Topic:Cryopreservation

Impact of Seminal Plasma Antioxidants on DNA Fragmentation and Lipid Peroxidation of Frozen-Thawed Horse Sperm.
Antioxidants (Basel, Switzerland)    March 6, 2024   Volume 13, Issue 3 322 doi: 10.3390/antiox13030322
Catalu00e1n J, Yu00e1nez-Ortiz I, Torres-Garrido M, Ribas-Maynou J, Llavanera M, Barranco I, Yeste M, Miru00f3 J.Cryopreservation is a stressful process for sperm, as it is associated with an increased production of reactive oxygen species (ROS). Elevated ROS levels, which create an imbalance with antioxidant capacity, may result in membrane lipid peroxidation (LPO), protein damage and DNA fragmentation. This study aimed to determine whether the membrane LPO and DNA fragmentation of frozen-thawed horse sperm relies upon antioxidant activity, including enzymes (superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) and paraoxonase type 1 (PON1)); non-enzymatic antioxidant capacity (Trolo...
Freezing Stallion Semen-What Do We Need to Focus on for the Future?
Veterinary sciences    February 2, 2024   Volume 11, Issue 2 65 doi: 10.3390/vetsci11020065
Al-Kass Z, Morrell JM.Artificial insemination (AI) is used frequently in the breeding of sport horses, apart from Thoroughbreds. Most AIs are carried out with cooled semen rather than frozen semen because of the difficulties in identifying a protocol that is suitable for freezing most ejaculates and the necessity to inseminate close to ovulation because of the short life of the thawed spermatozoa. More widespread use of frozen semen would improve biosecurity, allow greater choice of stallions, and offer more flexibility when managing deliveries of semen to the stud. It would even decrease the amount of antibiotics ...
Freezing of equine semen is influenced by exposure time and concentration of the cryoprotectant glycerol.
Cryo letters    October 26, 2023   Volume 44, Issue 4 234-239 
Fracaro PL, Corcini CD, Souza Gatti NL, Filho JS, Acosta IB, Filho JS, Hartwig FP, Rosa Curcio BD, Varela Junior AS.Glycerol is a cryoprotectant widely used in the freezing of mammalian semen, but no study has demonstrated its optimum concentration and the appropriate exposure time for equine species. Objective: To demonstrate that the exposure time (15, 30, 45, 60, 75 and 90 min) versus concentration (2, 3, 4 and 5%) of the cryoprotectant glycerol influences the freezing success of equine semen. Methods: The ejaculate of 12 stallions were frozen in different glycerol concentrations following different exposure times. The thawed sperm was evaluated for kinetic parameters using a Computer Assisted Semen Anal...
Effect of different manual puncture methods on donkey embryo before vitrification.
Theriogenology    September 15, 2023   Volume 214 134-140 doi: 10.1016/j.theriogenology.2023.09.010
Li N, Dai S, Wu H, Zhang F, Song S, Guo Y, Wang S, Chang S, Zeng S.The application of embryo recovery and transfer technology in the donkey industry is far lower than that of horses and cattle. Sometimes the recovered embryos could not be transferred in time, which required embryo cryopreservation. The embryo cryopreservation technology is more conducive to the preservation and transportation of recovered embryos with excellent genetic traits. However, this technique for donkey embryos is not efficient and needs further optimization. The objective of this study was to evaluate the effect of different manual puncture methods on the viability and pregnancy rate...
Continuous digital hypothermia for prevention and treatment of equine acute laminitis: A practical review.
Veterinary journal (London, England : 1997)    July 26, 2023   106016 doi: 10.1016/j.tvjl.2023.106016
Lavado RA, Lewis J, Montgomery JB.Laminitis is a severely debilitating and life-threatening condition that occurs as a consequence of different primary triggering factors. Continuous digital hypothermia (CDH) is recommended in horses at risk of, or diagnosed with, acute laminitis due to its several physiological and biochemical alterations that may be positive for the prevention and early treatment of the condition, representing a low risk of adverse effects. Modulation of the inflammatory response, profound vasoconstriction, and prevention of tissue damage are the most notable protective effects of cryotherapy on the lamellae...
Shipping duration and temperature influence the characteristics of cryopreserved horse semen stored in different shipping devices for up to 14 days.
Animal reproduction science    July 23, 2023   Volume 256 107307 doi: 10.1016/j.anireprosci.2023.107307
El-Shalofy A, Gautier C, Khan Y, Aurich J, Aurich C.This study aimed to investigate the effects of storing horse semen either in a dry shipper (≤ -150 °C) or on dry ice (≤ -78 °C) for up to 14 days. A total of 264 frozen semen straws from male horses (n = 8) stored in liquid nitrogen were transferred on day 0 (d0) to a dry shipper or a dry ice styrofoam box. On d1, d3, d7, d10, and d14, straws from the dry shipper and dry ice were returned to the liquid nitrogen container. Semen was evaluated by CASA for total (TMot), progressive motility (PMot) and sperm velocity parameters, by fluorescence microscopy for percentage of membrane-intac...
Heterologous Seminal Plasma Reduces the Intracellular Calcium and Sperm Viability of Cryopreserved Stallion Spermatozoa.
Biopreservation and biobanking    July 19, 2023   doi: 10.1089/bio.2022.0197
Talluri TR, Kumaresan A, Paul N, Elango K, Raval K, Nag P, Legha RA, Pal Y.Despite the vital role of seminal plasma (SP) in maintaining sperm function and aiding gamete interaction in many species, SP is usually removed before cryopreservation of stallion sperm to improve cryosurvival of sperm. The present study assessed if the vital sperm functional parameters of genetically superior stallions producing poor quality semen can be enhanced by the supplementation of heterologous SP from the stallion producing high quality semen. Spermatozoa from poor quality semen producing stallions were divided into three aliquots: two aliquots were supplemented with SP obtained from...
Investigation of optimal procedures for storage and use of plasma samples suitable for gene doping tests.
Journal of equine science    June 12, 2023   Volume 34, Issue 2 21-27 doi: 10.1294/jes.34.21
Tozaki T, Ohnuma A, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Takahashi Y, Nagata SI.Gene doping, which is prohibited in horseracing and equestrian sports, can be performed by introducing exogenous genes, known as transgenes, into the bodies of postnatal animals. To detect exogenous genes, a method utilizing quantitative polymerase chain reaction (qPCR) with a hydrolysis probe was developed to test whole blood and plasma samples, thereby protecting the fairness of competition and the rights of stakeholders in horseracing and equestrian sports. Therefore, we aimed to develop sample storage methods suitable for A and B samples in gene doping tests using blood. For sample A, suff...
Transcriptomics Reveal Molecular Differences in Equine Oocytes Vitrified before and after In Vitro Maturation.
International journal of molecular sciences    April 7, 2023   Volume 24, Issue 8 6915 doi: 10.3390/ijms24086915
Angel-Velez D, Meese T, Hedia M, Fernandez-Montoro A, De Coster T, Pascottini OB, Van Nieuwerburgh F, Govaere J, Van Soom A, Pavani K, Smits K.In the last decade, in vitro embryo production in horses has become an established clinical practice, but blastocyst rates from vitrified equine oocytes remain low. Cryopreservation impairs the oocyte developmental potential, which may be reflected in the messenger RNA (mRNA) profile. Therefore, this study aimed to compare the transcriptome profiles of metaphase II equine oocytes vitrified before and after in vitro maturation. To do so, three groups were analyzed with RNA sequencing: (1) fresh in vitro matured oocytes as a control (FR), (2) oocytes vitrified after in vitro maturation (VMAT), a...
Carboxymethylchitosan with medium-molecular-weight affects kinectics and acrosome of stallion sperm after freezing/thawing.
Journal of equine veterinary science    March 30, 2023   Volume 126 104489 doi: 10.1016/j.jevs.2023.104489
de Moura TCM, Arruda LCP, Cahu00fa TB, Bezerra RS, Carneiro GF, Guerra MMP.Semen cryopreservation ensures the storage of stallion genetics for an unlimited time. The improvement of extenders with new antioxidant substances can optimize the properties of post-thawed semen. The study aimed to investigate the addition effect of medium-molecular-weight carboxymethylchitosan (CQm) derivates to freezing diluent of stallion sperm after freezinf/thawing. Twice a week, five ejaculates of four stallions were obtained, totalizing 20 ejaculates. Semen was diluted in commercial freezing extender (Botucrio) supplemented with CQm: control (0), 0.75, 1.5, and 3 mg/mL. Samples were ...
Freezability and Fertility Rates of Stallion Semen Supplemented With Trehalose in Lactose Extender.
Journal of equine veterinary science    March 21, 2023   Volume 126 104293 doi: 10.1016/j.jevs.2023.104293
Jhamb D, Talluri TR, Sharma S, Juneja R, Nirwan SS, Yadav D, Pargi KK, Tanwar A, Kumar P, Kumar R, Mehta SC, Parashar M, Gaur M.Cryopreservation of stallion semen is often associated with poor post-thaw sperm quality. One of the reason for this diminished quality is osmotic stress that spermatozoa experiences during freezing and thawing process. The aim of the present study was to evaluate the cryoprotective effect of trehalose on stallion sperm quality and field fertility rates subjected to cooling and freeze-thawing process. Semen samples were collected from six Marwari breed stallions, divided into three different treatments in a final concentration of 150 × 10 sperm/mL by using Lactose based extender containing ...
Erratum: Single-cell gene expression analysis of cryopreserved equine bronchoalveolar cells.
Frontiers in immunology    March 13, 2023   Volume 14 1178189 doi: 10.3389/fimmu.2023.1178189
[This corrects the article DOI: 10.3389/fimmu.2022.929922.].
Vitrifying expanded equine embryos collapsed by blastocoel aspiration is less damaging than slow-freezing.
Theriogenology    March 2, 2023   Volume 202 28-35 doi: 10.1016/j.theriogenology.2023.02.028
Umair M, Beitsma M, de Ruijter-Villani M, Deelen C, Herrera C, Stout TAE, Claes A.The cryotolerance of equine blastocysts larger than 300 μm can be improved by aspirating blastocoele fluid prior to vitrification; however, it is not known whether blastocoele aspiration also enables successful slow-freezing. The aim of this study was therefore to determine whether slow-freezing of expanded equine embryos following blastocoele collapse was more or less damaging than vitrification. Grade 1 blastocysts recovered on day 7 or 8 after ovulation were measured (>300-550 μm, n = 14 and > 550 μm, n = 19) and blastocoele fluid was aspirated prior to slow-freezing in 10...
Egg yolk plasma enriched with β-carotene through the diet of laying hens and adding it to the extender improves the quality of frozen semen in Arabic stallions.
Reproduction in domestic animals = Zuchthygiene    February 27, 2023   Volume 58, Issue 5 630-636 doi: 10.1111/rda.14334
Hatami M, Qasemi-Panahi B, Daghigh Kia H, Moghaddam G, Janmohammadi H.Equine semen cryopreservation is one of the major procedures for the genetic conservation of rare and endangered genotypes. The current study was conducted to evaluate the effect of egg yolk plasma (EYP) enriched with β-carotene as an antioxidant supplement on INRA-96 extender regarding freezing Arabic stallion sperm. For this purpose, β-carotene various concentrations were utilized as a supplementary ingredient in formulating the diets of laying hens. Birds were randomly divided into four groups, fed with 0 (control), 500, 1000 and 2000 mg/kg in a supplemented diet with β-carotene. Subse...
Seasonality does not influence cortisol or testosterone production, or seminal quality of stallions located at low latitudes.
Animal reproduction science    February 23, 2023   Volume 250 107202 doi: 10.1016/j.anireprosci.2023.107202
Freitas ML, Viana JHM, Dode MAN, Maggiotto SR, Pivato I, Braga TRC, Lim AIPG, de Oliveira RA.The effects of seasonality on the reproduction of stallions vary based on the latitude. Although previous studies have shown the influence of seasonality in raw semen quality in south-eastern Brazil, data regarding the influence of seasonality in cooled and frozen stored semen in Brazil is limited. Therefore, in this study, we have analysed if seasonality influences the hormone production (i.e., cortisol and testosterone), spermatogenesis, and quality of fresh, cooled, and frozen semen of stallions in central Brazil, and established the season most suitable for semen cryopreservation in a lati...
Optimization of the Equine-Sperm Freeze Test in Purebred Spanish Horses by Incorporating Colloidal Centrifugation.
Animals : an open access journal from MDPI    January 22, 2023   Volume 13, Issue 3 382 doi: 10.3390/ani13030382
Gutiu00e9rrez-Cepeda L, Crespo F, Blazquez JC, Serres C.The Purebred Spanish Horse, according to our clinical experience, is characterized by having a high number of stallions that do not meet the international commercial recommendations for equine-sperm cryopreservation. This means that artificial insemination with frozen semen from these stallions is less widespread than in other breeds. In this study, we investigated if the incorporation of single-layer colloidal centrifugation prior to cryopreservation in clinical conditions could increase the number of ejaculates of Purebred Spanish stallions suitable for this processing, observing the influen...
Culture of equine intestinal epithelial stem cells after delayed tissue storage for future applications.
BMC veterinary research    December 23, 2022   Volume 18, Issue 1 445 doi: 10.1186/s12917-022-03552-6
Stewart AS, Schaaf CR, Veerasammy B, Freund JM, Gonzalez LM.Equine intestinal epithelial stem cells (ISCs) serve as potential targets to treat horses with severe intestinal injury. The ability to isolate and store ISCs from intestinal biopsies creates an opportunity for both in vitro experiments to study ISC dynamics in a variety of intestinal diseases, and, in the future, utilize these cells as a possible therapy. If biopsies could be successfully stored prior to processing for ISCs, this would increase the availability of sample repositories for future experimental and therapeutic use. However, delayed culture of equine ISCs following prolonged sampl...
Selection of frozen-thawed stallion semen by microfluidic technology.
Reproduction in domestic animals = Zuchthygiene    December 20, 2022   Volume 58, Issue 3 443-449 doi: 10.1111/rda.14305
Vigolo V, Gautier C, Falomo ME, Aurich C.The use of microfluidic technology is increasing in artificial reproduction technologies: With a small amount of semen, it allows for the selection of sperm with the best characteristics of kinetics, morphology and chromatin integrity. The ZyMot Multi (850 μl) is the most popular device of ZyMot Fertility Inc. To date, it was proven to be a valid instrument for sperm selection for in vitro fertilization and intracytoplasmic sperm injection in men. The aim of this study was to test the efficacy of the ZyMot Multi (850 μl) for stallion semen. Frozen-thawed semen from 15 stallions that were...
Cryopreserved equine amniotic membrane and its use in cutaneous wounds of horses.
Brazilian journal of veterinary medicine    December 14, 2022   Volume 44 e003122 doi: 10.29374/2527-2179.bjvm003122
Rosa MVD, Rosa M, Botteon PTL.This study aimed to evaluate the use of equine amniotic membrane (EAM), frozen indirectly using liquid nitrogen and stored between -10° and -24°C, in the treatment of equine skin lesions. Six healthy female horses, aged 3-10 years, were included in this study. EAM was collected from previously evaluated healthy parturient mares. Wounds were surgically created at the distal ends of the forelimbs. One limb was chosen for treatment, and the contralateral limb was chosen as the control. Pain sensitivity, presence of granulation tissue, secretions, and bleeding after debridement during cleaning w...
Phosphoproteomics for the identification of new mechanisms of cryodamage: the role of SPATA18 in the control of stallion sperm function†.
Biology of reproduction    December 6, 2022   Volume 108, Issue 2 324-337 doi: 10.1093/biolre/ioac211
Gaitskell-Phillips G, Martu00edn-Cano FE, da Silva-u00c1lvarez E, Tapia JA, Silva A, Gil MC, Ortega-Ferrusola C, Peu00f1a FJ.Although recent research has addressed the impact of cryopreservation on the stallion sperm proteome, studies addressing the stallion sperm phosphoproteome are lacking. In the present study, the data set of proteomes of fresh and cryopreserved spermatozoa were reanalyzed, showing that cryopreservation caused significant changes in the phosphoproteome. The phosphoproteins reduced most significantly by cryopreservation were Ca2+binding tyrosine phosphorylation regulated, protein kinase cAMP-activated catalytic subunit beta (CABYR), mitochondria eating protein (SPATA18), A kinase anchoring protei...
ProAKAP4 Concentration Is Related to Sperm Motility and Motile Sperm Subpopulations in Frozen-Thawed Horse Semen.
Animals : an open access journal from MDPI    December 4, 2022   Volume 12, Issue 23 3417 doi: 10.3390/ani12233417
Dordas-Perpinyu00e0 M, Yanez-Ortiz I, Sergeant N, Mevel V, Bruyas JF, Catalu00e1n J, Delehedde M, Briand-Amirat L, Miru00f3 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...
Freeze-dried Platelet-rich Plasma and Stem Cell-conditioned Medium for Therapeutic Use in Horses.
Journal of equine veterinary science    December 2, 2022   Volume 121 104189 doi: 10.1016/j.jevs.2022.104189
Freitas NPP, Silva BDP, Bezerra MRL, Pescini LYG, Olinda RG, Salgueiro CCM, Nunes JF, Martins JAM, Neto SG, Martins LT.This study investigated platelet-rich plasma (PRP) and adipose stem cell-conditioned medium (ASC-CM) use as a strategy to accelerate tissue healing. Platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) were quantified in fresh and freeze-dried PRP and ASC-CM, and a stability test was performed in the freeze-dried samples (90 and 180 days of storage). A cell proliferation test was performed using equine mesenchymal stem cell culture in reconstituted PRP gel mesh after freeze-drying. In vivo PRP, ASC-CM applications, or their association were performed in induced w...
An Investigation of Equine Sperm Quality Following Cryopreservation at Low Sperm Concentration and Repeated Freeze-Thawing.
Journal of equine veterinary science    December 1, 2022   Volume 120 104167 doi: 10.1016/j.jevs.2022.104167
Morse-Wolfe B, Bleach E, Kershaw C.Stallion spermatozoa are typically cryopreserved at 200 to 300 million sperm/ml; however recent advances such as intracytoplasmic sperm injection (ICSI) requires only one spermatozoon, wasting many, after thawing a whole straw. Cryopreserving at concentrations less than the current standard or refreezing thawed spermatozoa could maximize the use of genetically valuable animals and reduce waste. This investigation aimed to identify if lowering the sperm concentration for cryopreservation affected post-thaw quality after one and two freeze-thaw cycles. Nine ejaculates were collected from three f...
Effects of egg yolk level, penetrating cryoprotectant, and pre-freeze cooling rate, on the post-thaw quality of stallion sperm.
Animal reproduction science    December 1, 2022   Volume 248 107162 doi: 10.1016/j.anireprosci.2022.107162
Hernu00e1ndez-Avilu00e9s C, Ramu00edrez-Agu00e1mez L, Varner DD, Love CC.The current study determined the effect of the egg-yolk (phospholipid source) level (egg yolk [20% EY] vs. skim-milk + egg yolk [SM + 2% EY]), cryoprotectant (glycerol [Gly] vs. glycerol + methylformamide [Gly + MF]), and pre-freeze cooling rate (-0.1 vs. -1 vs. -5 °C/min) on post-thaw stallion sperm quality. In Experiment 1, ejaculates (n = 27) from 9 stallions (3 ejaculates each) with varied sperm quality (High, Average, or Low) were frozen in EY-Gly, SMEY-Gly, EY-Gly + MF, or SMEY-Gly + MF extenders. Sperm in each group were cooled from 22° to 5°C using either -0.1 °C/min or -1 �...
Effect of different concentrations of Trolox® in association with docosahexaenoic acid on equine semen freezing.
Animal reproduction    November 28, 2022   Volume 19, Issue 4 e20220010 doi: 10.1590/1984-3143-AR2022-0010
Aguiar CS, Barros CHSC, Machado WM, Allaman IB, Leite AO, Barbosa LP, Snoeck PPDN.The aim of this study was to evaluate the association of different concentrations of Trolox and the addition of a fixed concentration of DHA in the freezing of semen of Mangalarga Marchador stallions. To that end, 16 ejaculates were frozen in the following extenders: E1) BotuCrio (BC; Control); E2) BC + 50 ngml DHA + 30 µM Trolox (BCDHA30T); E3) BC + 50 ngml DHA + 40 µM Trolox (BCDHA40T); E4) BC + 50 ngml DHA + 50 µM Trolox (BCDHA50T). All the tested extenders were similar in preserving different kinematic parameters, cell functional integrity, compacted DNA, and high and intermediate mitoc...
Penicillin and amikacin mixture has bactericidal activity equivalent to gentamicin, tylosin, lincomycin and spectinomycin mixture in equine frozen semen.
Reproduction in domestic animals = Zuchthygiene    November 25, 2022   Volume 58, Issue 2 349-357 doi: 10.1111/rda.14294
Brito LFC, Loomis PR, Klohonatz KM, Althouse GC.Neat stallion semen can contain a variety of microorganisms, some of which may impair sperm quality and/or cause infection of the mares' reproductive tract. For this reason, antibiotics are commonly added to semen extenders. A combination of gentamicin, tylosin, lincomycin and spectinomycin (GTLS) has been recommended for use, but there are no reports on the use of this mixture in equine semen extender. Penicillin and amikacin (PA) are safe for preserving sperm quality while effectively controlling bacterial growth in equine cooled stored semen, but data on frozen semen are scarce. Therefore, ...
Action of swim-up and caffeine on equine frozen sperm.
Animal reproduction    November 21, 2022   Volume 19, Issue 4 e20220056 doi: 10.1590/1984-3143-AR2022-0056
Alves NC, Diniz SA, Viegas RN, Arigoni AL, Freitas MM, Lana u00c2Q, Lagares MA.Cryopreservation of equine semen is crucial to semen commercialization. However, it reduces sperm motility and longevity. Thus, sperm selection methods and addition of motility-activating substances to sperm, such as caffeine, may improve sperm quality of equine frozen semen. The objective of the current work was to evaluate the effects of caffeine on recovery and quality parameters of frozen-thawed sperm subjected to swim-up selection to be used in intracytoplasmic sperm injection (ICSI) in assisted reproductive techniques. Stallion semen were frozen and after thawing different caffeine conce...
OXIDATIVE STRESS AND REPRODUCTIVE FUNCTION: Oxidative stress and the long-term storage of horse spermatozoa.
Reproduction (Cambridge, England)    November 18, 2022   Volume 164, Issue 6 F135-F144 doi: 10.1530/REP-22-0264
Peu00f1a 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...
Sperm factors associated with the production of equine blastocysts by intracytoplasmic sperm injection (ICSI) using frozen/thawed semen.
Theriogenology    October 17, 2022   Volume 195 85-92 doi: 10.1016/j.theriogenology.2022.10.014
Ramu00edrez-Agu00e1mez L, Hernu00e1ndez-Avilu00e9s C, Varner DD, Love CC.Intracytoplasmic Sperm Injection (ICSI) using frozen/thawed sperm is a common procedure to obtain embryos from fertile or subfertile mares and stallions. Stallion-associated factors that impact the efficiency of ICSI have been studied less than those associated with the mare. Three experiments were conducted: Experiment 1: the effect of freezing extender composition and cryoprotectant; Experiment 2: the effect of sperm exposure to seminal plasma prior to freezing (ejaculated vs. epididymal sperm; two-freeze/thaw cycles each); and Experiment 3: the effect of sperm morphologic feature used for f...
Liquid storage of stallion spermatozoa – Past, present and future.
Animal reproduction science    October 6, 2022   Volume 247 107088 doi: 10.1016/j.anireprosci.2022.107088
Clulow J, Gibb Z.The ability to store stallion spermatozoa between the events of semen collection and insemination has facilitated improved rates of gain in selective breeding programs by enabling the transport of spermatozoa. While cryopreservation is the only viable means of storing spermatozoa for long intervals, the higher costs and reduced fertility of cryopreserved spermatozoa have led to most breeders opting to use liquid stored spermatozoa. Stallion spermatozoa is commonly cooled during liquid storage (approximately 4-5 °C), and there has been an enormous body of research dedicated to development of ...
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