Fertility in horses encompasses the physiological processes and factors influencing reproductive success in equine species. It involves the study of reproductive anatomy, endocrinology, and behavior, as well as the management practices that affect breeding outcomes. Key aspects include the estrous cycle, conception rates, and factors impacting stallion and mare fertility. Reproductive technologies such as artificial insemination, embryo transfer, and hormonal therapies are also explored to enhance breeding efficiency. This page compiles peer-reviewed research studies and scholarly articles that examine the biological mechanisms, management strategies, and technological advancements related to equine fertility.
Chowdhary BP, Paria N, Raudsepp T.Following the recent development of high-resolution gene maps and generation of several basic tools and resources to use them in analyzing traits that are economically important to horse owners, genome analysis in horses is witnessing a shift towards developing an ability to analyze complex traits. The likelihood of this happening in the very near future is great, mainly because of the recent availability of the whole genome sequence in the horse. The latter has triggered the development of novel tools like SNP-chip and expression arrays that will permit rapid genome-wide analysis. While these...
Kareskoski M, Katila T.Seminal plasma is a mixture of secretions produced in the testes, epididymides and accessory sex glands, and ejaculated as several consecutive fluid fractions. The composition of seminal plasma and the effects on sperm longevity vary between fractions and individual stallions. This review focuses on the sequence of ejaculation, constituents of seminal plasma and their potential use as fertility markers as well as the influence of seminal plasma on spermatozoa during storage.
Aurich C.The majority of horse registries approve the use of artificial insemination, and horse breeding has widely taken benefit from the use of cooled-stored semen. New insights into cooled-semen technology open possibilities to reduce problems such as impaired semen quality after cooled-storage in individual stallions. The stallion itself has major impacts on quality and fertility of cooled-stored semen. Dietary supplementation of antioxidants and polyunsaturated fatty acids improves semen quality in a variety of species, but only few studies on this topic exist in the horse. Proper semen collection...
Sostaric E, Aalberts M, Gadella BM, Stout TA.The epididymis is a long, tightly coiled tube within the lumen of which sperm matures. Sperm maturation involves morphological and biochemical changes in the sperm plasma membrane in response to epididymal secretions and their various proteins. Some of these proteins become outer membrane components while others become integral membrane proteins; transfer of some proteins to the sperm plasma membrane may be mediated by epididymosomes. Nevertheless, the molecular pathways by which spermatozoa acquire fertilizing capacity during their transit through the epididymis remain ambiguous. In a recent ...
Brum AM, Sabeur K, Ball BA.The objective was to evaluate apoptotic markers in ejaculated equine spermatozoa after separation by density-gradient centrifugation and after cryopreservation. Subpopulations of percoll-separated equine spermatozoa differed (P<0.05) in the percentage of live, caspase-activated spermatozoa (2.9+/-0.7% vs 14.2+/-6.4%; mean+/-S.E.M.), low mitochondrial membrane potential (MMP; 6.8+/-1.1 vs 23.8+/-3.7), altered plasma membrane permeability (1.3+/-0.2 vs 3.0+/-0.5), DNA fragmentation (2.0+/-1.3 vs 14.3+/-3.6), total motility (81.8+/-3.3 vs 35.1+/-5.4), and progressive motility (66.3+/-4.3 vs 24...
López-Bayghen C, Zozaya H, Ocampo L, Brumbaugh GW, Sumano H.The efficacy of melengestrol acetate (MGA) to shorten the vernal transition of mares by synchronising and accelerating the first ovulation of the year after 60 days of phototherapy was determined by ultrasonographic monitoring. Sixteen mares in late transition were fed two doses of MGA (150 mg/mare/day and 100 mg/mare/day, respectively) for 10 days. A luteolytic dose of prostaglandin was administered to each mare one day after the end of MGA treatment. The presence and duration of oestrus, follicular growth, uterine oedema and presence of ovulation were monitored by ultrasonography and the cer...
Ginther OJ, Beg MA, Neves AP, Mattos RC, Petrucci BP, Gastal MO, Gastal EL.Plasma concentrations of FSH, LH, oestradiol and progesterone were studied daily during 12 interovulatory intervals and 21 periovulatory periods in nine Miniature ponies. The peak of the FSH surge that was temporally associated with emergence of the future ovulatory follicle occurred when the follicle was approximately 9 mm, compared with a reported diameter of 13 mm in larger breeds. The ovulatory LH surge involved a slow increase between Days 13 and 18 (ovulation=Day 0; 0.6+/-0.1 ng day(-1)), a minimal increase or a plateau on Days 18 to 21 (0.04+/-0.1 ng day(-1)), and a rapid increase after...
Chen J, Weng Q, Chao J, Hu D, Taya K.In China, the first Przewalski's horse (Equus przewalskii) group was released in Kalamaili Ungulate Protected Area in Xinjiang, in August 2001. The objective of this study was to investigate reproduction and development of released Przewalski's horses in Xinjiang, China from 2002 to 2006. Twenty-four descendants were naturally born, average reproduction rate was 38.7%, and average survival rate of foals was 69.1% in this interim. Frequent alternation of the leading stallion and infertility in female horses due to environmental factors were main causes for the low reproduction rate. The infant ...
Cavalcanti MC, Rizgalla M, Geyer J, Failing K, Litzke LF, Bergmann M.In eukaryotic cells, the major protein constituents of the chromatin are histones, which can be divided into five classes, identified as H1, H2A, H2B, H3 and H4. During normal spermatogenesis, a testis-specific H1t is expressed in primary spermatocytes and believed to facilitate histone to protamine exchanges during spermiogenesis. In equine testes we detected the H1 protein at 22kDa by western blot analysis while H1t was detected at 29kDa. H1 protein was found to be expressed in all germ cells up to elongating spermatids (Sc) at stage IV. In peripubertal animals, there was a prolonged express...
Vidament M, Vincent P, Martin FX, Magistrini M, Blesbois E.A suitable method for the cryopreservation of donkey semen would be very valuable for the ex situ management of genetic diversity in this species. This report uses a variety of observation and trials to evaluate the effect of cryoprotectants in per-cycle pregnancy rates (PC) in equids females (jennies (donkey) and mares (horse)). This was explored by (1) comparing the results of insemination of jennies and mares with cooled or frozen donkey semen, (2) examining the possible toxic effect of the cryoprotectant (CPA) glycerol in these two species and (3) studying alternative solutions. Donkey and...
Ginther OJ, Gastal EL, Gastal MO, Beg MA.Reported data were reviewed and reexamined to evaluate the concept that most of the follicular fluid enters the peritoneal cavity at ovulation in mares and transiently alters the circulating concentrations of LH, FSH, estradiol, and inhibin. A transrectal ultrasonographic study supported the hypothesis that the large volume (40-50 ml) of evacuated follicular fluid passes through the infundibular fimbriae into the peritoneal cavity. A spike in circulating inhibin and a decrease in the rate of reduction in circulatory estradiol occurs at ovulation. Simultaneously, a disruption occurs in the incr...
Deichsel K, Palm F, Koblischke P, Budik S, Aurich C.Lipid peroxidation contributes to the damage of the sperm plasma membrane. In different species, dietary supplementation with antioxidants has been shown to improve semen quality. Therefore, we tested effects of dietary supplementation with antioxidants and l-carnitin on semen quality in Shetland pony stallions (n=6). Semen was collected twice a week over a time period of 16 weeks. From weeks 5 to 12, a special diet for stallions containing a variety of antioxidants (STALLION, Pavo Pferdenahrung GmbH, Goch, Germany; tocopherol 300 mg/day; ascorbic acid 300 mg/day; l-carnitin 4000 mg/day; folic...
Maischberger E, Irwin J, Carrington S, Duggan V.The deposition of semen, bacteria and debris in the uterus of the mare after breeding normally induces a self-limiting endometritis. The resultant fluid and inflammatory products are cleared by 48 hours post cover. Mares that are susceptible to persistent post-breeding endometritis (PPBEM) have impaired uterine defence and clearance mechanisms, making them unable to resolve this inflammation within the normal time. This persists beyond 48 hours post-breeding and causes persistent fluid accumulation within the uterus. Mares with PPBEM have an increased rate of embryonic loss and a lower overall...
Crowe CA, Ravenhill PJ, Hepburn RJ, Shepherd CH.Historically, artificial insemination (AI) using frozen semen has been perceived to have poorer success rates and be more labour intensive than using chilled semen. A retrospective study was therefore conducted to compare the conception rate achieved by AI between chilled and frozen semen, using fixed time insemination protocols over 2 breeding seasons. Objective: Artificial insemination using chilled semen produces a higher conception rate than that achieved with frozen semen. Methods: Mares (n = 251) were inseminated with either chilled (n = 112) or frozen (n = 139) semen in the 2006 and 200...
Cuervo-Arango J, Newcombe JR.Follicular diameter is used as a guiding tool to predict ovulation in the mare. However, the great range in preovulatory follicular diameter makes prediction of optimal breeding time based on follicular diameter unreliable. Uterine edema pattern is also useful to determine the best time to breed, since intensity of edema tends to dissipate as ovulation approaches, however, not every mare follows this pattern. The aims of this study were to assess the repeatability of preovulatory follicular diameter and uterine edema pattern in two consecutive spontaneous cycles and to determine how induction ...
McPartlin LA, Littell J, Mark E, Nelson JL, Travis AJ, Bedford-Guaus SJ.Efficient in vitro capacitation of stallion sperm has not yet been achieved, as suggested by low sperm penetration rates reported in in vitro fertilization (IVF) studies. Our objectives were to evaluate defined incubation conditions that would support changes consistent with capacitation in stallion sperm. Protein tyrosine phosphorylation events and the ability of sperm to undergo acrosomal exocytosis under various incubation conditions were used as end points for capacitation. Sperm incubated 4-6h in modified Whitten's (MW) with the addition of 25 mM NaHCO3 and 7 mg/mL BSA (capacitating mediu...
Ginther OJ, Gastal EL, Rodrigues BL, Gastal MO, Beg MA.Relationships between double ovulations and plasma hormone concentrations were compared between 18 single ovulating and 6 double ovulating mares. The study began when the first follicle reached >or=30 mm, and ultrasound scanning and blood sampling were done every 12h to Day 3 (ovulation=Day 0). Data were analyzed for 2.5 d after the largest follicle was >or=30 mm and after Day -2.5 to encompass the mean 5-d interval between a >or=30 mm follicle and Day 0. During the 2.5 d after >or=30 mm, the increasing diameter of the largest follicle was less pronounced and plasma FSH concentrati...
Mortensen CJ, Choi YH, Hinrichs K, Ing NH, Kraemer DC, Vogelsang SG, Vogelsang MM.The effect of exercise on mare reproductive efficiency was evaluated by comparing rates of embryo recovery from mares assigned to either an exercise regimen or a non-exercise (control) regimen. Exercised mares were worked daily for 30 min under average ambient conditions of >30 degrees C and >50% humidity. Mares were inseminated during estrus and subjected to uterine flush for embryo recovery on d 7 after ovulation for two consecutive cycles. After this, mares were allocated to the opposite group and allowed an estrous cycle without reproductive manipulation; then insemination and uterin...
Morrell JM, Johannisson A, Dalin AM, Hammar L, Sandebert T, Rodriguez-Martinez H.Artificial insemination is not as widely used in horses as in other domestic species, such as dairy cattle and pigs, partly because of the wide variation in sperm quality between stallion ejaculates and partly due to decreased fertility following the use of cooled transported spermatozoa. Furthermore, predictive tests for sperm fertilising ability are lacking. The objective of the present study was to assess sperm morphology and chromatin integrity in ejaculates obtained from 11 warmblood breeding stallions in Sweden, and to evaluate the relationship of these parameters to pregnancy rates to i...
Ginther OJ, Jacob JC, Gastal MO, Gastal EL, Beg MA.The characteristics of ovulatory follicular waves were studied for spontaneous waves and waves induced during the next estrous cycle by ovarian follicle ablations and administration of PGF2alpha 10 days after ovulation in 21 mares. In the induced group, both the days of the FSH surge and day of deviation were more synchronized, LH concentrations were greater before and after deviation, estradiol concentrations were greater after deviation, and the ovulatory follicle grew at a faster rate (3.4+/-0.2 compared with 2.7+/-0.1 mm/day). The frequency of two dominant follicles/wave was not different ...
Lefranc A-, Allen WR.The diffuse noninvasive epitheliochorial equine placenta develops an intimate and complex interdigitation with the maternal endometrium throughout gestation to maximise surface contact and, consequently, optimise nutritional and gaseous maternofetal exchanges. A significant reduction occurs in the surface density of microcotyledons on the placentae of Welsh Pony vs. Thoroughbred mares that may relate to a difference in either the number or density of endometrial glands between these breeds. Objective: To examine this hypothesis and to determine the influence of the oestrous cycle upon the deve...
Nimmo MR, Slone DE, Hughes FE, Lynch TM, Clark CK.To report fertility (foals conceived, live foal births) of mares after partial fetotomy to resolve dystocia and complications associated with fetotomy. Methods: Retrospective study. Methods: Horses (n=20). Methods: Medical records (2001-2006) of mares that had partial fetotomy (1-3 cuts) for dystocia were reviewed. Complications and subsequent fertility were obtained by interview and live foal data were recorded by the Jockey Club. Postfetotomy conception and live foals produced over 21 breeding seasons (defined as years each mare was bred regardless of conception) were recorded. Results: Twen...
Leeb T.The growing knowledge on physiology, cell biology and biochemistry of the reproductive organs has provided many insights into molecular mechanisms that are required for successful reproduction. Research directed at the investigation of reproduction physiology in domestic animals was hampered in the past by a lack of species-specific genomic information. The genome sequences of dog, cattle and horse have become publicly available in 2005, 2006 and 2007 respectively. Although the gene content of mammalian genomes is generally very similar, genes involved in reproduction tend to be less conserved...
Price S, Aurich J, Davies-Morel M, Aurich C.This study was undertaken to investigate the effects of storage of stallion semen in a defined milk protein extender at 5 and 15 degrees C under either anaerobic or aerobic conditions, with or without addition of the antibiotic gentamicin. Semen samples were collected from eight fertile stallions and stored for 96 h (day 0-4) and assessed daily for motility, velocity and membrane integrity (viability) using a CASA system. Samples for bacteriology assessment were taken on day 2 of storage. No significant (p > 0.05) differences in motility, velocity or viability were observed between treatmen...
Loomis PR, Graham JK.One of the challenges for those attempting to cryopreserve stallion spermatozoa is dealing with the stallion to stallion variability in the cryosurvival of their semen. In the dairy industry, each bull stud, essentially utilizes a single cryopreservation technique, and bulls that produce sperm that do not cryopreserve well using that technique are replaced by other bulls. However, replacing stallions is unlikely to prove acceptable to the equine industry, where specific genotypes are desired. Instead, to increase the number of stallions that can be effectively utilized for cryopreserved semen ...
Ginther OJ, Gastal EL, Gastal MO, Beg MA.The effect of an injection of a supraphysiologic dose of rhIGF1 into the second-largest ovarian follicle (F2) at the expected beginning of deviation (F1, > or =20 mm; Day 0) on development of dominance by F2 was studied in mares (n=16; controls, n=8). F1 became dominant (> or =28 mm) in 8 of 8 and 15 of 16 follicles in the controls and treated groups, respectively. The incidence of dominance (P<0.001) and ovulation (P or =20mm after the expected beginning of deviation resulted in dominance by 8 of 12 follicles treated with rhIGF1 on Days 1-3 (n=8 mares). Results demonstrated that the ...
Saragusty J, Gacitua H, Pettit MT, Arav A.Despite its potential impact on the horse industry, sperm cryopreservation is not an established technology throughout the industry, for a number of reasons that include a reduction in pregnancy rate and increased cost per pregnancy. We have evaluated a novel directional freezing technique, based on a multi-thermal gradient (MTG), by comparing it with the conventional, controlled-rate cryopreservation method (CRCM). Ninety-seven ejaculates with > or =50% motility, collected from 31 stallions were each divided into two parts and subsequently frozen by either MTG or CRCM. Frozen samples were ...
Carnevale EM.Reproductive aging and assisted reproduction are becoming progressively more relevant in human medicine. Research with human subjects is limited in many aspects, and consequently animal models may have considerable utility. Such models have provided insight into follicular function, oocyte maturation, and reproductive aging. However, models are often selected based on factors other than physiological or functional similarities. Although the mare has received limited attention as a model for reproduction in women, comparisons between these species indicate that the mare has many attributes of a...
Davies Morel MC, Newcombe JR.Despite the widespread use of hCG to advance ovulation in the mare there is little information on efficacy of dose rates and any contraindications of its use. This study aims to investigate the effect of dose of hCG on ovulation within 48h and the effect of hCG on: ovulation, multiple ovulation (MO), pregnancy, multiple pregnancy (MP) rates and synchrony of MO; additionally whether any seasonal effect is evident. Sequential ultrasonic scanning was used to monitor the occurrence of ovulation, within 48h of treatment, in 1291 Thoroughbred mares treated with either 750iu hCG or 1500iu hCG s.c. Ov...
López-Fernández C, Crespo F, Arroyo F, Fernández JL, Arana P, Johnston SD, Gosálvez J.The mixed success of equine artificial insemination programs using chilled and frozen-thawed semen is most likely associated with the variable response of the sperm cell to the preservation process and the fact that stallions are not selected on the basis of reproductive performance. We propose that the traditional indicators of sperm viability do not fully account for male factor infertility in the stallion and that knowledge of sperm DNA damage in the original semen sample and during semen processing may provide a more informed explanation of an individual stallion's reproductive potential. ...
Morris LH, Maclellan LJ.The increased commercialisation of intracytoplasmic sperm injection (ICSI) in horses creates more opportunities to incorporate advanced reproductive technologies, such as sex-sorted, refrozen and lyophilised spermatozoa, into a breeding program. This paper reviews the status of these semen-handling technologies in light of their use in equine ICSI programs. Pregnancies have been achieved from each of these advanced technologies when combined with ICSI in horses, but refinements in the semen-handling processes underpinning these technologies are currently being explored to produce more reliable...
Becker SE, Johnson AL.Studies were conducted to compare continuous vs pulsatile i.v. infusion of GnRH on serum gonadotropin concentrations and ovulation in seasonally anestrous mares and in cycling mares. Anestrous mares (Exp. 1) received no treatment (control; n = 3), 2, or 20 micrograms of GnRH/h continuous infusion (CI) (n = 4 and n = 6, respectively), or 20 micrograms of GnRH/h pulsatile infusion (PI) (n = 5). After initiation of GnRH infusion, serum LH levels increased earlier, and to a greater extent, in the PI group than in other groups (P less than .05). In contrast, serum FSH concentrations did not differ ...
Data in briefJune 20, 2020
Volume 31 105887 doi: 10.1016/j.dib.2020.105887
Martín-Cano FE, Gaitskell-Phillips G, Ortiz-Rodríguez JM, Silva A, Gil C, Ortega-Ferrusola C, Peña FJ.This paper provides the dataset of proteins of stallion ejaculates before and after cryopreservation. The data report the analysis and identification of stallion sperm proteins obtained from the same ejaculates and split in two subsamples. The first aliquot consisted on fresh spermatozoa and the second aliquot was frozen and thawed spermatozoa. Samples were analyzed using a UHPLC/MS/MS system consisting of an Agilent 1290 infinity series UHPLC coupled to an Agilent 6550 Q-TOF mass spectrometer (Agilent Technologies, Santa Clara, CA, USA). We provide a data set of 2226 different proteins, with ...
Lemazurier E, Séralini GE.Our previous work showed that stallion testis produces high amounts of estrogens which are subsequently found in the ejaculate. These estrogens are mainly synthesized by testicular aromatase, and the major estrogen produced is estrone sulfate (E1S). The objective of this study was to investigate the potential role of E1S as a source of estrogens in the male and female horse reproductive tracts by determining whether both estrone sulfatase (Sulf) and 17beta-hydroxysteroid dehydrogenase type I (17beta-HSD1) activities were present in equine testes, epididymis and uterus. We assessed E1S bioconve...
Gastal EL, Gastal MO, Ginther OJ.Ultrasonically detected changes in the equine preovulatory follicle were characterized for the 3 d preceding ovulation early (n = 47) and late (n = 14) in the ovulatory season. Values for the following follicle end points increased progressively over the 3 d: diameter, incidence of nonspherical shape, echogenicity of the apparent granulosa layer, and prominence of an anechoic layer beneath the granulosa. The latter 2 echotexture end points were scored from 1 to 3 (minimal to maximal). Follicle diameter and the 2 echotexture characteristics were more prominent early than late in the ovulatory s...
Squires EL, McKinnon AO.Because the reproductive performance of mares is lower than that of any other domesticated species, hormone therapy is important in ensuring fertility and proper management of pregnancy. Current techniques of hormone therapy are discussed.
Papkoff H.The objectives of this paper are to review the chemical and biological properties of equine chorionic gonadotropin (eCG, PMSG) isolated from the serum. Comparisons are made with eCG isolated from endometrial cups, trophoblast cell culture medium, and low titer serum. The results show that eCG can vary, depending on the source, in both chemical and biological (LH and FSH activity) properties.
Saadi A, Azizi S, Farshid AA, Yousefi A.This report describes surgical management and breeding implications of a case of penile sarcoid associated with penis laceration in a 4-year-old Kurdish stallion. A large fleshy mass on the distal end of the penis that resulted in urethral meatus deviation and dysuria was detected in a physical examination. No evidence of local extent or metastasis was detected. Under general anaesthesia, the involved distal portion of the penis was removed through partial phallectomy. Histopathological examination of the mass confirmed a fibroblastic sarcoid. Partial phallectomy was successful for management ...
Pastorello M, Gastal MO, Godoi DB, Gastal EL.Among female livestock, the mare has the shortest interval from parturition to first ovulation. Due to the scarcity of research on postpartum mares, little progress has been made on the characterization of the resumption of ovarian cyclicity after parturition. This study compared follicular and gonadotropin dynamics during follicle emergence and deviation in postpartum lactating (PP Lactating) versus non-postpartum cycling (N-PP Cycling) mares. On the day of parturition, every PP Lactating mare was paired with a N-PP Cycling mare. Comparisons were made by considering the partum-ovulation inter...
Guasti PN, Monteiro GA, Maziero RR, Carmo MT, Dell'Aqua JA, Crespilho AM, Rifai EA, Papa FO.The aims of this study were to determinate whether pentoxifylline (PTX) increases the motion parameters of fresh and frozen-thawed equine epididymal spermatozoa, to evaluate the tyrosine phosphorylation of frozen-thawed epididymal sperm in the presence of PTX and to determine whether the PTX-treatment of stallion epididymal sperm prior to freezing improves the fertility response of mares to a reduced number of spermatozoa per insemination dose. Fifty epididymis were flushed with a skim milk based extender with or without PTX. The pre-treatment with PTX enhanced the sperm motility after being h...
Carnevale EM, Coutinho da Silva MA, Maclellan LJ, Seidel GE, Squires EL.Parentage identification was used to test the developmental competence of oocytes cultured under different conditions and fertilized in vivo after oocyte transfer. Oocytes were collected transvaginally from follicles of estrous mares approximately 22 h after administration of human chorionic gonadotropin. Oocytes were cultured for approximately 16 h in one of three media, with or without addition of hormones and growth factors. Groups of three or four oocytes, cultured in different media, were transferred into the oviduct contralateral to a recipient's own ovulation. Recipients were inseminate...
Davies Morel MC, Newcombe JR.Despite the widespread use of hCG to advance ovulation in the mare there is little information on efficacy of dose rates and any contraindications of its use. This study aims to investigate the effect of dose of hCG on ovulation within 48h and the effect of hCG on: ovulation, multiple ovulation (MO), pregnancy, multiple pregnancy (MP) rates and synchrony of MO; additionally whether any seasonal effect is evident. Sequential ultrasonic scanning was used to monitor the occurrence of ovulation, within 48h of treatment, in 1291 Thoroughbred mares treated with either 750iu hCG or 1500iu hCG s.c. Ov...
Douglas RH, Umphenour N.Routine measurement of estrogens, testosterone, T4, insulin, FSH, and LH at least four times per year (e.g., during each of the four seasons) may improve the efficiency of stallion management. Benefits may not be realized in the short term but will provide valuable historical data on individual stallions that, when added to other data, will improve ability of management personnel to initiate early treatment and delay or slow declining fertility. This ability will be greatly improved as more data and products become available. There appears to be a relationship between low total estrogen concen...
Tharasanit T, Colenbrander B, Bevers MM, Stout TA.The only gonadotrophin preparation shown to stimulate commercially useful multiple ovulation in mares is equine pituitary extract (EPE); even then, the low and inconsistent ovulatory response has been ascribed to the variable, but high, LH content. This study investigated the effects of an LH-free FSH preparation, recombinant human follicle stimulating hormone (rhFSH), on follicle development, ovulation and embryo production in mares. Five mares were treated twice-daily with 450 i.u. rhFSH starting on day 6 after ovulation, coincident with PGF(2alpha) analogue administration; five control mare...
Esteller-Vico A, Liu IK, Couto S.Vascular degeneration is present in endometrial vessels of multiparous aged mares. The lesions associated with vascular degeneration consist of enlargement, duplication and splitting of the membrana elastica interna and perivascular deposits of elastin. However, there are no similar data available for deep myometrial vessels and the vascular layer. The objectives of the present study were to characterize the status of vasculature in full-thickness uterine necropsy samples and to correlate these findings to endometrial grade, age, and parity. Elastosis was present in myometrial vessels, as well...
Flores Bragulat AP, Ortiz I, Catalán J, Dorado J, Hidalgo M, Losinno L, Dordas-Perpinyà M, Yánez-Ortiz I, Martínez-Rodero I, Miró J, Gambini A.Equus members exhibit very divergent karyotype, genetic plasticity, and significant differences in their reproductive physiology. Despite the fact that somatic cell nuclear transfer and intracytoplasmic sperm injection (ICSI) has gained relevance in the last few years in horses, few reports have been published exploring ovum pick up (OPU) and in vitro maturation (IVM) of cumulus-oocyte complexes (COCs) in donkeys. Yet, some donkey species and breeds are considered endangered, and these assisted-reproductive technologies could help to preserve the genetic of valuable individuals. In this study...
McCue PM, LeBlanc MM, Squires EL.Equine follicle stimulating hormone (eFSH) has been used to induce follicular development in transitional mares and problem acyclic mares, as well as superovulate cycling mares. The most efficacious protocol is to administer 12.5 mg eFSH, intramuscularly, twice daily beginning 5 to 7 days after ovulation when the diameter of the largest follicle is 20 to 25 mm. Prostaglandins are to be administered on the second day of eFSH therapy. Treatment with eFSH is continued for 3 to 5 days until follicle(s) are >or=35 mm in diameter. The mare is subsequently allowed to 'coast' for 36 h, after which hum...
Warnke C, Tuchscherer A, Alm H, Kanitz W, Blottner S, Torner H.The aim of the study was to compare different types of movement pattern and velocities of stallion spermatozoa depending on cryopreservation during breeding and non-breeding season. Ejaculates were collected from four stallions during May (n = 24) and December (n = 24). Parameters of sperm movement were evaluated by computer-aided sperm analysis (CASA) system, and included percentages of motile spermatozoa, different patterns of motility, the velocity, linearity (LIN), amplitude of lateral head displacement (ALH) and beat-cross frequency (BCF). In winter the average percentages of motility wer...
Holtan DW, Nett TM, Estergreen VL.Jugular vein plasma from 13 mares was extracted with diethyl ether and chromatographed on Sephadex LH-20 columns (.5 × 9 cm) after which progesterone and 17α-hydroxyprogesterone (170HP) were quantified by a competitive protein binding radioassay. During pregnancy, progesterone increased (P < .05) from 1.1 ± .4 ng/ml (mean ± SE) on day 0 to 7.5 ± 1.2 ng/ml on day 8 followed by a transient (nonsignificant) decrease to 4.8 ± .4 ng/ml on day 28. From days 28 to 44 progesterone again increased (P < .05) attaining a maximum concentration of 15.2 ± 1.4 ng/ml on day 64. Thereafter progesterone ...
Rohrbach BW, Sheerin PC, Cantrell CK, Matthews PM, Steiner JV, Dodds LE.To determine whether treatment with a preparation of Propionibacterium acnes would improve pregnancy and live foal rates in mares with persistent endometritis. Methods: Randomized placebo-controlled clinical trial. Methods: 95 mares with a cytologic diagnosis of persistent endometritis. Methods: Mares were treated with P acnes or placebo (both administered IV) on days 0, 2, and 6. No attempt was made to alter additional treatments administered by attending veterinarians. Information on breeding history, physical examination findings, results of cytologic examination and microbial culture of ut...
McDonnell SM, Hinze AL.Periodic spontaneous erection and penile movements known as masturbation (SEAM) occur normally at approximately 90 min intervals in awake equids. SEAM in horses has traditionally been misunderstood by many horsemen as aberrant behavior that should be eliminated. Accordingly, it is not uncommon for trainers of performance stallions or managers of breeding stallions to punish SEAM in an attempt to eliminate the behavior. Previous clinical observations and preliminary unsystematic trials had suggested that attempts to stop stallion SEAM may lead to an increase rather than a decrease in SEAM, and ...
Eight mares with third-degree rectovestibular lacerations were treated by a two-stage surgical technique. The rectovestibular shelf was corrected with three parallel 'circular' continuous suture rows distributed along the longitudinal axis of the vagina, and the perineal body was reconstructed with three divergent simple continuous rows. Primary healing of the first-stage surgery occurred in all the mares. Seven of the mares completed the two-stage surgery and primary healing occurred in all of them. One of them returned to endurance racing competition and one was lost to follow-up. The other ...
Leeb T, Sieme H, Töpfer-Petersen E.Our knowledge on the many aspects of mammalian reproduction in general and equine reproduction in particular has greatly increased during the last 15 years. Advances in the understanding of the physiology, cell biology, and biochemistry of reproduction have facilitated genetic analyses of fertility. Currently, there are more than 200 genes known that are involved in the production of fertile sperm cells. The completion of a number of mammalian genome projects will aid in the investigation of these genes in different species. Great progress has been made in the understanding of genetic aberrati...
Alghamdi AS, Madill S, Foster DN, Troedsson MH.When mares are inseminated repeatedly, protein molecules from the seminal plasma (SP) prevent sperm-neutrophil binding and reduced fertility. The molecule(s) responsible for sperm-neutrophil binding is not known and the identification of beneficial SP proteins is complicated by their large numbers and abundant variation. We examined several important aspects of sperm-neutrophil binding to ultimately facilitate the identification and isolation of the molecule(s) responsible. First, we raised anti-equine P-selectin antibodies to determine the involvement of this adhesion molecule in sperm-neutro...
Halo M, Tirpák F, Slanina T, Tokárová K, Massányi M, Dianová L, Mlyneková E, Greń A, Halo M, Massányi P.This study was aimed to determine the impact of different taurine and caffeine combinations on the motility, viability, and oxidative markers of chilled stallion spermatozoa. Each stallion semen sample was diluted in a ratio of 1:2, with various taurine and caffeine concentrations (2.5-7.5 mg/mL taurine + 0.625-1.25 mg/mL caffeine) dissolved in a conventional extender. The control samples (CON) were prepared by diluting ejaculate only using the conventional extender. The motility was analyzed using a CASA system at different time intervals (0, 6, 12, 24, and 30 h) and the viability was evaluat...
Carney NJ, Squires EL, Cook VM, Seidel GE, Jasko DJ.Donor mares of mixed, light-horse breeds, maintained at Colorado State University, provided 104 embryos for immediate transfer (fresh embryos). One hundred and thirty-six additional embryos were collected on various breeding farms in the United States and were shipped to Colorado State University via commercial airlines (cooled embryos). Embryos were harvested 7 d after ovulation, graded, and either transferred into a mare immediately (<1 h) or placed in Ham's F-10 medium plus 10% fetal calf serum in an atmosphere of 5% CO2, 5% O2, 90% N2 and packaged in a passive cooling unit (Equitai...
Farquhar VJ, McCue PM, Carnevale EM, Nett TM, Squires EL.Following induction of ovulation with deslorelin acetate (Ovuplant), gonadotrophin concentrations are reduced in the subsequent cycle, leading to increased interovulatory intervals in some mares. This study determined whether implant removal after 2 days prevented the decrease in gonadotrophin concentrations and follicular growth during the ensuing cycle. Twenty-four mares were randomised equally into 3 groups. Group 1 ovulated spontaneously, Groups 2 and 3 received the deslorelin implant to induce ovulation. Two days after treatment, the implant was removed from Group 3. On Day 10 postovulati...
Papa PM, Guasti PN, De Vita B, Nakazato NG, Maia L, Freitas Dell'Aqua CP, Scheeren VFDC, Segabinazzi LGTM, de Andrade Junior LRP, Silva LFMC....Although stem cell therapy is a promising alternative for treatment of degenerative diseases, there are just few reports on the use of stem cells therapy in horse's reproductive system. This study aims to evaluate the effect of intratesticular injection of bone marrow mesenchymal stromal/stem cells (MSCs) in healthy stallions, and its outcome on seminal parameters and fertility. In Experiment 1, 24 stallions were divided into treatment group (TG) and control group (CG). In the TG, an intratesticular application of MSC was performed, and in the CG, only PBS was used. Measurements of testicular ...
Brogna R, Fan J, Sieme H, Wolkers WF, Oldenhof H.Even though dried sperm is not viable, it can be used for fertilization as long as its chromatin remains intact. In this study, we investigated drying- and temperature-induced conformational changes of nucleic acids and stallion sperm chromatin. Sperm was diluted in preservation formulations with and without sugar/albumin and subjected to convective drying at elevated temperatures on glass substrates. Accumulation of reactive oxygen species was studied during storage at different temperatures, and the sperm chromatin structure assay was used to assess DNA damage. Fourier transform infrared spe...
Álvarez C, Gil L, González N, Olaciregui M, Luño V.The rise of assisted reproduction techniques in equine medicine has fostered investigations that seek to optimize methods to increase fertility rates. Since cryopreservation continues to give low values of viability in stallions, the handling and preservation of the sperm is of vital importance. This reduction of fertility makes it essential for farmers to find new options that ensure reliability in the use of these techniques. The main objective of this study was to assess the effect of INRA 96® (manufactured commercial extender for cooling of Equine semen) as an extender for cryopreservatio...
