Freezing techniques in horses involve the controlled application of low temperatures to preserve equine biological samples, tissues, or cells for research and clinical purposes. These techniques are employed in various contexts, including the preservation of semen for artificial insemination, the storage of embryos for breeding programs, and the conservation of genetic material. The process typically involves the use of cryoprotectants to prevent ice crystal formation, which can damage cellular structures. Research in this area focuses on optimizing freezing protocols to enhance viability and functionality post-thaw. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and outcomes of freezing techniques in equine science.
Pasch L, Schmidt A, King W.The use of autologous blood processing tools including platelet-rich plasma (PRP) devices is increasingly widespread in veterinary medicine. In equine reproduction, a number of studies have explored the effects of intrauterine infusion of PRP on persistent mating-induced endometritis. Artificial insemination with thawed frozen semen incites an intrauterine inflammatory response and we sought to extend the applications of intrauterine PRP to normal mares being inseminated with frozen semen. We investigated a subset of our normal breeding population to observe the clinical effects of prebreeding...
Gaitskell-Phillips G, MartÃn-Cano FE, Ortiz-RodrÃguez JM, Silva-RodrÃguez A, Gil MC, Ortega-Ferrusola C, Peña FJ.The identification of stallions and or ejaculates that will provide commercially acceptable quality post-thaw before cryopreservation is of great interest, avoiding wasting time and resources freezing ejaculates that will not achieve sufficient quality to be marketed. Our hypothesis was that after bioinformatic analysis, the study of the stallion sperm proteome can provide discriminant variables able to predict the post-thaw quality of the ejaculate. At least three ejaculates from 10 different stallions were frozen following a split sample design. Half of the ejaculate was analyzed as a fresh ...
Wilsher S, Rigali F, Kovacsy S, Allen WT.Successful vitrification of equine expanded blastocysts requires collapse of the blastocoele cavity using a micromanipulator-mounted biopsy pipette on an inverted microscope. Such equipment is expensive and requires user skill. Objective: To develop a manual method of blastocoele collapse prior to vitrification using commercial products. Methods: In vivo experiment. Methods: Seventy-nine Day 7 or 8 embryos were measured and graded. Twenty were vitrified following micromanipulator-assisted puncture and aspiration before being used to validate commercial human vitrification and warming kits cont...
Alves NC, Diniz SA, Viegas RN, Cortes SF, Costa ED, Freitas MM, Martins-Filho OA, Araújo MSS, Lana ÂMQ, Wenceslau RR, Lagares MA.The aim of this study was to improve the quality of frozen-thawed equine sperm by the addition of caffeine to it. Semen from nine stallions was frozen and different concentrations of caffeine (3, 5 and 7.5 mM) were added to frozen-thawed semen. The sperm kinetic parameters, membrane functionality and integrity, and acrosome integrity and spontaneous acrosome reacted sperm were evaluated with a computer-assisted sperm analysis, a hypoosmotic swelling test and epifluorescent microscopy, respectively. Nitrite and hydroperoxide concentrations of frozen-thawed semen were measured using spectrophot...
Diaz-Jimenez M, Rota A, Dorado J, Consuegra C, Pereira B, Camillo F, Panzani D, Fanelli D, Tesi M, Monaco D, Hidalgo M.Sperm vitrification has been recently developed, but fertility trials have not been performed yet in equine species. In this study, a new warming technique for vitrified donkey semen was developed and the uterine inflammatory response and fertility were compared to conventional freezing. In Experiment 1, sperm was vitrified in straws and warmed in 3 ml of extender or in a water bath at: 37 °C/30 s; 43 °C/10 s; and 60 °C/5 s. Sperm motility, plasma and acrosome membranes and DNA integrity were compared between treatments. In Experiment 2, jennies were inseminated twice (500 Ã...
Vieira LA, Matás C, Torrecillas A, Saez F, Gadea J.Seminal plasma (SP) plays a crucial role in sperm protection and functionality. However, the effect of SP on the sperm cryopreservation is dependent on the stallion and SP composition. The use of epididymal spermatozoa incubated in the presence of SP could help the identification of the components of SP that are able to confer protection upon the spermatozoa during freezing. The aims of this study were (i) to identify SP components involved in the potential protection of epididymal spermatozoa during the freeze-thawing process and (ii) to identify and evaluate the proteins likely related to sp...
Novello G, Segabinazzi LGTM, Lisboa FP, Canuto LE, Freitas-Dell'Aqua CP, Dell'Aqua JA, Canisso IF.This study compared the postthaw semen parameters of stallions with high and low body condition score (BCS) and evaluated associations between body morphometric parameters and postthaw semen parameters. Twenty stallions were split into Low BCS (BCS<7, n = 11) and High BCS (BCS ≥7, n = 9) groups, and underwent a complete morphometric analysis (e.g., neck scores and circumference, crest neck height, body weight, and height), and subcutaneous body fat thickness (SFT) at the tail head, withers, shoulders, and retroperitoneal space. A fasted oral sugar test (OST) was conducted on all stallio...
Bubenickova F, Postlerova P, Simonik O, Sirohi J, Sichtar J.Seminal plasma (SP) is the natural environment for spermatozoa and contains a number of components, especially proteins important for successful sperm maturation and fertilization. Nevertheless, in standard frozen stallion insemination doses production, SP is completely removed and is replaced by a semen extender. In the present study, we analyzed the effects of the selected seminal plasma protein groups that might play an important role in reducing the detrimental effects on spermatozoa during the cryopreservation process. SP proteins were separated according to their ability to bind to hepar...
Ebel F, Vallejos A, Gajardo G, Ulloa O, Clavel E, RodrÃguez-Gil JE, RamÃrez-Reveco A.The aim of this study was to evaluate seasonal changes in basic parameters of sperm quality and freezability behaviour of ejaculates from 10 fertile heavy draft stallions. A total of 140 ejaculates were collected, processed and evaluated during both the breeding (September-November) and non-breeding seasons (April-June). Fresh semen was evaluated for volume, concentration, total spermatozoa per ejaculate, plasma membrane integrity and total sperm motility. Cryopreserved samples were evaluated for plasma membrane integrity and sperm motility by the CASA system, and for the freezability index (F...
Kumar P, Mehta JS, Ravi SK, Dedar RK, Purohit GN, Legha RA, Tripathi BN, Talluri TR.The present study was conducted with the hypothesis that addition of cholesterol to the extender would stabilize the sperm membranes by increasing the cholesterol-to-phospholipid (C:P) ratio and would result in an improved post-thaw semen quality and reduce oxidative stress in the jack (Martina franca) semen. Forty-eight ejaculates from six jacks were collected and analyzed for the present study. The freshly collected semen sample of each jack stallion was divided into five equal fractions after addition of the primary extender without cholesterol-loaded cyclodextrin (CLC) (C) and with 1, 1.5,...
Bahrami A, Divar MR, Azari M, Kafi M.In the present study, we aimed to evaluate the possible protective effects of the nicotinic acid (NA) at three concentrations (10, 20, and 40Â mM) on the equine cooled and frozen-thawed spermatozoa quality markers including viability, plasma membrane or acrosome integrity, DNA fragmentation, lipid peroxidation, and total oxidant levels. We also evaluated the effects of NA on preservation of the post-thaw sperm quality after 6Â hours of cold storage before freezing. Five stallions were used for semen collections. The current experiment was repeated six times using pooled semen samples from two ...
Ferrer MS, Canisso IF, Ellerbrock RE, Podico G, Lister BN, Hurley DJ, Kline K, Palomares RA.Freezing cooled-transported semen allows veterinarians and breeders to collect and process the semen of stallions on farm, and then ship the semen to a semen freezing center. There, however, is a lack of standardization of shipping and freezing protocols. The objectives were to optimize and simplify protocols to freeze cooled-shipped semen. In Experiment 1, cooled-transported semen was centrifuged at room temperature or 5 °C before freezing. Sperm variables (motility, membrane integrity, acrosome integrity, membrane fluidity) were evaluated before and after freezing. Centrifugation temperat...
Dominguez EM, Moreno-Irusta A, Rodriguez MB, Salamone DF, de Arruda RP, Losinno L, Giojalas LC.The successful use of assisted reproduction techniques (ART) depends in part on the sperm physiological status. Several sperm selection procedures have been applied to improve quality of sperm population when using the ART. There has previously been development of a Sperm Selection Assay (SSA) for humans which is based on the attraction of capacitated sperm by chemotaxis towards progesterone (P), resulting in an enriched sperm population with an optimal physiological status similar to capacitated spermatozoa, with these cells having very little DNA fragmentation and optimal concentrations of r...
Fukuda K, Kuroda T, Tamura N, Mita H, Kasashima Y.Platelet-rich plasma (PRP) therapy has been widely applied in various medical fields including humans and horses. This study aimed to establish an optimal activation method to stably and reproducibly maximize the concentrations of platelet-derived growth factor-BB (PDGF-BB) and transforming growth factor-β1 (TGF-β1) contained in equine PRP. Autologous PRP was prepared from 11 Thoroughbreds. For the activation test, PRP was activated by either a single freeze-thaw cycle (Fr) or adding calcium and autologous serum containing thrombin (Ca). PDGF-BB and TGF-β1 concentrations in Fr, Ca, nonactiv...
Herrera C.Embryo cryopreservation is normally performed with great success in species like humans and cattle. The large size of in vivo-derived equine embryos and the presence of a capsule-impermeable to cryoprotectants-have complicated the use of embryo cryopreservation in equine reproduction. A breakthrough for this technique was obtained when large equine embryos could be successfully cryopreserved after collapsing the blastocoel cavity using a micromanipulation system. High pregnancy rates have been obtained when vitrification is used in combination with embryo collapse.
Oldenhof H, Wolkers WF, Sieme H.In modern livestock breeding, cryopreserved semen is routinely used for artificial insemination. Sperm cryopreservation allows for long-term storage of insemination doses and secures reproduction at a desired time point. In order to cryopreserve semen, it needs to be carefully processed to preserve its vital functions after thawing. In this chapter, we describe the processes involved in cryopreservation of bull, stallion, and boar sperm. These include preparation of diluents, dilution of sperm in primary and freezing extender, slow cooling from room temperature to 5 °C, packaging of insemina...
Catalán J, Llavanera M, Bonilla-Correal S, Papas M, Gacem S, RodrÃguez-Gil JE, Yeste M, Miró J.The aim of this study was to evaluate whether red-light stimulation increases the longevity and resilience of cryopreserved stallion sperm to withstand post-thaw incubation for 120 min. Sixteen frozen straws of 0.5 mL from eight stallions were used. Samples were cryopreserved, thawed through incubation at 38 °C for 30 s and divided into the control and samples exposed to red-light using a triple LED photo-activation system (wavelength: 620-630 nm). Three irradiation protocols consisting of different light-dark-light intervals (1-1-1, 2-2-2 and 3-3-3 min) were tested. Sperm quality param...
Alamaary MS, Haron AW, Hiew MWH, Ali M.Present study aimed to investigate the effect of adding antioxidants, cysteine and ascorbic acid on the levels of glutamic oxaloacetic transaminase (GOT), glutamic-pyruvate (GPT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and γ-glutamyl transpeptidase (GGT) enzymes of post-thawed stallion sperm. Ten ejaculates were collected each from four healthy stallions and cryopreserved using HF-20 freezing extender containing either 0 mg/ml cysteine or ascorbic acid, 0.5 mg/ml cysteine and 0.5 mg/ml ascorbic acid. All samples in freezing extender containing cysteine or ascorbic acid or ...
Castro R, Morales P, Parraguez VH.In this work, we investigated the influence of age and seasonality on sperm motility and DNA fragmentation in post-thawing semen from Chilean Purebred Stallions (CPS), a horse breed presenting the oldest genealogy record in South America with an interesting reproductive industry. Despite that semen from aged CPS is frozen all year round, there is a lack of studies characterizing the breed semen freezability in accordance with age and seasonality. Twenty fertile CPS were grouped into the young group, the middle group, and the aged group. Ten ejaculates from each stallion were obtained by using ...
Gáspárdy A, Renkó E, Somoskői B, Bába A, Cseh S.The objective of this study was to compare the efficiency of artificial insemination (AI) carried out with frozen and fresh, diluted and chilled semen under field conditions. One hundred and twenty-nine mares of different breeds were included in the study. Eighty-one out of the 107 mares inseminated with fresh, chilled semen got pregnant. Seven pregnant mares aborted and 74 foals were born. Out of the 22 mares inseminated with frozen semen, 17 mares got pregnant. Two mares out of the 17 pregnant mares aborted and finally 15 healthy foals were born. No difference was found between the two group...
Hu K, Stewart AJ, Yuen KY, Hinrichsen S, Dryburgh EL, Bertin FR.Determination of plasma adrenocotrophic hormone (ACTH) concentration (endogenous or thyrotropin-releasing hormone [TRH] stimulation test) is the most commonly used diagnostic test for pituitary pars intermedia dysfunction (PPID) in horses. Because ACTH is unstable, samples often are frozen to be shipped to laboratories or to allow for batch analysis of research samples. However, the effect of multiple freeze-thaw cycles on equine ACTH is unknown. Objective: To determine the effects of multiple freeze-thaw cycles on immunoreactive ACTH concentration. Methods: Twenty-eight horses ranging from 10...
X-ray structures of homopolymeric human L-ferritin and horse spleen ferritin were solved by freezing protein crystals at different time intervals after exposure to a ferric salt and revealed the growth of an octa-nuclear iron cluster on the inner surface of the protein cage with a key role played by some glutamate residues. An atomic resolution view of how the cluster formation develops starting from a (μ -oxo)tris[(μ -glutamato-κO:κO')](glutamato-κO)(diaquo)triiron(III) seed is provided. The results support the idea that iron biomineralization in ferritin is a process initiating at the l...
Canesin HS, Ortiz I, Rocha Filho AN, Salgado RM, Brom-de-Luna JG, Hinrichs K.Equine embryo vitrification is still not a well-established technique in equine practice. Notably, little work has been done on the effect of the warming system on viability of vitrified embryos. Our goal was to evaluate the effect of warming without cryoprotectants on in vitro - produced (IVP) embryo viability in culture, quality assessment parameters, and pregnancy after transfer. Equine IVP blastocysts were vitrified using commercial embryo vitrification media and a semi-closed vitrification device. In Exp. 1, we evaluated two warming temperatures (room temperature, RT, ∼22 °C; and 38Â...
De Coster T, Velez DA, Van Soom A, Woelders H, Smits K.Invitro embryo production has evolved rapidly in the horse over the past decade, but blastocyst rates from vitrified equine oocytes remain quite poor and further research is needed to warrant application. Oocyte vitrification is affected by several technical and biological factors. In the horse, short exposure of immature oocytes to the combination of permeating and non-permeating cryoprotective agents has been associated with the best results so far. High cooling and warming rates are also crucial and can be obtained by using minimal volumes and open cryodevices. Vitrification of invivo-matur...
Hinrichs K.Methods for holding of oocytes and embryos during shipment as well as for their cryopreservation can greatly aid equine reproductive management. Oocytes can be held at room temperature overnight or at cooler temperatures for two nights without affecting maturation or embryo development after intracytoplasmic sperm injection. In contrast, methods for cryopreservation of equine oocytes that support high rates of embryo development have not yet been established. Equine embryos may be held overnight at temperatures from 5°C to 19°C without reduction in viability, but longer holding periods, or h...
Squires E.Numerous reproductive technologies have been developed in the past several decades, which have dramatically changed the way mares are bred. This review will focus on embryo recovery and transfer, cooled-shipped embryos, embryo freezing, oocyte freezing, oocyte collection and transfer, intracytoplasmic sperm injection (ICSI), and sexed semen. Embryo transfer procedures have been constant for many years and the costs have not changed. The major change has been the ability to store embryos at 5Â C for 12-24Â hours and transport them to recipient stations. Embryo freezing has become more common us...
Prell MJ, McCue PM, Moffett PD, Graham JK.Breeding mares with cryopreserved semen requires specialized equipment for storage and thawing and more intensive mare management. The objectives of this study were (1) evaluate the longevity of frozen stallion semen once it had been thawed, extended, and maintained at 5°C for 48 hours in a passive cooling container, and (2) determine fertility potential of frozen semen that had been thawed, extended, and used to inseminate mares after 24 hours of cooled storage. Eight ejaculates were collected and aliquots were cooled in either INRA96 and CryoMax LE minus cryoprotectant at a concentration ...
de Albuquerque Lagares M, Silva GCD, Cortes SF, Luz SB, de Resende AC, Alves NC, Wenceslau RR, Stahlberg R.During semen cryopreservation, the sensitivity of equine sperm to oxidative stress is increased by the eliminated seminal plasma. Thus, antioxidant addition to the semen extender can be helpful to the sperm survival after freezing and thawing. This work aimed to test whether coenzyme Q10 (CoQ10) added in different concentrations to the INRA 82 freezing extender has antioxidant function on equine sperm to improve its fertilizing ability. Semen samples from five stallions were frozen with the extenders: (T1) INRA 82, control, (T2) T1+ 5 μM CoQ10, (T3) T1+ 25 μM CoQ10, and (T4) T1+ 50 μM Co...
Tharasanit T, Colleoni S, Galli C, Colenbrander B, Stout TA.Vitrifying oocytes is a potentially valuable means of preserving the female germ line, but significantly compromises oocyte developmental competence. This study examined the hypothesis that the cumulus complex protects the oocyte during vitrification. Vitrified-warmed immature cumulus oocyte complexes (COCs) were labelled with a plasma membrane impermeant DNA marker (ethidium homodimer-1) to examine the percentage and location of dead cumulus cells, and to investigate the effect of the proportion of dead cells (+1,+2 or +3) on the success of in vitro maturation (IVM). Further, oocytes were lab...
Blottner S, Warnke C, Tuchscherer A, Heinen V, Torner H.The study compared quality and freezability of stallion semen during breeding and non-breeding seasons. Ejaculates were collected twice per week from four stallions during May (n = 24) and December (n = 24). The semen was mixed with skim milk extender, centrifuged and resuspended in fresh extender. Aliquots of this sperm suspension were separated from extender and diluted in TALP medium for sperm evaluation or with cryoextender (type "Gent" or a combination of Triladyl and skim milk). Samples of 0.5ml were cryopreserved in straws using a programmed freezer. Parameters of sperm quality were eva...
Maclellan LJ, Carnevale EM, Coutinho da Silva MA, Scoggin CF, Bruemmer JE, Squires EL.The objectives were to compare embryo development rates after transfer into inseminated recipients, vitrified thawed oocytes collected from super-stimulated versus non-stimulated mares. In vivo matured oocytes were collected by transvaginal, ultrasound guided follicular aspiration from super-stimulated and non-stimulated mares 24-26 h after administration of hCG. Oocytes were cultured for 2-4 h prior to vitrification. Cryoprotectants were loaded in three steps before oocytes were placed onto a 0.5-0.7 mm diameter nylon cryoloop and plunged directly into liquid nitrogen. Oocytes were thawed and...
Muñoz PM, Ferrusola CO, Lopez LA, Del Petre C, Garcia MA, de Paz Cabello P, Anel L, Peña FJ.Stallion-to-stallion variability in the quality of cryopreserved ejaculates postthaw affects the commercial acceptability of frozen semen and thus is a major constraint for the equine industry. In recent years, the molecular mechanisms associated with sperm damage during cryopreservation have become better understood. Identification of the freezability of the ejaculates before the freezing process is initiated will have a major impact on the equine industry. We studied three markers of oxidative stress in sperm, including 8-iso-PGF2alpha, 8-OH guanosine, and 4-hydroxynonenal (4-HNE); the prese...
Carneiro JAM, Canisso IF, Bandeira RS, Scheeren VFC, Freitas-Dell'Aqua CP, Alvarenga MA, Papa FO, Dell'Aqua JA.This study aimed to evaluate the antioxidant properties of coenzyme Q10 (CoQ10) during cryopreservation of semen obtained from stallions having good and bad semen freezing ability (GFA vs. BFA, respectively). Forty ejaculates (n = 20 stallions) were split into five centrifugation and five freezing extenders containing different concentrations of CoQ10 (0, 25, 50, 75 and 100 μmols/L). If CoQ10 was added to the centrifugation extender, the freezing extender had no CoQ10 added; similarly, if CoQ10 was added to the freezing extender, the centrifugation extender had no CoQ10. Semen cryoprese...
Pillet E, Labbe C, Batellier F, Duchamp G, Beaumal V, Anton M, Desherces S, Schmitt E, Magistrini M.Egg yolk is normally used as a protective agent to freeze semen of equine and other species. However, addition of egg yolk in extenders is not without disadvantages and the demand to find cryoprotective alternatives is strong. The objective of this study was to test the cryoprotective capacities of liposomes composed of egg yolk phospholipids. Two experiments were conducted: 1) the first to determine the optimal composition and concentration of liposomes to preserve post-thaw motility and membrane integrity of spermatozoa; 2) the second to assess in vivo the cryoprotective capacities of these ...
Squires E.Numerous reproductive technologies have been developed in the past several decades, which have dramatically changed the way mares are bred. This review will focus on embryo recovery and transfer, cooled-shipped embryos, embryo freezing, oocyte freezing, oocyte collection and transfer, intracytoplasmic sperm injection (ICSI), and sexed semen. Embryo transfer procedures have been constant for many years and the costs have not changed. The major change has been the ability to store embryos at 5Â C for 12-24Â hours and transport them to recipient stations. Embryo freezing has become more common us...
Peña FJ, Gibb Z.The growing understanding of the mechanisms regulating redox homeostasis in the stallion spermatozoa, together with its interactions with energetic metabolism, is providing new clues applicable to the improvement of sperm conservation in horses. Based on this knowledge, new extenders, adapted to the biology of the stallion spermatozoa, are expected to be developed in the near future. The preservation of semen either by refrigeration or cryopreservation is a principal component of most animal breeding industries. Although this procedure has been successful in many species, in others, substantia...
Schurer J, Davenport L, Wagner B, Jenkins E.Fecal samples from wild and domestic carnivores are routinely frozen for three days at -80°C to kill eggs of Echinococcus spp., following recommendations from the World Health Organization (WHO) and World Organization for Animal Health (OIE). This is done to decrease the risk of zoonotic infection with these pathogenic cestodes. In addition, it is often necessary to freeze fecal samples collected for research prior to batch processing by a limited number of personnel, especially large numbers of samples or those collected in remote locations. The effect of freezing on the recovery of endopara...
Squires EL, Carnevale EM, McCue PM, Bruemmer JE.Recent studies demonstrated that zwitterionic buffers could be used for satisfactory storage of equine embryos at 5 degrees C. The success of freezing embryos is dependent upon size and stage of development. Morulae and blastocysts <300 microm can be slowly cooled or vitrified with acceptable pregnancy rates after transfer. The majority of equine embryos are collected from single ovulating mares, as there is no commercially available product for superovulation in equine. However, pituitary extract, rich in FSH, can be used to increase embryo recovery three- to four-fold. Similar to human medic...
Hu K, Stewart AJ, Yuen KY, Hinrichsen S, Dryburgh EL, Bertin FR.Determination of plasma adrenocotrophic hormone (ACTH) concentration (endogenous or thyrotropin-releasing hormone [TRH] stimulation test) is the most commonly used diagnostic test for pituitary pars intermedia dysfunction (PPID) in horses. Because ACTH is unstable, samples often are frozen to be shipped to laboratories or to allow for batch analysis of research samples. However, the effect of multiple freeze-thaw cycles on equine ACTH is unknown. Objective: To determine the effects of multiple freeze-thaw cycles on immunoreactive ACTH concentration. Methods: Twenty-eight horses ranging from 10...
Dordas-Perpinyà M, Yanez-Ortiz I, Sergeant N, Mevel V, Bruyas JF, Catalán J, Delehedde M, Briand-Amirat L, Miró J.ProAKAP4 is the precursor of AKAP4 (A-kinase Anchor protein 4), the main structural protein of the fibrous sheath of sperm. The amount of proAKAP4 reflects the ability of spermatozoa to maintain the flagellum activity and functionality up to the site of fertilization and is positively correlated with progressive motility in several mammalian species. The aim of this study was to investigate the relationship between proAKAP4 concentration with horse sperm motility descriptors and spermatic motile subpopulations. For this purpose, a total of 48 ejaculates from 13 different stallions were analyze...
Oldenhof H, Zhang M, Narten K, Bigalk J, Sydykov B, Wolkers WF, Sieme H.Nonviable freeze-dried sperm have intact chromatin and can be used for fertilization via intracytoplasmic sperm injection. Freeze-dried sperm preferably should be stored at 4°C or lower, because DNA damage accumulates during storage at room temperature. Disaccharides are known to protect biomolecules both during freezing and drying, by forming a glassy state. Their use is challenging because cellular membranes are normally impermeable for disaccharides. In the current study, we demonstrate that membrane impermeable compounds, including lucifer yellow and trehalose, are taken up by stallion sp...
Gavriliuc S, Stothart MR, Henry A, Poissant J.The development of next-generation sequencing technologies has spurred a surge of research on bacterial microbiome diversity and function. But despite the rapid growth of the field, many uncertainties remain regarding the impact of differing methodologies on downstream results. Sample storage temperature is conventionally thought to be among the most important factors for ensuring reproducibility across marker gene studies, but to date much of the research on this topic has focused on short-term storage in the context of clinical applications. Consequently, it has remained unclear if storage a...
Loomis PR.Recent acceptance of frozen semen as a method to produce registered foals by two of the worlds largest breed associations, the American Quarter Horse and American Paint Horse, has stimulated new interest in frozen semen technology. This review will: (a) attempt to identify the major impediments to the development of the frozen semen industry, (b) suggest alternative methods for marketing and application of frozen semen, and (c) present the results of a recent study in our laboratory. The objective of which was to compare pregnancy rates of insemination with cooled and frozen semen. Major imped...
Mislei B, Bucci D, Malama E, Bollwein H, Mari G.Oxidative stress is regarded as an important cause of sperm damage during cryopreservation. However, seasonal changes in oxidative status in unfrozen and frozen-thawed stallion sperm have not been well established. We tested the hypothesis that sperm ROS concentrations and lipid peroxidation change between breeding and non-breeding seasons and influence quality of unfrozen and frozen-thawed sperm. Eighteen ejaculates from six Warmblood stallions (8-21 y) known to be fertile, were collected in winter and summer and processed for freezing. After 90 min at +4 °C, some straws from each ejacu...
X-ray structures of homopolymeric human L-ferritin and horse spleen ferritin were solved by freezing protein crystals at different time intervals after exposure to a ferric salt and revealed the growth of an octa-nuclear iron cluster on the inner surface of the protein cage with a key role played by some glutamate residues. An atomic resolution view of how the cluster formation develops starting from a (μ -oxo)tris[(μ -glutamato-κO:κO')](glutamato-κO)(diaquo)triiron(III) seed is provided. The results support the idea that iron biomineralization in ferritin is a process initiating at the l...
Hoogewijs M, Rijsselaere T, De Vliegher S, Vanhaesebrouck E, De Schauwer C, Govaere J, Thys M, Hoflack G, Van Soom A, de Kruif A.Three experiments were conducted to evaluate the impact of centrifugation on cooled and frozen preservation of equine semen. A standard centrifugation protocol (600 x g for 10 min=CP1) was compared to four protocols with increasing g-force and decreased time period (600 x g, 1200 x g, 1800 x g and 2400 x g for 5 min for CP2, 3, 4, and 5, respectively) and to an uncentrifuged negative control. In experiment 1, the influence of the different CPs on sperm loss was evaluated by calculating the total number of sperm cells in 90% of the supernatant. Moreover, the effect on semen quality following ce...
van Eps AW.Digital hypothermia successfully reduces the severity of experimentally induced laminitis. Continuous-distal limb cryotherapy may be a useful technique in clinical cases that are at risk of developing laminitis. This article examines the effects of hypothermia on tissue as well as the rationale, and suggested protocols for the usage of distal limb cryotherapy in the prevention and treatment of laminitis.
Prutton JS, Kass PH, Watson JL, Pusterla N.The stability of equine adrenocorticotrophic hormone (ACTH) in blood samples is not fully known. The study objectives were to determine ACTH stability (1) in whole blood and plasma over 72 h at either 4 or 21 °C, and (2) in plasma frozen at either -20 or -80 °C over 30 days. Nine horses were sampled and ACTH concentration were measured after storage as whole blood or plasma, at 4, 21, -20 and -80 °C for up to 30 days. The ACTH concentration was significantly reduced at 24 h but remained stable when plasma was frozen at -20 and -80 °C for 30 days. Beyond 24 h, samples stored a...
Canisso IF, Carvalho GR, Morel MD, Ker PG, Rodrigues AL, Silva EC, Coutinho Da Silva MA.As mule production is often concentrated in remote areas of the world, a simplified semen cryopreservation protocol is required. Objective: To compare the seminal parameters of cryopreserved donkey semen in lactose-EDTA and lactose-yolk extenders and the fertility rates on horse mares. Methods: TRIAL 1: Sperm total and progressive motility, vigour (scale 0-5), morphology (major and minor defects) and plasma membrane integrity (HOST) were evaluated in 25 ejaculates from 5 donkey jacks immediately after collection (raw), after chilling to 5°C (chilled) and after freezing/thawing. The semen was ...
Olaciregui M, Gil L, Montón A, Luño V, Jerez RA, Martà JI.Any event that makes semen collection or mating impossible, such as death, castration, or injury, may terminate a stallion's breeding career. Fortunately, stallion sperm which are capable of fertilization can be harvested from the epididymis, and frozen for future use. However, the fertility of frozen-thawed epididymal sperm has been found to be lower than that of ejaculated sperm. Therefore, this study aimed to optimize the fertility of frozen epididymal stallion sperm by investigating the effects of different cryoprotectants and freezing protocols on sperm quality. Dimethylformamide was test...
Blommaert D, Sergeant N, Delehedde M, Donnay I, Lejeune JP, Franck T, Serteyn D.The quality of fresh or thawed sperm in stallions has been generally determined by the viability and total and progressive motility of the sperm. Today, the expression of ProAKAP4, a protein present in the flagellum of spermatozoa, appears to be an innovative and relevant functional marker to assess semen quality and male fertility. This study aims to compare the concentration of ProAKAP4 in the semen from 5 stallions frozen with two different extenders immediately after thawing (T0) and 4Â h post-thawing (T4). Viability, total and progressive motility were measured in parallel. Significant di...
Tharasanit T, Colenbrander B, Stout TA.Oocyte cryopreservation is a potentially valuable technique for salvaging the germ-line when a valuable mare dies, but facilities for in vitro embryo production or oocyte transfer are not immediately available. This study examined the influence of maturation stage and freezing technique on the cryopreservability of equine oocytes. Cumulus oocyte complexes were frozen at the immature stage (GV) or after maturation in vitro for 30 hr (MII), using either conventional slow freezing (CF) or open pulled straw vitrification (OPS); cryoprotectant-exposed and untreated nonfrozen oocytes served as contr...
Ortiz-Rodriguez JM, Balao da Silva C, Masot J, Redondo E, Gazquez A, Tapia JA, Gil C, Ortega-Ferrusola C, Peña FJ.The population of stallion spermatozoa that survive thawing experience compromised mitochondrial functionality and accelerated senescence, among other changes. It is known that stallion spermatozoa show very active oxidative phosphorylation that may accelerate sperm senescence through increased production of reactive oxygen species. Rosiglitazone has been proven to enhance the glycolytic capability of stallion spermatozoa maintained at ambient temperature. Thus, we hypothesized that thawed sperm may also benefit from rosiglitazone supplementation. Thawed sperm were washed and resuspended in Ty...
Squires EL, Keith SL, Graham JK.Although use of cryopreserved stallion spermatozoa is currently accepted by many breed registries, utilization of this technique remains limited due to poor fertility for some stallions. One reason for these results is osmotic stress that spermatozoa experiences when the cryoprotectant (glycerol) is added to the cells prior to freezing and removal from the cells after thawing. In an effort to minimize osmotic damage, alternative cryoprotectants, having lower molecular weights and greater membrane permeability than glycerol, were evaluated to determine their effectiveness for cryopreserving sta...
Tharasanit T, Colenbrander B, Stout TA.Horse embryos are rarely cryopreserved in practice because expanded blastocysts tolerate freezing poorly, and the embryo begins expanding very soon after entering the uterine cavity. This study examined the effects of freezing on cytoskeleton integrity, and investigated whether cell damage could be reduced using trypsin to thin the blastocyst capsule or cytochalasin-B (cyto-B) to stabilise the cytoskeleton. Sixty-nine embryos were recovered 7 days after ovulation and equilibrated in 10% glycerol, with or without pretreatment with 0.2% trypsin or 7.5 microg/ml cyto-B. Forty-two of the embryos w...
Catalán J, Yánez-Ortiz I, Tvarijonaviciute A, González-Aróstegui LG, Rubio CP, Barranco I, Yeste M, Miró J.The objective of this study was to determine the relationship of enzymatic (superoxide dismutase, SOD; glutathione peroxidase, GPX; catalase, CAT; and paraoxonase type 1, PON1) and non-enzymatic antioxidants (measured in terms of: Trolox equivalent antioxidant capacity, TEAC; cupric-reducing antioxidant capacity, CUPRAC; and ferric-reducing ability of plasma, FRAP), as well as the oxidative stress index (OSI) in seminal plasma (SP) with the resilience of horse sperm to freeze-thawing. Twenty-one ejaculates (one per individual) were collected and split into two aliquots: the first was used to h...
Hochi S, Kozawa M, Fujimoto T, Hondo E, Yamada J, Oguri N.The study was designed to examine the suitability of immature horse oocytes for vitrification. Immature oocytes derived from slaughtered horse ovaries were transferred to a vitrification solution (EFS; 40% ethylene glycol, 18% Ficoll, and 0.3 M sucrose in modified phosphate-buffered saline) directly (Groups 1 and 4) or were first exposed to 20% ethylene glycol solution for 10 min (Groups 2 and 5) or 20 min (Groups 3 and 6). Oocytes were handled at 20 degrees C (Groups 1, 2, and 3) or 30 degrees C (Groups 4, 5, and 6). After vitrification and warming, their viability was assessed by maturation ...
Gaitskell-Phillips G, MartÃn-Cano FE, Ortiz-RodrÃguez JM, Silva-RodrÃguez A, Gil MC, Ortega-Ferrusola C, Peña FJ.Although cryopreservation is widely used in animal breeding, the technique is still suboptimal. The population of spermatozoa surviving the procedure experiences changes attributed to alteration in their redox regulation. In order to expand our knowledge regarding this particular aspect, the proteome in fresh and frozen thawed aliquots of equine spermatozoa was studied to identify the proteins most severely affected by the procedure. If alteration of redox regulation is a major factor explaining cryodamage, proteins participating in redox regulation should be principally affected. Using a spli...