Cardiorespiratory/sedative effects of a peptide identified in crotalic venom compared to acepromazine and xylazine in horses / Efeitos cardiorrespiratórios/sedativos de um peptídeo identificado no veneno crotálico comparado à acepromazina e à xilazina em equinos

The purpose of this study was to investigate whether intravenous crotalphine produces significant sedation, as well as physiological changes, in healthy standing horses. Six mares, aged 8 years and weighing 415kg underwent three different treatments in a crossover design: TA (acepromazine: 50µg.kg-1), TC (crotalphine: 0.01µg.kg-1) and TX (xylazine: 1000µg.kg-1), intravenously. At various time points over 60 minutes, physiologic variables were recorded: heart rate, respiratory rate, and rectal temperature. The head height from the ground (HHG) was evaluated in centimeters. Data were analyzed using ANOVA followed by Dunnett's test or Friedman followed by Dunn's test, under 5% significance. Heart rate decreased significantly at M5 and M10 compared with Mb in TX (28±7, 26±6 and 40±8 beats/minute-1, respectively; p=0.0004). Respiratory rate and rectal temperature did not differ among groups or time points. The HHG significantly decreased in all groups compared with Mb at various time points (p<0.0001). In conclusion, crotalphine did not produce reliable and durable sedation in healthy standing mares and did not influence cardiorespiratory variables in a clinically relevant manner.

O objetivo deste estudo foi investigar se a administração de crotalfina intravenosa produz sedação significativa e alterações fisiológicas em equinos saudáveis. Seis éguas, idade média de oito anos e peso médio de 415kg, foram submetidas a três tratamentos distintos: TA (acepromazina: 50µg/kg), TC (crotalfina: 0,01µg/kg) e TX xilazina: 1000µg/kg), por via intravenosa. Em vários momentos, ao de longo de 60 minutos, as variáveis fisiológicas registradas foram frequência cardíaca, frequência respiratória e temperatura retal. A altura de cabeça ao solo (ACS) foi avaliada em centímetros. Os dados foram analisados pela ANOVA, seguida pelo teste de Dunnett ou de Friedman e, depois, pelo teste de Dunn, sob 5% de significância. A frequência cardíaca diminuiu significativamente em M5 e M10 em comparação com Mb em TX (28±7, 26±6 e 40±8 bpm, respectivamente; P=0,0004). A frequência respiratória e a temperatura retal não diferiram entre os grupos ou os pontos de tempo. O HHG diminuiu significativamente em todos os grupos em comparação com Mb em vários momentos (P <0,0001). Em conclusão, a crotalfina não produziu sedação confiável e durável em éguas saudáveis e não influenciou as variáveis cardiorrespiratórias de maneira clinicamente relevante.

Protocolo de sedação visando a castração química em cães / Sedation protocol aiming to chemical castration in dogs

A castração química é utilizada para castrar cães machos a um custo mais baixo que o procedimento cirúrgico, que é o método mais aplicado para castrar cães e gatos. A castração química é um procedimento mais simples que a castração cirúrgica e pode ser realizada a nível ambulatorial, sem necessidade de anestesia geral. Entretanto, devido ao estresse pela manipulação e ao desconforto produzido pela injeção de uma substância no interior dos testículos, faz-se necessária uma sedação para que a castração química seja efetuada de um modo que proporcione o bem-estar do animal. Assim, este artigo tem como objetivo propor um protocolo inovador para sedação de cães submetidos à castração química. Para isso, foram utilizados 12 cães submetidos à administração de xilazina em subdose no acuponto yin tang. Após o estabelecimento da sedação, os cães foram castrados quimicamente. O protocolo proposto permitiu que a castração química fosse realizada com conforto para o paciente e para a equipe de médicos veterinários. Desta forma, concluiu-se que o protocolo de sedação é seguro e pode ser empregado em cães para procedimentos não invasivos, como exames, coleta de material e outros processos ou técnicas semelhantes.

Chemical castration is used to spay male dogs at a lower cost than the surgical procedure, which is the most applied method to spay dogs and cats. Chemical castration is a simpler procedure than surgical castration and can be performed on an outpatient basis, without the need for general anesthesia. However, due to the stress caused by manipulation and the discomfort produced by the injection of a substance into the testicles, sedation is necessary so that chemical castration is to be carried out in a way that provides the animal's welfare. Thus, this article aims to propose an innovative protocol for sedation of dogs submitted to chemical castration. For this purpose, twelve dogs submitted to the administration of xylazine in subdosis in the yin-tang acupoint were used. After the establishment of sedation, the dogs were chemically neutered. The proposed protocol allowed chemical castration to be performed with comfort for the patient and the team of veterinarians. Therefore, it is concluded that the sedation protocol is safe and can be used in dogs for non-invasive procedures such as exams, material collection, and other similar processes or techniques.

Oxygen supply as a refining technique for injectable anesthesia in laboratory rats

Well-controlled anesthesia is critical to reducing potential surgical complications and ensuring safe and successful procedures. Respiratory depression, inducing hypoxia, and hypercapnia are adverse effects of injectable anesthesia in laboratory rats. This study aimed to determine the effect of oxygen supply in laboratory rats anesthetized with the combination of ketamine (K) and xylazine (X) plus acepromazine (A) or methadone (Me). The results showed that oxygenation allowed adequate levels of SO2 and paO2, avoiding hypoxemia. However, all anesthetized rats showed respiratory acidosis with low pH and high paCO2 levels, which was not reversed after oxygen administration. The acidosis could be related to hypoventilation due to respiratory depression induced by the XKMe association, as well as absorption atelectasis with the CO2 accumulation during anesthesia. Despite respiratory acidosis, oxygen administration was beneficial for anesthetized rats preventing hypoxemia. This makes it possible to prevent all the metabolic alterations that cause cell death by hypoxia, improving the well-being of anesthetized rats, as well as the quality of the results obtained.

Establishing an anesthetic protocol for refinement of intracerebral inoculation procedure

Mouse inoculation test (MIT) is a technique widely used for rabies diagnosis and must be liable to refinement due to animal welfare. The present study aims to compare five different anesthetic associations to stablish a protocol to improve the MIT procedure suitable for animal welfare and safe for a routine of viral isolation in newly weaned mice (3 weeks of age). 80 Swiss-Webster mice (Mus musculus) - 40 females and 40 males, 3-week-old, weight ranging from 11 to 14 grams ­ were used to conduct all procedures. Five anesthetic associations were tested: KX (Ketamine 100 mg/kg and Xylazine 10 mg/kg), KXA (Ketamine 80 mg/kg, Xylazine 5 mg/kg, and Acepromazine 1 mg/kg), KXT (Ketamine 80 mg/kg, Xylazine 5 mg/kg, and Tramadol 5 mg/kg), KXAT (Ketamine 100 mg/kg, Xylazine 10 mg/kg, Acepromazine 2 mg/kg and Tramadol 5 mg/kg) and ATI (Acepromazine 1 mg/kg + Tramadol 5 mg/kg + Isoflurane 5% - 0.5 L/min for induction and 2.5% - 0.5L/min for maintenance). Injectable anesthesia was administered intraperitoneally. We monitored the respiratory rate and body temperature. Response to anesthesia was evaluated according to the induction, surgical anesthesia, and recovery periods. The KXAT and ATI protocols induced surgical anesthesia, with the ATI protocol being the most appropriate and safe to perform the MIT procedure with 100% efficiency, absence of mortality, and rapid recovery of respiratory rate and temperature in the period after the procedure.

A new anesthetic protocol to medullary nerve roots access in rats

ABSTRACT Purpose: To describe a new anesthetic protocol medullary and nerve roots access and in Rattus norvegicus. Methods: Seventy female Wistar rats (n=70) were used. The animals were randomly divided into two laminectomy groups: cervical (n=40) and thoracic (n=30). In cervical group, a right posterior hemilaminectomy was performed to access the nerve roots. In thoracic group, a laminectomy of the eighth thoracic vertebra was accomplished. Thirty-five rats (20 cervical and 15 thoracic) were submitted to old anesthetic protocol (ketamine 70 mg/kg plus xylazine 10 mg/kg); and the 35 other animals (20 cervical and 15 thoracic) were submitted to a new anesthetic protocol (ketamine 60 mg/kg,xylazine 8 mg/kg and fentanyl 0.03 mg/kg). Results: The time to complete induction was 4.15 ±1.20 minin ketamine, xylazine and fentanyl group, and it was 4.09 ±1.47 min in the ketamine and xylazine group. There was no correlation in the time required to perform the cervical laminectomy in the old anesthetic protocol. In all groups, the animals submitted to the old anesthetic protocol had a higher level of pain on the first and third postoperative days than the animals submitted to the new anesthetic protocol. Conclusions: The new anesthetic protocol reduces the surgical time, allows better maintenance of the anesthetic plan, and brings more satisfactory postoperative recovery.

Histomorphometric comparison of the corpus cavernosum of rats submitted to euthanasia with ketamine and xylazine or isoflurane

ABSTRACT Purpose: To compare the penile histoarchitecture of rats euthanized with isoflurane or with ketamine and xylazine. Methods: Fourteen male rats were divided into two groups: ISO, with animals euthanized with isoflurane; and K+X, with animals euthanized with ketamine (150 mg/kg) associated with xylazine (15 mg/kg). Immediately after the death, the penises were dissected, fixed in a 4% buffered formalin solution, and processed for histomorphometric analysis. The surface densities (Sv) of the corpus cavernosum structures (connective tissue, smooth muscle, sinusoidal space, and elastic fibers) were evaluated using Image J software. The distribution of collagen types I and III was qualitatively assessed. Statistical analyses were performed using the Student's t test for data comparison, considering it statistically significant when p < 0.05. Results: Regarding the Sv of connective tissue, smooth muscle and sinusoidal space, there were no differences between animals in both groups. On the other hand, the animals euthanized with the association of ketamine and xylazine showed the Sv of elastic fibers 24.8% higher in relation to animals euthanized with isoflurane. Conclusions: The euthanasia method affected one of the morphological parameters of the rat penises. The choice of euthanasia method must be standardized to reduce bias and to obtain reliable and reproducible results.

Protocolos para contenção química e eletroejaculação para coleta de sêmen de queixadas (Tayassu pecari) / Chemical restraining and electroejaculation protocols for semen collection in white-lipped peccary (Tayassu pecari)

Background: In order to reverse the White-lipped peccary decline, besides protecting its habitat and controlling hunting,it is necessary a captive breeding program. There are reports, however, on the low fertility of white-lipped peccary, makingit difficult its reproduction in captivity, making artificial insemination one of the main tools to prevent the loss of geneticdiversity of species kept in captivity. Information on safe methods of anesthesia and the collection of semen should beinvestigated. Therefore, we aimed to compare the effects of the anesthetic protocols acepromazine/ketamine and xylazine/ketamine, as well as electroejaculation protocols, for semen collection in white-lipped peccary (Tayassu pecari).Materials, Methods & Results: Twelve adult male white-lipped peccaries were submitted both to the xylazine/ketamineand acepromazine/ketamine anesthetic protocols. The anesthetic induction time and duration, the degree of muscle relaxation, the time for anesthetic recovery and the quality of the animals’ recovery were evaluated. Additionally, the qualityof the sedation was evaluated based on the animal’s behavior. We also evaluated the effect of drugs on erectile functionsas well as the efficiency of 3 electroejaculation protocols with increasing or fixed voltages (2 to 4 V; 5 to 12 V; 12 V). Theacepromazine/ketamine combination promotes shorter induction time, duration and recovery from anesthesia than thexylazine/ketamine association. There were no differences, however, between the tested anesthetic protocols in relation toheart rate, respiratory rate and temperature. Ejaculate was obtained from only 2 animals when using the xylazine/ketamineprotocol and adoption of stimuli between 5 and 12 V, with 10 stimuli at each voltage. In turn, ejaculate was obtained from4 animals submitted to the acepromazine/ketamine protocol, 3 of them with the adoption of stimuli between 5 and 12 V...

Protocolos para contenção química e eletroejaculação para coleta de sêmen de queixadas (Tayassu pecari) / Chemical restraining and electroejaculation protocols for semen collection in white-lipped peccary (Tayassu pecari)

Background: In order to reverse the White-lipped peccary decline, besides protecting its habitat and controlling hunting,it is necessary a captive breeding program. There are reports, however, on the low fertility of white-lipped peccary, makingit difficult its reproduction in captivity, making artificial insemination one of the main tools to prevent the loss of geneticdiversity of species kept in captivity. Information on safe methods of anesthesia and the collection of semen should beinvestigated. Therefore, we aimed to compare the effects of the anesthetic protocols acepromazine/ketamine and xylazine/ketamine, as well as electroejaculation protocols, for semen collection in white-lipped peccary (Tayassu pecari).Materials, Methods & Results: Twelve adult male white-lipped peccaries were submitted both to the xylazine/ketamineand acepromazine/ketamine anesthetic protocols. The anesthetic induction time and duration, the degree of muscle relaxation, the time for anesthetic recovery and the quality of the animals recovery were evaluated. Additionally, the qualityof the sedation was evaluated based on the animals behavior. We also evaluated the effect of drugs on erectile functionsas well as the efficiency of 3 electroejaculation protocols with increasing or fixed voltages (2 to 4 V; 5 to 12 V; 12 V). Theacepromazine/ketamine combination promotes shorter induction time, duration and recovery from anesthesia than thexylazine/ketamine association. There were no differences, however, between the tested anesthetic protocols in relation toheart rate, respiratory rate and temperature. Ejaculate was obtained from only 2 animals when using the xylazine/ketamineprotocol and adoption of stimuli between 5 and 12 V, with 10 stimuli at each voltage. In turn, ejaculate was obtained from4 animals submitted to the acepromazine/ketamine protocol, 3 of them with the adoption of stimuli between 5 and 12 V...(AU)

Cardiorespiratory and hemogasometric effects of epidural ketamine and its associations with morphine and xylazine in sheep / Efeitos cardiorrespiratórios e hemogasométricos da cetamina e suas associações com morfina e xilazina por via epidural em ovinos

This study aimed to evaluate the cardiorespiratory and hemogasometric effects of epidural ketamine and its associations with morphine and xylazine in ewes submitted to transcervical cervix transposition with a hegar dilator. Ten Santa Inês breed ewes were studied in a cross over model study where three epidural protocols (GK = ketamine 2.0 mg kg-1; GKM = ketamine 2.0 mg kg-1 + morphine 0.1 mg kg-1; GKX = ketamine 2.0 mg kg-1 + xylazine 0.05 mg kg-1) were compared among each other and with a control treatment (GS= saline 1 mL/7.5 kg). The assessed variables were heart rate, respiratory frequency, ear temperature, non-invasive blood pressure and hemogasometric analysis. All parameters were assessed at baseline and then ewes were sedated with an association of acepromazine (0.1 mg kg -1) and diazepam (0.2 mg kg -1). Ten minutes after sedation all parameters were reassessed and afterwards the epidural injections were performed. Hemogasometry was repeated at 15 and 30 minutes after epidural and the other parameters assessed at 05, 15, 30, 45 and 60 minutes after epidural. GKX showed a slight respiratory depression with lower levels of PO2 and a compensatory increase in respiratory frequency. GKM presented the lower temperature mean. All protocols showed few cardiorespiratory effects when compared with control. Epidural with 2.0 mg kg-1 ketamine isolated was considered the best opti

Este estudo teve como objetivo avaliar os efeitos cardiorrespiratórios e hemogasométricos da cetamina peridural e suas associações com morfina e xilazina em ovelhas submetidas à manipulação uterina por via transcervical. Foram estudadas dez ovelhas da raça Santa Inês. Três protocolos epidurais foram avaliados: (GK = cetamina 2,0 mg kg−1, GKM = cetamina 2,0 mg kg−1 + morfina 0,1 mg kg−1, GKX = cetamina 2,0 mg kg−1 + xilazina 0,05 mg kg−1). Os três protocolos foram comparados entre si e com um tratamento controle (GS = solução salina 1 mL/7,5kg). As variáveis avaliadas foram frequência cardíaca, frequência respiratória, temperatura auricular, pressão arterial não-invasiva além da análise hemogasométrica. Todos os parâmetros foram avaliados no momento basal e em seguida as ovelhas foram sedadas com associação de acepromazina (0,1 mg kg−1) e diazepam (0,2 mg kg−1). Dez minutos após a sedação, todos os parâmetros foram novamente avaliados e foram realizadas as injeções peridurais. A hemogasometria foi repetida aos 15 e 30 minutos após a peridural e os outros parâmetros avaliados aos 05, 15, 30, 45, e 60 minutos após a peridural. O GKX mostrou sinais de hipoxemia com menores níveis de pO2 e um aumento compensatório na frequência respiratória. O GKM apresentou a média de temperatura mais baixa. Todos os protocolos apresentaram poucos efeitos cardiorrespiratórios em relação ao controle. O protocolo epidural com 2,0 mg kg−1 de cetamina foi considerado a melhor opção para procedimentos curtos como manipulações obstétricas em ovinos devido à estabilidade cardiorrespiratória quando comparado com os protocolos que utilizaram associações.(AU)

Cardiorespiratory and hemogasometric effects of epidural ketamine and its associations with morphine and xylazine in sheep / Efeitos cardiorrespiratórios e hemogasométricos da cetamina e suas associações com morfina e xilazina por via epidural em ovinos

This study aimed to evaluate the cardiorespiratory and hemogasometric effects of epidural ketamine and its associations with morphine and xylazine in ewes submitted to transcervical cervix transposition with a hegar dilator. Ten Santa Inês breed ewes were studied in a cross over model study where three epidural protocols (GK = ketamine 2.0 mg kg-1; GKM = ketamine 2.0 mg kg-1 + morphine 0.1 mg kg-1; GKX = ketamine 2.0 mg kg-1 + xylazine 0.05 mg kg-1) were compared among each other and with a control treatment (GS= saline 1 mL/7.5 kg). The assessed variables were heart rate, respiratory frequency, ear temperature, non-invasive blood pressure and hemogasometric analysis. All parameters were assessed at baseline and then ewes were sedated with an association of acepromazine (0.1 mg kg -1) and diazepam (0.2 mg kg -1). Ten minutes after sedation all parameters were reassessed and afterwards the epidural injections were performed. Hemogasometry was repeated at 15 and 30 minutes after epidural and the other parameters assessed at 05, 15, 30, 45 and 60 minutes after epidural. GKX showed a slight respiratory depression with lower levels of PO2 and a compensatory increase in respiratory frequency. GKM presented the lower temperature mean. All protocols showed few cardiorespiratory effects when compared with control. Epidural with 2.0 mg kg-1 ketamine isolated was considered the best opti

Este estudo teve como objetivo avaliar os efeitos cardiorrespiratórios e hemogasométricos da cetamina peridural e suas associações com morfina e xilazina em ovelhas submetidas à manipulação uterina por via transcervical. Foram estudadas dez ovelhas da raça Santa Inês. Três protocolos epidurais foram avaliados: (GK = cetamina 2,0 mg kg−1, GKM = cetamina 2,0 mg kg−1 + morfina 0,1 mg kg−1, GKX = cetamina 2,0 mg kg−1 + xilazina 0,05 mg kg−1). Os três protocolos foram comparados entre si e com um tratamento controle (GS = solução salina 1 mL/7,5kg). As variáveis avaliadas foram frequência cardíaca, frequência respiratória, temperatura auricular, pressão arterial não-invasiva além da análise hemogasométrica. Todos os parâmetros foram avaliados no momento basal e em seguida as ovelhas foram sedadas com associação de acepromazina (0,1 mg kg−1) e diazepam (0,2 mg kg−1). Dez minutos após a sedação, todos os parâmetros foram novamente avaliados e foram realizadas as injeções peridurais. A hemogasometria foi repetida aos 15 e 30 minutos após a peridural e os outros parâmetros avaliados aos 05, 15, 30, 45, e 60 minutos após a peridural. O GKX mostrou sinais de hipoxemia com menores níveis de pO2 e um aumento compensatório na frequência respiratória. O GKM apresentou a média de temperatura mais baixa. Todos os protocolos apresentaram poucos efeitos cardiorrespiratórios em relação ao controle. O protocolo epidural com 2,0 mg kg−1 de cetamina foi considerado a melhor opção para procedimentos curtos como manipulações obstétricas em ovinos devido à estabilidade cardiorrespiratória quando comparado com os protocolos que utilizaram associações.

Evaluation of the effects of acepromazine and xylazine on viability in an equine dermal cell line / Avaliação dos efeitos de acepromazina e xilazina na viabilidadedelinhagem celular dérmica de equino

Xylazine and acepromazine are drugs used exclusively in veterinary medicine. Xylazine is used as a sedative, analgesic, and tranquilizer while acepromazine is used as a sedative, pre-anesthetic, and anesthetic adjuvant. In vitro drug toxicity experimentation is essential to predict possible damage associated with treatment. This study was carried out to evaluate and compare the in vitro effects of acepromazine and xylazine on cell viability. Equine Dermis cells lines were used to examine different drug concentrations (0.02 mg/mL, 0.01 mg/mL, 0.005 mg/mL and 0.0025 mg/mL). An MTT assay was carried out to reveal cell viability. Both tested drugs reduced the viability of ED cells at 0.02 and 0.01 mg/mL. At 0.005 mg/mL, only acepromazine presented an effect. These results corroborate previous studies with xylazine. On the other hand, this is the first report about acepromazine and cell viability. Previous studies suggest that the mechanisms involved in reducing cell viability are apoptosis for xylazine and the activation of the autophagic pathway for acepromazine. Both mechanisms have been seen in other drugs of the same classes. These findings reveal that both acepromazine and xylazine cause concentration-dependent cytotoxicity in vitro. Future experiments could further elucidate the mechanisms by which this effect happens and thus circumvent the risk of potential tissue damag(AU)

Xilazina e acepromazina sãofármacos usados exclusivamente em medicina veterinária. A xilazina é usada como sedativo, analgésico e tranquilizante, enquanto a acepromazina é usada como sedativo, pré-anestésico e adjuvante anestésico. A experimentação de toxicidade de fármacos in vitroé essencial para prever possíveis danos associados ao tratamento. Nesse sentido, este estudo foi realizado com o objetivo de avaliar e comparar in vitroos efeitos da acepromazina e da xilazina na viabilidade celular. Células da linhagem Equine Dermis (ED) foram usadas para examinar diferentes concentrações de fármacos (0,02 mg/mL, 0,01 mg/mL, 0,005 mg/mL e 0,0025 mg/mL). O ensaio de MTT foi realizado para revelar a viabilidade celular. Ambos os fármacos testados reduziram a viabilidade das células ED em 0,02 e 0,01 mg/mL. A 0,005 mg/mL, apenas acepromazina apresentou efeito. Esses resultados corroboram estudos anteriores com xilazina. Por outro lado, este é o primeiro estudo sobre acepromazina e viabilidade celular. Estudos anteriores sugerem que os mecanismos envolvidos na redução da viabilidade celular são a apoptose para a xilazina, e a ativação da via autofágica para a acepromazina, ambos mecanismos observados em medicamentos dasmesmasclasses. Esses achados revelam que tanto a acepromazina quanto a xilazina causamcitotoxicidade in vitrodependente da concentração. Expeimentosfuturos podem elucidar ainda mais os mecanismos pelos quais esse efeito acontece e, assim, contornar o risco de possíveis danos aos tecidos.(AU)

Evaluation of the effects of acepromazine and xylazine on viability in an equine dermal cell line / Avaliação dos efeitos de acepromazina e xilazina na viabilidadedelinhagem celular dérmica de equino

Xylazine and acepromazine are drugs used exclusively in veterinary medicine. Xylazine is used as a sedative, analgesic, and tranquilizer while acepromazine is used as a sedative, pre-anesthetic, and anesthetic adjuvant. In vitro drug toxicity experimentation is essential to predict possible damage associated with treatment. This study was carried out to evaluate and compare the in vitro effects of acepromazine and xylazine on cell viability. Equine Dermis cells lines were used to examine different drug concentrations (0.02 mg/mL, 0.01 mg/mL, 0.005 mg/mL and 0.0025 mg/mL). An MTT assay was carried out to reveal cell viability. Both tested drugs reduced the viability of ED cells at 0.02 and 0.01 mg/mL. At 0.005 mg/mL, only acepromazine presented an effect. These results corroborate previous studies with xylazine. On the other hand, this is the first report about acepromazine and cell viability. Previous studies suggest that the mechanisms involved in reducing cell viability are apoptosis for xylazine and the activation of the autophagic pathway for acepromazine. Both mechanisms have been seen in other drugs of the same classes. These findings reveal that both acepromazine and xylazine cause concentration-dependent cytotoxicity in vitro. Future experiments could further elucidate the mechanisms by which this effect happens and thus circumvent the risk of potential tissue damag

Xilazina e acepromazina sãofármacos usados exclusivamente em medicina veterinária. A xilazina é usada como sedativo, analgésico e tranquilizante, enquanto a acepromazina é usada como sedativo, pré-anestésico e adjuvante anestésico. A experimentação de toxicidade de fármacos in vitroé essencial para prever possíveis danos associados ao tratamento. Nesse sentido, este estudo foi realizado com o objetivo de avaliar e comparar in vitroos efeitos da acepromazina e da xilazina na viabilidade celular. Células da linhagem Equine Dermis (ED) foram usadas para examinar diferentes concentrações de fármacos (0,02 mg/mL, 0,01 mg/mL, 0,005 mg/mL e 0,0025 mg/mL). O ensaio de MTT foi realizado para revelar a viabilidade celular. Ambos os fármacos testados reduziram a viabilidade das células ED em 0,02 e 0,01 mg/mL. A 0,005 mg/mL, apenas acepromazina apresentou efeito. Esses resultados corroboram estudos anteriores com xilazina. Por outro lado, este é o primeiro estudo sobre acepromazina e viabilidade celular. Estudos anteriores sugerem que os mecanismos envolvidos na redução da viabilidade celular são a apoptose para a xilazina, e a ativação da via autofágica para a acepromazina, ambos mecanismos observados em medicamentos dasmesmasclasses. Esses achados revelam que tanto a acepromazina quanto a xilazina causamcitotoxicidade in vitrodependente da concentração. Expeimentosfuturos podem elucidar ainda mais os mecanismos pelos quais esse efeito acontece e, assim, contornar o risco de possíveis danos aos tecidos.

Standard electrocardiographic data of peccaries (Tayassu tajacu)

Background: Peccaries (Tayassu tajacu, Linnaeus, 1758) are wild suiformes that belong to the Tayassuidae family. Electrocardiography is an important technique for cardiovascular evaluation. Analysis of various intervals, segments, complexesand waveforms of electrocardiographic (ECG) traces aids in the diagnosis of cardiac alterations and in the differentiationof congenital and acquired heart diseases from physiological cases. However, in wild animal medicine, the various patternsof normality and the evaluation of electrical traces associated with heart disease have not yet been sufficiently elucidated.The purpose of this study was to characterize the electrocardiographic (ECG) traces of peccaries sedated using ketamineand xylazine.Materials, Methods & Results: Fourteen healthy adult animals that were subjected to digital ECG examination wereused. Animals with evidence of systemic diseases, cardiovascular abnormalities (murmurs or arrhythmias), or any degreeof valve insufficiency observed on echocardiogram and animals that exhibited excessive stress during the examinationwere excluded from the study. All animals presented with a normal sinus rhythm. A combination of 15 mg/kg of ketaminehydrochloride and 3 mg/kg of midazolam maleate was applied intramuscularly for chemical immobilization. The animalswere manipulated after 15 min, when the onset of the anaesthetic effect was verified, for a duration of 45 min, and noreinforcement dose was necessary to complete the electrocardiographic examination. No significant differences wereobserved in the P-wave duration, PR interval and QT interval between genders (P > 0.05). No significant differences werefound between the amplitudes of the P and R waves between males and females (P > 0.05). The observed P waves weresmall, monophasic and positive. The QRS complex was positive in the DI, DII, DIII, aVF, V4 and V10 derivations andnegative in the aVR, aVL, V1 and V2 derivations...

Standard electrocardiographic data of peccaries (Tayassu tajacu)

Background: Peccaries (Tayassu tajacu, Linnaeus, 1758) are wild suiformes that belong to the Tayassuidae family. Electrocardiography is an important technique for cardiovascular evaluation. Analysis of various intervals, segments, complexesand waveforms of electrocardiographic (ECG) traces aids in the diagnosis of cardiac alterations and in the differentiationof congenital and acquired heart diseases from physiological cases. However, in wild animal medicine, the various patternsof normality and the evaluation of electrical traces associated with heart disease have not yet been sufficiently elucidated.The purpose of this study was to characterize the electrocardiographic (ECG) traces of peccaries sedated using ketamineand xylazine.Materials, Methods & Results: Fourteen healthy adult animals that were subjected to digital ECG examination wereused. Animals with evidence of systemic diseases, cardiovascular abnormalities (murmurs or arrhythmias), or any degreeof valve insufficiency observed on echocardiogram and animals that exhibited excessive stress during the examinationwere excluded from the study. All animals presented with a normal sinus rhythm. A combination of 15 mg/kg of ketaminehydrochloride and 3 mg/kg of midazolam maleate was applied intramuscularly for chemical immobilization. The animalswere manipulated after 15 min, when the onset of the anaesthetic effect was verified, for a duration of 45 min, and noreinforcement dose was necessary to complete the electrocardiographic examination. No significant differences wereobserved in the P-wave duration, PR interval and QT interval between genders (P > 0.05). No significant differences werefound between the amplitudes of the P and R waves between males and females (P > 0.05). The observed P waves weresmall, monophasic and positive. The QRS complex was positive in the DI, DII, DIII, aVF, V4 and V10 derivations andnegative in the aVR, aVL, V1 and V2 derivations...(AU)

Influência do uso da associação da xilazina e quetamina em Cavia porcellus, na potência de toxinas botulínicas na soro neutralização / Influence of the use of xylazine and ketamine association in Cavia porcellus on the potency of botulinum toxins and d in serum neutralization

O botulismo é uma zoonose causada pelas neurotoxinas produzidas por Clostridium botulinum. Existem oito variedades de toxinas (A-H), as toxinas C e D são as principais responsáveis por prejuízos na bovinocultura, causando óbito. Dentre as medidas preventivas eficientes, destaca-se a vacinação dos animais. Uma metodologia padrão para medir a eficiência de uma vacina é a soroneutralização in vitro tendo camundongos como sistema indicador. O objetivo do trabalho foi verificar a interferência do uso de anestésicos em Cavia porcellus vacinados sobre o efeito protetor dos soros, quando realizada a coleta de sangue para realizar a soroneutralização frente às toxinas padrões C e D. Neste trabalho foram realizados procedimentos de vacinação subcutânea, na região laterodorsal de Cavia porcellus, na dose de 5 ml no primeiro dia e repetição após 21 dias, e sangria após mais 21 dias. Foram formados dois grupos de 10 animais para cada amostra vacinal, um para sangria com o uso de associação anestésica (cloridrato de xilazina 2%, 5mg/Kg/IM e cloridrato de quetamina 10%, 25mg/Kg/IM) e outro sem uso, após isso submeteu-se o pool de soro coletado de cada grupo à soroneutralização in vitro com toxinas padrões C e D. Esses procedimentos de validação possibilitarão o seu emprego visando o bem-estar animal nos testes de controle de qualidade de vacinas. Foi observado que a aplicação de anestésicos para a punção cardíaca não interferiu no nível de proteção dos soros dos animais frente ao desafio de toxinas C e D, comparado aos não anestesiados.

Botulism is a zoonosis caused by neurotoxins produced by Clostridium botulinum. There are eight varieties of toxins (A-H), toxins C and D are main responsible for illness in cattle, causing death. Among the effective preventive measures, the vaccination of the animals stands out. To ensure adequate protection of animals, vaccines must be efficient. A standard methodology for measuring the efficiency of a vaccine is in vitro serum neutralization having mice as the indicator system. The objective of the study was to verify the interference of anesthetic use in vaccinated guinea pigs on the protective effect of sera when blood collection was performed to perform serum neutralization against standard C and D toxins. In this work, subcutaneous vaccination procedures were performed in the later dorsal region of guinea pigs at the dose of 5 ml on the first day and repetition after 21 days and bleeding after another 21 days. Two groups of 10 animals were formed for each sample de vaccine, one for bleeding with the use of an anesthetic association (xylazine hydrochloride 2%, 5mg/Kg/IM and ketamine hydrochloride 10%, 25mg/Kg/IM) and the other with no use, after which the serum mixture collected from each group were submitted to in vitro serum neutralization with standard C and D toxins. This validation study will make it possible to introduce the use this procedures aimed at animal welfare in the quality control tests of vaccines. It was observed that the application of anesthetics to cardiac puncture did not interfere in the level of protection of the sera of the animals against the challenge of toxins C and D compared to those obtained of not anesthetized animals.

Influência do uso da associação da xilazina e quetamina em Cavia porcellus, na potência de toxinas botulínicas na soro neutralização / Influence of the use of xylazine and ketamine association in Cavia porcellus on the potency of botulinum toxins and d in serum neutralization

O botulismo é uma zoonose causada pelas neurotoxinas produzidas por Clostridium botulinum. Existem oito variedades de toxinas (A-H), as toxinas C e D são as principais responsáveis por prejuízos na bovinocultura, causando óbito. Dentre as medidas preventivas eficientes, destaca-se a vacinação dos animais. Uma metodologia padrão para medir a eficiência de uma vacina é a soroneutralização in vitro tendo camundongos como sistema indicador. O objetivo do trabalho foi verificar a interferência do uso de anestésicos em Cavia porcellus vacinados sobre o efeito protetor dos soros, quando realizada a coleta de sangue para realizar a soroneutralização frente às toxinas padrões C e D. Neste trabalho foram realizados procedimentos de vacinação subcutânea, na região laterodorsal de Cavia porcellus, na dose de 5 ml no primeiro dia e repetição após 21 dias, e sangria após mais 21 dias. Foram formados dois grupos de 10 animais para cada amostra vacinal, um para sangria com o uso de associação anestésica (cloridrato de xilazina 2%, 5mg/Kg/IM e cloridrato de quetamina 10%, 25mg/Kg/IM) e outro sem uso, após isso submeteu-se o pool de soro coletado de cada grupo à soroneutralização in vitro com toxinas padrões C e D. Esses procedimentos de validação possibilitarão o seu emprego visando o bem-estar animal nos testes de controle de qualidade de vacinas. Foi observado que a aplicação de anestésicos para a punção cardíaca não interferiu no nível de proteção dos soros dos animais frente ao desafio de toxinas C e D, comparado aos não anestesiados.(AU)

Botulism is a zoonosis caused by neurotoxins produced by Clostridium botulinum. There are eight varieties of toxins (A-H), toxins C and D are main responsible for illness in cattle, causing death. Among the effective preventive measures, the vaccination of the animals stands out. To ensure adequate protection of animals, vaccines must be efficient. A standard methodology for measuring the efficiency of a vaccine is in vitro serum neutralization having mice as the indicator system. The objective of the study was to verify the interference of anesthetic use in vaccinated guinea pigs on the protective effect of sera when blood collection was performed to perform serum neutralization against standard C and D toxins. In this work, subcutaneous vaccination procedures were performed in the later dorsal region of guinea pigs at the dose of 5 ml on the first day and repetition after 21 days and bleeding after another 21 days. Two groups of 10 animals were formed for each sample de vaccine, one for bleeding with the use of an anesthetic association (xylazine hydrochloride 2%, 5mg/Kg/IM and ketamine hydrochloride 10%, 25mg/Kg/IM) and the other with no use, after which the serum mixture collected from each group were submitted to in vitro serum neutralization with standard C and D toxins. This validation study will make it possible to introduce the use this procedures aimed at animal welfare in the quality control tests of vaccines. It was observed that the application of anesthetics to cardiac puncture did not interfere in the level of protection of the sera of the animals against the challenge of toxins C and D compared to those obtained of not anesthetized animals.(AU)

Uso e efeitos da dexmedetomidina na anestesia de ratos e camundongos / Use and effects of dexmedetomidine in rats and mice anesthesia

O uso de agonistas dos receptores α-2 adrenérgicos possui ampla difusão no campo da medicina veterinária, tendo a xilazina como principal representante deste grupo anestésico. A dexmedetomidina, um isômero da medetomidina, demonstra altíssima especificidade aos adrenorreceptores α-2 e com isso vem ganhando espaço devido a seus potentes efeitos analgésicos e anestésicos e sua utilização em ratos e camundongos. Seu uso é justificado tanto como agente isolado, bem como associado a outros fármacos, visando reduzir as doses e os efeitos indesejados. A praticidade da existência de um reversor específico, o atipamezole, juntamente com a disponibilidade de administração por diversas vias, faz da dexmedetomidina uma droga adequada para utilização em roedores. Sua resposta é dose-dependente, e, por isso, deve-se avaliar cautelosamente o tipo de anestesia desejada previamente à sua administração. A dexmedetomidina demostra uma série de efeitos anti-inflamatórios e protetores sistêmicos, visto que inibe citocinas pró-inflamatórias. No entanto, tais mecanismos de ação ainda não foram completamente elucidados. A especificidade da dexmedetomidina aliada a seu potente potencial analgésico e anestésico, além de seus efeitos secundários como anti-inflamatório e protetor sugerem sua utilização na anestesia de ratos e camundongos de forma segura.

The use of α-2 agonist adrenoreceptors is widespread in veterinary, and xilazine represents the major role of the group. Dexmedetomidine, a medetomidine isomer, is highly specific to the α-2 adrenoreceptors and due to analgesic and anesthetic effects, it’s use in rats and mice can be seen as single agent or associated with other drugs, to reduce dose and minimize the side effects. The convenience of having a specific revert drug, atipamezole, makes dexmedetomidine a safe drug to be administered to rodents, besides the possibility of being administered by multiple ways. The response of dexmedetomidine is dose-dependent and, because of that, the anesthesia protocol should be careful evaluated before its administration. Besides, the drug shows several anti-inflammatory and protective effects decurrent of its use, inhibiting pro-inflammatory citokines, but the mechanisms haven’t been completely elucidated. The high specifity of dexmedetomidine associated to the analgesic and anesthetic effects, plus its secondary effects as anti-inflammatory and protector suggests a safe use in rats and mice anesthesia.

Analgesia epidural com xilazina ou detomidina em cães submetidos a procedimentos ortopédicos / Epidural analgesia with xylazine or detomidine in dogs undergoing orthopedic procedures

Os agonistas dos α2-adrenorreceptores podem ser classificados como sedativo-hipnóticos e têm propriedades adicionais miorrelaxantes e analgésicas, portanto, por apresentarem tais características, eles são alternativas ao uso dos opioides, via epidural. Assim, foram avaliados em catorze cães os efeitos analgésicos e cardiorrespiratórios causados pela injeção epidural de xilazina ou detomidina, para comparar o grau de analgesia proporcionado por ambos. Utilizou-se a escala de Melbourne, considerando como critérios para a administração da analgesia de resgate uma pontuação de 13 pontos. Os grupos não apresentaram diferenças significativas e não necessitaram de resgate analgésico. A conclusão foi que os dois fármacos produzem analgesia intensa durante os períodos transcirúrgico e pós-operatório sem causar qualquer depressão respiratória, bradicardia ou hipotensão.

The agonists of α2-adrenoceptors may be classified as a sedativehypnotic and have additional myorelaxant and analgesic properties, therefore, for presenting such characteristics, they are alternatives to using opioids, via epidural. Thus, it was evaluated in fourteen dogs the analgesic and cardiorespiratory effects caused by epidural injection of xylazine or detomidine, to compare the level of analgesia provided by both products. The range of Melbourne was applied for performing the comparison, considering as criteria for the administration of analgesia rescue a score of 13 points. Both groups did no present any significant changes and not required analgesic rescue. The conclusion was that the two drugs produce intense analgesia during the transurgical and postoperative periods without any effect on respiratory depression, bradycardia or hypotension.

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) [...]

Analgesia epidural com xilazina ou detomidina em cães submetidos a procedimentos ortopédicos / Epidural analgesia with xylazine or detomidine in dogs undergoing orthopedic procedures

Os agonistas dos α2-adrenorreceptores podem ser classificados como sedativo-hipnóticos e têm propriedades adicionais miorrelaxantes e analgésicas, portanto, por apresentarem tais características, eles são alternativas ao uso dos opioides, via epidural. Assim, foram avaliados em catorze cães os efeitos analgésicos e cardiorrespiratórios causados pela injeção epidural de xilazina ou detomidina, para comparar o grau de analgesia proporcionado por ambos. Utilizou-se a escala de Melbourne, considerando como critérios para a administração da analgesia de resgate uma pontuação de 13 pontos. Os grupos não apresentaram diferenças significativas e não necessitaram de resgate analgésico. A conclusão foi que os dois fármacos produzem analgesia intensa durante os períodos transcirúrgico e pós-operatório sem causar qualquer depressão respiratória, bradicardia ou hipotensão.(AU)

The agonists of α2-adrenoceptors may be classified as a sedativehypnotic and have additional myorelaxant and analgesic properties, therefore, for presenting such characteristics, they are alternatives to using opioids, via epidural. Thus, it was evaluated in fourteen dogs the analgesic and cardiorespiratory effects caused by epidural injection of xylazine or detomidine, to compare the level of analgesia provided by both products. The range of Melbourne was applied for performing the comparison, considering as criteria for the administration of analgesia rescue a score of 13 points. Both groups did no present any significant changes and not required analgesic rescue. The conclusion was that the two drugs produce intense analgesia during the transurgical and postoperative periods without any effect on respiratory depression, bradycardia or hypotension.(AU)