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Occlusal ridges of equines appeared in the evolutionary process of the species to increase its capacity of grazing and trituration. The difference in hardness of dental tissues (cementum, dentin, and enamel) and masticatory pressure on the occlusal surface of the hypsodont tooth promote the appearance of sharp occlusal ridges. The aim of this study was to measure and compare the height of the occlusal ridges (HOR) of the fourth premolar (Triadan 408) before and after odontoplasty. Ten Mangalarga Marchador mares aged 5 to 12 years, under extensive management, were evaluated by measuring the HOR in Triadan 408, using plaster models before, immediately after (D0), 15 days (D15) and 50 days (D50) after odontoplasty. Immediately after the procedure the HOR was only 21.9% of the HOR before the occlusal equilibration; however, in 15 days after odontoplasty, 65.9% of HOR was already reestablished and 80.3% after 50 days of the procedure. HOR in the buccal side resurfaced before the lingual HOR, suggesting a higher masticatory pressure of these buccal points. Results of the present study indicate that 15 days after the dental treatment, equines already have food trituration capacity, since HOR is apparent on the occlusal surface of the premolars that underwent odontoplasty.

Cristas oclusais de equinos surgiram no processo evolutivo da espécie para aumentar sua capacidade de pastejo e trituração. A diferença na dureza dos tecidos dentários (cemento, dentina e esmalte) e a pressão mastigatória na superfície oclusal do dente hipsodonte promovem o aparecimento de cristas oclusais afiadas. O objetivo deste estudo foi medir e comparar a altura das cristas oclusais (HOR) do quarto pré-molar (Triadan 408) antes e após a odontoplastia. Dez éguas Mangalarga Marchador de cinco a 12 anos, sob manejo extensivo, foram avaliadas pela mensuração da HOR no Triadan 408, utilizando-se modelos de gesso antes, imediatamente após (D0), 15 dias (D15) e 50 dias (D50) após a odontoplastia. Imediatamente após o procedimento, a HOR era de apenas 21,9% da HOR antes do equilíbrio oclusal; entretanto, em 15 dias após a odontoplastia, 65,9% da HOR já estava restabelecida e 80,3% após 50 dias do procedimento. HOR na face vestibular ressurgiu antes da HOR lingual, sugerindo maior pressão mastigatória nestes pontos vestibulares. Os resultados do presente estudo indicam que 15 dias após o tratamento odontológico, os equinos já apresentam capacidade de trituração dos alimentos, uma vez que a HOR é aparente na superfície oclusal do pré-molar que foi submetido à odontoplastia.

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BACKGROUND: Epididymal sperm cryopreservation represents the ultimate option to preserve spermatozoa of valuable stallions. OBJECTIVE: The study aims to evalute whether single layer centrifugation (SLC) prior to cryopreservation or after post-thawing improves the quality of stallion epididymal sperm. MATERIALS AND METHODS: Epididymal sperms of stallions were harvested (N=20). Sperm samples were subjected to treatments: conventional centrifugation, SLC prior to cryopreservation (SLC-PC) or SLC post-thaw (SLC+). All samples were cryopreserved, thawed and evaluated. SLC+ were thawed, single layer cenrifuged and resuspended in freezing extender (SLC+F) or cooling extender (SLC+C). Total motility, progressive motility, morphology, mitochondrial functionality, membrane integrity and DNA integrity were evaluated. RESULTS: SLC-PC and SLC+F yielded higher total motility, while SLC+F yielded the highest progressive motility. Mitochondrial functionality was significantly higher in all SLC groups. Membrane integrity was higher in SLC-PC. The percentage of morphologically normal spermatozoa was higher in SLC-PC and SLC+F. CONCLUSION: SLC prior to cryopreservation or post-thaw improves the quality of stallion epididymal spermatozoa. When SLC is performed post-thaw, freezing extender is the best medium to resuspend the pelleted semen.

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Transient endometritis is a normal consequence of breeding and results from uterine contamination with both semen and bacteria. The modulation of the inflammatory response with the use of isoflupredone has been proposed as efficient for the treatment of endometritis by increasing pregnancy rates. The aim of the current study was to determine the effects of isoflupredone on nitric oxide (NO) levels in uterine samples from mares susceptible to persistent postbreeding endometritis, presenting or not the infectious process. Seven consecutive estrous cycles were induced in 11 mares, being the first one used as control (no treatment). All mares were submitted to the following four treatments: treatment 1: control, treatment 2: glucocorticoid (GC) treatment (20 mg isoflupredone acetate) every 12 h, for three consecutive days, treatment 3: infected treatment (intrauterine infusion of 1x109 CFU/ml Streptococcus equi subsp. zooepidemicus), treatment 4: combination of GC + infected treatment (infusion of bacteria 24 h after the first GC treatment). At 12 h after the end of each treatment, uterine samples were collected by flushing and NO was determined. After nitrate reduction, total nitrite was determined by spectrophotometer. No significant differences on nitric oxide concentration were verified by analysis of variance in the different experimental groups. It is concluded that the use of isoflupredone did not alter the nitric oxide concentration in uterine flushing’s from susceptible mares 12 h after treatment.

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Transient endometritis is a normal consequence of breeding and results from uterine contamination with both semen and bacteria. The modulation of the inflammatory response with the use of isoflupredone has been proposed as efficient for the treatment of endometritis by increasing pregnancy rates. The aim of the current study was to determine the effects of isoflupredone on nitric oxide (NO) levels in uterine samples from mares susceptible to persistent postbreeding endometritis, presenting or not the infectious process. Seven consecutive estrous cycles were induced in 11 mares, being the first one used as control (no treatment). All mares were submitted to the following four treatments: treatment 1: control, treatment 2: glucocorticoid (GC) treatment (20 mg isoflupredone acetate) every 12 h, for three consecutive days, treatment 3: infected treatment (intrauterine infusion of 1x109 CFU/ml Streptococcus equi subsp. zooepidemicus), treatment 4: combination of GC + infected treatment (infusion of bacteria 24 h after the first GC treatment). At 12 h after the end of each treatment, uterine samples were collected by flushing and NO was determined. After nitrate reduction, total nitrite was determined by spectrophotometer. No significant differences on nitric oxide concentration were verified by analysis of variance in the different experimental groups. It is concluded that the use of isoflupredone did not alter the nitric oxide concentration in uterine flushings from susceptible mares 12 h after treatment.(AU)

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The objective of this retrospective study was to evaluate the effect of management strategies aiming to improve animal well-being on pregnancy and embryonic death (ED) rates. Breeding records of a cohort of 1206 Thoroughbred mares brought to a stallion station facility, to be bred with the stallions housed there, were evaluated during ten breeding seasons. Mares were blocked according to management strategies in two groups: Stress and Relax. Strategies used to improve animal well-being (Relax group) were as follows: stopping the teasing routine, reducing or eliminating stall confinement, reducing the number of mares per group and maintaining herd stability during the breeding season. In barren mares, the pregnancy rate was higher in the Relax group (91.8%) when compared to the observed in Stress group (84.7%). However, no difference in pregnancy rates were observed (Stress = 85.2% vs. Relax = 86.2) in foaling mares. ED rate was higher in barren and foaling mares of the Stress group mares (25.5% and 26.8%, respectively) compared with the Relax group (16.1% and 14.7%, respectively). No significant differences were observed on foal heat pregnancy rate between groups; yet, the embryo loss on foal heat was significant reduced in Relax mares (Relax = 8.7% vs Stress = 24.5%). In conclusion, management strategies aimed to reduce social stress can reduce early pregnancy losses and the average cycles per pregnancy, improving reproductive performance in mares.

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Mesenchymal stem cells (MSCs), because of their immunomodulation and trophic activities, in addition to their capacity to regenerate damaged tissues, have potential for treatment of many diseases. The success of stem cell therapies depends, in part, on the method of cell delivery, which should provide wide cell distribution and homing in to injured sites. The objective of the present study was to developing a novel strategy for delivery of MSCs into the uterus of mares with endometrosis (degenerative alteration of uterine glands and surrounding stroma). Endometrosis was confirmed in all mares (N = 6) used in this study. To trace multipotent equine adipose tissue-derived MSCs (eAT-MSCs) in endometrial tissue, before transplantation, cells were stained with a fluorescent dye. During a synchronized estrus, the eAT-MSCs (2 × 10(7) diluted in 20 mL of sodium chloride 0.9%) were inoculated into uterus using a simple technique, similar to artificial insemination (AI) in mares. At 7 and 21 days after transplantation, homing of fluorescently labeled eAT-MSCs was observed by confocal microscopy of uterine biopsies collected from the uterine body and in both uterine horns, including glandular and periglandular spaces, in three of four treated mares. Herein, we propose a new method of MSCs delivery in uterus of mares with endometrosis, which was minimally invasive and technically simple.

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