Authors:Boglárka Baska-Vincze, Ferenc Baska, and Ottó Szenci
Monitoring fetal heart rate (FHR) and fetal heart rate variability (FHRV) helps to understand and evaluate normal and pathological conditions in the foal. The aim of this study was to establish normal heart rate reference values for the ongoing equine pregnancy and to perform a heart rate variability (HRV) time-domain analysis in Lipizzaner mares. Seventeen middle- and late-term (days 121–333) pregnant Lipizzaner mares were examined using fetomaternal electrocardiography (ECG). The mean FHR (P = 0.004) and the standard deviation of FHR (P = 0.012) significantly decreased during the pregnancy. FHR ± SD values decreased from 115 ± 35 to 79 ± 9 bpm between months 5 and 11. Our data showed that HRV in the foal decreased as the pregnancy progressed, which is in contrast with the findings of earlier equine studies. The standard deviation of normal-normal intervals (SDNN) was higher (70 ± 25 to 166 ± 108 msec) than described previously. The root mean square of successive differences (RMSSD) decreased from 105 ± 69 to 77 ± 37 msec between the 5th and 11th month of gestation. Using telemetric ECG equipment, we could detect equine fetal heartbeat on day 121 for the first time. In addition, the large differences observed in the HR values of four mare-fetus pairs in four consecutive months support the assumption that there might be ‘high-HR’ and ‘low-HR’ fetuses in horses. It can be concluded that the analysis of FHR and FHRV is a promising tool for the assessment of fetal well-being but the applicability of these parameters in the clinical setting and in studs requires further investigation.
Authors:Boglárka Baska-Vincze, Ferenc Baska, and Ottó Szenci
In the equine practice, attempts have been made to examine the fetus in the second and third trimester of pregnancy but all of the available methods have limitations. Until now, transabdominal ultrasonography has been regarded as the most informative examination. This method allows us to measure fetal heart rate, fetal activity as well as the quality and quantity of the fetal fluids. A modified biophysical profile for horses was used by several researchers in the USA from the 1990s as a gold standard. However, it is not sensitive enough and, in the authors’ experience, professionals can face difficulties during its application (e.g. for measuring aortic diameter and fetal breathing movements). In cows, this method was first used for this purpose by a Canadian research group in 2007. They reported that transabdominal ultrasound was promising but showed low sensitivity in this species. The present studies show that birth weight cannot be predicted from fetal aortic diameter measurement in cows as suggested by other researchers. Transabdominal ultrasound needs special equipment (2–3.5 MHz convex transducer) and basic ultrasonographic knowledge; however, we suggest that in most cases it can be performed with the dam placed in a stock and without shaving the examination area. The method provides useful information within 30–40 minutes, enabling the examiner to determine whether or not the fetus is alive and to recognise placentitis or twins. This technique also allows measuring the combined thickness of the uteroplacental unit, and the authors’ ongoing study showed higher normal values in Lipizzaner mares compared to values in other breeds. In conclusion, with the help of advanced techniques, simple and low-cost methods should be developed for the evaluation of the pregnant dam and its fetus to assess fetal viability in the veterinary practice.
Authors:Boglárka Vincze, Orsolya Kutasi, Ferenc Baska, and Ottó Szenci
The aims of this study were to detect physiological changes in blood biochemical parameters throughout gestation, to compare the findings in nonpregnant and pregnant Lipizzaner mares in early-mid and late pregnancy, and to provide reference values for clinical chemistry parameters in this horse breed. A total of 136 venous blood samples were collected from 20 pregnant and 10 nonpregnant (control) asymptomatic Lipizzaner broodmares for biochemical analyses. Twelve parameters (albumin, total protein, urea, triglycerides, glucose, creatinine, alkaline phosphatase, aspartate transaminase, glutamate dehydrogenase, gammaglutamyltransferase, creatine kinase and lactate dehydrogenase) were measured. For the statistical analyses, correlation, analysis of variance and Kruskal–Wallis H-test were used to evaluate the possible associations between parameters. Serum triglyceride levels proved to be significantly different in pregnant mares compared to the control group. Total protein and urea levels significantly decreased, while glucose, triglyceride and glutamate dehydrogenase values increased from approx. the fifth month of gestation until parturition. Four biochemical parameters (albumin, aspartate transaminase, total protein and urea) were lower and three other variables (glucose, alkaline phosphatase and creatinine) were significantly higher in late-term pregnant mares than in mares in early or mid-gestation. It is concluded that reference values not only reflect the species, breed and sex but also the reproductive status of animals.
Authors:Zsófia Bohák, Ottó Szenci, Andrea Harnos, Orsolya Kutasi, and Levente Kovács
Temperament has not been taken into account in previous studies evaluating the stress response to exercise in horses. The aim of the present study was to investigate the cortisol response in Thoroughbred racehorses to a single exercise bout, and to analyse the results based on the basic personality of the horse examined. Twenty healthy Thoroughbred horses were selected for the study based on a 25-item rating questionnaire survey used for characterising equine temperament. Eight temperamental and twelve calm horses took part in the experiment. The horses trotted as a warm-up activity, and then galloped on a rounded sand track. Blood sampling was conducted four times for each horse. Horses with a more excitable temperament showed a higher cortisol response to the test (P = 0.036). In conclusion, cortisol levels in response to a mild intensive exercise can be affected by temperament in horses. Serum cortisol may be a relevant marker to quantify individual temperamental differences in racehorses.
Authors:Ottó Szenci, Kamal Touati, Noelita Melo De Sousa, Jean-Luc Hornick, Gijsbert Cornelis Van der Weyden, Marcel Antonie Marie Taverne, and Jean-François Beckers
The aim of this study was to further develop and extensively describe a surgical technique in order to realise long-term fetal blood sampling in the bovine species. Eleven Holstein–Friesian 6- to 8-month pregnant cows (4–10 years old) were used for this study. Gestational age on the day of surgery varied from approximately 180 days (n = 1) to 240 days (minimum: 232 days, maximum 252 days; n = 10). The fetal medial tarsal artery was catheterised in pregnant cows with a polyvinyl catheter in dorsal recumbency under general anaesthesia. Although 5 out of 11 operations (45.5%) performed between 232 and 252 days of gestation were lost due to different causes mainly associated with peritonitis and septicaemia, the mean interval between operations and calvings was 42.5 days (between 27 and 95 days). It is important to emphasise that a well-trained surgical team is needed for bovine fetal cannulation in order to be able to decrease the risk factors during the operations. Due to the fact that after 5 unsuccessful cases none of the pregnancies were lost, this skill can be reached, and our technique can enable bovine fetal blood sampling for long-term endocrinological and physiological investigations before and during parturition.
Authors:Liliana Rytel, Anna Snarska, Slawomir Gonkowski, Joanna Wojtkiewicz, Ottó Szenci, and Przemyslaw Sobiech
Neuropeptide Y (NPY) is a neuronal active substance taking part in the regulation of gastrointestinal (GI) tract activity. This study used retrograde neuronal tracing and immunofluorescence methods to analyse NPY-positive neurons located in superior cervical ganglion and supplying the cervical oesophagus in the pig. The presence of NPY was observed in 30% of all neurons supplying the part of oesophagus studied. Probably the number of Fast Blue (FB) positive cells depends on the area of the wall injected with FB and the fragment of oesophagus studied. Therefore, the obtained results indicate that the described peptide is an important factor in the extrinsic innervation of this part of the GI tract.
Authors:László Könyves, Ottó Szenci, Viktor Jurkovich, Lászlóné Tegzes, Attila Tirián, Norbert Solymosi, Gyula Gyulay, and Endre Brydl
The objective of this study was to determine some metabolic and other factors predicting the risk of postpartum uterine disease (PUD), and the effects of puerperal metritis (PM) on metabolic status, reproduction and milk yield were analysed. A total of 105 Holstein-Friesian cows were included, and sampled on day < −14 prepartum and days 4, 10–14, 28–35 and 56–63 postpartum for metabolic tests. From day 4 the development of PUD, and from days 28–35 the ovarian activity was monitored. When grade ≥ 1 + ketonuria was present on day 4 postpartum, this indicated a higher probability of PUD [odds ratio (OR) 2.64; P < 0.05] including PM occurring on days 10–14 (OR: 2.65; P < 0.05). Plasma nonesterified fatty acid (NEFA) concentrations > 0.200 mmol/l on days < −14 prepartum indicated a higher risk of uterine diseases (OR: 3.44; P < 0.05). The odds of PUD increased, depending on whether a body condition score (BCS) loss of ≥ 1.0 occurred between days < −14 and 28–35 (OR: 2.82; P < 0.05), between days < −14 and 10–14 (OR: 4.79; P < 0.01) or between days 10–14 and 28–35 (OR: 10.81; P < 0.01). PM was more probable (OR: 27.3; P < 0.001) in cows with retained placenta. The risk of uterine diseases was lower in multiparous than in primiparous cows (OR: 0.29; P < 0.01). PM increased the risk of ovarian inactivity between days 28 and 35 (OR: 2.83; P < 0.05). Cows affected with PM (PM+ cows) showed lower milk production on day 4 (kg; P < 0.05) and lower milk production (P < 0.05), milk fat and milk protein production (kg; P < 0.01; P < 0.01) in the first 100 days of lactation than did PM− cows.
Authors:Boglárka Vincze, András Gáspárdy, Levente Kovács, Ervin Albert, Luca Kézér, Ferenc Baska, and Ottó Szenci
Transabdominal ultrasonography has been shown to be a useful and reliable method for assessing fetal well-being in horses and cattle. To test the applicability of fetal aortic diameter measurement in cattle, 44 late-term pregnant cows and heifers were examined 21 to 0 days prior to calving. Mean fetal aortic diameter was 2.07 ± 0.14 cm and mean fetal heart rate (FHR) was 109 ± 17 bpm. Three dead calves were dissected and their aortic diameter was measured in a water bath. The mean birth weight (n = 44) was 39.9 ± 5.8 kg. There was a significant negative correlation between FHR and fetal aortic diameter. However, although some studies have shown that fetal aortic diameter strongly correlates with birth weight in near-term horses and cattle, in this study there was no correlation between fetal aortic diameter and birth weight in Holstein-Friesian cows and heifers irrespective of whether the fetus was born alive or dead.
Authors:Attila Répási, Zoltán Szelényi, Jenő Reiczigel, Árpád Bajcsy, András Horváth, and Ottó Szenci
Primiparous and multiparous lactating crossbred dairy cows (after Day 40 postpartum) with a mature corpus luteum (CL) (diameter of ≥ 17 mm determined by ultrasonography) and having a follicle with a diameter of ≥ 10 mm were treated with natural prostaglandin F2α (n = 80). Those from the cows that showed oestrus within 5 days after treatment were inseminated (Group 1: n = 39). Other group of cows showing oestrus without treatment (Group 2: n = 41) were inseminated and served as controls. The ovaries of each cow were scanned by transrectal ultrasonography from the day of detected oestrus (Day −1p.m.) until ovulation, to measure the changes in the areas of the CL and the largest follicle and to determine the occurrence of ovulation. Although no significant differences were found between the treated and untreated cows in terms of a reduction in the area of the corpora lutea and of an increase in the area of the dominant follicles, the mean area of these follicles in Group 2 was somewhat greater than in Group 1. The highest conception rate was achieved if AI was performed at the same day as ovulation occurred in both groups (conception rate in treated group was: 62.5%, in untreated group: 66.6%, respectively) between Day 0a.m. to Day 0p.m.. In Group 1, 54.5% conception rate has been achieved if ovulation occurred between Day 0p.m. to Day 1p.m., or 50% between Day 1p.m. to Day 2p.m. after AI, and 53.3% and 44.4% in Group 2, respectively. The conception rate for cows that ovulated before AI in Group 2 was 25%. No ovulation occurred in 7 cows until Day 2p.m. after AI and none of them became pregnant. The overall conception rate was approximately 50% in both groups, but when the cows had ovulated too early or too late relative to the time of AI, the conception rate was significantly lower, thus determination of the optimal time for AI is of great practical importance in dairy herds.
Authors:Péter Tóth, Csaba Horváth, Viktória Ferencz, Krisztina Nagy, Noémi Gligor, Ottó Szenci, and Gábor Bodó
In the first part of this methodological study eleven metacarpi of 9 skeletally normal horses were examined from 4 directions by dual energy x-ray absorptiometry (DXA). The differences between the dorsopalmar-palmarodorsal and lateromedial-mediolateral (opposite sites) bone mineral density (BMD) values were found to be nonsignificant. In the second part of the study the precision of the Norland XR-26 densitometer was tested by measuring 34 metacarpal bones and 34 proximal phalanges, each of them three times, from a single direction. The difference between the individual measurements of the first phalanges and of the metacarpal bones originating from the right or the left side of the same horse were not significant, nor did the age or breed have a significant effect on BMD or bone mineral content (BMC). However, both BMD and BMC are greater in the metacarpal bones than in the proximal phalanges and are higher in geldings than in mares or to stallions, while the BMD or BMC values of mares and stallions did not differ from each other significantly. These data point to the necessity of further BMD studies in a higher number of patients.