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Summary: This case report describes the diagnosis and surgical treatment of a 12‐year‐old Friesian stallion that presented with colic and was diagnosed with an unilateral abdominal seminoma. The diagnostic work‐up included haematology, blood chemistry, rectal examination and ultrasonography before the tentative diagnosis of a neoplastic intra‐abdominal testicle was made. The mass was removed surgically and diagnosed as a seminoma via histopathology. Regular follow‐up was performed since suspected metastasis was seen on transrectal ultrasonography and laparoscopy. Unfortunately, the patient was subjected to euthanasia 18 months post‐surgery due to clinical deterioration. Post‐mortem examination was performed and confirmed the cause of clinical deterioration was due to metastasis of the previously removed seminoma. Colic is, to the author's knowledge, rarely seen in stallions with an abdominal testicular neoplasm, in contrast to humans and dogs. [ABSTRACT FROM AUTHOR]

Summary: The use of cryopreserved stallion semen is a significant aspect of equine reproduction, despite the tendency for lower per cycle pregnancy rates than cooled or fresh semen. This decreased fertility of thawed frozen semen is due in part to the innate subfertility of the chosen male breeding population, but also to the direct insults to the sperm cell during the freezing and subsequent thawing process. The mare aspect of frozen semen breeding is intensively managed to compensate for the aforementioned damages, and acceptable pregnancy rates can be achieved. Here we describe the stallion semen cryopreservation process including semen collection, expected causes of damage in processing, freezing and thawing, mare management and future directions. [ABSTRACT FROM AUTHOR]

The breeding history of the Einsiedler horse is closely connected with the Benedictine cloister Einsiedeln. In the mid‐nineteenth century, it was decided to use European Warmblood stallions for cross‐breeding and to abandon the selection of stallions. Since that time, it has only been possible to trace back the origin of Einsiedler horses using maternal ancestry information. Here, we collected high‐density genotype data for European Warmblood horses (Selle Français, Swiss Warmblood and Einsiedler) and Franches‐Montagnes horses, the last native Swiss horse breed, to unravel the current population structure of the Einsiedler horse. Using commonly applied methods to ascertain fine‐scale population structures, it was not possible to clearly differentiate the Einsiedler from other European Warmblood horses. However, by means of runs of homozygosity (ROH) we were able to detect breed‐specific ROH islands for the Einsiedler horse, including genes involved in domestication and adaptation to high altitude. Therefore, future breeding activities should involve the screening of these breed‐specific ROH segments, the revival of cryopreserved sperm and the selection of Einsiedler stallions. [ABSTRACT FROM AUTHOR]

Context: Resumption of testicular function after gonadotrophin-releasing hormone (GnRH) immunisation varies among individual animals and some stallions regain fertility only after a prolonged time. Aims: This study evaluated endocrine effects of GnRH immunisation and early subsequent re-stimulation with a GnRH agonist. We hypothesised that GnRH agonist treatment advances resumption of normal endocrine function in GnRH-vaccinated stallions. Methods: Shetland stallions were assigned to an experimental and a control group (n = 6 each). Experimental stallions were GnRH-immunised twice, 4 weeks apart. Each experimental stallion was hemicastrated together with an age-matched control animal when testosterone concentration decreased below 0.3 ng/mL. Three weeks later, daily treatment with the GnRH agonist buserelin was initiated (4 μg/day for 4 weeks followed by 8 μg/day). The remaining testicle was removed when testosterone concentration exceeded 0.5 ng/mL in vaccinated stallions. Blood was collected for LH, FSH, oestradiol and anti-müllerian hormone (AMH) analyses, and testicular and epididymal tissue were conserved for real-time qPCR and histology. Key results: GnRH vaccination reduced blood concentrations of LH and FSH, with a structural deterioration of testicular tissue and disruption of spermatogenesis. Daily buserelin treatment for approximately 60 days partially restored gonadotropin secretion and induced a recovery of the functional organisation of the testicular tissue with effective spermatogenesis. Conclusions: Endocrine testicular function can be restored in GnRH-vaccinated stallions by daily low-dose buserelin treatment. The buserelin treatment protocol may potentially be improved regarding the dose, interval and duration. Implications: Daily buserelin treatment can be recommended for treatment of GnRH-vaccinated stallions with prolonged inhibition of testicular function. GnRH vaccination is used in male horses to reduce sexual behaviour and gonadal function, but the time to regain fertility varies considerably among individual animals. Daily GnRH agonist treatment for approximately 60 days in stallions vaccinated against GnRH successfully stimulated the production of sex steroid hormones and spermatogenesis. This treatment may be recommended for GnRH-vaccinated stallions with persistent inhibition of testicular function and fertility. Image by Camille Gautier. This article belongs to the Collection Dedication to Jim Cummins. [ABSTRACT FROM AUTHOR]

The present work was designed for a thorough investigation into the sperm morphology and morphometry of Kurdish stallions. The semen samples were collected from 10 Kurdish stallions. Three preparations from each ejaculate were stained with eosin–nigrosin (EN), Diff‐Quik (DQ) and Rose Bengal (RB). The area, perimeter, length and width of the sperm head as well as tail length and total sperm length were measured. The parameters ellipticity, elongation, roughness and regularity were calculated. The morphology of sperm was also investigated under scanning and transmission electron microscopes. DQ and RB provided more clarified images for examining sperm structures compared to the EN method. The head length, head width, area and perimeter in EN were significantly higher than those in DQ and RB (p ≤.05). Furthermore, the difference in head width, head area and head perimeter between DQ and RB was not significant (p ≥.05). The tail length and total sperm length in all methods were close together (p ≥.05). The highest percentage of normal sperm was seen in DQ and RB methods (82.55 ± 2.88 and 88.31 ± 5.19) respectively. The highest values for ellipticity, elongation and regularity were found in RB, whereas the highest value for roughness was measured in EN. Tail defects including coiled tails, and folded midpieces were the most frequent. Scanning electron microscope revealed two types of head shapes: heads with round anterior border, and heads with flat anterior border. The results indicated that despite the routine use of EN for morphological assessment of stallion sperm, RB and DQ can be considered for more clarified details of sperm structure including acrosome and midpiece. Furthermore, the Kurdish stallion sperm has morphometric traits in the normal range established for stallions; yet, some traits were larger than those reported for other breeds. It seems that the sperm of the Kurdish stallion has a longer head and tail in comparison with other horse breeds. [ABSTRACT FROM AUTHOR]

The purpose of this case report is to describe and document a rare anatomical variation of a moderator band located in right ventricle of a stallion referred for cryptorchid castration. During routine preanesthetic echocardiography, a thick moderator band was detected crossing the right ventricle. No other cardiovascular abnormalities were identified. Anesthesia and recovery occurred uneventfully. This variation is important not only for anatomy but also for the evaluation of normal heart both during ultrasound and electrocardiographic examination. [ABSTRACT FROM AUTHOR]

Simple Summary: Stallion breeding soundness is indicated for infertility or to evaluate the potential to mate or to produce and ship doses of fresh, refrigerated, or frozen semen. This review describes the methods used to evaluate equine semen and their relation to semen production pathways and fertility. Clinical examination is useful for detecting genital tract pathologies, but also for predicting the expected spermatozoa production. Basic semen evaluation in the laboratory includes analysis of the volume, spermatozoa concentration, motility, and morphology. These factors can be used to evaluate the spermatozoa production and its quality, and predict the efficiency of natural mating and the potential fresh or refrigerated semen dose production. The post-thaw quality of some stallions is below standard, despite good fresh semen quality, requiring methods for predicting this outcome. To overcome this concern and the unresolved infertility cases, biotechnologies offer new opportunities. The potential toxicity of seminal plasma can be investigated, and damaged parts of the spermatozoa can be imaged with specific staining and fluorescent microscopy or flow cytometry. These data will deepen the understanding of stallion infertility and enhance basic semen evaluation. Stallion sperm analysis is indicated for infertility diagnosis, pre-sale expertise, production of fresh or frozen doses, and frozen straw quality control. Various collection methods are described, and numerous assays can be performed on semen. Determining an approach for each of these cases is challenging. This review aims to discuss how to obtain relevant clinical results, answering stallion owners' concerns. Semen can be collected with an artificial vagina on a phantom or a mare, by electro-ejaculation under anesthesia, or after pharmacological induction. The collection method influences the semen volume and concentration, while the total sperm number depends on the testicular production and collection frequency. In the seminal plasma, acidity, pro-oxidant activity, and some enzymes have repercussions for the semen quality and its conservation. Moreover, non-sperm cells of seminal plasma may impact semen conservation. Motility analysis remains a core parameter, as it is associated with fresh or frozen dose fertility. Computer-assisted motility analyzers have improved repeatability, but the reproducibility between laboratories depends on the settings that are used. Morphology analysis showing spermatozoa defects is useful to understand production and maturation abnormalities. Staining of the spermatozoa is used to evaluate viability, but recent advances in flow cytometry and in fluorochromes enable an evaluation of multiple intracellular parameters. Spermatozoa protein expression already has clinical applications, for example, as a fertility and freezing ability predictor. At present, stallion semen analysis ranges from macroscopic evaluation to assessing spermatozoa proteins. However, clinically, all these data may not be relevant, and the lack of standardization may complicate their interpretation. [ABSTRACT FROM AUTHOR]

To improve accuracy in evaluating stallion ejaculates, an antibody‐based, flow cytometric assay for the detection and identification of leukocyte subpopulations (CD4‐, CD8‐, CD21‐, CD172a‐positive cells) in stallion semen (n = 12) was established. For establishment of the assay, native semen was supplemented with blood leukocytes (control: 20% leukocytes, 80% sperm cells) and analysed by flow cytometry. Adding antioxidants (ascorbic acid and butylated hydroxytoluol) to semen immediately after collection inhibited rapid death of lymphoid cells in sperm leukocyte mixtures. In control set‐ups, 27.85 ± 5.7% of events were positive for CD4, CD8, CD21 or CD172a, while in native semen samples, leukocytes were scarce (0.114 ± 0.134%). The most abundant leukocyte subpopulation in semen was of lymphoid origin (CD4‐positive cells [0.015 ± 0.02%]), whereas CD21‐positive cells (B cells; 0.001 ± 0.001%) were virtually absent in ejaculates of fertile stallions. This presented flow cytometric assay for the detection and identification of different leukocyte population in equine antioxidant‐treated ejaculates can be used as an additional tool for spermatological examination in stallions. [ABSTRACT FROM AUTHOR]

Glass wool column filtration (GWCF) selects human, bull, boar, dog and buffalo spermatozoa, but reports in the horse are scarce. Single‐layer colloid centrifugation with Androcoll‐E™ is currently the standard procedure to select good‐quality equine sperm. This study was designed to assess GWCF (50 and 75 mg columns; GWCF‐50 and GWCF‐75, respectively) efficacy to select good‐quality sperm from fresh and frozen–thawed equine semen, and to compare its performance with Androcoll‐E™ colloid centrifugation. Percentage total motile (TM), progressively motile (PM), morphologically normal (MN), osmotically competent (HOS+) and acrosome‐intact/osmotically competent (AI/HOS+) sperm were determined. In studies done with fresh semen samples (n = 17), suspensions subjected to GWCF‐50 showed an improvement (p <.05) in PM and HOS+ sperm after selection. With GWCF‐75, an increase (p <.05) in PM, MN and HOS+ sperm was observed. Results with GWCF were comparable or better than with Androcoll‐E™ selection. Sperm recovery was similar between procedures for all semen parameters. Total sperm count recovery was lower after GWCF‐75 (GWCF‐50 = 60.0; GWCF‐75 = 51.0; Androcoll‐E™ = 76.0 million sperm; median; p =.013), but results on total progressive sperm count were similar (GWCF‐50 = 23.0; GWCF‐75 = 27.0; Androcoll‐E™ = 24.0 million sperm; median; p =.3850). Using frozen–thawed semen samples (n = 16), an improvement (p <.05) in TM, PM, NM, HOS+ and AI/HOS+ sperm was observed in GWCF‐75 filtrates. Results were comparable to Androcoll‐E™ centrifugation, except HOS+ that increased (p <.05) only after GWCF‐75. Recovery was comparable for all parameters in frozen samples. GWCF is a simple and low‐cost procedure that selects equine sperm with a quality comparable to colloid centrifugation with Androcoll‐E™. [ABSTRACT FROM AUTHOR]

Summary: Spermiostasis (or sperm accumulation) is an ejaculatory dysfunction of common occurrence in referral reproductive practice with stallions. The accumulation of sperm in the epididymides, ducti deferens, and ampullae results in ejaculates with a high concentration of degenerated sperm. It is estimated that 5% of light‐breed stallions present this condition; however, the incidence is unknown in ponies as this condition has not been reported in these breeds. The present report describes the diagnosis and management of spermiostasis in a 16‐year‐old Shetland stallion presented for semen collection, evaluation, and cooling test. Semen collection resulted in 73 billion total sperm with necrozoospermia and 67% detached heads. Ten serial semen collections gradually improved sperm motility and morphology. There was no evidence of ampullary plugs in the semen filter throughout the collections. An additional semen collection was procured 48 h after collection 10 for a cooling test. Sodium caseinate cholesterol‐loaded cyclodextrin extender resulted in superior sperm motility compared to the native phosphocaseinate extender up to 48 h post‐cooling in two semen containers. Sixty days after the initial visit, the stallion returned for a semen freezing test. The ejaculate was normozoospermic, and the owner reported that the stallion had satisfactory fertility for live cover after discharge from the hospital. The thermal longevity test of the frozen‐thawed resulted in excellent motility after 120 min of storage at 37°C. In conclusion, herein, we described, apparently for the first time, the occurrence of spermiostasis in a pony stallion. We foresee that other practitioners managing similar clinical cases could have comparable outcomes. [ABSTRACT FROM AUTHOR]

Summary: A 19‐year‐old Thoroughbred stallion developed severe curvature of its penis, preventing intromission, after breeding a mare. The cause of the curvature was found, during ultrasonographic examination of the penis, to be rupture of the trabeculae on the left side of the corpus cavernosum penis (CCP) between the cul de sac of the external preputial cavity and the scrotum, resulting in the formation of a seroma. Aspiration of the seroma performed 13 days after injury, with the horse anaesthetised, largely resolved the deviation. A complication of treatment was excessive belling of the glans penis during erection, which may have been the result of a temporary shunt created between the CCP and the corpora spongiosum penis (CSP) by inadvertently passing the spinal needle used to aspirate the seroma through the CSP. Excessive belling resolved after 3 weeks. [ABSTRACT FROM AUTHOR]

Summary: A 15‐year‐old male Quarter Horse stallion was referred with paraphimosis and suspected exuberant granulation tissue (EGT) of the glans penis. Physical examination revealed a painful, voluminous, pink, irregular, cauliflower‐shaped lesion on the penis. Based on the history, anatomical location and clinical presentation EGT was suspected. Histopathology confirmed the diagnosis with no evidence of neoplasia. To obtain breeding soundness, surgical excision of the EGT and reconstruction of the glans penis was recommended. Following surgical removal of the granulation tissue, the stallion recovered without complications and returned to breeding with satisfactory performance including normal libido and mating behaviour. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to describe placement of a nictitating membrane flap as a treatment for corneal ulceration and bullous keratopathy in two horses. Animals Studied: A 13‐year‐old American Saddlebred mare presented for severe corneal edema, superficial stromal ulceration, and a central bulla of the left eye. A 4‐year‐old Trakhener stallion also presented with a large axial bulla of the left eye with concurrent severe corneal edema and a deep stromal ulcer. Procedure: A complete ophthalmic examination was performed. Samples were obtained for corneal cytology, and both horses were started on aggressive medical therapy. Both underwent general anesthesia for placement of a nictitating membrane flap and a subpalpebral lavage system (SPLS). Results: Corneal cytology for each horse revealed a mixed bacterial population. Moderate Pseudomonas aeruginosa was cultured from the mare, while Aspergillus species and a few Enterococcus gallinarum were cultured from the stallion. The bullae in both horses resolved at 3 and 4 weeks and vision returned in the affected eye 4.5 and 3 months postoperatively at the last follow‐up, respectively. Conclusion: Aggressive medical management with concurrent placement of a nictitating membrane flap is effective to treat bullous keratopathy in two horses. The described treatments could be used to treat horses that develop severe or progressive bullous corneal lesions. [ABSTRACT FROM AUTHOR]

Summary: Background: The Caspian miniature horse (CMH) is a small horse breed, which has not previously been evaluated for ophthalmic diseases. Objectives: The purpose of this study was to describe the ocular findings and to declare the normal ocular parameters seen in a small herd of CMH. Study design: Cross‐sectional study. Methods: Forty‐five Caspian miniature horses (25 mares and 20 stallions) were examined. Complete ophthalmic examination, commensal ocular surface microbiota culture and measurement of the horizontal and vertical fissure length were performed. Results: Mean ± SD age of horses was 52.0 ± 33.9 months (range: 12–122 months). Nine different ocular disorders were observed: dacryocystitis, conjunctivitis, linear keratopathy, Haab's striae, corpora nigra atrophy, iris hyperpigmentation, cataract, peripapillary butterfly inactive lesions and inactive choroiditis were detected. In total, 17 eyes (18.8%) of 12 horses (26.2%) had ocular related lesions. Two horses (4%) had more than one ocular lesion; the lesions were consistent with a diagnosis of either traumatic or recurrent uveitis. No vision loss was detected in these horses despite the identified ocular disorders. Main limitations: Limited number of studied animals. Conclusions: This study reported ocular findings in a small herd of CMH. A minority of horses in the herd had ocular lesions suggesting a history of glaucoma and/or equine recurrent uveitis. [ABSTRACT FROM AUTHOR]

The application of the 'omics' studies in the field of animal reproduction has been aimed at identifying novel biomarkers of fertility since the last few years. When assessing reproductive efficiency in horses, breed should also be taken into account as it can influence semen quality and fertility. Considering the growing interest in metabolomic analysis to evaluate male fertility, we aimed to investigate the metabolomic profile of seminal plasma in two different horse breeds. Twelve healthy stallions, n.6 American Quarter Horse (AQH) and n.6 Italian Draft Horse (IDH) stallions, regularly used for artificial insemination, were included in the study. Two semen collections, performed 30‐day apart, were considered for the assessment of semen parameters including gel‐free volume, spermatozoa (spz) concentration, spz progressive motility and seminal plasma analysis by 1H‐NMR.Semen characteristics differed between IDH and AQH (p <.05) as well as the first cycle conception rate that was higher in AQH than IDH (p =.001). Metabolomic analysis quantified 56 molecules in equine seminal plasma, with 11 metabolites showing different concentrations in IDH compared to AQH (p <.05).This study provided evidence of differences in seminal plasma metabolites' concentrations between studied horse types, highlighting specific metabolomic fingerprints characterizing AQH and IDH sperm. [ABSTRACT FROM AUTHOR]

This is the fourth study in a series dedicated to analyzing the process of historicizing the horse in Native American cultures and it focuses on its representation in two stories: un untitled story told by the Diné and Ghost Stallion, recorded from the Yinnuwok. None of them is a creation story (in the sense of explaining how the first horse was created), but both fall into the category of stories that narrate how the historical legitimacy of the horse was constructed, following a recurrent pattern that first dehistoricizes and then re-historicizes the horse. In this process, the structural identity of the horse, internal and external, is changed though an act of mythicization, which allows it to be logically enculturated in a tribe's narrative. [ABSTRACT FROM AUTHOR]

Simple Summary: Since 2014, the genetic evaluation of the population of Czech sport horses has been based only on the evaluation of results from jumping competitions. The performance test is an integral part of the testing of young horses in the Czech Republic, as is the linear description of horses. The results from both the linear description and the performance test show low to medium heritability for the observed traits. The genetic parameters obtained in this study indicate that the data obtained from the performance test are suitable for inclusion in the genetic evaluation of sport horses in the Czech Republic, as the breeding values would be refined, especially in young mares and stallions. The aim of this study was to estimate the genetic parameters of a one-day performance test together with the linear type traits of 3-year-old warmblood horses. The study of genetic parameters was based on 5958 tested horses in the period 1998–2021. A total of 22 traits of linear description, three quantitatively measured traits, and one summary mark from the performance test were tested. The model equation included the fixed effect of gender and combination effects of classifier–year of evaluation–place. A single-trait animal model was used for the estimation of heritability and genetic variance, while the two-trait animal model was applied for the estimation of variance and covariance between all traits. The heritability of the overall score of the performance test was 0.25. The range for heritability was between 0.04 and 0.33 for the linear type traits and between 0.46 and 0.57 for the quantitatively measured traits. Genetic correlations were between −0.47 and 0.92. The estimated genetic parameters suggest that the results from the performance test can be incorporated into genetic evaluation in the Czech Republic. [ABSTRACT FROM AUTHOR]

Summary: The alterations found in the ejaculate of stallions, obtained through fractionated semen collection, may be used as a diagnostic tool for identifying the origin of the pathology. The occurrence of seminal vesiculitis, lacerations and urethral rents, bulbourethritis, and prostatitis may be accurately identified through the use of fractionated semen collection. However, because findings can at times be vague or misleading, if possible, one should pursue complimentary examinations for a definitive diagnosis. The clinical findings obtained through the fractionated semen collection should be reasonably interpreted by the veterinarian. Thus, we aimed to illustrate the findings obtained through fractionated semen collection in stallions with ejaculate alterations, which may allow the identification of the origin of pathological alterations. [ABSTRACT FROM AUTHOR]

Summary: A 10‐year‐old, 595 kg Irish Warmblood stallion used for showjumping was presented with a marked right forelimb lameness at walk. The horse sustained a dorsal plane fracture of the accessory carpal bone (ACB) when falling with both carpi in flexion. The fracture was repaired by means of computer‐assisted orthopaedic surgery (CAOS) using two cortex screws placed in lag fashion. In a second CAOS procedure, a dorsoproximal fragment of the ACB was removed after further proximal displacement had become apparent. Both surgical procedures were facilitated by the application of a fibreglass cast to immobilise the carpus in extension and to allow for the placement of the patient tracker distant from the surgical site. One year after surgery, the horse had returned to full athletic activity. Neither the antebrachiocarpal joint nor the carpal sheath were distended. Control radiographs and standing cone beam computed tomography showed complete osseous union of the fracture and osteophyte formation on the caudal aspect of the radius and the proximal border of the ACB. [ABSTRACT FROM AUTHOR]

Background: This study is a part of an ample research concerning the genetic history of Hucul horse breed. The genetic analysis studies are part of animal genetic resources management because just start of them we elaborate the strategies for inbreeding management. The itself genetic relationship of a population is the average genetic relationship of all individuals between them, existing at a time. Therefore, this parameter can be described three components: the genetic relationship between stallions, between mother mares themselves and the genetic relationship between stallions and mares. The last component is most important because of the average population inbreeding increases in successive generations. Methods: The research was carried out during 2012-2020. The material are represented by genealogical information from reproductive nucleus of Hucul breed from Lucina studfarm. The sample extracted from population was represented by seven sire stallions and seventy-three broodmares. The method are based on A matrix coefficients. All analysis were performed in the profile laboratories of Animal Sciences Faculties from Bucharest and Timisoara. Result: Between individual average genetic relationship values of stallions with mares, is found significant differences, highlighted by the global test of homogeneity test (F=4.891). These differences allow us to assert that, through stallions selection, is made a reproductive discrimination much more intense than in mares case. The average genetic relationship of the population was calculated at 0.1941±0.0053. [ABSTRACT FROM AUTHOR]

Collection of epididymal stallion sperm offers the opportunity to retain and use genetic material from the males after elective castration or even post mortem. The aim of the present study was to evaluate the effect of the Ringer B. Braun solution on stallion epididymal sperm viability and motility during liquid storage for 72 h at 4 °C and at 20 °C. Eight stallions (3–10 years old) were used in the study. Sperm from the cauda epididymis was harvested immediately after routine castration. The sperm from epididymis was washed out and diluted with Ringer B. Braun solution and with a commercial semen extender which was used as a control. Samples from each horse were divided into two parts: one part of samples was stored at 4 ± 1 °C as recommended for the commercial semen extender, the other one was stored at 20 ± 1 °C. Sperm viability, motility, and pH were checked one hour after collection and dilution, and after 24, 48 and 72 h of incubation. The results of sperm viability, subjective and progressive sperm motility showed slightly higher results in semen samples diluted with Ringer B. Braun solution in one hour compared to the commercial extender, by 2.40 ± 0.49% for viability (P > 0.05), by 0.30 ± 9.92% for subjective motility (P > 0.05) and by 5.70 ± 6.07% for progressive motility (P > 0.05). We suggest that Ringer solution could be used for a short term storage (1–24 h) of equine epididymal semen at a 4 °C temperature. [ABSTRACT FROM AUTHOR]

Papillomavirus (PV) infections may be related to anogenital lesions and cancer development in humans and several other animal species. To date, 11 different PVs have been reported in horses. Among them, a newly described PV named Equus caballus Papillomavirus Type9 (EcPV9) was thus far only reported in the semen of a stallion with penile lesions in Australia. This study reports for the first time the presence of EcPV9 in asymptomatic Italian horses. From July 2020 to January 2022, genital brush samples were collected from 209 horses with no apparent signs of neoplastic disease and no PV-associated lesions, clinically examined at the Didactic Veterinary University Hospital (OVUD) of Perugia and at the Veterinary University Hospital (OVU) of Turin. Brushes were submitted to real-time PCR targeting the EcPV9-L1 region. The first amplification targeted a region of ~116 bp, followed by the amplification and sequencing of ~533 bp of the positive samples. EcPV9-L1 DNA was found in eleven horses (5.3%), all female and mainly English Thoroughbred. Co-infection with EcPV2-L1 was found in 7 out of the 11 EcPV9-L1 positive horses (63.6%). This study contributes to the description of the prevalence of exposure or infection of EcPVs in the horse population in Italy, for which data are still limited. In this regard, here we provide a phylogenetic analysis and the completely reconstructed viral genomes of two Italian EcPV type 9 isolates, as well as four EcPV type 2 obtained from co-infected animals. [ABSTRACT FROM AUTHOR]

Simple Summary: Equine breeding is often based on conformation traits, describing the proportions, shape and joint angles of a horse. These conformations traits are, however, mostly subjectively judged and not measured objectively, affecting the response of selection through lower heritabilities and precision. In this study, we measured joint angles, quantified the variation in shape of 608 Swiss Franches-Montagnes (FM) horses and estimated the heritability of these traits. We found that the poll angle had the highest heritability of all joint angles (h2 = 0.37), and variation in shape describing the type (heavy–light) was also fairly heritable (h2 = 0.36–0.37). Furthermore, the shape of the FM stallions has clearly evolved towards a lighter type from 1940 to 2018 without stabilisation in recent years, risking the loss of the light draught horse type. Phenotyping based on photographs allowed us to improve the accuracy of certain joint angle traits, and to monitor the conformational development of the FM breed. Conformation traits such as joint angles are important selection criteria in equine breeding, but mainly consist of subjective evaluation scores given by breeding judges, showing limited variation. The horse shape space model extracts shape data from 246 landmarks (LM) and objective joint angle measurements from triplets of LM on standardized horse photographs. The heritability was estimated for 10 joint angles (seven were measured twice with different LM placements), and relative warp components of the whole shape, in 608 Franches-Montagnes (FM) horses (480 stallions, 68 mares and 60 geldings born 1940–2018, 3–25 years old). The pedigree data comprised 6986 horses. Genetic variances and covariances were estimated by restricted maximum likelihood model (REML), including the fixed effects birth year, age (linear and quadratic), height at withers (linear and quadratic), as well as postural effects (head, neck, limb position and body alignment), together with a random additive genetic animal component and the residual effect. Estimated heritability varied from 0.08 (stifle joint) to 0.37 (poll). For the shape, the type was most heritable (0.36 to 0.37) and evolved from heavy to light over time. Image-based phenotyping can improve the selection of horses for conformation traits with moderate heritability (e.g., poll, shoulder and fetlock). [ABSTRACT FROM AUTHOR]

Summary: Background: Indirect inguinal hernia (IIH) is the most commonly reported acquired hernia in adult horses. Outcomes following surgical intervention comprising of immediate ventral midline laparotomy (IVML) and simultaneous castration are well known. The outcome following reduction of IIH utilising a noninvasive manual reduction (MR) technique in a large number of horses has not been previously reported. Objectives: To describe a nonsurgical MR technique developed by the authors and to report our long‐term experiences and clinical outcome. Study design: Retrospective study. Methods: Medical records of 89 stallions presenting with IIH and treated with MR were reviewed. Extensive patient data was collected, with cases grouped based on outcome of the MR procedure and whether or not laparotomy was performed. Data on short‐ and long‐term outcome was obtained. Results: Manual reduction was successful in 80 of 89 (90%) horses. Fifty of 89 (56%) horses were treated with MR only and without exploratory laparotomy. In total 29 of 89 (33%) horses underwent IVML and 10 of 89 (11%) delayed ventral midline laparotomy (DVML). Resections were performed in 6 of 89 (8%) horses. Concurrent small intestinal volvulus was diagnosed in 8 of 89 (9%) horses. Horses undergoing DVML following a successful MR had the highest mortality rates during hospitalisation (4/10, 40%). Short‐term survival was 92% (82/89). Ipsilateral reoccurrence of IIH post‐hospital discharge was recorded in 7 of 47 (15%) horses. Overall long‐term survival with a median of 12 years was 72% (34/47). Main limitations: These include the retrospective nature of data collection, lack of standardised pre‐ and post‐MR clinical assessments and a biased Warmblood population. Conclusions: Manual reduction appears to be a feasible nonsurgical technique to reduce IIH in adult Warmblood horses, with favourable survival rates. Individual case assessment is crucial, as delayed laparotomy may increase mortality rates. Suspicion of concurrent small intestinal volvulus or devitalised small intestine always warrants immediate laparotomy following MR. [ABSTRACT FROM AUTHOR]

Erosive and ulcerative lesions of the squamous and glandular gastric mucosa are a common disease of the equine stomach. In the past, these lesions in different regions of the mucosa were summarized as one disease (Equine Gastric Ulcer Syndrome) and research focused mainly on the squamous gastric mucosa. Today, findings raised awareness of different underlying pathologies depending on the gastric region. This led to the development of a more precise terminology and the differentiation in Equine Squamous Gastric Disease (ESGD) and Equine Glandular Gastric Disease (EGGD). However, therapy especially of the glandular regions (EGGD) is challenging as treatment protocols such as omeprazole/sucralfate seem less effective as the effects are on squamous lesions. The retrospective study was performed to investigate the efficacy of a monotherapy with misoprostol in comparison to omeprazole/sucralfate and a combined therapy of omeprazole and misoprostol. Therefore, 67 horses which underwent gastroscopic examination were included in the study. The horses were either presented due to acute colic as an emergency and examined during the hospitalisation or had been referred due to behavioural abnormalities and intermittent mild colic symptoms. The horses had glandular and squamous gastric lesions and the group included 31 geldings, 35 mares and one stallion. 50 of the equine patients were Warmblood horses and 17 of them were ponies. Scoring was performed following suggestions of the Consensus statement of the European College of Equine Internal Medicine (2015) and Banse and Andrews (2019). Findings before and after treatment were evaluated retrospectively. 29 horses were treated with omeprazole (2–4mg/kg q. 24h) and sucralfate (12mg/kg q. 12h), 28 horses were treated with misoprostol (5µg/ kg q. 12h) and 10 horses were treated with omeprazole (2–4mg/kg q. 24h) and misoprostol (5µg/kg q. 12h). Mean duration of therapy was 28 days (omeprazole/sucralfate and misoprostol) and 35 days (omeprazole/misoprostol). The horses were discharged from the clinic after the first gastroscopic examination and respective treatment was done at home by their owners until the follow-up examination. A detailed medication protocol was explained and given to the owners as well as a feeding and management advice. Four horses were excluded from the study because they developed mild colic symptoms and lethargy under therapy with misoprostol. Mean EGGD scores decreased significantly under therapy with misoprostol in all examined localisations as follows: fundus p=0.005, antrum pyloricum p=0.003, pylorus p=0.001. Significant improvements after therapy with omeprazole/sucralfate in the glandular region included exclusively the pylorus (p=0,038). EGGD scores decreased non-significantly after treatment with omeprazole and misoprostol. Post-treatment ESGD scores did not show improvement after the therapy with omeprazole/sucralfate. Monotherapy with misoprostol was superior to omeprazole/sucralfate and omeprazole/misoprostol for ameliorating glandular lesions of the equine stomach. This resembles the results of Varley et al. (2019). There was no worsening of ESGD-lesions following therapy with misoprostol like it has been reported in a study of Pickles et al. (2020). Therapy with omeprazole and sucralfate had only little efficacy on lesions of the glandular mucosa and did not have positive effects on squamous lesions. To date, there is no compound containing misoprostol available for equine veterinary medicine in Germany. The authors highly request further research concerning alternative therapeutical options for horses with EGGD and the improvement of their availability for veterinary medicine in Germany. [ABSTRACT FROM AUTHOR]

A potential source of fertility loss in mares is oviductal dysfunction, potentially caused by masses or debris in the lumen, that may prevent either sperm from reaching the fertilization site or the embryo from reaching the uterus. Recently a novel therapeutic method leading to increased pregnancy results was described by infusing misoprostol, a synthetic prostaglandin E 1 , in the uterus of mares with unexplained fertility problems. In this study, we aimed, after examining the compatibility of misoprostol with semen, to evaluate the pregnancy rate after routine preovulatory deep uterine horn application of misoprostol in clinically normal oestrous mares, which were inseminated in the same cycle. In experiment 1, ejaculates of 10 stallions diluted with INRA 96™ were mixed with different concentrations of misoprostol (0.01 mg/mL, 0.001 mg/mL, 0.0001 mg/mL, and 0.00001 mg/mL) and total semen motility was evaluated immediately, 12, 24, 48, and 72 h later, and compared with a control sample (mixed with NaCl 0.9%). In experiments 2 and 3, 33 privately-owned clinically normal oestrous mares were each allocated to a treatment or control group. Ovulation was then induced with intramuscularly 2.25 mg deslorelin acetate. At the moment of ovulation induction (experiment 2) and 24 h earlier (experiment 3), 0.2 mg misoprostol diluted in 2 mL NaCl 0.9% were applied deep in the uterine horn (treatment groups) and pure 2 mL NaCl 0.9% in the mares of the control groups. Mares were then inseminated 24 h after deslorelin administration and prior to ovulation with commercial chilled-warmed or frozen-thawed semen, as well as immediately after ovulation detection (both types of semen) maximally 48 h after ovulation induction. In experiment 1, regardless of time and compared with the control groups, all solutions with different concentrations of misoprostol had a negative effect on total motility of semen, which was significant for the highest concentrations (0.01 mg/mL: 18.0% reduction, CI = 22–13%, p = < 0.01). We found no beneficial effect of preovulatory uterine treatment with misoprostol on pregnancy rate (OR = 0.45, CI = 0.15–1.31, p = 0.14): in experiment 2, 2/11 (18.2%) mares of the treatment group became pregnant vs. 12/22 (54.5%) mares in the control group (OR = 0.19, CI = 0.03–1.06, p = 0.07), in experiment 3, 5/14 (35.7%) mares in the treatment group vs. 7/19 (36.8%) mares in the control group (OR = 0.95, CI = 0.23–4.02, p = 0.95), respectively. In conclusion, pregnancy rate was not increased in reproductively normal mares with routine preovulatory deep uterine horn application of misoprostol. • We evaluated the effects of preovulatory deep uterine horn misoprostol application. • We found no increase in pregnancy rate after misoprostol treatment. • Misoprostol was well tolerated in the uterus. • Very high concentrations of misoprostol had a negative effect on total semen motility. [ABSTRACT FROM AUTHOR]

Anti-Müllerian Hormone (AMH) has been linked to reproductive tract abnormalities in mares and stallions. This study aimed at evaluating AMH as a biomarker for two reproductive conditions in mares. In the first part of this study, plasma AMH was evaluated as an early indicator of the onset of cyclicity in mares in the transitional period from the anovulatory phase during winter anoestrus to the cyclic phase during the breeding season. Ten mares between 8 and 17 years old were included in the experiment which lasted from mid-February until the end of April. Ovarian activity was monitored with ultrasonography three times per week, the detection of a corpus haemorrhagicum/luteum was documented and antral follicle counts (AFC) were recorded. Blood samples were collected weekly by jugular venipuncture during the whole study period to compare AMH concentrations before and after the first ovulation of the year. The second objective was to evaluate if plasma AMH concentrations in middle-aged mares are linked to fertility and could serve as a prognostic marker in that age group. A total of 41 privately-owned clinically sound mares aged between 12 and 21 years of various breeds were inseminated with fresh or frozen semen. Mares were scanned between day 14 and 20 and the "early pregnancy rate" included only positive pregnancy examinations after the first observed cycle in the season of each mare. Potential associations between the early pregnancy rate in the first cycle and the explanatory factors AMH concentrations, age, status of the mare, stud, development of post-breeding endometritis, number of inseminations and semen type were analysed using logistic regression models. In the first part of the study, correlation between AMH and AFC for the whole study period (P = 0.0002, ρ = 0.55) as well as prior to (P = 0.008, ρ = 0.58) and after the first ovulation (P = 0.0007, ρ = 0.69) were observed. However, AMH concentrations before and after the first ovulation of the year were not statistically different. The second part of the study revealed no association between early pregnancy rate and AMH concentrations or any of the other mentioned factors. In conclusion, this study showed no evidence of a difference between AMH concentrations before and after the first ovulation of the year thus not supporting the use of AMH as a biomarker to predict the onset of cyclicity in mares. We could furthermore not show a relationship between plasma AMH concentrations and early pregnancy rates in this cohort of animals. • Our data did not demonstrate that AMH could predict the onset of cyclicity in mares a highly significant correlation between AMH and antral follicle counts (AFC) was observed. • We found no difference between AMH concentrations before and after the first ovulation. • We found no relationship between AMH concentrations and early pregnancy rates in mares over 12 years old. [ABSTRACT FROM AUTHOR]

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Variations in the appearance of the caudal cervical spine have been acknowledged in horses, particularly with regard to the sixth (C6) and seventh (C7) cervical vertebra. The sixth cervical vertebra can show a symmetrical lamina ventralis at the level of the transverse process. In addition, a unilateral or bilateral transposition of the lamina ventralis from C6 onto C7 is a common finding in horses. In this case, the transposed ventral lamina appears as a bony protuberance at the ventral aspect of the last cervical vertebra. The clinical relevance of this transposition remains unknown; such variations can be associated with severe clinical signs or appear as incidental findings. The aim of the current study was to determine the prevalence of possible transpositions at the level of the last two caudal cervical vertebrae in our population. This retrospective study evaluated standard latero-lateral radiographic images of the cervical spine, acquired with an orthograde beam path. First, the range of possible occurring variations was defined as follows: bilateral ventral lamina at C6, unilaterally missing ventral lamina at C6, bilaterally missing ventral lamina at C6, no bony protuberances at C7, unilateral bony protuberance at C7, bilateral bony protuberances at C7. Then the occurrence of these findings, including concurrent incidence of two or more categories, was analysed. 129 horses fulfilled the study inclusion criteria. The patient collective consisted of 32.6 % mares, 8.5 % stallions, 54.2 % geldings and 4.2 % horses where data concerning the sex was missing. 78.3 % of the examined horses were Warmbloods, 2.3 % Thoroughbreds, 7.9 % Ponies and small horses and 8.1 % of the patients belonged to other breeds. The average age of the horses at the time of radiographic examination was 10 years (range 2–24 years). 17 % of the horses were younger than 5 years of age, whereas most of the patients were at least 5 years or older (79 %). For 4 % of the horses data concerning the age was not retrievable. 20.9 % of the horses showed altered appearance of the last two cervical vertebrae. The most frequently encountered variations consisted in a bilaterally present ventral lamina at C6 (78.8 %) and no bony protuberances at C7 (80.6 %). A combination of these two findings was observed in 79.1 % of the horses. These variations were followed in frequency by unilaterally missing ventral lamina at C6 and unilaterally present protuberance at C7. When considered separately, they occurred with an incidence of 11.6 %, whereas they were found simultaneously in 10.8 % of the horses. In 7.7 % of the patients, symmetrical findings, by means of a bilaterally missing ventral lamina at C6 and the presence of a bilateral protuberance at C7, were detected. Further variations were recorded with a low frequency in the patient group. Moreover, no horse showed a bilateral ventral lamina at C6 associated with the presence of two protuberances at C7. The prevalence of morphological variations at the level of the transverse processes of C6 and C7 encountered in this study (20.9 %) is in line with data mentioned in the current literature. Mostly Warmblood horses were examined in the present study, so a possible relation between breed and the occurrence of the radiologic findings mentioned above could not be determined. Variations occurred among horses of different ages, with 17 % of the patients being younger than 5 years. Since the variations described are congenital, age was not of relevance for the present study. Given the variable appearance of the ventral laminae or caudal tubercle of C6 and the variable occurrence of bony protuberances at C7 observed in the present study, the authors suggest referring to these findings as “morphological variations”. However, multicentre studies, including mature horses examined via standardised techniques are required to elucidate a possible clinical relevance of caudal cervical spine variations. [ABSTRACT FROM AUTHOR]

Different stallions exhibit a high level of variation in the ability of their sperm to survive cryopreservation. A large fraction of stallions show poor post-thaw sperm motility, and their semen is not suitable for commercial freezing. In this study, we hypothesized that the presence of sperm-bound antisperm antibodies (ASAs) was associated with poor cryosurvival of stallion sperm. Our objective was to assess the level of ASA binding to stallion sperm, and determine if it was associated with good or poor sperm cryosurvival. In Experiment 1, cooled shipped semen from 27 stallions was frozen using three commercial semen extenders. Sperm motility, membrane integrity, acrosome integrity and apoptosis were evaluated before and after freezing for each aliquot. In addition, the percentage of ASA-bound sperm was evaluated post-thaw. In Experiment 2, semen from 22 stallions was frozen immediately after collection a single formulation of semen extender. Sperm motility and ASA binding were evaluated post-thaw. The results of both experiments showed similar findings. The frequency of ASA-positive samples was higher among stallions with poor sperm cryosurvival (Exp. 1 and 2 = 6/11, 54.5%) than for good sperm cryosurvival (Exp. 1 = 0/16, 0%; Exp. 2 = 1/11, 9.1%). The percentage of IgG- and IgA-bound sperm was also higher in stallions with poor sperm cryosurvival in both experiments (P < 0.05). Post-thaw sperm motility, velocity and distance parameters were lower in ASA-positive than ASA-negative stallions (P < 0.005). No effect of the semen extender used was observed. In addition, stallions with ASAs had a higher percentage of apoptotic sperm than stallions without ASAs. The presence of sperm-bound ASAs was associated with poor cryosurvival for stallion spermatozoa. Thus, it may be beneficial to evaluate stallions for binding of ASAs prior to freezing to offer and indicator of the prognosis for cryosurvival. • 54.5% of stallions with poor sperm cryosurvival had high ASA binding • Less than 10% of stallions with good sperm cryosurvival had ASA binding • Sperm-bound ASAs were associated with poor cryosurvival for stallion sperm • Identifying ASAs binding prior to freezing may offer a prognosis for cryosurvival [ABSTRACT FROM AUTHOR]

Sperm cryopreservation represents a powerful tool for horse breeding. To improve the efficiency of artificial insemination in the horse using cryopreserved spermatozoa, an adequate understanding of the underlying biophysical properties that affect sperm cryosurvival needs to be reached yet. In this pilot study, we described isolation and analysis of the main fatty acids from sperms of stallions classified as good and poor freezers (7 GF and 5 PF, according to sperm motility and viability, before and after cryopreservation). Fatty acid profiles were only assessed in pre-thaw sperms. Eight main fatty acids were identified, using gas chromatography, and their contents were expressed as percentage of the total lipid content. We found that lauric, myristic and oleic acid (C12:0, C14:0 and C18:1n9c) turned out to be about 2-fold more abundant in the sperm cells of the GFs compared with PFs. Moreover, we described for the first time the presence of a very high amount of a trans geometrical isomer of linoleic acid, linolelaidic acid (C18:2n6t), in pre-thaw PF spermatozoa. Notably, we found in fresh sperms of PF stallions a ratio of unsaturated fatty acids to saturated fatty acids which was twice that of those of GF group, suggesting a positive effect of a high saturated-to-unsaturated fatty acid ratio for the "freezability" of equine spermatozoa. Finally, principal component analysis (PCA) confirmed the relationships between specific fatty acids and cryotolerance of equine spermatozoa, also providing a graphical classification and additional information about the dominant variables governing the classification process. • Linolelaidic acid in equine spermatozoa is a marker of poor freezability and/or defective equine spermatozoa. • Principal component analysis of fatty acid levels allows to make accurate predictions of sperm cryotolerance. • Fatty acid profile may serve as predictor for sperm cryotolerance in horse. [ABSTRACT FROM AUTHOR]

A 9 year old PRE stallion was presented with severe arthrosis of the right front coffin joint causing a severe lameness (grade IV-V/V, AAEP-lameness scale). This severe arthrosis was caused by a septic arthritis after an injection into the coffin joint using unknown substances one year prior to presentation. After the mentioned injection, the horse became increasingly lame and was running a high fever up to 40,5 °C (104,9°F). Treatment at that time was only palliative, without using antimicrobials. At our first visit, one year after the described injection, the horse was in severe pain showing a lameness grade IV-V/V (AAEP lameness scale) with a firm swelling proximal to the coronary band. On the lateromedial radiograph, the coffin joint was profoundly arthritic with a high degree of osteophytes propagating dorsally. The second phalanx (P2) showed serious osteophytes involving the entire dorsal surface of the bone and moderate osteophytes on the palmar surface. The navicular bone had a spike like osteophyte propagating proximally. Soft tissue swelling on the dorsal joint surface could be noticed. On the dorsopalmar view, the appearance of P2 seemed heterogenous due to the overlap of the dorsal and palmar osteophytes and the coffin joint was collapsed laterally. A high degree of osteophyte formation was also noted around the joint. The coffin joint was anesthetized using the dorsal approach with 6mls of Mepivacaine (Mepivacaine hydrochloride 20mg/ ml, Puren Pharma), which showed a significant reduction in the lameness grade (about 70% after five minutes, after ten minutes further amelioration). The synovial fluid appeared watery and the cell count was 0,6 × 109/L, which does not indicate a septic joint. An attempt was made to treat the joint medically using hyaluronic acid (3ml HY 50 Vet. 17mg/ml) and two corticosteroids (triamcinolone acetonide (1ml Triamhexal® 10mg/ml) and dexamethasone (1ml Lipotalon® 2,5mg/ml)). After two weeks the horses’ lameness improved to grade III/V (AAEP lameness scale) for one week. After that the horse deteriorated to its former grade of lameness within eight days. Due to a lack of other options, the decision was made to perform a coffin joint arthrodesis. The surgery was performed in lateral recumbency with the affected joint uppermost. To achieve maximal stability, the decision was made to use the 5.5mm cortical screw system. The drilling direction was established by using hypodermic needles under radiographic guidance. The first incision was made centrodorsal on P2, splitting the extensor tendon along its length for two centimeters. The glide hole in P2 was made from dorsoproximal to palmarodistal. The planned end of the glide hole (at the joint space) was identified radiographically. After that, the thread hole was drilled using radiographic guidance. Finally, the hole was countersunk, the length was measured and tapped creating the threads. Special care was taken to use a length of screw that was able to compress the joint space. The other two screws were inserted in the same fashion lateral and medial to the first one. All the screws were tightened immediately after insertion. The horse was in external coaptation using a half limb cast for 14 days, and then a splint bandage was used for another four weeks. Six weeks after surgery, no substantial bony changes could be found at the operated region. Despite complications like non weightbearing lameness on the non-operated limb for 24 hours, which was due to nerve trauma (we did not consider this complication to be induced by the damage of muscle tissue since there was no swelling, heat or pain in the region of interest), and a non-reduction in the lameness grade on the operated limb for another eight to ten weeks, the described arthrodesis technique led to a substantial success. One-year post operatively, the horse was sound in trot on a straight line but showed a slight lameness on the circle (grade I-II/IV, AAEP lameness scale) and could be used for pleasure riding. One year after surgery, the joint space appeared fused to a high degree and the navicular bone seemed incorporated into P2 and P3 on the lateromedial. The dorsopalmar view established a fusion of about 50% within the coffin joint and a more homogenous texture at the level of P2. An osteophyte was bridging the joint laterally. [ABSTRACT FROM AUTHOR]

Summary: The reproductive performances of livestock play an essential role in the economic management of the farm. The improvement of semen quantity and quality through the use of food supplements that lack substances which are forbidden in animal feeding, or that may have detrimental effects, is an important goal. Maca (Lepidium meyenii) is a plant that has been used for centuries in the Andes for nutrition and fertility enhancement in humans and animals. The aim of this study was to evaluate the effects of food supplementation of stallions with maca during the breeding season on spermatozoa parameters such as DNA fragmentation and shape, which are two predictive indexes of spermatozoa functionality. For this purpose, ejaculate volume, semen gel-free volume, sperm concentration and motility, total sperm count, sperm DNA fragmentation and sperm head parameters (length, width, perimeter, area, shape factor, roughness) were measured in four stallions. Maca food supplementation in stallions during breeding reduced the percentage of spermatozoa with fragmented DNA, increased significantly sperm concentration and exerted an elongation of the spermatozoa head, a condition that is believed to improve spermatozoa functionality, suggesting that food supplementation of maca could be useful in horse breeding during the breeding season. [ABSTRACT FROM AUTHOR]

Study of average performances in a population is very important. Regarding to a population, the average of phenotypic value is equal with average of genotypic value. That minds that the studies of the average value of characters offer us an idea about the population genetic level. The biological material is represented by 177 Hucul horse from HROBY bloodline divided in 6 stallion families analyzed at 18, 30 and 42 months old, owned by Lucina Hucul stood farm. The average performances for thoracic perimeter was 149.58 cm. at 18 months, 160.21 cm. at 30 months old and 166.97 cm. at 42 months old. We can observe a good growth rate from one age to another and significant differences between sexes. The average performances of the character are between characteristic limits of the breed. [ABSTRACT FROM AUTHOR]

The Equine Gastric Ulcer Syndrome (EGUS) is common in horses and of high clinical and economic importance. The objective of this study was to review the current known risk factors and to gain new knowledge about EGUS. In addition, the symptoms previously known from the literature which allow suspicion of a gastric disease were evaluated for their relevance. For this purpose, a multicentric study based on an owner questionnaire was designed, which addresses these factors and signs of disease in detail. At the same time a veterinary report sheet was developed, which enables a uniform classification of the endoscopic findings. It was planned to include all horses presented for gastroscopy in the study. From the total of eight regularly participating clinics and practices in Germany, a total of 133 complete owner and veterinary report questionnaire combinations returned within 20 months. 113 of the evaluable questionnaire combinations were analysed for significant correlations with the occurrence of the EGUS. In the study population examined, the median age of the horses was eleven years (Range). 58% were geldings, 39% mares and 3% stallions. Most horses (67.3%) were used for leisure activities, only 22.1% were sport horses. In the current report, 83.2% of examined horses suffered from EGUS. In 43.4% of the horses both the glandular and the non-glandular mucosa were affected. Only the non-glandular part was affected in 21.2% of the horses and 17.7% suffered from lesions of the glandular mucosa only. The most common reason for presentation was recurrent colic (31.9%). The analysis of the identified risk factors and symptoms for correlation with the presence of gastric lesions showed that the horses from the groups breed: „pony”, horses with „open stables in one group”, „open stables all year round”, „open stables plus grass pasture seasonally”, „hay feeding from a net”, kind of use: Gnadenbrot (keeping of old horses)” and „Omeprazole as prophylaxis during stress „ mostly showed no or only minor gastric findings (EGUS) (p≤0.05). [ABSTRACT FROM AUTHOR]

Following the successful creation of a biobank from two adult Thoroughbred mares, this study aimed to recapitulate sample collection in two adult Thoroughbred stallions as part of the Functional Annotation of the Animal Genome (FAANG) initiative. Both stallions underwent thorough physical, lameness, neurologic, and ophthalmic (including electroretinography) examinations prior to humane euthanasia. Epididymal sperm was recovered from both stallions immediately postmortem and cryopreserved. Aseptically collected full thickness skin biopsies were used to isolate, culture and cryopreserve dermal fibroblasts. Serum, plasma, cerebrospinal fluid, urine, and gastrointestinal content from various locations were collected and cryopreserved. Under guidance of a board-certified veterinary anatomic pathologist, 102 representative tissue samples were collected from both horses. Whole tissue samples were flash-frozen and prioritized tissues had nuclei isolated and cryopreserved. Spatially contemporaneous samples of each tissue were submitted for histologic examination. Antemortem and gross pathologic examination revealed mild abnormalities in both stallions. One stallion (ECA_UCD_AH3) had unilateral thoracic limb lameness and bilateral chorioretinal scars. The second stallion (ECA_UCD_AH4) had subtle symmetrical pelvic limb ataxia, symmetrical prostatomegally, and moderate gastrointestinal nematodiasis. DNA from each was whole-genome sequenced and genotyped using the GGP Equine 70K SNP array. The genomic resources and banked biological samples from these animals augments the existing resource available to the equine genomics community. Importantly we may now improve the resolution of tissue-specific gene regulation as affected by sex, as well as add sex-specific tissues and gametes. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of induced training on the horses' metabolism during an experiment lasting nine weeks where we continually scaled up the load on the horses by three defined stages. Blood was obtained from eighteen horses - two stallions, eight mares and eight geldings. In the experiment, we focused on the biochemical analysis of the blood plasma on multiple mineral profile indicators - Ca, P, Mg, K, Cl and Na, and some other variables (energy, nitrogen, AST, ALT, glucose, urea, creatinine kinase, total proteins). The result showed significant changes between the groups in most indicators. A significant increase in the potassium, phosphorus and calcium and a decrease in the concentrations of magnesium over the course of the experiment were found. For the other indicators, a significant increase in the activities of the AST and ALT out of the other indicators and the fluctuating values in the total proteins were noticed. Summarised, significant changes of multiple indicators were observed in different stages of the experiment. These changes had no visible effect on the horses' organisms throughout entire duration of the experiment and were most probably caused by the muscular work and possible muscular damage during training. [ABSTRACT FROM AUTHOR]

Summary: Testicular trauma is a commonly reported consequence of injury to the scrotum in humans and horses. In the majority of cases in stallions, injury is caused by a kick from a mare during mating. This case report describes a traumatically induced unilateral testicular rupture in a stallion associated with haemoperitoneum and acute, severe signs of abdominal discomfort. Initially, testicular ultrasound and clinical examinations were inconclusive and the clinical signs led to a diagnosis of an inflammatory abdominal disorder, possibly caused by inguinoscrotal herniation. The patient underwent exploratory celiotomy with unilateral orchiectomy at which time no involvement of the gastrointestinal tract was noted (aside from the presence of haemoperitoneum) and the testicular trauma was discovered. As this case demonstrates, testicular trauma should be considered as a differential diagnosis for inguinoscrotal herniation in stallions with clinical signs of discomfort even when there is no history of recent mating. Detailed clinical examination should be performed to establish a diagnosis but may not be conclusive. [ABSTRACT FROM AUTHOR]

The Thoroughbred and Standardbred studbooks are the largest in New Zealand, where the production of horses is pasture based. Each racing studbook is closed, and both have well structured systems in place for recording breeding data. There are significant pressures on the Thoroughbred and Standardbred breeding industries with declining broodmare numbers, and increasingly large book sizes for popular stallions. The breeding season for Thoroughbreds is very short, with disparity between the official breeding season and the physiologic breeding season for mares. These issues are confounded by variable gestation lengths of mares, making it difficult for mares to maintain yearly foaling patterns. However, the reproductive efficiency of Thoroughbred mares is improving, mainly due to veterinary and stud management practices such as those to ensure that dry mares are cycling at the start of the breeding season, foaling mares are bred on foal heat, and that mares are kept in good body condition at breeding. There is also a bias towards breeding younger mares with high fertility in preference to older mares, unless they have desired genetics or successful offspring. Careful management of popular Thoroughbred stallions ensures that large books of mares can be covered by natural service. In contrast, Standardbred stallions are collected every-other-day using an artificial vagina, allowing the breeding of mares at distant locations by artificial insemination, using chilled or frozen semen. Breeding horses kept at pasture under New Zealand conditions requires excellent stud management and veterinary management to achieve good outcomes. [ABSTRACT FROM AUTHOR]

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 parameters were analyzed immediately after light-stimulation (0 min) and after 120 min of incubation at 38 °C. Sperm motility was evaluated using a Computerized Semen Analysis System (CASA), and flow cytometry and different fluorochromes were used to evaluate the integrity and lipid disorder of plasma membrane, mitochondrial membrane potential and intracellular levels of peroxides and superoxides. Irradiation significantly increased the percentages of spermatozoa with high mitochondrial membrane potential (1-1-1 pattern) and the intracellular levels of peroxides (2-2-2 pattern) at 0 min. In addition, sperm kinematic parameters (2-2-2 and 3-3-3 patterns) and percentages of viable spermatozoa with low membrane lipid disorder (3-3-3 pattern) were significantly higher in irradiated samples than in the control at 120 min. Our results indicate that red-light stimulation could help increase the resilience of frozen-thawed stallion sperm to withstand post-thaw incubation at 38 °C for 120 min and that these effects rely on the irradiation pattern. Further research should evaluate whether light-stimulation could also have a positive on fertility rates after artificial insemination. • The effects of red-light stimulation on frozen-thawed stallion sperm depend on the irradiation protocol. • Irradiation of frozen-thawed stallion sperm with red-light has no impact on sperm viability. • Light-stimulation of frozen-thawed sperm partially counteracts the increase in membrane lipid disorder observed at 120 min. • Irradiation of frozen-thawed sperm with red-light induces a transient increase in mitochondrial membrane potential. • Red-light also augments ROS generation immediately after stimulation. [ABSTRACT FROM AUTHOR]

Treatments for seminal vesiculitis have poor outcomes in stallions; thus, the development of alternative strategies is warranted. This study aimed to evaluate fractionated semen collection as a method to restore the fertility of stallions diagnosed with seminal vesiculitis. Eighteen ejaculates from six stallions (three ejaculates/stallion) diagnosed with seminal vesiculitis were harvested in fractions, as follows: Fraction A (FA), the first two jets; Fraction B (FB), the third and fourth jets; and Fraction C (FC), the fifth and remaining jets of the ejaculate. All fractions were subject to standard semen evaluations that were performed in addition to cytology and bacterial aerobic cultures. Fractions were extended and cooled to 5 °C. As a proof of concept, 20 mares (48 estrous cycles, ∼8 cycles/stallion) were bred with 1 billion sperm from FA (cooled at 5 °C for 24 h). In our study, FA had negative bacterial cultures, absent macroscopic or microscopic abnormalities; FB had positive bacterial cultures in two stallions and presence of polymorphonuclear neutrophils (PMNs) in all samples, but with no macroscopic abnormalities; and FC had positive bacterial cultures, purulent appearance, and the presence of degenerated PMNs, just as noted in the whole semen. Overall, post-cooling sperm motility results were superior (P < 0.05) for FA in comparison with FB and FC. First cycle pregnancy rates using FA varied from 66% to 86%. None of the non-pregnant mares developed endometritis. In conclusion, fractionated semen collection can be used to obtain semen free of contamination and to achieve satisfactory pregnancy rates from stallions with seminal vesiculitis. • First two jets from the ejaculate retained high sperm quality postcooling. • Using the sperm rich fraction for inseminating mares yielded 66% to 86% pregnancy rate. • Fractionated semen collection can be used to rescue fertility of stallions affected by seminal vesiculitis. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate differences in the presence of sperm subpopulations in frozenthawed semen in stallions with different freezability. The motility of individual spermatozoa of 24 stallions from 15 breeds was evaluated using computer-assisted sperm analysis (CASA) immediately after thawing (T0) and after 30 min of incubation (T30). In accordance with our previous studies, samples were initially divided based on their total motility into categories of good (GF) and poor (PF) freezers. K-means cluster analysis of kinematic parameters of spermatozoa was used to divide motile sperm (n = 57 630) into three subpopulations. Analysis of variance was used to evaluate differences in the subpopulations between GF and PF stallions at the times of incubation T0 and T30. Statistically significant differences were found in most kinematic parameters between PF and GF stallions as well as between the times of incubation T0 and T30 (P < 0.05). Spermatozoa of good freezers are represented more frequently in the fast and medium fast subpopulations and are faster and more linear than those of poor freezers (P < 0.05). Sperm from PF stallions were more strongly affected by longer incubation. The percentage of sperm in the fast and medium fast subpopulations was lower in samples from PF stallions, but assessment of the motility parameters in particular sperm subpopulations revealed that these sperm had good velocity. Poor freezer samples had lower sperm quality due to a reduced total proportion of motile sperm, and these samples were more sensitive to prolonged time after thawing. Thus, an efficient sperm selection method or a special insemination technique should be used for obtaining doses from stallions with poor freezability. Our study showed that the CASA system and cluster analysis are promising tools for better understanding the significant differences in the individual stallion freezability, and further research should be focused on their application in the field. [ABSTRACT FROM AUTHOR]

Summary: A 9‐year‐old Saddlebred gelding was referred to the University of Wisconsin Veterinary Care for decreased energy levels, weight loss, persistently elevated liver enzymes, hyperglobulinaemia and leukocytosis. Abdominal ultrasonography showed a large volume of peritoneal fluid of mixed echogenicity, and the presence of focally distributed, circular to oval (approximately 1–2 cm), hyperechoic areas within the parenchyma of an enlarged liver. Cytological analysis of the peritoneal fluid revealed sterile neutrophilic/macrophagic inflammation, with haemosiderophages. A liver biopsy confirmed the presence of hepatic amyloidosis and focal fibrosis. Medical therapy with trimethoprim‐sulfamethoxazole for 30 days and long‐term dexamethasone was associated with both a clinical and biochemical response for 7 months, at which time the horse died from presumed hepatic rupture. To the authors' knowledge, this is the first report describing potential successful management of hepatic amyloidosis in a horse. [ABSTRACT FROM AUTHOR]

Summary: Equine coronavirus (ECoV) is considered an emerging enteric virus with reported morbidity rates ranging from 10 to 83% and fatality rates ranging from 7 to 27% in adult horses; a vaccine for ECoV is currently not available. This study investigated the safety, humoral response and viral shedding in horses inoculated with a commercially available modified‐live bovine coronavirus (BCoV) vaccine. Twelve healthy adult horses were vaccinated twice, 3 weeks apart, either orally, intranasally or intrarectally. Two healthy unvaccinated horses served as sentinel controls. Following each vaccine administration, horses were monitored daily for physical abnormalities whilst the onset and duration of BCoV shedding was determined by quantitative PCR (qPCR) in nasal secretions and faeces. Whole blood was collected every 3 weeks to determine BCoV‐specific antibody response. With the exception of transient and self‐limiting changes in faecal character observed in seven vaccinated and one control horse, no additional abnormal clinical findings were found in the study horses. Following the first and second vaccine administration, two and one horse, respectively, tested qPCR‐positive for BCoV in nasal secretions 1‐day post intranasal vaccination. No vaccinated horses tested qPCR‐positive for BCoV in faeces following each vaccine administration. One of the two horses that shed BCoV seroconverted to BCoV after the first vaccine administration and an additional two vaccinated horses (oral and intrarectal) seroconverted to BCoV after the second vaccine administration. In conclusion, the results show that the modified‐live BCoV is safe to administer to horses via various routes, causes minimal virus shedding and results in detectable antibodies to BCoV in 27% of the vaccinates. [ABSTRACT FROM AUTHOR]

Infanticide, related to a stallion's aggression toward a foal sired by another stallion, and feticide related to a new stallion's aggression and/or pheromonal influence (the Bruce effect) inducing loss of a fetus sired by another stallion, a female's counteraction to infanticide, have been proposed for domestic horses (Equus caballus) in human-managed conditions. The aim of the present study was, in conditions close to natural, to investigate the influence of the natural succession of a harem stallion on the mares' subsequent reproductive performance. In a population of semi-feral Konik polski horses observed for 31 years (reproductive seasons) in 8 bands, harem stallion changed 10 times. These changes involved 26 out of 48 mares and 60 out of 609 observed mare-seasons (MS, a year in which a mare experienced a reproductive event). Binary distribution and log link function were assumed. The marginal model included the classification variable (SCH) and the continuous variables (age of the mare and calendar year of reproductive event (birth of a live foal, abortion, foals lost or barrenness) in a given MS was analyzed with generalized linear mixed model. The reproductive fitness of mares and their reproductive success (foal surviving ≥ 1 year), did not differ between MS with and without SCH. Older females were more likely to stay barren, with chances increasing by 21% with each successive year; and less likely to give birth to a foal (13% decrease of chance), and rear a foal to one year of age (12% decrease of chance). The age did not affect the probability of abortions. Of the 26 MS when mares were pregnant when the stallion had changed, there were 25 healthy foals born. For the entire 31 years of monitoring, no aggression toward any foal was observed and all foals that were born in the harem of a new, succeeding stallion successfully reached adulthood. Due to the lack of incidents of infanticide and the lack of evidence suggesting that the presence of a new harem stallion leads to the termination of pregnancies sired by another stallion, the Bruce effect was not confirmed as a biological strategy to reduce investment in pregnancy and potential infanticide in studied population of semi-feral horses. • Change of the harem stallion does not decrease reproductive performance in semi-feral mares. • Infanticide was not observed in semi-feral horses. • Bruce effect was not confirmed as a mares' reproductive strategy. [ABSTRACT FROM AUTHOR]

Summary: Equine viral arteritis (EVA) is a notifiable disease in the UK with potentially serious consequences for horse owners and breeders. Legislation exists under 'The Equine Viral Arteritis Order 1995' to protect the UK from this contagious equine disease. The UK is at risk of introduction of EVA through importation of infected horses or semen. There is however much misunderstanding regarding the importance of EVA and occasionally misinterpretation, specifically on how to protect and manage stallions with vaccination. Issues with changing vaccine datasheet recommendations and vaccine availability have resulted in stallions being inappropriately vaccinated or vaccinations lapsing. This article is aimed at the practicing veterinary surgeon, to update them as to the current status of EVA vaccination and disease screening in horses in the UK and how to avoid some common pitfalls. [ABSTRACT FROM AUTHOR]

To determine the physiologic and behavioral effects and pharmacokinetic profile of hydromorphone administered intravenously (IV) to horses. Prospective, randomized, crossover study. A group of six adult healthy horses weighing 585.2 ± 58.7 kg. Each horse was administered IV hydromorphone (0.025 mg kg–1; treatment H0.025), hydromorphone (0.05 mg kg–1; treatment H0.05) or 0.9% saline in random order with a 7 day washout period. For each treatment, physiologic, hematologic, abdominal borborygmi scores and behavioral data were recorded over 5 hours and fecal output was totaled over 24 hours. Data were analyzed using repeated measures anova with significance at p < 0.05. Blood samples were collected in treatment H0.05 for quantification of plasma hydromorphone and hydromorphone-3-glucuronide and subsequent pharmacokinetic parameter calculation. Hydromorphone administration resulted in a dose-dependent increase in heart rate (HR) and systolic arterial pressure (SAP). HR and SAP were 59 ± 17 beats minute–1 and 230 ± 27 mmHg, respectively, in treatment H0.05 at 5 minutes after administration. No clinically relevant changes in respiratory rate, arterial gases or temperature were observed. The borborygmi scores in both hydromorphone treatments were lower than baseline values for 2 hours. Fecal output did not differ among treatments and no evidence of abdominal discomfort was observed. Recorded behaviors did not differ among treatments. For hydromorphone, mean ± standard deviation for volume of distribution at steady state, total systemic clearance and area under the curve until the last measured concentration were 1.00 ± 0.29 L kg–1, 106 ± 21 mL minute–1 kg–1 and 8.0 ± 1.5 ng hour mL–1, respectively. Hydromorphone administered IV to healthy horses increased HR and SAP, decreased abdominal borborygmi and did not affect fecal output. [ABSTRACT FROM AUTHOR]

Difficult etymologies in Germanic include that of * hanha - 'horse' and * hanhistaz / *hangistaz 'stallion'. Reflections of the latter term are widely evidenced in the Old Germanic dialects while the former is attested onomastically on a late-fourth-century memorial from Burgundy and has also been claimed to be reflected in early runic epigraphy. Both terms appear to continue a remorphologised s -stem * hanhaz ~ *hangisō and have clear Celtic counterparts. The development in Germanic seems to reflect the prehistoric date of the loaning of the s -stem * hanhaz ~ *hangisō from Celtic. [ABSTRACT FROM AUTHOR]

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 ejaculate were not frozen (unfrozen), whereas the remainder were frozen by N2 vapors, plunged in N2 and thawed (frozen-thawed). Rapid cells (RAP; determined by CASA), plasma membraneacrosome integrity (PMAI), high mitochondrial membrane potential (Mpos), low intracellular Ca2+ concentration (Fneg), membrane lipid peroxidation (BODIPY), intracellular ROS concentrations (DCFH, MitoSOX) and chromatin fragmentation (DFI%) were evaluated by flow cytometry in both groups and at intervals during incubation at +37 °C for 24 h. Overall, ROS concentrations and lipid peroxidation were higher and faster (P < 0.0001) in winter versus summer, DFI% was lower in winter versus summer (P < 0.0001), but similar between the two groups within season. There were moderate positive correlations in both seasons between DFI% and MitoSOX, DCFH, BODIPY in both groups, whereas a negative correlation, stronger in winter, was evident between sperm quality (RAP, PMAI, Mpos, Fneg) and BODIPY, DCFH, MitoSOX. There were no differences between seasons for RAP, PMAI, Mpos and Fneg. In conclusion, ROS-related parameters were higher in winter than in summer, without a negative effect on sperm quality. We concluded that increased ROS concentrations were less deleterious to sperm than freezing-thawing. Furthermore, incubation at +37 °C and sequential analysis were useful to assess sperm resistance. • Sperm oxidative status and lipid peroxidation depend on the season. • Overall ROS levels and lipid peroxidation are higher in winter. • Sperm quality does not differ between the seasons, except DNA integrity. • DNA integrity is significantly lower in summer than in winter. • Resistance to DNA damage during incubation differs between two samples and seasons. [ABSTRACT FROM AUTHOR]