University of Veterinary Science

About: University of Veterinary Science is a education organization based out in Pyinmana, Myanmar. It is known for research contribution in the topics: Population & Receptor. The organization has 597 authors who have published 650 publications receiving 14262 citations.

Heart rate and heart rate variability in the pregnant mare and its foetus

Abstract: Abortion and preterm birth of foals are major reasons for reproductive losses in the horse. Risk pregnancies require close supervision so that adequate treatment can be initiated in time. The aim of this study was to determine normal values in heart rate (HR) and heart rate variability (HRV) of the pregnant mare compared to her foetus and to detect physiological changes during ongoing gestation. In mares, the RR interval decreased from 1480±29 ms on day 270 of pregnancy to 1190±58 ms on day 330 of pregnancy (p<0.05). In contrast, foetal RR interval increased during the same time period from 611±23 ms on day 270 of gestation to 756±25 ms on day 330 of gestation (p<0.05). Concomitantly, maternal HR increased and foetal HR decreased. No further changes in RR interval occurred during the last 10 days before foaling, neither in the mare nor the foetus. In the last hours preceding parturition, maternal RR interval was lower than at all times earlier in pregnancy (average of 1037±13 ms) but did not change during this time. Maternal HRV did not change during gestation. Marked changes in HRV occurred only during the last minutes of foaling. Then, all HRV variables increased significantly (standard deviation of beat-to-beat interval: p=0.01, root mean square of successive beat-to-beat differences: p<0.01). The cardiovascular system of pregnant mares adapted to the demands of ongoing pregnancy with an increase in HR. We have no evidence that in healthy mares, pregnancy is a major stressor.

Circadian changes in blood ionized calcium, sodium, potassium, and chloride concentrations and pH in cattle.

Abstract: Objective To explore diurnal variation in blood ionized calcium, sodium, potassium, and chloride concentrations and pH in pregnant dairy cows. Animals 14 dairy cows in their third or later pregnancy approximately 6 weeks before expected parturition. Procedure Throughout a 24-hour period, blood samples were taken at 2-hour intervals and analyzed for ionized calcium (iCa2+), potassium (K+), sodium (Na+), and chloride (Cl-) concentrations and pH. Paired t-tests were used to compare initial and final values. Circadian changes were tested by use of repeated-measures ANOVA. Additionally, a nonparametric analysis was performed for each animal to determine minimal and maximal values for the variables. Results Significant differences were not detected between initial and final values of any variable. Repeated-measures ANOVA indicated significant diurnal fluctuations in all variables. With the exception of Cl- concentration, nonparametric analysis of individual values also revealed significant changes over time. Conclusions and clinical relevance The magnitude of daily fluctuations does not make it necessary to standardize time of sample collection for routine diagnostic examination of blood iCa2+, Na+, and Cl-concentrations and pH. However, it may be important to standardize time of sample collection in comparative studies in which more discrete differences may be identified.

Some characteristic features of the biotransport of the cytostatic agent 1,6‐dibromo‐1,6‐dideoxy‐dulcitol

Abstract: Aspects of the biological transport of cytostatically active 1,6-dibromo-1,6-dideoxydulcitol (DBD) were studied using 82Br-labelled material on dogs and Yoshida tumorbearing rats. Thirty-five per cent of the DBD dose was excreted in the urine within 12 hours. Besides unchanged DBD, metabolites containing C-Br bonds could also be detected in the urine. In vivo, the 50% decomposition time of the C-Br bonds in DBD is about 5 to 6 hours. One hour after administration of DBD, more than 50% of the persisting dose had entered the cells. Accumulation of the drug in the tumor tissue could not be demonstrated. A fraction of the dose enters the enterohepatic circulation.