Gestational echobiometry in brachycephalic bitches using high-definition ultrasonography / Ecobiometria gestacional em cadelas braquicefálicas utilizando ultrassonografia de alta-definição

The objective of the present study was to obtain echobiometric values for the most important canine maternal-fetal tissues using high-definition ultrasonography (HDUS) trying to update the formulas for predicting gestational age. Twelve healthy bitches of brachycephalic breeds weighing 7-13kg and aged one to four years were included. The fetuses were analyzed every day using conventional and high-definition ultrasonography from the eighth day after artificial insemination until the day of delivery, using the ACUSON S2000/SIEMENS ultrasound equipment and specific software. Embryonic and fetal structures; diameter of the embryonic vesicle; length of the embryo; biparietal diameter, abdominal length and kidney height; length of the femur, humerus, scapula, radius, and tibia; thickening of the stomach wall; adrenal length; and cardiac size were measured. These variables were correlated with gestational and adjusted tested according to regression models. The results obtained (P<0.001) for: lateral diameter of the gestational sac (R2=81.8%); length of the embryo (R2=85.7%); biparietal (R2=99.1%) and abdominal diameter (R2=97.2%); thickness of the gastric wall (R2=86.9%); length of the femur (R2=96.6%), radius (R2=97.5%), humerus (R2=96.5%), scapula (R2=95.8%) and tibia (R2=97.3%); kidney length (R2=95.8%) and height (R2=96.0%); adrenal length (R2=89.6%); heart length (R2=93.0%) and height (R2=91.5%) of the canine fetuses showed significant correlation with gestational days. This allowed monitoring fetal growth and estimation of age with high accuracy in different gestational periods.(AU)

O objetivo do presente estudo foi obter valores ecobiométricos para os tecidos materno-fetais caninos, usando a ultrassonografia de alta definição (HDUS), desenvolvendo fórmulas para prever a idade gestacional das cadelas. Doze cadelas saudáveis de raças braquicefálicas pesando 7-13kg e com idades entre um e quatro anos foram incluídas. Os fetos foram analisados diariamente com ultrassonografia convencional e de alta definição, do oitavo dia após a inseminação artificial até o dia do parto, utilizando o equipamento de ultrassom ACUSON S2000/SIEMENS e software específico. Estruturas embrionárias e fetais; diâmetro da vesícula embrionária; comprimento do embrião; diâmetro biparietal, comprimento abdominal e altura renal; comprimento do fêmur, úmero, escápula, rádio e tíbia; espessamento da parede do estômago; comprimento adrenal; e tamanho cardíaco foram medidos. Essas variáveis foram correlacionadas com o teste gestacional e ajustado de acordo com os modelos de regressão. Os resultados obtidos (P<0,001) para: diâmetro lateral do saco gestacional (R2=81,8%); comprimento do embrião (R2=85,7%); diâmetro biparietal (R2=99,1%) e abdominal (R2=97,2%); espessura da parede gástrica (R2=86,9%); comprimento do fêmur (R2=96,6%), rádio (R2=97,5%), úmero (R2=96,5%), escápula (R2=95,8%) e tíbia (R2=97,3%); comprimento do rim (R2=95,8%) e altura (R2=96,0%); comprimento adrenal (R2=89,6%); o comprimento do coração (R2=93,0%) e a altura (R2=91,5%) dos fetos caninos apresentaram correlação significativa com os dias gestacionais. Isso permitiu monitorar o crescimento fetal e estimar a idade com alta precisão em diferentes períodos gestacionais.(AU)

Gestational echobiometry in brachycephalic bitches using high-definition ultrasonography

ABSTRACT: The objective of the present study was to obtain echobiometric values for the most important canine maternal-fetal tissues using high-definition ultrasonography (HDUS) trying to update the formulas for predicting gestational age. Twelve healthy bitches of brachycephalic breeds weighing 7-13kg and aged one to four years were included. The fetuses were analyzed every day using conventional and high-definition ultrasonography from the eighth day after artificial insemination until the day of delivery, using the ACUSON S2000/SIEMENS ultrasound equipment and specific software. Embryonic and fetal structures; diameter of the embryonic vesicle; length of the embryo; biparietal diameter, abdominal length and kidney height; length of the femur, humerus, scapula, radius, and tibia; thickening of the stomach wall; adrenal length; and cardiac size were measured. These variables were correlated with gestational and adjusted tested according to regression models. The results obtained (P 0.001) for: lateral diameter of the gestational sac (R2=81.8%); length of the embryo (R2=85.7%); biparietal (R2=99.1%) and abdominal diameter (R2=97.2%); thickness of the gastric wall (R2=86.9%); length of the femur (R2=96.6%), radius (R2=97.5%), humerus (R2=96.5%), scapula (R2=95.8%) and tibia (R2=97.3%); kidney length (R2=95.8%) and height (R2=96.0%); adrenal length (R2=89.6%); heart length (R2=93.0%) and height (R2=91.5%) of the canine fetuses showed significant correlation with gestational days. This allowed monitoring fetal growth and estimation of age with high accuracy in different gestational periods.

RESUMO: O objetivo do presente estudo foi obter valores ecobiométricos para os tecidos materno-fetais caninos, usando a ultrassonografia de alta definição (HDUS), desenvolvendo fórmulas para prever a idade gestacional das cadelas. Doze cadelas saudáveis de raças braquicefálicas pesando 7-13kg e com idades entre um e quatro anos foram incluídas. Os fetos foram analisados diariamente com ultrassonografia convencional e de alta definição, do oitavo dia após a inseminação artificial até o dia do parto, utilizando o equipamento de ultrassom ACUSON S2000/SIEMENS e software específico. Estruturas embrionárias e fetais; diâmetro da vesícula embrionária; comprimento do embrião; diâmetro biparietal, comprimento abdominal e altura renal; comprimento do fêmur, úmero, escápula, rádio e tíbia; espessamento da parede do estômago; comprimento adrenal; e tamanho cardíaco foram medidos. Essas variáveis foram correlacionadas com o teste gestacional e ajustado de acordo com os modelos de regressão. Os resultados obtidos (P 0,001) para: diâmetro lateral do saco gestacional (R2=81,8%); comprimento do embrião (R2=85,7%); diâmetro biparietal (R2=99,1%) e abdominal (R2=97,2%); espessura da parede gástrica (R2=86,9%); comprimento do fêmur (R2=96,6%), rádio (R2=97,5%), úmero (R2=96,5%), escápula (R2=95,8%) e tíbia (R2=97,3%); comprimento do rim (R2=95,8%) e altura (R2=96,0%); comprimento adrenal (R2=89,6%); o comprimento do coração (R2=93,0%) e a altura (R2=91,5%) dos fetos caninos apresentaram correlação significativa com os dias gestacionais. Isso permitiu monitorar o crescimento fetal e estimar a idade com alta precisão em diferentes períodos gestacionais.

Local α1-adrenergic blockers: An alternative for sheep cervix dilation?

To facilitate transcervical artificial insemination in sheep, the effects of local treatment with α1-adrenergic receptor antagonists on cervix dilation and hemodynamics were evaluated. Ewes (n = 7) were subjected to oestrous synchronisation every 40 days and assigned to treatments in a Latin square experimental design (seven animals × seven periods) with a factorial treatment arrangement (A × B), Factors A (prazosin or tamsulosin) and B (1, 2, or 4 mg/animal). Ewes of the six treatment groups (P1, P2, P4, T1, T2, and T4) were administered α1-adrenergic receptor antagonists while those of the control group (CG) were administered only α1-adrenergic antagonist carrier agent. Distance that the transcervical catheter penetrated without cervical resistance, mean arterial pressure, and uterine artery dopplerfluxometry were evaluated before and after 30 min, 1, 2, 4, 8, and 10 h of treatment. Catheter penetration distance was greater in ewes of the T4 and P4 groups (P < 0.01), with there being a positive correlation between dose and distance (r = 0.243). The penetration distance was similar (P = 0.84) for treated groups, with the greatest penetration occurring 2, 4, and 6 h after treatment (P < 0.01). The passage into the uterine lumen was greater (P = 0.013) in ewes of the P4 (17.9 %) and T4 (19.6 %) groups. There were no effects on blood pressure or uterine blood flow (P> 0.05). These preliminary results indicate there are benefits of treatment with 4 mg/animal of tamsulosin or prazosin in catheter passage through the sheep cervix 2-6 h after administration without hemodynamic effects.

Changes in testicular size, echotexture, and arterial blood flow associated with the attainment of puberty in Dorper rams raised in a subtropical climate.

There is a paucity of information on the relationships of testicular morphology, echotextural attributes, and blood flow dynamics with pubertal development of rams raised in a subtropical climate. Forty-five Dorper rams (24 rams aged 8-11 months and 21 rams aged 12-24 months) were examined using a portable ultrasound scanner connected to a 7.5-MHz transducer. Computer-assisted analyses of testicular ultrasonograms utilized commercially available Image ProPlus® analytical software. Spectral Doppler scans of testicular arteries were performed immediately after scrotal (B-mode) ultrasonography to determine peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI = [PSV-EDV]/PSV), and pulsatility index (PI = [SPV-EDV]/mean velocity) of the blood vessels. The length of the testes (9.7 ± 0.3 compared with 9.0 ± 0.2 cm) and scrotal circumference (33.3 ± 0.5 compared with 31.8 ± 0.4 cm) were greater (p < 0.05) but testicular depth (4.5 ± 0.1  compared with 4.9 ± 0.08 cm) was less (p < 0.05) in sexually mature compared with peripubertal rams. [Corrections added on 9 Jan 2019 after initial online publication: The testicular size values in the sentence were corrected.] There were no differences (p > 0.05) between the two age groups of Dorper rams in blood flow indices of testicular arteries. Mean numerical pixel values (100.5 ± 4.1 compared with 89.2 ± 4.8) and pixel heterogeneity (25.6 ± 0.6 compared with 23.6 ± 0.5) of testicular parenchyma were greater (p < 0.05) in peripubertal than in postpubertal rams. Semen volume was negatively correlated with PI of testicular arteries (r = -0.57, p = 0.04). In summary, the attainment of sexual maturity in the rams of the present study was associated with significant changes in testicular length and depth, scrotal circumference, and parenchymal echogenicity/hetrogeneity but not in testicular volume and blood perfusion rates. Testicular artery PI can be used to predict the volume of ejaculate in rams.

Acoustic radiation force impulse (ARFI) elastography to asses maternal and foetal structures in pregnant ewes.

The aim of this study was to evaluate the stiffness of foetal lungs, liver, kidneys and placentomes by acoustic radiation force impulse (ARFI) elastography in ovine and to correlate obtained findings with foetal development. Twenty-four ewes were included, and tissue stiffness of foetal lung, liver, kidney and placentome was measured beginning with 10th gestational week by qualitative-quantitative ARFI elastography. A total of 33 healthy lambs were born. Qualitative elastographic analysis permitted to classify maternal and foetal tissues elasticity in decreasing order as follows: placentome, kidney, liver and lung. Regarding quantitative ARFI elastography data, shear wave velocity (SWV) of foetal lung and liver varied. The lung SWV decreased gradually from the 16th to the 21st gestational week (R2  = 0.80; p < 0.001), while liver SWV increased gradually from the 14th to 21st gestational week (R2  = 0.80; p < 0.001). In contrast, the kidneys and placentomes SWV's remained constant through gestation (p = 0.076; and 0.34). ARFI elastography was shown feasible for evaluation of maternal and foetal tissues stiffness in the ovine model. It can be used to demonstrate pulmonary and hepatic stiffness modifications during foetal development.

Influence of estrous cycle and gestation on cardiovascular system of bitches.

The purpose of this study was to evaluate the consequences of the estrous cycle and gestation on the cardiovascular system of bitches evaluated through echocardiographic assessment. Fifteen healthy pregnant bitches aged 2 to 6 years and weighing 8.8 ±â€¯2.5 kg were included in the study. Heart rate and blood pressure were clinically evaluated. M-mode, spectral, and tissue Doppler-echocardiography assessments were performed during the anestrous and estrous stages, every 15 days during pregnancy (15, 30, 45, and 60 days), and 45 days postpartum. The data for evaluated variables were submitted for statistical analysis. Heart rate (P = 0.286) and systolic blood pressure (P = 0.686) were not changed as a result of pregnancy or estrus, while ejection fraction (P = 0.0016) and fractional shortening (P = 0.00004) changed. The variables transmitral flow, isovolumetric relaxation time, aortic and pulmonary flow, and some variables related to myocardium movement obtained via tissue Doppler assessment varied (P < 0.05) among the reproductive periods studied. In conclusion, gestation resulted in changes in echocardiography variables, and consequently, on maternal hemodynamics, with myocardial contractility increasing during pregnancy, resulting in greater systolic efficiency and ventricular compliance.