scholarly journals Acrosomal integrity and capacitation are not influenced by sperm cryopreservation in the giant panda

Reproduction ◽  
2004 ◽  
Vol 127 (5) ◽  
pp. 547-556 ◽  
Author(s):  
R E Spindler ◽  
Y Huang ◽  
J G Howard ◽  
P Wang ◽  
H Zhang ◽  
...  

Sperm cryopreservation and artificial insemination are important management tools for giant panda breeding and the preservation of extant genetic diversity. This study examined the influence of freeze–thawing on sperm function, specifically capacitation. Sperm from nine giant pandas were assessed before and after rapid (− 40 and − 100 °C/min) cryopreservation by incubation in HEPES-buffered Ham’s F10 medium with and without the capacitation accelerators, 3-isobutyl-1-methylxanthine (IBMX) and dibutyryl cyclic AMP (dbcAMP). At 0, 3 and 6 h of exposure, aliquots were assessed for sperm motility traits and capacitation, defined as the proportion of sperm with intact acrosomes following exposure to solubilised zonae pellucidae (ursid or felid) or calcium ionophore subtracted from the proportion of sperm with intact acrosomes before exposure. Although mean±s.e.m. sperm motility post-thaw (56.1 ± 3.9% at 0 h) was less (P < 0.05) than pre-freeze (71.7 ± 6.0%), there was no difference (P > 0.05) in the proportion of acrosome-intact sperm (fresh, 93.0 ± 1.7% versus cryopreserved–thawed, 81.7 ± 4.7% at 0 h). Incidence of capacitation was greater (P < 0.05) in fresh sperm incubated with capacitation accelerators IBMX and dbcAMP (9 h: 50.9 ± 1.1) compared with fresh sperm incubated without accelerators (9 h: 41.2 ± 1.1%). Frozen–thawed sperm preincubated without accelerators underwent capacitation (49.6 ± 1.1%) to a greater extent (P < 0.05) compared with these fresh counterparts. Thawed samples with (9 h: 45.9 ± 1.4%) and without accelerators (9 h: 41.2 ± 1.1%) did not differ (P > 0.05) during the 9-h incubation. We conclude that giant panda spermatozoa (1) undergo capacitation in vitro with or without chemical accelerators and (2) withstand a rapid cryopreservation protocol, including retaining normal acrosomal integrity and functional capacitation ability.

2015 ◽  
Vol 27 (1) ◽  
pp. 128 ◽  
Author(s):  
I. A. Plourde ◽  
H. L. Bateman ◽  
W. F. Swanson

Propagation of genetically diverse felid populations would benefit from more effective assisted reproduction strategies, including enhanced methods for sperm cryopreservation. In felids, sperm cryopreservation has been improved by substituting soy-lecithin for egg yolk in cryomedium (Vick et al. 2012 Theriogenology 78, 2120–2128). In other species, such as elephants (Kiso et al. 2012 Reprod., Fert. Dev. 24, 1134–1142) and cattle (Purdy et al. 2004 Cryobiology 48, 36–45), the addition of cholesterol-loaded cyclodextrins (CLC) to sperm before freezing has been shown to produce superior cryopreservation results. In this study, our objectives were to (1) assess cholesterol content of cat sperm membranes and capacitation status following incubation with CLC; (2) evaluate post-thaw sperm motility, acrosome status, and fertility in vitro following CLC treatment and freezing in a soy-based cryomedium; and (3) conduct a preliminary assessment of cholesterol content in nondomestic cat sperm. Freshly collected domestic cat sperm (n = 2 males, 3–4 ejaculates/male) were incubated with CLC (0, 1.5, or 3.0 mg mL–1), and cholesterol levels were measured using an Amplex Red Cholesterol Assay. Sperm aliquots from each CLC concentration were treated with calcium ionophore (2 μM, 30 min) during in vitro incubation and stained with fluorescein isothiocyanate/PNA to evaluate induced acrosomal loss. To assess post-thaw parameters, cat sperm treated with CLC were frozen in straws using soy-lecithin cryomedium, thawed, and cultured in vitro over time. To evaluate fertility, oocytes were collected laparoscopically from gonadotropin-treated domestic cats (n = 7 females, 147 oocytes total) and inseminated with low numbers of thawed-frozen sperm pretreated with 0 or 1.5 mg mL–1 CLC. Data were analysed using ANOVA and mean differences assessed with Fisher l.s.d. or chi-squared analysis. Sperm cholesterol levels were increased (P < 0.05) after exposure to both 1.5 and 3.0 mg mL–1 CLC. Prefreeze motility was decreased (P < 0.05) and capacitation was delayed at 3.0 mg mL–1 CLC relative to treatment with 0 or 1.5 mg mL–1 CLC. Both post-thaw motility and percentage of acrosome intact sperm were reduced (P < 0.05) with the highest CLC concentration, but results were similar (P > 0.05) for 0 and 1.5 mg mL–1 CLC. Fertilization percentages did not differ (P > 0.05) between treatment groups (0 CLC, 33.3%, 25/75; 1.5 mg mL–1 CLC, 26.4%, 19/72). Preliminary results from a single cheetah (Acinonyx jubatus) and single fishing cat (Prionailurus viverrinus) suggest that sperm membrane cholesterol may be lower compared to the domestic cat. Cholesterol content appeared to increase in both species after exposure to 1.5 mg mL–1 CLC. In summary, our findings suggest CLC treatment increased cholesterol content of felid sperm membranes. The higher CLC concentration was detrimental to sperm motility, capacitation, and post-thaw sperm traits. The lower CLC concentration did not improve post-thaw sperm function in domestic cats.Research supported by the Procter & Gamble Wildlife Conservation Scholarship Program.


2006 ◽  
Vol 18 (7) ◽  
pp. 767 ◽  
Author(s):  
Rebecca E. Spindler ◽  
Huang Yan ◽  
JoGayle Howard ◽  
Wang PengYan ◽  
Zhang Hemin ◽  
...  

Natural breeding of giant pandas in captivity is compromised, making artificial insemination and spermatozoa cryopreservation essential for genetic management. This study examined the influence of freeze–thawing on traditional parameters such as motility and spermatozoon functionality, specifically decondensation in vitro. Giant panda spermatozoa were assessed before and after rapid cryopreservation (4°C to –130°C over 2 min) in liquid nitrogen vapour. Spermatozoa pre-incubated in medium for 6 h were co-incubated with cat zonae (2 zonae μL–1) for 30 min to effect capacitation and an acrosome reaction. Spermatozoa were then mixed with mature cat oocyte cytoplasm (2 cytoplasm μL–1) for 4 h and evaluated for decondensation. Frozen spermatozoa were less motile (P < 0.05) than fresh counterparts immediately post-thawing, but not after 6 h incubation. There were more (P < 0.05) spermatozoa with completely diffused chromatin post-thaw (10.4 ± 1.3%; mean ± s.e.m.) compared to fresh counterparts (5.1 ± 1.0%). However, there was no overall difference (P > 0.05) in the incidence of decondensation between fresh (4 h, 69.8 ± 5.9%) and thawed (4 h, 71.5 ± 4.9%) spermatozoa after exposure to cat oocyte cytoplasm. It is concluded that the ‘rapid’ method now used to cryopreserve giant panda spermatozoa has little impact on spermatozoon decondensation.


1997 ◽  
Vol 272 (3) ◽  
pp. R793-R799 ◽  
Author(s):  
A. Cases ◽  
J. M. Stulak ◽  
Z. Katusic ◽  
E. Villa ◽  
J. C. Romero

It is well known that hemoglobin binds nitric oxide (NO) and produces a pronounced vasoconstriction in isolated arteries. However, it is debatable whether such an effect takes place in whole animals, because hemoglobin also catalyzes the formation of prostaglandins from arachidonic acid. Short-term studies were performed to evaluate the effects induced by intravenous infusion of cross-linked hemoglobin (XL-Hb) on blood pressure (BP) and renal, iliac, and mesenteric flows, and on renal function in six anesthetized dogs. A similar volume-matched expansion with 6% dextran was used as a control (n = 6). Glomerular filtration rate (GFR), urinary flow, and total and fractional sodium excretion were measured before and after XL-Hb or dextran infusion to evaluate possible renal function changes. XL-Hb administration resulted in a 29% elevation in BP and a significant decrease of blood flow (30-37%) to the three vascular beds. XL-Hb did not alter GFR or sodium excretion, despite the increase in BP. In contrast, the administration of dextran did not significantly alter BP but induced a significant increase (6-13%) of blood flow in the three vascular beds. These changes were accompanied by threefold increases in urinary flow and sodium excretion without alterations in GFR. The binding effect of XL-Hb on NO was studied in isolated renal arteries in organ chambers. These in vitro studies showed that XL-Hb blunted the endothelium-mediated vasodilator response to calcium ionophore A-23187 and to acetylcholine. Our results demonstrate that XL-Hb administration is followed by hypertension, vasoconstriction, and blunted natriuresis. All these effects are compatible with the scavenging effect on NO attributed to XL-Hb.


2006 ◽  
Vol 18 (3) ◽  
pp. 373 ◽  
Author(s):  
Khongsak Thiangtum ◽  
William F. Swanson ◽  
JoGayle Howard ◽  
Wanchai Tunwattana ◽  
Dakara Tongthainan ◽  
...  

Conservation of the fishing cat, a threatened south-east Asian felid, could benefit from effective ex situ genetic management and breeding programmes, including the use of assisted reproduction. The aims of the present study were to: (1) characterise basal seminal traits of fishing cats in Thailand zoos; and (2) investigate the effect of cryopreservation on sperm motility, acrosomal integrity and in vitro function. Seminal traits were evaluated in electroejaculates collected from eight males. Spermatozoa were diluted in n-tris(hydroxymethyl)-methyl-2-aminoethanesulfonic acid Tris (TEST)-yolk buffer (TYB) without glycerol, then diluted further with TYB with glycerol (4% final concentration) at either 25°C or after slow cooling to 5°C and frozen in straws over liquid nitrogen vapour. After thawing, sperm function was assessed by insemination of viable domestic cat oocytes. Fishing cat ejaculates averaged (± s.e.m.) 43.6 ± 14.2 × 106 motile spermatozoa with 33.5 ± 6.8% normal sperm morphology. Semen processing had a negligible effect (P > 0.05) on sperm motility and acrosomal integrity, but values were reduced (P < 0.05) after thawing. All thawed samples fertilised domestic cat oocytes, with 62.1% (36/58) of mature oocytes cleaving. Glycerol addition at 5°C resulted in higher (P < 0.05) post-thaw motility and intact acrosomes than glycerol addition at 25°C. In conclusion, good-quality ejaculates can be obtained from Thai fishing cats and their spermatozoa exhibit adequate function after cryopreservation for in vitro fertilisation procedures.


2007 ◽  
Vol 19 (5) ◽  
pp. 652 ◽  
Author(s):  
R. M. Santymire ◽  
P. E. Marinari ◽  
J. S. Kreeger ◽  
D. E. Wildt ◽  
J. G. Howard

The endangered black-footed ferret (Mustela nigripes) has benefited from artificial insemination; however, improved sperm cryopreservation protocols are still needed. The present study focused on identifying factors influencing gamete survival during processing before cryopreservation, including: (1) the presence or absence of seminal plasma; (2) temperature (25°C v. 37°C); (3) type of medium (Ham’s F10 medium v. TEST yolk buffer [TYB]); (4) cooling rate (slow, rapid and ultra-rapid); and (5) the presence or absence of glycerol. Seminal plasma did not compromise (P > 0.05) sperm motility or acrosomal integrity. Sperm motility traits were maintained longer (P < 0.05) at 25°C than at 37°C in Ham’s or TYB, but temperature did not affect (P > 0.05) acrosomal integrity. Overall, TYB maintained optimal (P < 0.05) sperm motility compared with Ham’s medium, but Ham’s medium maintained more (P < 0.05) intact acrosomes than TYB. Slow cooling (0.2°C min–1) was optimal (P < 0.05) compared to rapid cooling (1°C min–1), and ultra-rapid cooling (9°C min–1) was found to be highly detrimental (P < 0.05). Results obtained in TYB with 0% or 4% glycerol were comparable (P > 0.05), indicating that 4% glycerol was non-toxic to ferret sperm; however, glycerol failed to ameliorate the detrimental effects of either rapid or ultra-rapid cooling. The results of the present study demonstrate that the damage observed to black-footed ferret spermatozoa is derived largely from the rate of cooling.


Author(s):  
Narendra Kumar ◽  
B. Rai ◽  
Chetna Gangwar ◽  
S. A. Lone ◽  
Anshuman Kumar ◽  
...  

The present study was designed to determine the effect of different levels of egg-yolk on freezability of Jakhrana buck semen. Six healthy Jakhrana bucks (BW=30 ± 2kg, age=12 ± 0.5 month) were used for semen collection. These bucks were maintained under semi-intensive system at Jakhrana Unit of C.I.R.G. Makhdoom, Mathura. A total of 48 ejaculates (6 bucks × 8 replicates) were collected twice a week using artificial vagina. Each ejaculate was divided into 4 groups (G1, G2, G3 and G4). The G1, G2, G3 and G4 were extended with Tris-egg yolk-citric acid- fructose-glycerol (TEYCFG) extenders containing 5, 10, 15 and 20% egg yolk level, respectively. Each ejaculate was evaluated for sperm motility, viability, abnormality, and hypo-osmotic swelling (HOS) response and acrosome integrity before and after freezing. At pre-freeze stage no significant (P>0.05) difference in sperm motility and viability was found among all groups. Sperm abnormality was significantly (P<0.05) higher in G4 as compared to other groups (G1, G2, G3). The HOS response and acrosomal integrity was significantly (P<0.05) higher in G1, G2 and G3 as compared to G4. However, no significant (P>0.05) difference was observed in HOS response and acrosomal integrity among G1, G2 and G3. At post thaw stage, sperm motility, viability and HOS response was significantly (P<0.05) higher in G1 and G2 as compared to G3 and G4. Sperm abnormality was significantly (P<0.05) lower in G2 as compared to other groups. The acrosomal integrity was significantly (P<0.01) higher in G1 and G2 as compared to G3 and G4. It is concluded that 10% egg yolk in Tris based extender may be the best for successful cryopreservation of Jakhrana buck semen.


2017 ◽  
Vol 14 (4) ◽  
pp. 1309-1313
Author(s):  
Y. Al-Anazi ◽  
M. G. Al-Mutary ◽  
M. M. Alfuraiji ◽  
M. Al-Ghadi ◽  
A. R. Al-himaidi ◽  
...  

The aim of this work was to investigate the impacts of ram breed on in vitro embryo development from fresh or frozen semen. Semen was collected from Najdi and Naimi rams and frozen; the mass and progressive motility of the spermwere assessed in each trial before and after freezing. Then, 970 oocytes in six replicates were fertilized with fresh and frozen semen in vitro. Different stages of sheep embryos were recorded. There were no significant differences in mass and progressive sperm motility of fresh or frozen ram semen between Najdi and Naimi,but there were significant differences between frozen and fresh semen within each breed. Our results showed significant (P<0.05) differences in 2-cell stage, 4-cell stage, 8-cell stage, morula, fragmented embryos, cleavage and blastocyst rates in the frozen semen group compared to fresh semen group in both breeds. In addition, significant (P<0.05) differencesbetween the two breeds were shown in 8-cell and16-cell embryonic stages.In conclusion, there were slight breed effects on the efficiency of in vitro development of sheep embryos.


2017 ◽  
Vol 29 (1) ◽  
pp. 137
Author(s):  
A. Moresco ◽  
H. L. Bateman ◽  
J. Newsom ◽  
W. F. Swanson

Historically, semen banking in felids has required sample collection via electroejaculation followed by sperm freezing in straws over LN2 vapor. Recent modifications include urethral catheterization of males treated with α-2 agonists for semen recovery and vitrification of cat sperm by suspension in a sucrose-based cryomedium and direct pelleting into LN2. In combination, these latter methods greatly simplify semen cryopreservation in cats but protocols need to be optimized for applied usage. In the present study, our goal was to assess the effect of 2 variables—pellet volume and thawing temperature—on post-thaw sperm motility, acrosome status, and in vitro fertility. Semen was collected from 3 males (3 ejaculates/male) via urethral catheterization under dexmedetomidine-ketamine anaesthesia. Sperm were diluted in Feline Optimized Culture Medium (FOCM), centrifuged (8 min; 300 × g), and resuspended in a soy-lecithin-based vitrification medium (with 0.2 M sucrose). After a 5-min equilibration, sperm was vitrified in 2 volumes (20 or 30 µL) by direct pipetting into LN2. Sperm pellets were thawed in FOCM at 1 of 2 temperatures (37 or 55°C) and the 4 treatment groups (20 µL-37°C, 20–55, 30–37, 30–55) assessed for percentage of progressively motile and acrosome intact sperm. To assess sperm function, additional 30-µL pellets were thawed at 37 or 55°C, and recovered sperm were used to inseminate in vitro-matured domestic cat oocytes (n = 10–25/ejaculate). At 48 h post-insemination, oocytes and embryos were fixed (1% NBF). Hoechst fluorescent stain (#33342) was used to evaluate embryo cleavage and maturation status of unfertilized ova. Sperm motility and acrosomal integrity percentages were analysed by ANOVA, and oocyte cleavage proportions were analysed by chi-squared. Mean (± SEM) progressive sperm motility post-thaw did not differ (P > 0.05) among treatments (38 ± 8, 34 ± 7, 41 ± 7, 32 ± 7% for 20 µL-37°C; 20–55, 30–37, and 30–55, respectively). Similarly, acrosomal integrity did not differ (P > 0.05) among treatments (26 ± 4, 25 ± 4, 17 ± 3, 17 ± 2% for 20 µL-37°C, 20–55, 30–37, and 30–55, respectively). Oocyte cleavage proportions did not differ (P > 0.05) between thawing temperatures for total inseminated oocytes but, after correcting for oocyte maturation status, was higher (P < 0.01) for samples thawed at 55°C (60%, 67/112) compared with 37°C (39%, 52/133). In summary, although variations in pellet volume and thawing temperature had minimal effect on sperm motility or acrosome status immediately post-thaw, sperm function appeared to be enhanced when vitrified pellets were thawed at a higher temperature. In vitro fertility success (~60% embryo cleavage) is comparable to values reported by our laboratory with conventionally collected and frozen cat semen, suggesting these newer methods may be suitable for applied usage in felids. This study was funded by the Institute of Museums and Library Services.


Sign in / Sign up

Export Citation Format

Share Document