Uterine and umbilical resistance index and fetal heart rate in pregnant bitches of different body weight.

The aim of this study was to compare uterine and umbilical artery blood flow and fetal heart rate (FHR) in small, medium and large body weight (BW) dogs during the second half of pregnancy. Purebred pregnant bitches were assigned to one of the following groups according to their BW: small (S; ≤10 kg), medium (M; 11-25 kg) and large (L; >25-45 kg). Uterine and umbilical Doppler and M-mode ultrasonography was conducted every 10 days from Day 30-60 (Day 0 = first day of gestation). From Day 40, uterine and umbilical artery resistance index (RI) progressively and differentially decreased in the three groups (P < 0.01) being less in L than S bitches (P < 0.01). Litter size but not maternal BW (P > 0.1) affected uterine RI on Days 40 (r = 0.39; P < 0.01) and 50 (r = 0.41; P < 0.01). Conversely, on Day 60, maternal BW (r = 0.61; P < 0.01) had an effect on uterine RI while litter size did not (P > 0.1). Fetal heart rate increased from Day 30-50 and decreased to the time of parturition (P < 0.01) without differences among groups at any time point (P > 0.1). Uterine and umbilical blood flow differentially increased throughout mid- and late-pregnancy in breeds with large and small BW. These differences were affected by litter size on Days 40 and 50, and by maternal BW on Day 60. Conversely, during this same period, FHR did not vary among BW groups. Physiological variations should be considered when gestational ultrasonic examination is interpreted in different BW bitches.

Uterine two-dimensional and Doppler ultrasonographic evaluation of feline pyometra.

The aim of this study was to compare uterine two-dimensional and Doppler ultrasonographic parameters in queens suffering from pyometra from those in early pregnancy. Secondly, the effect of the presence of clinical signs of systemic illness on these parameters was also described. Fourteen post-oestrous queens, with uterine luminal content in the absence of embryos were included. According to their outcome (pyometra surgery or parturition), the queens were retrospectively assigned to one of the following groups: Pyometra (PYO; n = 7) or pregnant (PRG; n = 7). In all the queens, two-dimensional and Doppler ultrasound examinations of the uterus were performed. The presence or absence of clinical signs of systemic illness was recorded. The widest cross-sectional diameter (UD), uterine wall thickness (WT), uterine lumen contents (LC) and uterine artery resistance index (RI) were measured. Uterine horn diameter was higher in PYO group than in PRG group (p < 0.05), while WT (p > 0.1) and LC (p = 0.09) did not differ between groups. Values of RI for PYO and PRG groups were 0.61 ± 0.03 vs 0.53 ± 0.09 (p < 0.05), respectively. PYO cats suffering from clinical signs of systemic illness showed larger UD than those without signs (p < 0.01). It is concluded that two-dimensional and Doppler ultrasound might be useful to distinguish queens suffering from pyometra from those in early pregnancy. Secondly, the clinical signs of systemic illness were associated with a larger UD.

Ultrasonographic assessment of maternal cardiac function and peripheral circulation during normal gestation in dogs.

The aim of this study was to describe changes in cardiac morphology, systolic function and some peripheral hemodynamic parameters during normal pregnancy in dogs. Twenty healthy bitches, 10 pregnant (PG) and 10 non-pregnant controls (CG), were evaluated every 10 days using echocardiography from day 0 of the estrus cycle to parturition or to day 65 for the PG and CG groups, respectively. Systolic blood pressure (SBP) and uterine artery resistance index (RI) were also assessed. Throughout the study, the shortening fraction and cardiac output increased up to 30% vs. 5% (P<0.01) and 45% vs. 2% (P<0.01) in the PG and CG groups, respectively. In contrast, SBP and RI diminished up to 20% vs. 1% (P<0.01) and 29% vs. 0% (P<0.01) in the PG and CG groups, respectively. In conclusion, a decrease in afterload, an increase in cardiac output and cardiac hypertrophy appear to be the result of the hemodynamic modifications occurring during pregnancy in dogs.

A combination of oral cabergoline and double cloprostenol injections to produce third-quarter gestation termination in the bitch.

To assess the efficacy and safety of a combined cabergoline and cloprostenol protocol to terminate third-quarter pregnancy, 22 pregnant bitches that ranged from 35 to 45 days after mating were randomly assigned to a treatment group (n=13) or to an untreated control group (n=9). The animals were monitored for 12 days, and pregnancy termination was confirmed by ultrasound examination. Twelve of the 13 treated bitches aborted within 9 days of the initiation of treatment (mean 4.6 days). Only mild side effects were observed. The control animals had normal gestational courses, as did the bitch that did not respond to the therapy. This combination of drugs appeared to be a practical, safe, and efficient abortifacient when used in third-quarter pregnancies.