The effect of Equex STM paste and sperm morphology on post-thaw survival of cat epididymal spermatozoa

ABSTRACT. It has been shown that addition of the surfactant Orvus ES paste (OEP) and its main component sodium lauryl sulfate (SLS) to boar or dog semen before freezing improves post-thaw sperm motility and protects acrosome caps. In this study, we investigated the usefulness of the addition of OEP (0, 1, 2 and 4%) or SLS (0, 1, 2, 3 and 4 mg/ml) to cat ejaculates before freezing and their concentrations. Among the OEP addition groups, the 1% OEP group showed higher sperm motility than the other groups. Among the SLS addition groups, the 3 mg/ml SLS group showed slightly higher sperm motility and viability than the other groups. Comparison between the 1% OEP and 3 mg/ml SLS addition groups suggested a higher percentage of sperm with an acrosome cap in the 1% OEP group. The other sperm properties did not significantly differ between the 2 groups. These results indicate that addition of 1% OEP or 3 mg/ ml SLS is effective for freezing of cat ejaculated semen.KEY WORDS: acrosome cap, cat, frozen semen, orvus es paste, sodium lauryl sulfate.J. Vet. Med. Sci. 72(1): 23-27, 2010 In regard to artificial insemination (AI) with frozen feline semen, intravaginal [6,11,19] and intrauterine [6,18,19] inseminations with ejaculates have each been reported in three studies, and intravaginal [20] and intrauterine [15,20] inseminations with epididymal sperm have each been reported in one and two studies, respectively. In our 2003 year study using epididymal sperm [15], we added 7% (v/v) glycerol and 1% Orvus ES paste (OEP, also known as Equex STM paste, Nova Chemical Sales, Inc., Scituate, MA, U.S.A.) to semen as cryoprotective agents and achieved a conception rate of 27.3%. However, we did not evaluate the usefulness of addition of OEP for cryopreservation of feline semen or its optimal concentration. Addition of OEP along with glycerol for the cryopreservation of boar [12] and dog [16,17] semen has been shown to protect the acrosome caps of sperm, thereby increasing and maintaining post-thaw sperm motility for a long period of time. In 2004, Axnér et al. [5] investigated the usefulness of Equex STM paste for cryopreservation of feline epididymal sperm and showed that addition 0.5% (v/v) Equex STM paste led to greater protection of the acrosome caps of sperm after freeze-thawing than no addition, but sperm motility was lower (sperm survival was shorter) 4-6 hr after thawing than in the case of no addition. Our search of the literature revealed no studies in which addition of OEP for semen cryopreservation adversely affected post-thaw sperm motility. It remains unclear whether the results of the study by Axnér et al. [5] regarding cryopreservation of epididymal sperm apply to cryopreservation of cat ejaculates.OEP is known to contain mainly sodium lauryl sulfate (SLS), but data on its concentration and the remaining constituents have not been published. It has been suggested that the effect of SLS might be exerted by modifying the structure of egg yolk lipoproteins in the extracellular medium [4]. Kato et al. [9] employed ...

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confidence: 95%

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confidence: 95%

Usefulness of Addition of Orvus ES Paste and Sodium Lauryl Sulfate to Frozen Feline Semen

Mizutani

Sumigama²,

Nagakubo

et al. 2010

“…The frequency of immature sperm reported in feline caudal epididymal sperm varies markedly among researchers [1,10,12,15]. Furthermore, Axnér et al [2] reported that the ratio of immature sperm decreases from the caput to the cauda.…”

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confidence: 99%

“…72(6): 777-780, 2010 The total number of animals worldwide has decreased in many wildcat species, and various assisted reproductive technologies (ART) are necessary to maintain and increase their numbers. Many studies on ART for endangered feline species are underway using domestic cats as a model [1][2][3][4][5][10][11][12][13][14][15].…”

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confidence: 99%

The Qualities of Cryopreserved Epididymal Sperm Collected from Feline Epididymides Stored at Low Temperature

Toyonaga

Sato

Morita

et al. 2010

ABSTRACT. We observed the influences of low-temperature storage of the feline epididymis on the epididymal semen qualities before and after cryopreservation to identify the optimal duration for low-temperature storage of the epididymis. After excision, the feline epididymis was stored at 4  C for 0-72 hr and then subjected to epididymal sperm collection. When sperm from the refrigerated cauda epididymis were frozen and thawed, there was no significant difference in sperm motility between the 0-and 24-hr low-temperature storage groups, but sperm motility was significantly decreased in the 48-hr storage group. The above findings suggested that low-temperature storage of the epididymis until 24 hr is useful for frozen sperm collected from the feline cauda epididymis.KEY WORDS: cryopreservation, epididymal sperm, feline, refrigeration.J. Vet. Med. Sci. 72(6): 777-780, 2010 The total number of animals worldwide has decreased in many wildcat species, and various assisted reproductive technologies (ART) are necessary to maintain and increase their numbers. Many studies on ART for endangered feline species are underway using domestic cats as a model [1][2][3][4][5][10][11][12][13][14][15].In a previous study, we collected feline sperm from the cauda epididymis immediately after excision and performed intrauterine insemination of frozen semen (5  10 6 ) [14]. The mean sperm motility following freeze-thawing was 24.0  4.0% (SE), and the conception rate was only 27.3% (3/11). Two female cats delivered five and one kittens, respectively, and another one aborted on 30 days of gestation. This was our initial success rate achieved using epididymal frozen semen in cats. Our previous study is also the only one to report successful conception cases achieved using frozen feline epididymal semen thus far.The duration and temperature of storage before collection of sperm after excision of the epididymis have marked influences on semen qualities in various animal species [6][7][8][9]. In cats, Hay and Goodrowe [5] reported that semen qualities did not differ between sperm collected from the cauda epididymis immediately after excision and after 24-hr storage at 5C. Furthermore, Chatdarong et al. [3] compared the quality of caudal epididymal semen collect from the epididymis after storage for 2 and 4 days at 4C and reported that the sperm motility after storage for 2 days is significantly higher than that after storage for 4 days. Filliers et al. [4] observed that the qualities of semen from the feline epididymis stored in sterile physiological saline for 24 hr at 5C were good. However, Chatdarong et al. [3] and Filliers et al. [4] did not observe the semen quality immediately after excision. Tittarelli et al. [13] also stored the feline epididymis in sterile physiological saline or egg yolk-Tris for 24, 48 and 72 hr and observed the semen qualities. Sperm motility was apparently decreased at all storage time points, and egg yolk-Tris was suggested to be superior as a storage medium compared with physiological saline. Howev...

“…After incubation, the specimen was rinsed with cold PBS and air dried. In total, 200 sperm were assessed under fluorescent microscope at 1,000  magnification and classified as intact acrosome, reacted acrosome and loose acrosome [2]. The functional integrity of the sperm plasma membrane was assessed using a short hypo-osmotic swelling test (sHOST) [23].…”

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confidence: 99%

Cryopreservation of Boar Semen by Egg Yolk-Based Extenders Containing Lactose or Fructose is Better Than Sorbitol

Chanapiwat

Kaeoket

Tummaruk

2012

ABSTRACT. The present study determined the effect of different types of sugars (lactose, fructose, glucose and sorbitol) used in egg yolkbased extender on the post-thawed boar semen quality. Twenty-two ejaculates from 6 fertility-proven Yorkshire boars were cryopreserved by liquid nitrogen vapor method. Sperm motility, viability, acrosome integrity and intact functional plasma membrane were determined at 0, 2 and 4 hr after thawing. It was found that the lactose-based extender resulted in a higher percentage of post-thawed sperm motility, viability, intact acrosome and functional plasma membrane than sorbitol-based extender (P<0.05) and fructose-based extender yielded a higher post-thawed sperm motility and viability than sorbitol-based extender (P<0.05). It could be concluded that sorbitol was not an effective sugar for the cryopreservation in boar semen. Boar semen cryopreservation greatly facilitates the distribution of valuable and desirable genes because the frozen semen can be transported over a long distance; and a stock of frozen semen enables the use of boar that is dead or ill [3]. However, the use of frozen-thawed (FT) boar semen is limited due to the low fertility outcomes compared to the extended fresh semen [9]. During cryopreservation, both physical and chemical factors including the rapid change in temperature or thermal stress, oxidative stress and osmotic stress lead to the damage of the sperm plasma membrane [19]. In general, the egg yolk-based freezing extender of boar semen consists of cryoprotectant, sugar, buffer and antibiotic [16]. Glycerol is the most common cryoprotectant used in the egg yolk-based semen extender for cryopreservation of the boar semen [14] and egg yolk is regarded as a non-permeable cryoprotectant. Sugar is mainly an energy source of the boar sperm. Furthermore, it protects the boar sperm from dehydration and intracellular ice formation during the semen freezing process [27]. Different types of sugar, e.g., trehalose, lactose, fructose, have been used in the freezing extender of boar semen [15,18].Recently, special interest on researches concerning with the energy utilization of the boar sperm have been noticed [13,15,18,20]. In general, the boar sperm is able to utilize a variety of substrates to obtain energy. Generally, monosaccharides are more common energy source used in extended fresh boar semen than disaccharides [20]. However, lactose (disaccharide) is commonly used for the cryopreservation of boar semen by many researchers [8,9,16,17]. In our previous studies [10,17] [24]. The stallion's cryopreserved sperms utilize sorbitol in the semen extender better than fructose and glucose [24]. In the boar, information associated with the effect of sugar types used in egg yolk-based semen extender on the FT semen qualities is limited. Therefore, the objective of the present study was to determine the effect of different sugar types (lactose, fructose, glucose and sorbitol) used in egg yolk-based semen extender on the sperm motility, sperm viability, acrosome integrity a...