen whales and storage of post-thaw spermatozoa are possible, as shown in the present study, several assisted reproductive technologies can be applied to produce whale embryos through IVF or intracytoplasmic sperm injection (ICSI) [5,19]. Indeed, AI with fresh-diluted, frozen-thawed or sex-sorted spermatozoa has been successful in killer whales [20] and bottlenosed dolphins [21].…”

“…3). Anti-oxidants, such as amino acids like taurine, hypotaurine [16,17] and hyaluronic acid [19], may be needed for maintenance of motility and viability at 5 C or room temperature.…”

Attempts atin vitrofertilization and culture ofin vitromatured oocytes in sei (Balaenoptera borealis) and Bryde's (B. edeni) whales

“…Accordingly, several studies on ARTs with respect to IVM (Fukui et al . 1997a, 2007; Asada et al ., 2000, 2001a; Iwayama et al ., 2005; Fujihira et al ., 2006), cryopreservation of oocytes (Asada et al ., 2000; Iwayama et al ., 2004; Fujihira et al ., 2006), IVF (Fukui et al ., 1997b; Asada et al ., 2001a), intracytoplasmic sperm injection (ICSI) (Asada et al ., 2001b; Fujihira et al ., 2006; Fukui et al ., 2007) and inter-species somatic cell nuclear transfer (Ikumi et al ., 2004) have been conducted in common minke ( Balaenoptera acutorostrata ) and Antarctic minke ( B. bonaerensis ) whales. However, still there is no information on IVM, IVF and embryo development of oocytes derived from other whales.…”

Production of Sei Whale (Balaenoptera borealis) Cloned Embryos by Inter- and Intra-Species Somatic Cell Nuclear Transfer

“…56: [131][132][133][134][135][136][137][138][139] 2010) esearch on in vitro maturation (IVM), in vitro fertilization (IVF), somatic cell nuclear transfer (SCNT) and in vitro culture (IVC) of whale embryos will greatly contribute to our basic understanding of whale reproductive physiology, resulting, ideally, in the application of various assisted reproductive technologies (ARTs) to increase the population and aid in management of cetaceans. Several studies on ARTs with respect to IVM [1][2][3][4][5][6], cryopreservation of oocytes [2,5,7], IVF [3,8], intracytoplasmic sperm injection (ICSI) [5,6,9] and interspecies SCNT [10] have been conducted in Common minke (Balaenoptera acutorostrata) and Antarctic minke (B. bonaerensis) whales. Recently, we attempted for the first time to produce embryos of sei (B. borealis) whales by IVF of IVM oocytes in a research based ship [11].…”