Characteristics of captive Japanese black bears (Ursus thibetanus japonicus) semen collected by electroejaculation with different voltages for stimulation and frozen-thawed under different conditions

Okano, Tsukasa; Murase, Tetsuma; Yayota, Chizuru; Komatsu, Takeshi; Miyazawa, Keiji; Asano, Makoto; Tsubota, Toshio

doi:10.1016/j.anireprosci.2005.10.002

Cited by 26 publications

(20 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Semen cryopreservation is one of the most important techniques for species conservation as a genetic resource. There are reports of semen cryopreservation in ursids, including giant pandas (Ailuropoda melanoleuca) [13,14,18], Hokkaido brown bears (Ursus arctos yesoensis) [7], and Japanese black bears [11,12]. However, although efforts to establish an optimal technique are important, no comparative studies of different glycerol concentrations of diluents for bear semen cryopreservation have been reported.…”

mentioning

confidence: 99%

“…We have customarily used an egg yolk-citrate-based diluent with 8% glycerol in our laboratory for freezing Japanese black bear semen [11,12]. However, we have found percent viability and intact acrosomes of frozen-thawed spermatozoa to be better when freezing semen at lower glycerol concentrations of 4 and 6%.…”

mentioning

confidence: 99%

“…Semen was collected once from each animal by electroejaculation during the mating season in June and July 2005. Electroejaculation was conducted according to the method of Kojima et al [9] and our previous study [12] with some modifications.Briefly, the animals were immobilized by intramuscular administration of zolazepam HCl and tiletamine HCl (Zoletil, Virbac, Carrors, France; 9 mg/kg of the estimated body weight). After immobilization, the penis was cleaned, and the bladder was then emptied and flushed with sterile physiological saline by catheterization (5-fr.…”

mentioning

confidence: 99%

mentioning

confidence: 99%

“…Semen cryopreservation was performed according to the method of our previous study [11,12] with some modifications. Briefly, the diluent used was egg yolk-TRIS-citrateglucose extender [15] supplemented with 0.52 mg/ml of potassium penicillin G and 0.8 mg/ml of streptomycin sulphate (first extender).…”

mentioning

confidence: 99%

See 4 more Smart Citations

Characteristics of Frozen-Thawed Spermatozoa Cryopreserved with Different Concentrations of Glycerol in Captive Japanese Black Bears (Ursus thibetanus japonicus)

Okano

Nakamura

Komatsu³

et al. 2006

The Journal of Veterinary Medical Science

View full text Add to dashboard Cite

ABSTRACT. Seven mature Japanese black bears were used as semen donors, and a total of 7 semen samples collected from the animals by the electroejaculation method were cryopreserved in liquid nitrogen. Egg yolk-TRIS-citrate-glucose extender was used, and the effects of different final concentrations of glycerol, at 4-12% (v/v), on frozen-thawed spermatozoa were examined. No significant difference was observed in percent motility or percent abnormal morphology of frozen-thawed spermatozoa among the different glycerol concentrations. Percent viability and percent intact acrosomes of spermatozoa cryopreserved with 4 and 6% glycerol were significantly higher than those with 10 and 12% glycerol. These results suggest that a suitable glycerol concentration for freezing Japanese black bear semen within the range tested would be 4-6%. KEY WORDS: glycerol, Japanese black bear, semen cryopreservation.J. Vet. Med. Sci. 68(10): 1101-1104, 2006 The Japanese black bear (Ursus thibetanus japonicus) is an endangered species in some areas of Japan [5]. Semen cryopreservation is one of the most important techniques for species conservation as a genetic resource. There are reports of semen cryopreservation in ursids, including giant pandas (Ailuropoda melanoleuca) [13,14,18], Hokkaido brown bears (Ursus arctos yesoensis) [7], and Japanese black bears [11,12]. However, although efforts to establish an optimal technique are important, no comparative studies of different glycerol concentrations of diluents for bear semen cryopreservation have been reported. Glycerol has been widely used as a cryoprotectant in semen cryopreservation in domestic and non-domestic animals [19], although optimal glycerol concentrations vary among species [1]. Glycerol, a cryoprotective agent, exerts toxic effects on spermatozoa, such as plasma membrane rupture and acrosomal damage [6,10].The objective of the present study was to examine the effect of different glycerol concentrations of diluents for semen cryopreservation in Japanese black bears.Seven mature male Japanese black bears over 4 years of age at Ani Mataginosato Bear Park, Akita, Japan (N 40°, E 140.4°), were used as semen donors. They had been kept with 6 females and approximately 30 other males and had been allowed to mate freely with the females. Semen was collected once from each animal by electroejaculation during the mating season in June and July 2005. Electroejaculation was conducted according to the method of Kojima et al. [9] and our previous study [12] with some modifications.Briefly, the animals were immobilized by intramuscular administration of zolazepam HCl and tiletamine HCl (Zoletil, Virbac, Carrors, France; 9 mg/kg of the estimated body weight). After immobilization, the penis was cleaned, and the bladder was then emptied and flushed with sterile physiological saline by catheterization (5-fr. polypropylene urinary catheter; Sovereign, Sherwood Medical, MO, U.S.A.). A collection catheter (8-fr. Sovereign) whose tip had been cut off to widen the hole was inserted into the urethra...

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Characteristics of Frozen-Thawed Spermatozoa Cryopreserved with Different Concentrations of Glycerol in Captive Japanese Black Bears (Ursus thibetanus japonicus)

Okano

Nakamura

Komatsu³

et al. 2006

The Journal of Veterinary Medical Science

View full text Add to dashboard Cite

show abstract

Reproductive tactics and mating contexts affect sperm traits in horseshoe crabs (Limulus polyphemus)

Sasson

Johnson

Brockmann

2015

Behav Ecol Sociobiol

View full text Add to dashboard Cite

Spermatozoa recovery and post-thawing quality of brown bear ejaculates is affected for centrifugation regimes

et al. 2011

View full text Add to dashboard Cite

Sperm cryopreservation protocols for brown bear (Ursus arctos) require the centrifugation of semen samples to increase sperm concentration and to clean urine in contaminated samples. We evaluated the effect of centrifugation regimes (time and relative centrifugal force-RCF) on the quantity of sperm recovered and the quality of postthawed sperm. Thirteen brown bears were electroejaculated. The ejaculates were diluted 1:1 in Tris-citric acid-glucose (TCG) extender and centrifuged with different RCF/time combinations: 600×g, 1,200×g and 2,400×g, for 3, 6 or 12 min. After centrifugation, spermatozoa were diluted in TES-Tris-fructose extender with egg yolk and glycerol (final glycerol concentration of 8%) and frozen in 0.25-mL straws. In the post-thawed semen, motility was assessed by CASA, and acrosomal status (PNA-FITC), viability (SYBR-14 with propidium iodide) and chromatin status (SCSA) were determined by flow cytometry. The longest centrifugation time (12 min) significantly decreased some motility parameters. Sperm recovery significantly decreased in brown bear at 600×g. Our results suggest that brown bear spermatozoa are more sensitive to long centrifugation times than to high RCF. Centrifugation regimes showed no effects on the post-thawing chromatin status. We recommend preparing the brown bear semen for freezing by centrifugation 1,200×g or 2,400×g for 6 min, after electroejaculation and dilution 1:1 in TCG extender, since these procedures increase the spermatozoa recovery without harmful effects on the post-thawed quality of brown bear spermatozoa.

show abstract

Characteristics of captive Japanese black bears (Ursus thibetanus japonicus) semen collected by electroejaculation with different voltages for stimulation and frozen-thawed under different conditions

Cited by 26 publications

References 28 publications

Characteristics of Frozen-Thawed Spermatozoa Cryopreserved with Different Concentrations of Glycerol in Captive Japanese Black Bears (Ursus thibetanus japonicus)

Characteristics of Frozen-Thawed Spermatozoa Cryopreserved with Different Concentrations of Glycerol in Captive Japanese Black Bears (Ursus thibetanus japonicus)

Reproductive tactics and mating contexts affect sperm traits in horseshoe crabs (Limulus polyphemus)

Spermatozoa recovery and post-thawing quality of brown bear ejaculates is affected for centrifugation regimes

Contact Info

Product

Resources

About