Establishment of a new equation to estimate gestational age in female dogs.

The objectives of this study were to propose a statistical model to predict the behaviour of the thickness of the uteroplacental junction as a function of the gestation period in female dogs and to determine the relationship between the thickness of the placenta and gestational age in healthy female dogs whose pregnancies had elapsed without maternal-fetal alterations. Eight Border Collie female dogs were selected, aged 3-6 (4.48 ± 0.89) and weighing 16-22 kg (19.06 ± 1.9 kg). Female dogs with gestational ages from 20 to 62 days were examined weekly using B-mode ultrasonography. Ultrasound measurements of the uteroplacental junction were organized into four distinct groups: GT1 (27-36 days of gestation), GT2 (37-46 days of gestation), GT3 (47-56 days of gestation) and GT4 (57-62 days of gestation). Based on multiple linear regression, a statistical model was proposed to predict the behaviour of the thickness of the uteroplacental junction (y) as a function of the length of gestation (x) in female dogs, where b0 is the intercept (linear coefficient) and bp is the slope of the predictors. The analysis relating GT, age and weight could predict placental thickness and resulted in a statistically significant model [F(1,28) = 153,736; p < .001; R2 = .846], but only that relating the length of pregnancy (ß = .92; t = 12.399; p < .001) predicted the thickness of the placenta according to the equation y = b0 + bp.x1 [(thickness in cm) = ß -0.3 + 0.019 × (gestation time in days)]. Only in GT4 was there no correlation between placentas within the same pregnancy (p > .05). Based on the close relationship between the development of the uteroplacental junction thickness during pregnancy and gestational age, it is possible to develop a new tool to complement gestational ultrasound evaluation in female dogs. This is important because it allows better placental evaluation in the search for significant alterations that could compromise maternal-fetal health.

Spectral Doppler ultrasound in the placental development of Mangalarga Marchador mares.

The aim of the study was to correlate the spectral index of the right and left uterine arteries with equine placental development in mares with advanced pregnancies. We examined 32 multiparous Mangalarga Marchador mares with gestation of 150-240 days. During pregnancy, the pulsatility index (PI) and resistance index (RI) of the uterine arteries were obtained using spectral Doppler ultrasonography, and the combined uteroplacental thickness was obtained monthly using B-mode ultrasonography. The combined uteroplacental thickness correlated with gestational time of up to 13 years of age, and the significant difference was observed from the sixth month onwards. The CUPT stayed within the ideal measurements for this breed and for this gestational period. There was no correlation of CUPT with PI, however a negative and significant correlation of the RI was observed. The resistance index differed significantly among age groups, and the RI of the left uterine artery tended to decrease in all age groups. Furthermore, only RI differed significantly between the medians of gestatinal age. The left PI dropped in older mares. Thus, there an increased blood perfusion in the uterine arteries of mares with advanced pregnancies and among different age categories during placental and fetal physiological development.

Spectral Doppler ultrasound in selecting an equine embryo receiver.

The aim of this study was to evaluate whether the RI and PI values would help in choosing the best embryo recipient, and observe whether CL vascularization would influence P4 production. During the breeding season 2018/2019, the study was conducted using 35 mares, which is used for reference to collect data for the project on the day of embryo transfer. The utilized mares were divided into five groups followed by the day after ovulation, with D0 being the day of ovulation. Therefore, the five groups are as follows: D4-mares that were on the 4th post-ovulation day; D5-mares that were on the 5th post-ovulation day; and doing so successively for D6, D7 and D8. On the day of embryo transfer, the CL of the mares that selected as recipients was evaluated by B-mode and power flow mode ultrasonography and the right and left dorsal branches of the uterine arteries by spectral Doppler ultrasonography. Blood samples were taken on the day of the embryo transfer for a dosage of P4 concentration by radioimmunoassay. No statistical difference was found between the variables when the mares were separated into pregnant and non-pregnant mares, or when they were separated by age groups. When the groups of mares were compared by the day of embryo transfer, the statistical difference was found between the groups D5 × D6 (p = .0053) and D6 × D8 (p = .0036) in RI variable. In PI variable, the statistical difference was found between the groups D4 × D8 (p = .049), D5 × D6 (p = .0446) and D6 × D8 (p = .0024). We conclude that the mares with RI measurement of uterine arteries near 1.0 are correlated to mares with high CL vascularization and elevated P4 concentration.

Pregnancy loss due to amnionitis in anglo-arabian mare-Case report.

The amnion is a layer of the foetal membrane that has mechanical protection function and allows expansion and growth. The diseases that affect amnion have rarely been reported in horses. Amnionitis and funiculitis have been implicated as components of abortions as observed in abortions caused by the mare reproductive loss syndrome. Here, we report an abortion at 240-day gestation of a 7-year-old Anglo-Arabian mare with a history of previous stillbirth. Blood samples from both mare and foetus were collected for serological testing. Fragments from the placenta were taken for macroscopic and histopathological examinations. The results of these tests ruled out leptospirosis and concluded that the cause of the abortion was non-infectious chronic amnionitis. Moreover, the decreased vascularization in the placenta was consistent with placental insufficiency. This case highlights the importance of monthly ultrasound monitoring in equine pregnancy in order to diagnose placental insufficiency. The study also confirmed the efficiency of the histopathological examination for the definitive diagnosis of placental inflammation and for the study of foetal vascularization to rule out placental insufficiency in equine reproduction.

Double ovarian tumour in the mare: Case report.

Ovarian tumours in mares represent 2.5% to 6% of the most frequent neoplasms found in the equine species, with a higher chance of benignity. This study aims to describe a case of two different tumours found in the same ovary of a mare that presented clinical signs of suppressed oestrous cycle during 5 years. After unilateral ovariectomy, the ovary was sent to the histopathology examination which determined a mixed tumour of granulosa cell and leiomyosarcoma. After treatment, the mare returned to oestrus and got pregnant in the next season.

Vascularização uterina de éguas prenhes de jumento e de garanhão monitoradas por ultrassonografia Doppler / Uterine vasculature of pregnant mares of donkey and stallion through the Doppler ultrasonography spectral mode

Este estudo teve como objetivo analisar e descrever os achados ultrassonográficos do útero de éguas gestantes de diferentes idades, de jumento e garanhão, utilizando a técnica de ultrassonografia Doppler Espectral, visando caracterizar os índices de resistência (RI) e pulsatilidade (PI) até 154 dias de gestação. Foram utilizadas 20 éguas em idade reprodutiva, sem raça definida. As avaliações foram realizadas nas artérias uterinas. Não foi constatada interação entre os valores de RI e PI obtidos nos cornos uterinos (que iniciaram ou não a gestação) com o tempo da gestação (P>0,05), desta forma os dados foram discutidos separadamente. Não foram encontradas diferenças entre as avaliações de RI e PI quando comparado os cornos que iniciaram ou não a gestação (P>0,05). Verificou-se efeito de tempo (P<0,05) sobre o PI, onde no D70 foi constatada a menor média quando comparado aos tempos D0, D7, D14 e D21. Não f oi encontrado efeito de tempo sobre o RI (P>0,05). As éguas gestantes de jumento apresentaram maior vascularização uterina no corno não gestante, que as éguas gestantes do garanhão. Com exceção do RI no lado não gravídico, foi verificado efeito de idade da fêmea sobre o lado da gestação (P<0,05), onde as éguas idosas, tanto no corno que iniciou a gestação e o contralateral, tiveram PI e RI mais altos, ou seja, menos vascularizados. Concluiu-se que a vascularização uterina não apresentou diferença entre os cornos uterinos. Há um aumento da vascularização uterina no 70º dia de gestação. Éguas gestantes de jumentos apresentaram maior vascularização uterina, quando comparada às éguas gestantes de garanhões. Éguas com idade acima de 15 anos apresentaram menor vascularização uterina, quando comparadas com idade inferior a 15 anos.(AU)

This study aimed to evaluate and describe the ultrasonographic findings of uterus of pregnant mares of different ages, mated by either ass or stallion, using the spectral Doppler ultrasonography, aiming to characterize the resistance (RI) and pulsatility (PI) Doppler indices up to 154 days of pregnancy. A total of 20 mares in reproductive age of non-defined breed were used. The evaluations were performed in uterine arteries. There was no interaction between RI and PI values obtained in uterine horns (that initiated or not the pregnancy) with time of pregnancy (P>0.05), thus, data were discussed separately. There were no differences between RI and PI evaluations when compared to the uterine horns that initiated or not the pregnancy (P>0.05). A time effect was observed (P<0.05) on PI, when D70 presented lower averages than D0, D7, D14 and D21. There was no time effect (P>0.05) on RI. Pregnant mares mated by asses presented higher uterine vascularization in non-pregnant horn than pregnant mares mated by stallions. With the exception of RI in non-pregnant horn, there was a female age effect on the side of pregnancy (P<0.05), where aged mares in both - pregnant and non-pregnant horns - showed higher PI and RI, so less vascularized. It is possible to conclude that the uterine vascularization did not present any difference between uterine horns. There is an increase in the uterine vascularization on the 70th day of pregnancy. Pregnant mares mated by assess presented higher uterine vascularization when compared to those mated by stallions. Mares aging over 15 years old presented lower uterine vascularization, when compared to those younger.(AU)

Transrectal ultrasonography for measuring of combined utero-placental thickness in pregnant Mangalarga Marchador mares.

This study aimed to measure the physiological changes in the combined utero-placental thickness (CUPT) during the course of normal pregnancy in Mangalarga Marchador mares. Transrectal B-mode ultrasonography was used to measure CUPT in 42 pregnant mares with a mean age, 8.7 (±3.5 years). CUPT was measured every month from 150 days of gestation until delivery. CUPT was expressed as an average of three measurements of the distance (mm) between the middle part of the uterine artery and the allantoic fluid. A General Linear Model was used to evaluate the major effects of the chronological age and stage of gestation on CUPT in mares. The coefficient of determination (R2) was 0.571 (P < 0.001). There was no correlation between CUPT and the chronological age of the mares, however, there was a positive correlation between CUPT and the stage of gestation, which an accounted for 29.6% of the observed variation. CUPT significantly increased during the gestational period from 210 to 240 days and 270-300 days. These results showed CUPT increased as pregnancy advanced in the Mangalarga Marchador mares. In conclusion these effects of the stage of pregnancy on the increase in CUPT showed a physiological parameters of ultrasonography evaluation of the placenta in Mangalarga Marchador mares.

The role of leptospirosis in reproductive disorders in horses.

Leptospirosis is a zoonotic disease of global importance and has a worldwide distribution. This infection displays clear seasonal nature in some regions of the tropics, where the rainy season is marked by high temperatures. Household and wild animals carry leptospires and contribute to their dissemination in nature. Transmission mainly occurs by contact with water contaminated with the urine of infected animals, and consequently, it is quite widespread especially in times of rain, since many areas are subject to flooding and have poor sanitation. Serological tests demonstrate that Leptospira sp. infection in horses occurs worldwide and that the predominant serovar may vary depending on the region or infection sources. Besides systemic and ocular manifestations, leptospirosis in horses has been recognized as an important disease of the reproductive system, since it leads to the birth of weak foals, stillbirths or neonatal mortality, and mainly to abortion, usually after the sixth month of pregnancy. In this context, this review aims to gather and discuss information about the role of leptospirosis in reproductive disorders in horses.

Fatal diarrhea caused by multidrug resistant Pseudomonas aeruginosa in a foal from Rio de Janeiro, Brazil

The present study evaluated the susceptibility pattern of one Pseudomonas aeruginosa isolate obtained from a deceased foal following an acute case of diarrhea. The isolate was identified by reference methods and tested with a panel of 27 antimicrobial agents. Pseudomonas aeruginosa was confirmed in pure culture and the isolate demonstrated resistance to all tested antimicrobials. Since it was a unique case in this herd, we suggest that contamination did not happen by horizontal transmission. The multidrug resistance was unexpected, associated to the virulence of the isolate, that killed the foal in five days, despite treatment.

Pulmonary hemorrhage in horses seropositive to leptospirosis / Hemorragia pulmonar em cavalos soropositivos para leptospirose

The aim of this study was to verify the occurrence and severity of pulmonary hemorrhage (PH) in horses seropositive or not to leptospirosis. A total of 84 training horses were tested for anti-Leptospira antibodies and submitted to endoscopy of the upper airways 30-60 minutes after exercise. Forty-nine (46.4 percent) horses were seropositive (titer>100) to serovar Copenhageni. Seventeen horses (20.2 percent) presented PH in different grades, significantly more commonly observed in seropositives (34.7 percent) than seronegatives (8.6 percent) (p<0.05), and also more severe in the first. Additionally, a seropositive horse is 4.26 times more likely (OR) to present PH than a seronegative one. Fifteen days after specific antibiotic treatment for leptospirosis a significant improvement in grade of hemorrhage was observed. Therefore it is suggested that leptospirosis may potentiate the severity of PH and that specific antibiotic treatment directed towards leptospirosis may help to control the disease.

O objetivo foi estudar a ocorrência e severidade de hemorragia pulmonar (HP) em cavalos soropositivos ou não à leptospirose. Um total de 84 cavalos em treinamento foi testado para anticorpos anti-Leptospira e submetidos à endoscopia das vias aéreas superiores de 30-60 minutos após exercício. Quarenta e nove (46,4 por cento) animais foram soropositivos (títulos>100) para o serovar Copenhageni. Dezessete cavalos (20,2 por cento) apresentaram HP, significativamente mais observada em soropositivos (34,7 por cento) do que em soronegativos (8,6 por cento) (p<0,05) e também mais grave nos primeiros. Adicionalmente, um cavalo soropositivo tem 4,26 mais chances (OR) de apresentar PH do que um soronegativo. Quinze dias após o tratamento com antibiótico específico para leptospirose uma melhoria significativa no grau de hemorragia foi observada. Portanto, sugere-se que a leptospirose pode potencializar a severidade da HP e que o tratamento com antibióticos específicos recomendados para leptospirose pode ajudar a controlá-la.