Fetal distress during the last third of pregnancy in bitches - evaluation by Doppler ultrasound imaging

Background: Diagnostic ultrasound has revolutionized obstetric practice. Doppler techniques provided in vivo studies of the fetus-placental and uterus-placental circulations, in an increasingly precise manner. The assessment of fetal well-being is essential in obstetric practice, however, in veterinary medicine, there is a deficit of ultrasound parameters related to fetal distress. The main of this research was to determine the hemodynamic characteristics and behavior, through Doppler ultrasonography, of maternal-fetal vessels during the final third of gestation in bitches with fetuses under stress, as well as correlating them with each other and with fetal distress. Materials, Methods & Results: An observational, prospective study was carried out, in which 30 healthy bitches were examined, during the last third of pregnancy, with fetuses under fetal distress. Fetuses were evaluated in 2 stages: (1st): 50-54 days and (2nd): 55-60 days of gestation. All fetuses were calmly assessed, one by one, and fetal heart rate (FHR) was measured 5 times, for at least 3 min, to identify and confirm fetal distress. At least 3 fetuses were evaluated in each bitch and each measurement was performed in triplicate, setting a hemodynamic mean for each value evaluated. The flow pattern in the middle cerebral artery (MCA), internal carotid artery (ICA) and umbilical artery (UA) was evaluated. The analyzed vessel was initially visualized in B mode, followed by evaluation by color and spectral Doppler. The variables observed were: peak systolic velocity (PSV), end diastolic velocity (EDV) and the resistivity (RI) and pulsatility (PI) index, as well as the systole/diastole ratio (S/D). The analysis of RI and PI of the umbilical artery showed a statistically significant difference between the mean values found for the times studied, increasing from time 1 to time 2. For middle cerebral and internal carotid arteries, PI, RI and the relationship systole/diastole (S/D), showed a statistically significant difference between the mean values found for the times studied, decreasing from time 1 to time 2. Discussion: Fetal heart rate (HR) findings are considered normal above 200 beats per minute (bpm), only if preceded by acceleration and deceleration. This fact confirms the presence of fetal stress, by this parameter, for the fetuses in the present study. Corroborating the picture of fetal distress, another study concluded that HR tends to increase up to 20 days before delivery, a fact that did not occur in the study in question, where animals in the same gestational period were evaluated. Recent research has concluded that an elevated umbilical artery PI at 28 weeks of gestation, in the absence of fetal growth restriction or prematurity, is associated with some adverse cognitive findings in 12-year-olds children. In the present study, a progressive increase in this index was observed throughout the final third of pregnancy. Although the pups were not monitored after birth, this data serves as a warning for veterinarians, and can be useful in the assessment and diagnosis of possible postnatal nervous alterations. Like what was found in the present study, a study reported that from the 4th week to birth, the PSV of the umbilical artery (UA) increased almost linearly, with high significance. For the middle cerebral arteries, the PI showed a statistically significant difference between the mean values found for the times studied, however, decreasing throughout the final third of pregnancy.

Standard strain and strain rate by two-dimensional speckle tracking in agoutis (Dasyprocta prymnolopha) anesthetized with ketamine and xylazine

Background: The agouti (Dasyprocta prymnolopha, Wagler, 1831) is a wild rodent widely found throughout America which has stood out as a good animal model for scientific investigations. The aim of this study was to study the cardiovascular function of chemically contained agoutis, by performing echocardiographic examinations and measuring Strain and Strain Rate by Speckle Tracking to obtain reference values for the species and verify the applicability of these animals as models for the study of cardiovascular changes in humans.Materials, Methods & Results: It was selected 16 animals, sedated by the combination of ketamine hydrochloride and xylazine and submitted to transthoracic echocardiography. To obtain the standard measurements, B, M and Doppler mode images were taken. The analysis of the radial and longitudinal myocardial deformation of the left ventricle was carried out. The right parasternal window was used for access to the short cardiac axis and the left for access to the long axis. Six radial profiles of strain (ST) and Strain rate (SR) values were obtained, corresponding to the mean of the values for each segment. A total of 18 myocardial segments were analyzed for each specimen and the mean values were used to compose the statistical analysis. The comparison of the means between the genders did not show statistical difference, being the other statistical treatments based on the total sample of 16 animals. The variables that showed statistically significant correlation coefficients in relation to weight were: LA, LA/AO, HR, AVmax, E’ wave, E/IVRT (P > 0.05). HR showed a positive correlation with IVSd (r = 0.51), EPSS (r = 0.55) and E’ wave (r = 0.68); negative with IVRT (r = - 0.41), A wave (r = - 0.54), AVmax (r = - 0.53) and Pmax (r = - 0.65).[...]

Standard strain and strain rate by two-dimensional speckle tracking in agoutis (Dasyprocta prymnolopha) anesthetized with ketamine and xylazine

Background: The agouti (Dasyprocta prymnolopha, Wagler, 1831) is a wild rodent widely found throughout America which has stood out as a good animal model for scientific investigations. The aim of this study was to study the cardiovascular function of chemically contained agoutis, by performing echocardiographic examinations and measuring Strain and Strain Rate by Speckle Tracking to obtain reference values for the species and verify the applicability of these animals as models for the study of cardiovascular changes in humans.Materials, Methods & Results: It was selected 16 animals, sedated by the combination of ketamine hydrochloride and xylazine and submitted to transthoracic echocardiography. To obtain the standard measurements, B, M and Doppler mode images were taken. The analysis of the radial and longitudinal myocardial deformation of the left ventricle was carried out. The right parasternal window was used for access to the short cardiac axis and the left for access to the long axis. Six radial profiles of strain (ST) and Strain rate (SR) values were obtained, corresponding to the mean of the values for each segment. A total of 18 myocardial segments were analyzed for each specimen and the mean values were used to compose the statistical analysis. The comparison of the means between the genders did not show statistical difference, being the other statistical treatments based on the total sample of 16 animals. The variables that showed statistically significant correlation coefficients in relation to weight were: LA, LA/AO, HR, AVmax, E wave, E/IVRT (P > 0.05). HR showed a positive correlation with IVSd (r = 0.51), EPSS (r = 0.55) and E wave (r = 0.68); negative with IVRT (r = - 0.41), A wave (r = - 0.54), AVmax (r = - 0.53) and Pmax (r = - 0.65).[...](AU)

Electrocardiographic pattern of agoutis (Dasyprocta prymnolopha) chemically contained by the association of ketamine and xylazine

Background: The agouti (Dasyprocta prymnolopha, Wagler, 1831) is an existing wild rodent in almost all of Brazil, usedas a biological model in several scientific studies. Veterinary cardiology has showed great advances in the diagnostic areadue to the possibility of cardiac evaluation by non-invasive methods. For the practice of scientific or handling proceduresin wild animals, chemical containment is essential. Thus, it is important to know the effect of anesthetic protocols on thecardiovascular system, observed through complementary tests, such as the electrocardiogram. The objective of this studywas to describe the computerized electrocardiographic tracing of agoutis chemically contained by the association of Ketamineand Xylazine.Materials, Methods & Results: Eighteen male and female clinically healthy animals, aged among 2 years, submitted todigital electrocardiographic examination, were used. The device used to obtain the tracing was the veterinary electrocardiograph(Electrocardiogram Acquisition Module for Computer) - Brazilian Electronic Technology (TEB). The analysiswas always made from derivation II (DII). Chemical containment was performed by the combination of Ketamine andXylazine, intramuscularly. The results showed that the heart rate for males was on average 113.25 bpm, while for femalesthe value of 124.60 bpm was observed, and there was no significant difference between the genders (P > 0.05). The meanweight of males was 2.31 kg and for females 2.28 kg; there was no statistical difference for this variable (P > 0.05). Forthe QRS duration of 46.14 ± 5.05 ms (males) and 44.66 ± 5.94 ms (females) and PR interval of 79.94 ± 12.01ms (males)and 84.29 ± 12.37ms (females), there was no statistical difference (P > 0.05). The amplitude of the R wave of 0.42 ± 0.31mV (males) and 0.36 ± 0.22 mV (females) showed no statistical difference (P > 0.05). The T wave showed itself bothnegative (10 animals) [...]

Electrocardiographic pattern of agoutis (Dasyprocta prymnolopha) chemically contained by the association of ketamine and xylazine

Background: The agouti (Dasyprocta prymnolopha, Wagler, 1831) is an existing wild rodent in almost all of Brazil, usedas a biological model in several scientific studies. Veterinary cardiology has showed great advances in the diagnostic areadue to the possibility of cardiac evaluation by non-invasive methods. For the practice of scientific or handling proceduresin wild animals, chemical containment is essential. Thus, it is important to know the effect of anesthetic protocols on thecardiovascular system, observed through complementary tests, such as the electrocardiogram. The objective of this studywas to describe the computerized electrocardiographic tracing of agoutis chemically contained by the association of Ketamineand Xylazine.Materials, Methods & Results: Eighteen male and female clinically healthy animals, aged among 2 years, submitted todigital electrocardiographic examination, were used. The device used to obtain the tracing was the veterinary electrocardiograph(Electrocardiogram Acquisition Module for Computer) - Brazilian Electronic Technology (TEB). The analysiswas always made from derivation II (DII). Chemical containment was performed by the combination of Ketamine andXylazine, intramuscularly. The results showed that the heart rate for males was on average 113.25 bpm, while for femalesthe value of 124.60 bpm was observed, and there was no significant difference between the genders (P > 0.05). The meanweight of males was 2.31 kg and for females 2.28 kg; there was no statistical difference for this variable (P > 0.05). Forthe QRS duration of 46.14 ± 5.05 ms (males) and 44.66 ± 5.94 ms (females) and PR interval of 79.94 ± 12.01ms (males)and 84.29 ± 12.37ms (females), there was no statistical difference (P > 0.05). The amplitude of the R wave of 0.42 ± 0.31mV (males) and 0.36 ± 0.22 mV (females) showed no statistical difference (P > 0.05). The T wave showed itself bothnegative (10 animals) [...](AU)

Isolation and characterization of mesenchymal progenitors derived from the bone marrow of goats native from northeastern Brazil

PURPOSE: To characterize bone marrow progenitors cells grown in vitro, using native goats from northeastern Brazil as animal model. METHODS: Ten northeastern Brazil native goats of both genders were used from the Piauí Federal University Agricultural Science Center's (UFPI) - Goat Farming Sector. Bone marrow aspirates where taken from the tibial ridge and seeded on culture plates for isolation, expansion and Flow Cytometry (expression markers - Oct-3/4, PCNA, Ck-Pan, Vimentina, Nanog). RESULTS: Progenitor cells showed colonies characterized by the presence of cell pellets with fibroblastoid morphology. Cell confluence was taken after 14 days culture and the non-adherent mononuclear cell progressive reduction. After the first passage, 94.36% cell viability was observed, starting from 4.6 x 106 cell/mL initially seeded. Cells that went through flow cytometry showed positive expression for Oct-3/4, PCNA, Ck-Pan, Vimentina, and Nanog. CONCLUSIONS: Bone marrow progenitor isolated of native goats from northeastern Brazil showed expression markers also seen in embryonic stem cells (Oct-3/4, Nanog), markers of cell proliferation (PCNA) and markers for mesenchymal cells (Vimentina and Ck-pan), which associated to morphological and culture growth features, suggest the existence of a mesenchymal stem cell (MSC) population in the goat bone marrow stromal cells studied.(AU)