Fertility problems of mares on a well-managed breeding farm with thoroughbred stallions have been ascribed mostly to contamination of the reproductive apparatus of females with pathogens, particularly those of bacterial origin. This study presents a summary of the frequency of bacterial pathogens isolated from 437 cervical swabs which were collected from English thoroughbred mares intended for mating between 2008-2014, as well as of resistance tests of these pathogens to seven commonly used antibiotics as follows: penicillin, gentamicin, tetracycline, sulfisoxazole, cefotaxime, marbofloxacin and enrofloxacin. In addition, the study reports the changes in the levels of plasma oestradiol and progesterone determined two to three days before and two to three days after the first postpartum ovulation in mares with positive and dubious bacteriological findings and percentage of barren mares and mares that conceived at first, second and third post-partum ovulations. It was observed that 21.5% of mares were barren even after the third post-partum cycles. The oestradiol levels determined two to three days before the first post-partum ovulation were significantly lower in mares positive for pathogenic microflora in their reproductive apparatus compared to mares with the dubious findings (25.1 ± 5.8 pg/ml vs. 69.7 ± 18.3 pg/ml; P < 0.05), while the mean progesterone levels did not differ significantly but displayed a rather wide range in positive mares (from 0.08 to 1.38 ng/ml) compared to dubious mares with only small variations (0.12 ± 0.03 ng/ml). Moreover, of the total number of cervical swabs taken shortly before the first post-partum oestrus from all the mares intended for mating as many as 69.7% were contaminated with pathogenic microflora (positive findings). Saprophytic microorganisms only (the dubious findings) were isolated from 29.7% of swabs. From the 307 positive swabs, we could identify 40.4% positive for β-haemolytic streptococci and 20.4% positive for Escherichia coli, the pathogens implicated in causing reproductive disorders. Tests of antibiotic resistance of the investigated pathogens revealed that both Gram-positive and Gram-negative bacteria showed high susceptibility to antibiotics such as cefotaxime, marbofloxacin and enrofloxacin. On the other hand, both these bacterial groups showed high resistance to routinely used broad-spectrum antibiotics, such as penicillin and tetracycline. Because further research is required for a full understanding of the mechanism of pathogenesis of post-breeding endometritis, we can only hypothesise that uterine contamination with pathogenic microflora, particularly with β-haemolytic streptococci and coliform bacteria, diagnosed before the first post-partum ovulation, could negatively affect the hormonal regulation of oestrus and result in mare fertility problems.

The aims of this study were to determine the concentrations of calcium, magnesium, phosphorus, chlorine, potassium, sodium, urea, total cholesterol, triacylglycerols, non-esterified fatty acids, total protein, creatinine, total bilirubin, aspartate aminotransferase, insulin, insulin growth factor 1, and glucose in the blood serum and to monitor the body weight changes in nine clinically healthy Lipizzan mares at weekly intervals within 2 weeks before and 2 weeks after the parturition. A significant body weight loss (P < 0.01) was found in the mares after the foaling. The peak of insulin growth factor 1 concentration in serum was reached at the day of parturition and similar patterns were revealed for the concentrations of insulin and glucose. After parturition, all these indices were significantly decreased. The concentrations of phosphorus and triacylglycerols were decreased, while the concentrations of potassium and sodium were increased at the day of parturition. Moreover, the concentration of non-esterified fatty acids was increased at the day of parturition (P < 0.05) with a tendency to higher values even on the 7 th day postpartum. Other studied indexes remained relatively stable throughout the transition period. We can conclude that periparturient mares face some degree of negative energy balance with concomitant significant homeostatic and homeorhetic changes. For this reason, our results can be used as a basis for reference values and a diagnostic tool to examine the health status in horses during the transition period. Horse, metabolic indices, transition phase, homeostatic changes, homeorhetic changesThe peripartal period is a very challenging interval of life of dams due to the decreased feed intake in the late gestation that is accompanied by the increasing metabolic demands of the foetus, and then after the parturition due to the onset of milk production to cover the nutritional requirements of the offspring as well as for the postpartum (p.p.) recovery of the dam. It is well understood mostly from research performed on high-yielding animals, that all these events trigger different cascades of metabolic reactions as a part of the adaptation mechanisms of the organism of the dam concomitant to the transition from the pregnant non-lactating state to the non-pregnant lactating state. From the physiological point of view, the endocrine changes in mares around the parturition have been well described but only limited literature data are available in the field of biochemistry. It is known that especially during the transition period, both pregnant and lactating mares are highly vulnerable to various health disorders which could lead to different productive and reproductive problems (Reed et al. 2010). For this reason, it is recommended to perform a set of metabolic blood tests in dams over the transition to determine the dynamics of homeostatic and homeorhetic changes, and thus predict the course of puerperium in these animals. In general, the assessment of energy balance (non-esterified fatty ac...

The aims of this study were to analyze the indices of mineral, enzymatic, protein and lipid metabolism, and the antioxidant status in horses trained for jumping after prolonged exercise. A total of 10 Slovak warmblood horses (aged 6-15 years) trained for jumping were used. Blood samples were taken before and after the jumping training (control), immediately after prolonged exercise and after the following 36 h of rest. Control samplings showed no signs of exerciseinduced dehydration, but an increase of haematological indices, increased concentration of lactate and increased activity of lactate dehydrogenase whose changes may be indicative of splenic blood efflux and activation of anaerobic metabolism. On the other hand, changes of biochemical indices (such as: increased alanine aminotrasferase, lactate dehydrogenase and creatine phosphokinase, decreased K and Fe, increased malondialdehyde and glutathione peroxidase) that are indicative for the muscle membrane leakage, oxidative stress and electrolyte imbalances, and alterations of intermediary metabolism were found due to the non-standard prolonged exercise. Although this study demonstrates that trained horses adapted to a certain exercise regimen are exposed to oxidative and metabolic stress by non-standard prolonged workload, further research is required to assign an appropriate resting regime needed to compensate for the induced biochemical changes. Equine, metabolic indices, antioxidants, performanceAs published by Robert et al. (2010), studies on endurance and prolonged exercising horses often report only descriptive results, and physiological explanation of changes responsible for the observed alterations is rarely provided. It is probably due to the alterations of plasma volume which vary in horses subjected to the different physical performance on a variety of environmental conditions, as reviewed by Carlson (1987). Hypovolaemia caused by exercise-induced dehydration is a problem to which mostly endurance and prolonged exercising horses must respond.It is well known that during prolonged exercise in horses, loss of water and electrolyte via sweat may develop exhaustion with hypovolaemia and electrolyte changes, which subsequently result in fatigue, metabolic disturbances, fractures and even death. For example, positive correlation between exercise intensity and gastric ulceration severity was proven by Bezdekova et al. (2005). Physiologically speaking, correct interpretation of the metabolic changes after prolonged or endurance exercise in horses is required, because it can help the veterinarian, trainer, or owner to choose appropriate training and post-exercise recovery as well as adequate dietary supplementation.The aim of this study was to determine the influence of a non-standard prolonged exercise in horses trained for jumping on chosen haematological and biochemical indices which are related to mineral, enzymatic, protein and lipid metabolism and to the antioxidant status. Material and Methods AnimalsTen clinically healthy Slovak warmblood ...

This study aimed to clarify the therapeutic effect and regenerative potential of the novel, amino acids-enriched acellular biocement (CAL) based on calcium phosphate on osteochondral defects in sheep. Eighteen sheep were divided into three groups, the treated group (osteochondral defects filled with a CAL biomaterial), the treated group with a biocement without amino acids (C cement), and the untreated group (spontaneous healing). Cartilages of all three groups were compared with natural cartilage (negative control). After six months, sheep were evaluated by gross appearance, histological staining, immunohistochemical staining, histological scores, X-ray, micro-CT, and MRI. Treatment of osteochondral defects by CAL resulted in efficient articular cartilage regeneration, with a predominant structural and histological characteristic of hyaline cartilage, contrary to fibrocartilage, fibrous tissue or disordered mixed tissue on untreated defect (p < 0.001, modified O’Driscoll score). MRI results of treated defects showed well-integrated and regenerated cartilage with similar signal intensity, regularity of the articular surface, and cartilage thickness with respect to adjacent native cartilage. We have demonstrated that the use of new biocement represents an effective solution for the successful treatment of osteochondral defects in a sheep animal model, can induce an endogenous regeneration of cartilage in situ, and provides several benefits for the design of future therapies supporting osteochondral defect healing.

The aim of this study was to monitor and evaluate the seasonal changes on selected reproductive parameters in mares. Ninety-six mares of different breeds, aged 3 to 23 years were evaluated during the breeding season 2015–2018 at the Equine clinic at University of Veterinary Medicine and Pharmaco­logy in Košice, Slovakia (48°42´N, 21°15´E). The beginning of the estrus was determined by history or observation, mares were examined every 6 hours, blood for progesterone analysis was taken from the jugular vein. Correlation analyses were performed using both the Pearson and the Spearman correlation coefficient. Statistical analysis was performed using the functions of Microsoft Excel and GraphPad Prism. The day length (r = -0.708, P<0.0001) and the average ambient temperature (r = -0.754, P<0.0001) had a statistically significant effect on the duration of estrus. The shortest estrus was recorded in July with day length of 15 hours 40 minutes at an average temperature of 21.4 ± 0.52 °C, with duration 4.67 ± 0.58 days. The longest estrus was recorded in April with day length of 11 hours 48 minutes at average temperature of 6.9 °C. The environmental factors did not affect the size of the preovulatory follicles, the concentration of progesterone, the internal changes of uterus and the external manifestations of estrus.