Centrifugal force assessment in ram sperm: identifying species-specific impact

Abstract Background Centrifugation is routinely employed in handling the ejaculates of some species, but it is not part of the commonly used protocols in ram. However, the development and implementation of new assisted reproductive technologies, alternative preservation models based on washing sperm from a cellular ageing-accelerating substance such as the seminal plasma, and basic studies in spermatology is associated with the use of centrifugation. This requires a specific evaluation of the centrifugation protocols considering the species-specific relationship with the potential damage produced by this procedure. No previous studies have determined the effect of different centrifugation forces on ram sperm. Therefore, we aimed to assess the performance of three centrifugal forces (600×g, 3000×g, and 6000×g for 10 min at room temperature) and their effects on ram sperm motility and functionality. Results Sperm motility and functionality parameters were assessed at 0 h and after 2 h of incubation at 37 °C. As expected, a higher cell packaging degree was obtained at high centrifugation forces (P ≤ 0.0001). Cell packaging was unstable at all centrifugal forces. Thus, there was a high cell resuspension rate after less than 2 min. Regarding sperm quality, there was a change in movement pattern of 3000×g and 6000×g centrifuged sperm after 2 h of incubation at 37 °C, characterized by an increase in rapid progressive motility, linearity, straightness, and beat frequency, and a decrease in medium progressive motility, curvilinear velocity, path velocity, and head lateral amplitude. Non-significant differences were obtained among the different treatments concerning the total viability. However, we observed a significant increase (P ≤ 0.05) in the percentage of viable apoptotic sperm in the samples centrifuged at 6000×g at 0 h. Conclusions Centrifugal forces equal to or greater than 3000×g induced some deleterious effects in ram sperm quality, and lower forces did not provide a successful cell packaging degree.

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163 EVALUATION OF VIABILITY OF BULL SEMEN COLLECTED BY ELECTRO-EJACULATION USING COMMERCIAL SEMEN EXTENDER AND 2 CULTURE MEDIA AT CONTROLLED ROOM TEMPERATURE

Reproduction Fertility and Development ◽

10.1071/rdv29n1ab163 ◽

2017 ◽

Vol 29 (1) ◽

pp. 190

Author(s):

A. M. Raseona ◽

O. A. Ajao ◽

L. D. Nethengwe ◽

L. R. Madzhie ◽

T. L. Nedambale ◽

...

Keyword(s):

Sperm Motility ◽

Assisted Reproductive Technologies ◽

Culture Media ◽

Reproductive Technologies ◽

Sperm Viability ◽

Progressive Motility ◽

Bull Semen ◽

Significant Difference ◽

Semen Extender ◽

Motility Rate

Preservation of semen is an important process to ensure that semen quality is sufficient for assisted reproductive technologies. The aim of this study was to evaluate the viability of bull semen collected by electro-ejaculation using commercial semen extender and 2 modified culture media stored at controlled RT (24°C) for 72 h. Two Nguni bulls were used for semen collection; after collection, the semen was evaluated macroscopically for volume, pH, and colour, and microscopically for sperm motility, viability, and morphology. Uncontaminated semen samples with progressive motility >70% and morphological defects <20% were pooled after collection before being aliquoted into 3 extenders, namely Triladyl, modified Ham’s F10, and TCM-199 culture media, at a dilution ratio of 1:4 and then stored at controlled RT (24°C). Sperm motility rate was analysed using the computer-aided sperm analyser after 0, 24, 48, and 72 h of storage. Sperm morphology and viability was performed after staining the sperm cells with spermac and nigrosine-eosin stain, respectively. The study was replicated 4 times and data were analysed using ANOVA. Triladyl had a higher sperm viability rate (41.3%) and total motility rate (96.3%) for 72 h (P < 0.01) compared with the 2 modified culture media, Ham’s F10 (26.5 and 86.8%) and TCM-199 (25.0 and 86.7%), respectively. However, Ham’s F10 had higher progressive motility rate (37.8%) as compared with the other extenders, TCM-199 (31.7%) and Triladyl (23.4). There was no significant difference (P > 0.05), in viability rate between Ham’s F10 (26.5%) and TCM-199 (25.0%). No significant difference (P > 0.05) in straight line velocity was observed for the three extenders. Furthermore, no significant difference was observed in total sperm abnormalities, except for reacted acrosomes and absent tails (P > 0.05), between the 2 Nguni bulls. Nguni semen can be preserved in Triladyl or modified Ham’s F10 and TCM-199 culture media stored at 24°C and stay viable for 72 h. Triladyl proved to be the best suitable extender of the 3 extenders, showing higher sperm viability and total motility rate as compared with Ham’s F10 and TCM-199 modified culture media.

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From One Ejaculate to Another: Transference of Sperm Traits via Seminal Plasma Supplementation in the Ram

Biology ◽

10.3390/biology9020033 ◽

2020 ◽

Vol 9 (2) ◽

pp. 33

Author(s):

Christine Green ◽

Jessica P. Rickard ◽

Simon P. de Graaf ◽

Angela J. Crean

Keyword(s):

Sperm Motility ◽

Seminal Plasma ◽

Perceived Risk ◽

Positive Relationship ◽

Assisted Reproductive Technologies ◽

Sperm Quality ◽

Reproductive Technologies ◽

Before And After ◽

The Difference ◽

Sperm Traits

Males can adjust sperm motility instantaneously in response to the perceived risk of sperm competition. The speed of this response suggests that sperm motility is regulated by changes in seminal plasma rather than changes in the sperm cells themselves. Hence, here we test whether inter-ejaculate variation in seminal plasma can be used to alter sperm quality prior to use in assisted reproductive technologies. We supplemented fresh ejaculates of Merino rams with seminal plasma collected from previous ‘donor’ ejaculates to test whether changes in sperm kinetics were related to the relative quality of donor to focal ejaculates. We found a positive relationship between the change in sperm traits before and after supplementation, and the difference in sperm traits between the donor and focal ejaculate. Hence, sperm motility can be either increased or decreased through the addition of seminal plasma from a superior or inferior ejaculate, respectively. This positive relationship held true even when seminal plasma was added from a previous ejaculate of the same ram, although the slope of the relationship depended on the identity of both the donor and receiver ram. These findings indicate that seminal plasma plays a key role in the control and regulation of sperm kinetics, and that sperm kinetic traits can be transferred from one ejaculate to another through seminal plasma supplementation.

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The use of insulin-like growth factor 1 improved the parameters of the seminogram in a patient with severe oligoasthenoteratozoospermia

SAGE Open Medical Case Reports ◽

10.1177/2050313x19834154 ◽

2019 ◽

Vol 7 ◽

pp. 2050313X1983415

Author(s):

José Arturo Mora Rodríguez ◽

Leonardo M Porchia ◽

Felipe Camargo ◽

Esther López-Bayghen

Keyword(s):

Growth Factor ◽

Assisted Reproductive Technologies ◽

Sperm Quality ◽

Sperm Concentration ◽

Reproductive Technologies ◽

Quality Parameters ◽

Intradermal Injection ◽

Sperm Parameters ◽

Insulin Like Growth Factor ◽

Progressive Motility

Male patients suffering from oligoasthenoteratozoospermia typically failed to achieve pregnancy, even with assisted reproductive technologies. Growth hormone and insulin-like growth factor 1 have been shown to regulate sperm quality parameters; therefore, the insulin-like growth factor 1 supplement could improve sperm parameters. Here, we determine the effect insulin-like growth factor 1 has on sperm parameters in a patient suffering from oligoasthenoteratozoospermia. A 47-year-old male was administered once a day 1.5 IU of insulin-like growth factor 1 by intradermal injection for 2 months. Seminogram analysis was performed before and after. Treatment with insulin-like growth factor 1 resulted in a 15.5-fold improvement in sperm concentration (1.1 × 106 vs 18.3 × 106 per mL), 71.4% change in volume (0.7 vs 1.2 mL), increased progressive motility (2% vs 43%), and the total volume of sperm with progressive motility (0% vs 23.6%). Here, we show that administering a daily dose of insulin-like growth factor 1 can improve sperm quality parameters.

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Morphologic analysis of sperm from two neotropical primate species: comparisons between the squirrel monkeys Saimiri collinsi and Saimiri vanzolinii

Zygote ◽

10.1017/s0967199416000411 ◽

2017 ◽

Vol 25 (2) ◽

pp. 141-148 ◽

Cited By ~ 2

Author(s):

Wlaisa V. Sampaio ◽

Karol G. Oliveira ◽

Danuza L. Leão ◽

Maria C. Caldas-Bussiere ◽

Helder L. Queiroz ◽

...

Keyword(s):

Sperm Motility ◽

Sperm Quality ◽

Reproductive Technologies ◽

Poor Quality ◽

Biological Information ◽

Primate Species ◽

Suitable Model ◽

High Quality ◽

Sperm Morphometry ◽

Species Specific

SummarySperm morphometry can be applied to identify different animal groups and species and to evaluate sperm quality. Furthermore, knowledge on species-specific differences will help to enhance biological information, as well as to develop efficient reproductive technologies. The aims in the present study were to describe sperm morphometry from the recently characterized species S. collinsi and S. vanzolinii, to verify if the morphometric sperm patterns are similar or different between both species, and to determine if the sperm morphometry is affected by the levels of sperm defects using the S. collinsi as a model. Semen was collected from S. collinsi (n = 10) and S. vanzolinii (n = 2) monkeys, and sperm was submitted to morphological analysis. From the 10 samples from S. collinsi, five presented sperm of poor quality and two subgroups were formed for this species, i.e. high and poor quality sperm. Data on sperm motility and vigour were analysed, as well morphometric parameters on sperm head and tail. It was observed the normal morphometry was correlated with high quality sperm. Poor quality sperm presented smaller and 7% more ellipticity in their head, when compared with high quality sperm. Sperm from S. vanzolinii presented larger head than those from S. collinsi, but tail lengths were similar. Sperm morphometry can be used as a complementary tool to predict sperm motility and vigour for the S. collinsi species, and S. collinsi appear as a suitable model for S. vanzolinii.

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The effect of the breeding season, cryopreservation and physiological extender on selected sperm and semen parameters of four ferret species: implications for captive breeding in the endangered black-footed ferret

Reproduction Fertility and Development ◽

10.1071/rd08075 ◽

2009 ◽

Vol 21 (2) ◽

pp. 351 ◽

Cited By ~ 9

Author(s):

G. van der Horst ◽

R. M. Kitchin ◽

M. van der Horst ◽

R. W. Atherton

Keyword(s):

Breeding Season ◽

Sperm Motility ◽

Captive Breeding ◽

Assisted Reproductive Technologies ◽

Sperm Quality ◽

Reproductive Technologies ◽

Semen Parameters ◽

Breeding Cycle ◽

Sperm Characteristics ◽

Motion Characteristics

In the present investigation, comparative baseline information on selected sperm characteristics of ejaculate spermatozoa of the domestic (Mustela putorius furo), fitch (Mustela sp.) and black-footed ferrets (Mustela nigripes) and the Siberian polecat (Mustela eversmanni) are presented. The main emphasis was to establish differences and similarities among these species in relation to semen and sperm quality during the breeding season, in cryopreservation success and in supporting sperm motility in different extenders or physiological media. The results confirm that most sperm morphology abnormalities were evident during the beginning of the breeding cycle in all four species. No significant interspecies differences were apparent in the sperm attributes examined, for all sampling months during the breeding season. Moreover, all species exhibited comparable patterns of reproductive seasonality. Cryopreservation suppressed sperm characteristics equally in all species studied. Ejaculate spermatozoa of closely related ferret species shared many similar motion characteristics using computer-aided sperm motility analysis. These results suggest that the basic sperm physiology of the ferret species under examination is very similar. Disparate to the interspecies comparisons, there were significant differences for most sperm motion parameters when spermatozoa of any of the ferrets were compared in different extenders. Assisted reproductive technologies developed for use in domestic ferret, fitch ferret or Siberian polecat may be successfully applied to captive breeding of the black-footed ferret using semen during any of the functional breeding months.

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115 SPERM CRYOPRESERVATION IN TRAGELAPHINE ANTELOPES

Reproduction Fertility and Development ◽

10.1071/rdv18n2ab115 ◽

2006 ◽

Vol 18 (2) ◽

pp. 166

Author(s):

G. Wirtu ◽

C. E. Pope ◽

A. Cole ◽

R. A. Godke ◽

D. L. Paccamonti ◽

...

Keyword(s):

Sperm Motility ◽

San Diego ◽

Assisted Reproductive Technologies ◽

Sperm Quality ◽

Skim Milk ◽

Reproductive Technologies ◽

Epididymal Spermatozoa ◽

Greater Kudu ◽

C 30 ◽

Cold Pack

As an integral aspect of our program to develop assisted reproductive technologies in tragelaphine antelopes, we have been evaluating the effects of various extenders on cryosurvival of spermatozoa. Semen was collected by electroejaculation (EEJ) from an eland (Taurotragus oryx, n = 14 EEJs) and a bongo (Tragelaphus euryceros, n = 7 EEJs) male during sedation and standing restraint in a hydraulic chute. Epididymal spermatozoa were collected from the proximal vas deferens, and distal epididymides recovered from four common eland bulls after elective castration at the Hattiesburg Zoo, Mississippi (age = 46 months) and the San Diego Wild Animal Park, California (ages = 18, 20, and 23 months). Testes from a bongo (age = 6.5 yr) and a greater kudu bull (Tragelaphus strepsiceros, age = 7.5 yr) at the Audubon Nature Institute were recovered and processed immediately postmortem. Kudu, bongo, and the Hattiesburg eland testes were transported at ambient temperature whereas the testes from San Diego elands were shipped overnight in a cold-pack container. Sperm processing was done at room temperature (RT = 23°C) in HEPES-buffered Tyrode's solution. Four extenders containing 7% glycerol were evaluated: Biladyl®, TEST Yolk buffer (TYB), Beltsville extender (BF5F), and skim milk. For freezing, sperm samples were initially extended and gradually cooled to 4°C before sequential addition of extender containing glycerol at 4°C; the procedure was then modified by addition of the glycerol fraction at RT before the sample was cooled to 4°C. Spermatozoa were vapor-frozen in 0.5 mL straws placed 5 cm above liquid nitrogen before storage at −196°C. Straws were thawed in a water bath (38°C, 30 s) to evaluate cryosurvival. All eland and bongo electroejaculation procedures produced spermatozoa, although sperm quality varied. Ejaculate volume averaged 5.4 ± 1.2 mL and 3.7 ± 1.1 mL in the bongo and the eland, respectively. Sperm motility at collection, after cooling, and after freezing in the different extenders is presented in Table 1. No immediate decline in sperm motility was observed after adding glycerol to samples, whether at 23°C or 4°C. Bongo spermatozoa lost more motility during freezing than during cooling (15.0 ± 4.4 vs. 5.8 ± 2.0%; P = 0.006); whereas, in eland, motility loss during cooling and freezing was similar (25.3 ± 16.2 vs. 21.1 ± 7.7; P = 0.44). The present results indicate that cooling and freezing tolerance of spermatozoa in tragelaphine antelopes is influenced by species, extender type, and temperature at which a cryoprotectant is added. Table 1. Cryosurvival of ejaculated or epididymal spermatozoa of three antelope species in different extenders

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Intrinsic and Extrinsic Factors Predicting the Cumulative Outcome of IVF / ICSI Treatment

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.b1007.1292s19 ◽

2019 ◽

Vol 9 (2S) ◽

pp. 269-273 ◽

Cited By ~ 1

Keyword(s):

Assisted Reproductive Technologies ◽

Sperm Quality ◽

Reproductive Technologies ◽

Process Time ◽

Success Rates ◽

Embryo Viability ◽

Extrinsic Factors ◽

Response Level ◽

Female Population ◽

Incident Cases

Infertility rates in India becoming increased in last decade principally due to the urbanization conditions and the lifestyle habits. It is giving alarm by continuously reporting the progress in incident cases of infertility amongst the young Indian adults of both male and female population. Among the various Assisted Reproductive Technologies (ART) available today in the treatment of infertility, In Vitro Fertilization (IVF) is found to be the most applicable treatment method of choice. This involves the administration of different hormones and drugs to treat infertility. In the present scenario technically IVF treatment process is tedious, laborious, high cost and most importantly success rates reported to be very low (20-30%). The prediction of IVF success rates is becoming an important scientific knowledge and practice, which helps both the doctor and the candidate couple to know about the conditions hence to take the right decision. The accurate prediction of the IVF success rate is really a challenging task in obstetrics and gynecology medicine. The success rates of the IVF depends on the various factors such as Intrinsic factors i.e, Genetic predisposition, Age, Body mass Index, Hormonal balance, Embryo viability, Sperm quality, Endometriosis and overall patient’s response level of the candidate couple and the Extrinsic factors such as Medical equipment technology, Treatment methods, Personal experiences of clinicians and embryologists, Process time, Stress due to the lifestyle etc.

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P–050 The effectiveness of the platelet-rich plasma treatment of men with severe oligoasthenoteratozoospermia

Human Reproduction ◽

10.1093/humrep/deab130.049 ◽

2021 ◽

Vol 36 (Supplement_1) ◽

Author(s):

O Somova ◽

H Ivanova ◽

N Sotnyk ◽

K Kovalenko ◽

I Feskova

Keyword(s):

Male Infertility ◽

Sperm Motility ◽

Testosterone Level ◽

Assisted Reproductive Technologies ◽

Platelet Rich Plasma ◽

Sperm Concentration ◽

Free Testosterone ◽

Reproductive Technologies ◽

Positive Effects ◽

Free Testosterone Level

Abstract Study question To evaluate the effect of platelet-rich plasma (PRP) testicular injections on spermogram parameters of men with severe oligoasthenoteratozoospermia (OAT). Summary answer The PRP testicular injections have beneficial effects on spermatogenesis and enhance sperm concentration and motility in infertile men with OAT. What is known already The use of PRP therapy in assisted reproductive technologies is debatable. Despite the recent evidence of its positive effects in promoting endometrial and follicular growth, data from clinical studies are limited. There are only a few papers on the effectiveness of PRP therapy in the treatment of male infertility and sexual dysfunction. In more detail, the influence of PRP on spermatogenesis was carried out only on experimental animals. Although the mechanisms of its action have not yet been clarified, it is assumed that PRP, containing many biologically active molecules, realizes its effect through the tissue regeneration and cell proliferation. Study design, size, duration This prospective study included 68 men (34.6±5.2) years old with severe OAT (≤4 million/ml, motility ≤30%, normal sperm morphology ≤1%) receiving hormonal and antioxidant (AO) therapy during 6 months before in vitro fertilization cycles. 33 of them were injected once with autologous PRP (0.5 ml in each testicle). Spermogram and testosterone level were analyzed before the treatment and in 3, 4 and 6 months after it. Participants/materials, setting, methods: Sperm concentration, motility and morphology in ejaculate of 33 men of PRP group were compared with those in the group of 35 men without PRP within 6 months of starting the treatment. Total and free testosterone level were measured in blood serum. PRP was prepared by centrifuging the patient’s own blood in the anticoagulant-containing tubes. The final concentration of platelets in the obtained sample was 950.000 – 1.250 000 cells in 1 ml. Main results and the role of chance 4 months after the PRP injection, sperm concentration and motility increased in 18 of 33 men of the PRP group compared with the baseline (before the treatment) – 4.2 (1.0; 6.9) vs 1.4 (0.1; 3.4) mln/ml (p < 0.05) and 36.7 (30.6; 45.8) vs 17.7 (6.7; 28.2)% respectively (p < 0.05).The maximum increase in sperm motility (but not in sperm concentration!) was observed in 24 men in 6 months – 49.6 (39.6; 56.4)% (p < 0.05). Percent of morphologically normal spermatozoa in ejaculate slightly increased only in 12 men in that time period from 0–1% to 1–2%. The total testosterone level was 2.4 times higher than the baseline (31.6±7.2 vs 13.2±4.3 nmol/l, p < 0.05), the free testosterone level was 1.8 times higher (14.5±3.5 vs 7.9±3.0 pgl/ml, p < 0.05). Unlike the PRP group, in the group of men without PRP treatment, the sperm parameters did not changed compared with the baseline in 4 months after the starting hormonal and AO treatment. A significant increase of sperin concentration was observed only in 17 of 35 patients in 6 months. Sperm motility and percent of morphologically normal spermatozoa after the treatment did not differ from the baseline. Changes in the testosterone levels were similar to changes in PRP group. Limitations, reasons for caution Only young and middle-aged men were considered in the study. Large randomized controlled studies are required to confirm the PRP therapy efficacy and safety of f various fertility disorders. There are also no standardized protocols for PRP preparation. Wider implications of the findings: PRP therapy may have great potential for the treatment of male infertility and improving spermatogenesis. Optimization of methods of PRP preparation and dosage of testicular injections can enhance reproductive outcomes in assisted reproductive technologies. Trial registration number Not applicable

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154 A method of oviductal semen deposition for use in the goat

Reproduction Fertility and Development ◽

10.1071/rdv32n2ab154 ◽

2020 ◽

Vol 32 (2) ◽

pp. 203

Author(s):

N. Buzzell ◽

S. Blash ◽

K. Miner ◽

M. Schofield ◽

J. Pollock ◽

...

Keyword(s):

Assisted Reproductive Technologies ◽

Sperm Quality ◽

Sperm Concentration ◽

The United States ◽

Reproductive Technologies ◽

Poor Quality ◽

Implant Removal ◽

Suitable Alternative ◽

Midline Laparotomy ◽

Post Surgery

The objective of this study was to investigate a method of oviducal semen deposition as a strategy for producing offspring from poor-quality cryopreserved goat sperm. Invitro fertilisation (IVF) and AI are common assisted reproductive technologies used in small ruminants, but they have varied results in the goat. The use of poor-quality cryopreserved-thawed sperm (<50% live/dead ratio at post-thaw) can decrease the rate of success. These procedures were performed in the month of November in Central Massachusetts in the United States (42° N). Seven 10-year-old dairy goats (Saanen, Toggenburg, and Alpine breeds) were synchronised and superovulated using a progesterone implant on Day 0, a prostaglandin injection at Day 7, two daily injections of 36mg of FSH ~12h apart on Days 12-15, and progesterone implant removal on Day 14 followed by an injection of 50µg of gonadotrophin-releasing hormone. Sperm deposition was performed on Day 17 (72 h after implant removal). The animals were anaesthetised using a standardised protocol, intubated, and maintained using isoflurane, and sterile prep was performed before a midline laparotomy procedure. Straws from a single ejaculate from a transgenic founder that was cryopreserved using a commercial two-step glycerol-egg yolk-based extender were used. A straw from this collection was post-thawed 30 days after collection and, using a commercial live/dead stain, 67% live sperm was determined. The optimal type of sperm prep and sperm concentration is unknown and may be dependent on sperm quality. Therefore, different gradient preps using Vitrolife SpermGrad at three volumes (1.5 (used on two animals), 1.0, and 0.5mL) as well as two volumes of IVF Bioscience Bovine BO-SemenPrep (4.0mL (used on two animals) and 2.0mL) were used. All five pellets were diluted in 1.0mL of IVF Bioscience Bovine BO-IVF media. Sperm concentrations ranging from 75×106 to 27×106 spermmL−1 were deposited into one oviduct; then, a 10:1 dilution was performed and 7.5×106 to 2.7×10 spermmL−1 were deposited into the contralateral oviduct. The depositions were performed just proximal to the uterotubal junction in a volume of 0.1mL of diluent via a tuberculin syringe attached to a 20-gauge needle. Two days following the procedure, oviducts were flushed postmortem from three of the seven randomly selected goats. All three had fertilised embryos, and nineteen 8-cell embryos were retrieved. Three of these embryos were surgically transferred to the distal uterine horn of a suitable recipient. The recipient became pregnant and produced a single offspring. The remaining four of seven goats were killed 41 days post-surgery. Two of the four goats were pregnant, with one carrying one fetus and the other carrying five fetuses. Further studies are needed to optimise this method, but these initial results indicate that oviducal semen deposition directly into the oviduct proximal to the uterotubal junction may be a suitable alternative for producing offspring from suboptimal cryopreserved-thawed goat sperm.

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Sperm output and body condition are maintained independently of hibernation in an endangered temperate amphibian

Reproduction Fertility and Development ◽

10.1071/rd18073 ◽

2019 ◽

Vol 31 (4) ◽

pp. 796 ◽

Cited By ~ 1

Author(s):

Sinlan Poo ◽

Kristin M. Hinkson ◽

Edward Stege

Keyword(s):

Body Condition ◽

Assisted Reproductive Technologies ◽

Sperm Quality ◽

Reproductive Technologies ◽

Treatment Groups ◽

History Of ◽

Unexpected Findings ◽

Sperm Output ◽

Wyoming Toad ◽

Number Of Cells

Hibernation is an integral part of the life history of species living in seasonal environments. However, our knowledge about the link between hibernation and reproductive success in amphibians remains limited, which poses an obstacle for critical conservation efforts. To fill this gap, we quantified the effects of captive hibernation on sperm quality, sperm quantity and body condition in an endangered anuran, the Wyoming toad (Anaxyrus baxteri), and used naturally hibernated wild toads as a standard for comparison. We hypothesised that hibernation is essential for optimal sperm output but is detrimental to body condition. Sperm collection was performed using assisted reproductive technologies for both captive and wild toads. Contrary to our hypotheses, no differences were observed in sperm metrics (total number of cells, concentration, motility and viability) or in body condition across captive treatment groups (0, 30 or 60 days of hibernation). Moreover, no difference was found between sperm metrics of captive toads and wild toads. These unexpected findings suggest that hibernation may not be an essential process for spermiation in A. baxteri while using exogenous hormones, and illustrate the potential of temperate amphibians to adapt to varying environmental conditions during winter months.

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