Effect of pregnancy and correlation of weight and heart rate with electrocardiographic parameters in the American Miniature Horse / Efeito da prenhez e correlação do peso e frequência cardíaca com os parâmetros eletrocardiográficos de equinos Mini-horse

There are studies on electrocardiogram (ECG) in several breeds of horses, which highlights the growing importance of cardiology in this species. But few authors have addressed the influence of pregnancy on the cardiac physiology of the mare, and specifically, there are no studies on the Mini-horse breed, as well as no correlation of body weight (BW) and heart rate (HR) with electrocardiographic parameters in this breed. The aims of this study were to determine the effects of pregnancy on ECG parameters and to examine the relationships between these variables and body weight (BW) and heart rate (HR). A total of 203 animals were used, including 143 females (66 pregnant) and 60 males. Electrocardiographic examinations were performed by computerized electrocardiogram (TEB), and the parameters were evaluated in six leads in the frontal plane (Lead I, II, III, aVR, aVL and aVF) and base-apex (BA). BW was inversely proportional to HR, which in turn showed an inverse relationship with the duration of the P-wave and the PR and QT intervals. The P-wave amplitude (lead II) was higher in pregnant animals than in non-pregnant animals. The effect of reproductive status should be monitored by ECG throughout the entire gestational period. The 66 pregnant mares in this study were examined during the first third of their pregnancies, thus, few differences were observed between pregnant and non-pregnant animals.(AU)

Existem estudos sobre eletrocardiograma (ECG) em diversas raças de equinos, o que ressalta a crescente relevância da cardiologia nessa espécie. Porém, poucos autores abordaram a influência da gestação na fisiologia cardíaca da égua, e, especificamente, não há trabalhos sobre a raça Mini-horse, assim como não há correlação do peso vivo (PV) e frequência cardíaca (FC) com os parâmetros eletrocardiográficos nessa raça. O objetivo deste estudo foi estudar a influência da prenhez sobre os parâmetros eletrocardiográficos, além de verificar a correlação do PV e FC com essas variáveis. Utilizaram-se 203 animais dessa raça, hígidos, sendo 143 fêmeas (66 prenhes) e 60 machos. Os exames eletrocardiográficos foram realizados por eletrocardiograma computadorizado (TEB), e os parâmetros foram avaliados em seis derivações do plano frontal (I, II, III, aVR, aVL e aVF) e base-ápice. O PV foi inversamente proporcional à FC, que também mostrou relação inversa com a duração da onda P e os intervalos PR e QT. Na derivação II, a amplitude da onda P foi maior nos animais prenhes do que vazios. No entanto, sugere-se que a influência do estado reprodutivo seja estudada de forma progressiva pelo acompanhamento de todo o período gestacional, visto que as 66 éguas estudadas se apresentavam no terço inicial da prenhez, portanto poucas diferenças foram observadas entre animais prenhes e vazios.(AU)

Análise da variabilidade da frequência cardíaca em cordeiros da raça Bergamácia, do nascimento aos 35 dias de idade / Analysis of heart rate variability in Bergamasca newborn lambs from birth at 35th days of age

A atividade do sistema nervoso autônomo sobre o coração pode ser verificada pela variabilidade da frequência cardíaca (VFC), método que quantifica e assim infere sobre a modulação autonômica cardíaca, refletindo o funcionamento do sistema nervoso autônomo. Durante o período neonatal, diferenças significativas no que se refere à maturação autonômica são descritas em diversas espécies. Embora a espécie ovina venha sendo utilizada como modelo experimental em diversos protocolos em neonatologia e cardiologia em humanos, estudos descritivos sobre a VFC utilizando animais saudáveis e não sedados são escassos na literatura. O objetivo do estudo foi descrever a VFC em cordeiros da raça Bergamácia durante os primeiros 35 dias de idade. Foram realizados exames eletrocardiográficos em 20 cordeiros da raça Bergamácia a partir do nascimento e semanalmente até o 35° dia de idade. A VFC foi analisada pelo intervalo RR normal (batimentos sinusais), pela frequência cardíaca, pelo índice de tônus vasovagal (iTVV), pela raiz quadrada da média do quadrado das diferenças entre intervalos RR normais adjacentes (RMSSD) e pela raiz quadrada da somatória do quadrado das diferenças dos valores individuais em relação ao valor médio, dividido pelo número de iR-R em 90 segundos - VFC global (RMSM). Todos os parâmetros se alteraram ao longo das semanas. A frequência cardíaca média elevou-se entre o nascimento e os primeiros sete dias de idade, com decréscimo nas quatro semanas subsequentes, sendo o menor valor encontrado aos 35 dias de idade (145,63±37,80bpm). Entre 21, 28 e 35 dias de idade, o iTVV elevou-se significativamente, o RMSM a partir do 28º dia, e, aos 35 dias, o RMSSD, reflexo da ativação parassimpática, exibiu diferenças em relação aos momentos subsequentes. O início da predominância parassimpática, refletida nos índices da VFC, particularmente o iTVV, ocorre aos 21 dias de idade. A partir dos 35 dias de idade, os índices RMSM e RMSSD podem ser utilizados como marcadores fidedignos das mudanças nos efeitos simpático e parassimpático sobre o coração de cordeiros.(AU)

Autonomic nervous system activity can be checked by heart rate variability (HRV), method that quantifies and thus infers on cardiac autonomic modulation, reflecting the functioning of the autonomic nervous system. During the neonatal period significant differences as regards the autonomic maturation, are described in various species. Although the sheep come being used as experimental model of several protocols in neonatology and cardiology in humans, descriptive studies about the VFC using healthy animals and not sedated are scarce in the literature. The objective of this study was to describe the HRV in the Bergamasca race lambs during the first 35 days of age. Electrocardiographic examinations were performed in 20 lambs of the Bergamasca race from birth, in the7th, 14th, 21st, 28th, and 35th days of age. The HRV was analyzed by normal RR interval (sinus rate), heart rate, index of vagal tone, and the cardiovascular manifestations (square root of the average of the square of the differences between normal RR intervals adjacent). All parameters have changed over the weeks. The average heart rate increased between the birth and the first seven days of age, with decrease in the subsequent four weeks, being the smallest value found at 35 days of age (145.63±37.80bpm). Between 21, 28 and 35 days of age, the iTVV increased significantly, the RMSM from the 28 day, and 35 days, the cardiovascular manifestations, reflex parasympathetic activation, exhibited differences in relation to subsequent times. The beginning of parasympathetic dominance, reflected in the HRV indices, particularly the iTVV, occurs at 21 days of age. From the 35 days of age, the RMSM indices and RMSSD can be used as reliable markers of change in sympathetic and parasympathetic effect on the heart of lambs.(AU)

Análise da variabilidade da frequência cardíaca em cordeiros da raça Bergamácia, do nascimento aos 35 dias de idade / Analysis of heart rate variability in Bergamasca newborn lambs from birth at 35th days of age

Autonomic nervous system activity can be checked by heart rate variability (HRV), method that quantifies and thus infers on cardiac autonomic modulation, reflecting the functioning of the autonomic nervous system. During the neonatal period significant differences as regards the autonomic maturation, are described in various species. Although the sheep come being used as experimental model of several protocols in neonatology and cardiology in humans, descriptive studies about the VFC using healthy animals and not sedated are scarce in the literature. The objective of this study was to describe the HRV in the Bergamasca race lambs during the first 35 days of age. Electrocardiographic examinations were performed in 20 lambs of the Bergamasca race from birth, in the7th, 14th, 21st, 28th, and 35th days of age. The HRV was analyzed by normal RR interval (sinus rate), heart rate, index of vagal tone, and the cardiovascular manifestations (square root of the average of the square of the differences between normal RR intervals adjacent). All parameters have changed over the weeks. The average heart rate increased between the birth and the first seven days of age, with decrease in the subsequent four weeks, being the smallest value found at 35 days of age (145.63±37.80bpm). Between 21, 28 and 35 days of age, the iTVV increased significantly, the RMSM from the 28 day, and 35 days, the cardiovascular manifestations, reflex parasympathetic activation, exhibited differences in relation to subsequent times. The beginning of parasympathetic dominance, reflected in the HRV indices, particularly the iTVV, occurs at 21 days of age. From the 35 days of age, the RMSM indices and RMSSD can be used as reliable markers of change in sympathetic and parasympathetic effect on the heart of lambs.(AU)

A atividade do sistema nervoso autônomo sobre o coração pode ser verificada pela variabilidade da frequência cardíaca (VFC), método que quantifica e assim infere sobre a modulação autonômica cardíaca, refletindo o funcionamento do sistema nervoso autônomo. Durante o período neonatal, diferenças significativas no que se refere à maturação autonômica são descritas em diversas espécies. Embora a espécie ovina venha sendo utilizada como modelo experimental em diversos protocolos em neonatologia e cardiologia em humanos, estudos descritivos sobre a VFC utilizando animais saudáveis e não sedados são escassos na literatura. O objetivo do estudo foi descrever a VFC em cordeiros da raça Bergamácia durante os primeiros 35 dias de idade. Foram realizados exames eletrocardiográficos em 20 cordeiros da raça Bergamácia a partir do nascimento e semanalmente até o 35° dia de idade. A VFC foi analisada pelo intervalo RR normal (batimentos sinusais), pela frequência cardíaca, pelo índice de tônus vasovagal (iTVV), pela raiz quadrada da média do quadrado das diferenças entre intervalos RR normais adjacentes (RMSSD) e pela raiz quadrada da somatória do quadrado das diferenças dos valores individuais em relação ao valor médio, dividido pelo número de iR-R em 90 segundos - VFC global (RMSM). Todos os parâmetros se alteraram ao longo das semanas. A frequência cardíaca média elevou-se entre o nascimento e os primeiros sete dias de idade, com decréscimo nas quatro semanas subsequentes, sendo o menor valor encontrado aos 35 dias de idade (145,63±37,80bpm). Entre 21, 28 e 35 dias de idade, o iTVV elevou-se significativamente, o RMSM a partir do 28º dia, e, aos 35 dias, o RMSSD, reflexo da ativação parassimpática, exibiu diferenças em relação aos momentos subsequentes. O início da predominância parassimpática, refletida nos índices da VFC, particularmente o iTVV, ocorre aos 21 dias de idade. A partir dos 35 dias de idade, os índices RMSM e RMSSD podem ser utilizados como marcadores fidedignos das mudanças nos efeitos simpático e parassimpático sobre o coração de cordeiros.(AU)

Effect of pregnancy and correlation of weight and heart rate with electrocardiographic parameters in the American Miniature Horse / Efeito da prenhez e correlação do peso e frequência cardíaca com os parâmetros eletrocardiográficos de equinos Mini-horse

There are studies on electrocardiogram (ECG) in several breeds of horses, which highlights the growing importance of cardiology in this species. But few authors have addressed the influence of pregnancy on the cardiac physiology of the mare, and specifically, there are no studies on the Mini-horse breed, as well as no correlation of body weight (BW) and heart rate (HR) with electrocardiographic parameters in this breed. The aims of this study were to determine the effects of pregnancy on ECG parameters and to examine the relationships between these variables and body weight (BW) and heart rate (HR). A total of 203 animals were used, including 143 females (66 pregnant) and 60 males. Electrocardiographic examinations were performed by computerized electrocardiogram (TEB), and the parameters were evaluated in six leads in the frontal plane (Lead I, II, III, aVR, aVL and aVF) and base-apex (BA). BW was inversely proportional to HR, which in turn showed an inverse relationship with the duration of the P-wave and the PR and QT intervals. The P-wave amplitude (lead II) was higher in pregnant animals than in non-pregnant animals. The effect of reproductive status should be monitored by ECG throughout the entire gestational period. The 66 pregnant mares in this study were examined during the first third of their pregnancies, thus, few differences were observed between pregnant and non-pregnant animals.(AU)

Existem estudos sobre eletrocardiograma (ECG) em diversas raças de equinos, o que ressalta a crescente relevância da cardiologia nessa espécie. Porém, poucos autores abordaram a influência da gestação na fisiologia cardíaca da égua, e, especificamente, não há trabalhos sobre a raça Mini-horse, assim como não há correlação do peso vivo (PV) e frequência cardíaca (FC) com os parâmetros eletrocardiográficos nessa raça. O objetivo deste estudo foi estudar a influência da prenhez sobre os parâmetros eletrocardiográficos, além de verificar a correlação do PV e FC com essas variáveis. Utilizaram-se 203 animais dessa raça, hígidos, sendo 143 fêmeas (66 prenhes) e 60 machos. Os exames eletrocardiográficos foram realizados por eletrocardiograma computadorizado (TEB), e os parâmetros foram avaliados em seis derivações do plano frontal (I, II, III, aVR, aVL e aVF) e base-ápice. O PV foi inversamente proporcional à FC, que também mostrou relação inversa com a duração da onda P e os intervalos PR e QT. Na derivação II, a amplitude da onda P foi maior nos animais prenhes do que vazios. No entanto, sugere-se que a influência do estado reprodutivo seja estudada de forma progressiva pelo acompanhamento de todo o período gestacional, visto que as 66 éguas estudadas se apresentavam no terço inicial da prenhez, portanto poucas diferenças foram observadas entre animais prenhes e vazios.(AU)

Concentração de lactato sérico em ovelhas e cordeiros mestiços (1/2 Suffolk) nascidos em eutocia / Lactate blood levels in sheep and newborn lambs (1/2 suffolk) in normal delivery

O objetivo do estudo foi avaliar a concentração de lactato sanguíneo venoso em ovelhas e em cordeiros neonatos imediatamente após o parto eutócico. Foram utilizadas 14 ovelhas, sendo nove da raça Suffolk e quatro mestiças e 20 cordeiros neonatos sadios (machos e fêmeas). O efeito do sexo, da raça e do número de cordeiros por parto foi investigado, bem como a possível correlação entre a concentração de lactato materno e neonatal. Não houve diferença entre machos e fêmeas, em relação à raça (Suffolk e mestiços), contudo a concentração de lactato foi mais elevada em cordeiros gêmeos ou trigêmeos quando comparado a cordeiros uníparos. Houve correlação positiva entre a concentração materna e a neonatal, sendo que quanto maior a concentração de lactato materno, maior a concentração no cordeiro imediatamente após o parto eutócico. Os resultados do presente estudo fornecem um subsídio por meio do qual se podem comparar os níveis de lactato sanguíneo em cordeiros em estado crítico.(AU)

The aim of this study was to evaluate the venous blood lactate concentration in sheep and newborn lambs immediately after normal delivery. We used 14 ewes, nine and four Suffolk crossbred lambs and 20 healthy newborns (males and females). The effect of gender, race and number of lambs per birth was investigated, as well as the possible correlation between the concentration of maternal and newborn lactate. There was no difference between males and females or in relation to race (and Suffolk crossbred); however the concentration of lactate was higher in twin or triplet lambs when compared to single lambs. There was a positive correlation between the maternal and newborn concentration and the higher the concentration of lactate, the greater the concentration in the lamb immediately after normal delivery. The results of this study provide a base from which to compare the blood lactate levels in lambs in critical condition.(AU)

Improving postcryopreservation survival capacity: an embryo-focused approach

The major challenge for a greater dissemination of in vitro produced (IVP) bovine embryos is to improve embryonic survival after cryoprese rvation. The involvement of embryo niclipids on this issue is well documented. However, it has been recognized that not only the amount of lipids that affects embryo cryotolerance, but the embryo survival capacity after cryopreservation is a rather multifactorial event. In this review, some strategies to improve embryonic lipid composition and postcryo preservation survival by modifying the embryos themselves to make them more cryopreservable are overviewed The ue of sedefined and defined serum free cul ture media, the addition of some chemicals in the culture media to modify embryo lipid composition, and the modulation of embryo cell membrane fluidity by cholesterol or unsaturated fatty acids added to the culture media and oocyte/embryo donor nutritional management with a diet enriched in polyunsaturated fatty acids, were described as alternatives for the improvement of IVP embryo survival after cryopreservation.

Improving postcryopreservation survival capacity: an embryo-focused approach

The major challenge for a greater dissemination of in vitro produced (IVP) bovine embryos is to improve embryonic survival after cryoprese rvation. The involvement of embryo niclipids on this issue is well documented. However, it has been recognized that not only the amount of lipids that affects embryo cryotolerance, but the embryo survival capacity after cryopreservation is a rather multifactorial event. In this review, some strategies to improve embryonic lipid composition and postcryo preservation survival by modifying the embryos themselves to make them more cryopreservable are overviewed The ue of sedefined and defined serum free cul ture media, the addition of some chemicals in the culture media to modify embryo lipid composition, and the modulation of embryo cell membrane fluidity by cholesterol or unsaturated fatty acids added to the culture media and oocyte/embryo donor nutritional management with a diet enriched in polyunsaturated fatty acids, were described as alternatives for the improvement of IVP embryo survival after cryopreservation.(AU)

Estudo da pressão arterial pelo método indireto oscilométrico (petmap®) em cães domésticos não anestesiados / Study of blood pressure by the indirect oscillometric method (petmap®) in domestic unanesthetized dogs

O estudo das pressões arteriais sistólica, média, diastólica e da frequência cardíaca, pelo método indireto oscilométrico (petmap®), foi realizado em 150 cães atendidos pelo Serviço de Clínica Médica de Pequenos Animais da FMVZ - Unesp/Botucatu. Investigou-se a influência de fatores como presença do proprietário, estado de saúde, diagnóstico de doença renal, raça, idade, sexo, decúbito, contenção, fluidoterapia, condição corpórea, temperamento, atividade física, dieta e atitude associados ou não à elevação da pressão arterial. Dos 150 cães, 34% encontravam-se sob a categoria de risco mínimo para o desenvolvimento de lesões hipertensivas, 14,6% com hipertensão branda, 22,6% com hipertensão moderada e 28,66%, com hipertensão grave. Houve influência, dos fatores analisados, na elevação da pressão arterial de acordo com a categoria de risco.(AU)

The study of systolic, mean, diastolic and heart rate by the oscillometric indirect method (PetMapTM) was performed in 150 dogs attended by the Small Animal Service of Medicine of FMVZ - Unesp/Botucatu. The influence of factors such as presence of the owner, health status, diagnosis of kidney disease, race, age, sex, recumbency, containment, fluid, body condition, temperament, physical activity, diet and attitude associated or not with elevated blood pressure was investigated. Of the 150 dogs, 34% were under the category of minimal risk for the development of hypertensive lesions, 14.6% with mild hypertension, 22.6% with moderate hypertension and 28.66% with severe hypertension. The analyzed factors influenced the elevation of blood pressure according to risk category.(AU)

Preservation of wild feline semen by freeze-drying: experimental model

According to the Convention on International Trade in Endangered Species, 36 wild feline species are threatened by extinction or severely endangered, and to save them is the target of several conservation programs. This study aimed to assess the viability of the freeze-drying technique for domestic cat sperm cells, with the ultimate goal of transferring this technology to the wild feline species. The do mestic cat is an excellent experimental model for wild felids. It is in this scenario that the freeze-drying process (low-temperature vacuum dehydration) of sperm cells shows its value in preserving male cats’ germplasm. Results from membrane and DNA integrity analysis are promising and validates the use of frozen-dried sperm samples in intracytoplasmic sperm injections (ICSIs). Further studies are still necessary to evaluate the ICSI embryo production using domestic cat frozen-dried sperm and the possibility of using such technology with wild felines.

Preservation of wild feline semen by freeze-drying: experimental model

According to the Convention on International Trade in Endangered Species, 36 wild feline species are threatened by extinction or severely endangered, and to save them is the target of several conservation programs. This study aimed to assess the viability of the freeze-drying technique for domestic cat sperm cells, with the ultimate goal of transferring this technology to the wild feline species. The do mestic cat is an excellent experimental model for wild felids. It is in this scenario that the freeze-drying process (low-temperature vacuum dehydration) of sperm cells shows its value in preserving male cats germplasm. Results from membrane and DNA integrity analysis are promising and validates the use of frozen-dried sperm samples in intracytoplasmic sperm injections (ICSIs). Further studies are still necessary to evaluate the ICSI embryo production using domestic cat frozen-dried sperm and the possibility of using such technology with wild felines.(AU)

Concentração de lactato e glicemia em cadelas e neonatos nascidos de cesariana / Lactato concentration in bitch and canine neonates born through cesarean section

Avaliaram-se a concentração de lactato e a glicemia em sete cadelas em trabalho de parto submetidas à cesariana e em seus respectivos neonatos. O lactato materno foi mensurado utilizando-se medidor portátil e pelo método enzimático colorimétrico. Nos neonatos avaliou-se também o peso ao nascimento. Os valores de lactato materno e neonatal foram estatisticamente diferentes, sendo mais elevado nos neonatos. Ao nascimento, as cadelas e os neonatos encontravam-se normoglicêmicos, e não se observou correlação entre a glicemia de ambos. Os valores de lactato obtidos pelo o analisador portátil (3,5±0,6mmol/L) foram mais altos do que os obtidos pelo método enzimático colorimétrico (1,6±0,6mmol/L). Observou-se correlação significativa entre o peso do neonato e a concentração de lactato, isto é, os filhotes de menor peso apresentaram maior concentração de lactato.(AU)

This work evaluated the concentration of lactate and blood glucose in seven bitches in labor subject to caesarean section and in their newborns. The lactate concentration was measured using a portable analyzer and enzymatic colorimetric method. In neonates, the birth weight was evaluated. The maternal and neonatal lactate values were statistically different, being higher in newborns. At birth, the bitches and the newborns had normal glucose status, and no correlation was observed between blood glucose in either. The lactate concentration obtained by the portable analyzer (3.5±0.6mmol/L) was higher than that obtained with the enzymatic colorimetric method (1.6±0.6mmol/L). There was significant correlation between the neonate weight and lactate concentration and in puppies with lighter weight there was a higher concentration of lactate.(AU)

In vitro production of bovine embryos using Sigma antioxidant supplement®, tocopherol and L-ascorbic acid

This study tested the effect of Sigma antioxidant supplement®, α-tocopherol (vitamin E) and L-ascorbic acid (vitamin C) in the culture medium of bovine embryos. In experiment 1, in vitro produced bovine zygotes were cultured in Human Tubal Fluid (HTF): Eagles Basic Medium (BME) with: Group 1 50 µm vitamin C; Group 2 200 µm vitamin E; Group 3 25 µm vitamin C and 100 µm vitamin E; Group 4 1 µl/ml Sigma antioxidant supplement®; and the Control group HTF:BME only. In experiment 2, embryos were cultured in high or low oxygen tension with HTF:BME + Sigma antioxidant supplement® or in HTF:BME alone (Control). The data were analyzed using ANOVA followed by Tukeys test. The results of experiment 1 showed a negative effect (P < 0.05) of vitamin E on blastocyst production in Group 2 (19.7 ± 0.1%). This effect was reduced in Group 3 by the addition of vitamin C (26.1 ± 0.2%). The use of vitamin C alone (34.9 ± 0.3%) or the Sigma antioxidant supplement® (33.3 ± 0.7%) did not increase (P > 0.05) the number of blastocysts produced compared with the control group (30.1 ± 0.5%). During experiment 2, there was no effect (P > 0.05) from the culture medium or the O2 concentrations used, indicating that the reduction of the O2 concentration did not improve blastocyst production.(AU)

In vitro production of bovine embryos using Sigma antioxidant supplement®, tocopherol and L-ascorbic acid

This study tested the effect of Sigma antioxidant supplement®, α-tocopherol (vitamin E) and L-ascorbic acid (vitamin C) in the culture medium of bovine embryos. In experiment 1, in vitro produced bovine zygotes were cultured in Human Tubal Fluid (HTF): Eagle’s Basic Medium (BME) with: Group 1 – 50 µm vitamin C; Group 2 – 200 µm vitamin E; Group 3 – 25 µm vitamin C and 100 µm vitamin E; Group 4 – 1 µl/ml Sigma antioxidant supplement®; and the Control group – HTF:BME only. In experiment 2, embryos were cultured in high or low oxygen tension with HTF:BME + Sigma antioxidant supplement® or in HTF:BME alone (Control). The data were analyzed using ANOVA followed by Tukey’s test. The results of experiment 1 showed a negative effect (P 0.05) the number of blastocysts produced compared with the control group (30.1 ± 0.5%). During experiment 2, there was no effect (P > 0.05) from the culture medium or the O2 concentrations used, indicating that the reduction of the O2 concentration did not improve blastocyst production.