317 research outputs found

    Behavioural, endocrine and cardiac autonomic responses to a model of startle in horses

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    Startle is a fast response elicited by sudden acoustic, tactile or visual stimuli in a variety of animal species and in humans. The magnitude of startle response can be modulated by external and internal variables and can be a useful tool to study the sensory-motor integration in animals. Different stimuli have been used to induce startle in horses, which makes it difficult to compare the responses to these different approaches. The present study uses ultra-short-term heart rate variability (HRV) analysis to characterize the cardiac autonomic modulation, reactivity assessment and blood cortisol measurements to describe the behavioural and endocrine responses to a simple, easy to replicate, effective and safe method of startle (an umbrella is abruptly opened near the horse). The ultra-short-term (64 s) heart rate (HR) series were interpolated (4 Hz) and divided into 256 points segments then the spectra calculated (Fast Fourier Transform). The spectra were then integrated into low (LF; 0.01–0.07 Hz; Index of Cardiac Sympathetic Modulation) and high (HF; 0.07–0.50 Hz; Index of Cardiac Parasympathetic Modulation) frequency bands. Following the startle test, the HR (p = 0.0101), the power of the LF band of the cardiac interval spectrum (p = 0.0002) and the LF/HF ratio (p = 0.0066) were found to be higher, whereas the power of the HF band of the cardiac interval spectrum was found to be lower (p = 0.0002). Also, the horses showed a noticeable escape response, with latency of reaction varying from 0.28 to 1.28 s, duration of reaction ranging from 1.52 to 7.92 s and escape distance covered varying from 3.43 to 9.97 m. However, the endocrine measurements failed to reveal significant changes in the cortisol levels after the startle test. We conclude that the startle test used in the current study was effective to produce changes in behavioural parameters and cardiac autonomic modulation of the horses and can therefore be an appropriate tool for neurobiological studies. Furthermore, the use of ultra-short segments (64 s) for HRV analysis appears to be effective and promising for the detection of mental stress in horses.Instituto de Genética Veterinari

    Behavioural, endocrine and cardiac autonomic responses to a model of startle in horses

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    Startle is a fast response elicited by sudden acoustic, tactile or visual stimuli in a variety of animal species and in humans. The magnitude of startle response can be modulated by external and internal variables and can be a useful tool to study the sensory-motor integration in animals. Different stimuli have been used to induce startle in horses, which makes it difficult to compare the responses to these different approaches. The present study uses ultra-short-term heart rate variability (HRV) analysis to characterize the cardiac autonomic modulation, reactivity assessment and blood cortisol measurements to describe the behavioural and endocrine responses to a simple, easy to replicate, effective and safe method of startle (an umbrella is abruptly opened near the horse). The ultra-short-term (64. s) heart rate (HR) series were interpolated (4. Hz) and divided into 256 points segments then the spectra calculated (Fast Fourier Transform). The spectra were then integrated into low (LF; 0.01-0.07. Hz; Index of Cardiac Sympathetic Modulation) and high (HF; 0.07-0.50. Hz; Index of Cardiac Parasympathetic Modulation) frequency bands. Following the startle test, the HR (p = 0.0101), the power of the LF band of the cardiac interval spectrum (p = 0.0002) and the LF/HF ratio (p = 0.0066) were found to be higher, whereas the power of the HF band of the cardiac interval spectrum was found to be lower (p = 0.0002). Also, the horses showed a noticeable escape response, with latency of reaction varying from 0.28 to 1.28. s, duration of reaction ranging from 1.52 to 7.92. s and escape distance covered varying from 3.43 to 9.97. m. However, the endocrine measurements failed to reveal significant changes in the cortisol levels after the startle test. We conclude that the startle test used in the current study was effective to produce changes in behavioural parameters and cardiac autonomic modulation of the horses and can therefore be an appropriate tool for neurobiological studies. Furthermore, the use of ultra-short segments (64 s) for HRV analysis appears to be effective and promising for the detection of mental stress in horses.Fil: Villas Boas, Julia Dias. Universidade Federal do Estado do Rio de Janeiro; BrasilFil: Martins Dias, Daniel Penteado. Universidade de Sao Paulo; BrasilFil: Trigo, Pablo Ignacio. Universidade Federal do Estado do Rio de Janeiro; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: dos Santos Almeida, Norma Aparecida. Universidade Federal do Estado do Rio de Janeiro; BrasilFil: de Almeida, Fernando Queiroz. Universidade Federal do Estado do Rio de Janeiro; BrasilFil: de Madeiros, Magda Alves. Universidade Federal do Estado do Rio de Janeiro; Brasi

    Acupuncture affects autonomic and endocrine but not behavioural responses induced by startle in horses

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    Startle is a fast response elicited by sudden acoustic, tactile, or visual stimuli in a variety of animals and in humans. As the magnitude of startle response can be modulated by external and internal variables, it can be a useful tool to study reaction to stress. Our study evaluated whether acupuncture can change cardiac autonomic modulation (heart rate variability); and behavioural (reactivity) and endocrine (cortisol levels) parameters in response to startle. Brazilian Sport horses (n = 6) were subjected to a model of startle in which an umbrella was abruptly opened near the horse. Before startle, the horses were subjected to a 20-minute session of acupuncture in acupoints GV1, HT7, GV20, and BL52 (ACUP) and in nonpoints (NP) or left undisturbed (CTL). For analysis of the heart rate variability, ultrashort-term (64 s) heart rate series were interpolated (4 Hz) and divided into 256-point segments and the spectra integrated into low (LF; 0.01–0.07 Hz; index of sympathetic modulation) and high (HF; 0.07–0.50 Hz; index of parasympathetic modulation) frequency bands. Acupuncture (ACUP) changed the sympathovagal balance with a shift towards parasympathetic modulation, reducing the prompt startle-induced increase in LF/HF and reducing cortisol levels 30 min after startle. However, acupuncture elicited no changes in behavioural parameters.Instituto de Genética Veterinari

    Pharmacopuncture Versus Acepromazine in Stress Responses of Horses During Road Transport

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    AbstractAcupuncture has been shown to have the beneficial effect of reducing stress responses in animals and humans. Pharmacopuncture is the injection of subclinical doses of drugs into acupoints to give therapeutic results without side effects. This study compared the effects of injecting the usual dose of acepromazine (ACP; 0.1 mg/kg, intramuscularly [I.M.]) with those of pharmacopuncture (1/10 ACP dose at the governing vessel 1 [GV 1] acupoint) on the stress responses of healthy horses undergoing road transport for 2.5 hours. Four different treatments were applied immediately before loading, with 8 animals/treatment: injection of saline or ACP (0.1 mg/kg, I.M.) at the base of the neck; and injection of saline or 1/10 ACP (0.01 mg/kg) at the GV 1 acupoint. The road transport increased heart rate (HR), respiratory rate, body temperature, and serum cortisol of the untreated horses (injected with saline at the base of the neck). Pharmacopuncture at GV 1 reduced the average HR and transport-induced increase in HR at unloading, without changing the other variables. On the other hand, ACP (0.1 mg/kg) produced significant sedation and reduced the transport-induced increase in respiratory rate but without preventing the stress-induced increase of cortisol. Other acupuncture points and drugs should be tested to verify the beneficial effect of this therapy to reduce stress in horses during road transport

    Direct Determination of Malachite Green and Leucomalachite Green in Natural Waters by Exploiting Solid-phase Sorption and Digital Image

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    Although malachite green (MG), a triphenylmethane dye, is banned for use in aquaculture in several countries, it is still widely employed to treat infections in fish and fish eggs. In living organisms, it is reduced to leucomalachite green (LMG) during physiological processes and can accumulate in adipose tissue. This work describes the development and verification of a simple and portable method, using preconcentration on an adsorbent surface and digital image analysis, for the determination of malachite green and leucomalachite green in natural waters. The optimum conditions of production and extraction in the film were evaluated univariate and the images were analyzed with the aid of Image J. The analytical curves were obtained from each color channel, using multiple linear regression (MLR) models for all parameters of the RGB system. Malachite green was adsorbed on a Florisil surface, followed by quantification using a calibration curve obtained with RGB image parameters, with the preconcentration factor was close to 10.  Accuracy was assessed using recovery tests on river natural waters samples, showing no significant matrix effect or additive error. The technique is suitable for environmental monitoring purposes. Simple method, practical and versatile. DOI: http://dx.doi.org/10.17807/orbital.v12i4.149

    Infiltração de leucócitos e imunorreatividade antimieloperoxidase em granulócitos da mucosa e submucosa do intestino grosso de equinos submetidos à sobrecarga dietética com amido

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    Este estudo teve como objetivo avaliar a infiltração de leucócitos e a imunorreatividade antimieloperoxidase em granulócitos da mucosa e submucosa do intestino grosso de equinos submetidos à sobrecarga dietética com amido. Oito equinos adultos foram distribuídos aleatoriamente em três tratamentos: Tratamento I (Controle) (n = 2), equinos eutanasiados sem sobrecarga com amido; Tratamento II (n = 3) e III (n = 3), equinos submetidos à sobrecarga com amido, com infusão gástrica de 17,6 g de amido/kg de peso vivo e eutanasiados após 24 e 36 horas, respectivamente. Observou-se apenas afluxo de neutrófilos (leucocitoestase) nos vasos sanguíneos da mucosa e submucosa intestinal. Eosinófilos foram as células predominantes na mucosa e submucosa em todos os equinos, independente da sobrecarga dietética, com grau de infiltração de leve a moderada. Infiltração por linfócitos também foi observado em todos os equinos, porém com menor intensidade quando comparado aos eosinófilos. Congestão, edema e dilatação de vasos linfáticos foram as principais alterações circulatórias observadas, com maior intensidade na submucosa. Maior imunorreatividade para anticorpos antimieloperoxidase foi observado na mucosa e submucosa dos equinos 36 horas após a sobrecarga. Equinos submetidos à sobrecarga dietética com amido apresentam resposta inflamatória intestinal com predominância de eosinófilos, leucocitoestase e alterações circulatórias variando de discreta a moderada.This study was carried out to evaluate leukocyte infiltration and anti-myeloperoxidase immunoreactivity in granulocytes of the mucosa and submucosa of the large intestine of horses submitted to dietetic starch overload. Eight adult horses were allocated randomly in three treatments: Treatment I (Control) (n = 2), animals euthanized without starch overload; and Treatments II (n = 3) and III (n = 3), animals undergoing starch overload, with gastric infusion of 17.6 g starch per kg of body weight, euthanized after 24 and 36 hours, respectively. Only afflux of neutrophils in the intestinal mucosa and submucosa blood vessels (leukocyte stasis) was observed. Eosinophils were the predominant cells in the mucosa and submucosa in all horses, independent of dietetic overload, with infiltration grade from mild to moderate. Lymphocyte infiltration was also observed in all horses, but with lower intensity when compared to eosinophils. Congestion, edema and dilatation of lymphatic vessels were the main circulatory alterations observed, with more intensity in the submucosa. Higher immunoreactivity to the anti-myeloperoxidase antibodies was observed in the mucosa and submucosa of horses 36 hours after overload. Horses submitted to dietetic starch overload showed intestinal inflammatory response with prevalence of eosinophils, leukocyte stasis and circulatory alterations, varying from discreet to moderate

    Qualidade do solo em função dos teores de matéria orgânica em área estabelecida de sistema agroflorestal sucessional em Uberlândia – MG: Soil quality as a function of organic matter content in established area of agricultural successional system in Uberlandia – MG

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    Presume-se que existe estreita relação do teor de matéria orgânica com as demais propriedades físicas, químicas e biológicas de um solo, sendo assim de fundamental importância um manejo sustentável para a manutenção da capacidade produtiva do solo a longo prazo. Sendo assim, o projeto teve como objetivo analisar a qualidade do solo (QS) em um sistema Agroflorestal Sintrópico de 2 anos e meio de implementação (que antes consistia em uma área de pasto), em função dos teores de matéria orgânica. Para isso, foram coletadas seis amostras compostas, formadas por três amostras simples, entre as linhas de cada cultura, nas profundidades de 0 a 5 e de 5 a 20 cm, na área agroflorestal do Instituto Federal de Educação, Ciência e Tecnologia do Triângulo Mineiro, campus Uberlândia – MG. Foram obtidos resultados significativos tanto para o teor de matéria orgânica, sendo a média de 28,10 g.dm-3 para as linhas e de 33,77 g.dm-3 para as entrelinhas, quanto para o teor de carbono, sendo a média de 16,30 g.dm-3 para as linhas, e de 19,59 g.dm-3 para as entrelinhas, o que indica que os Sistemas Agroflorestais parecem ser uma opção favorável para agricultores que desejam manter seus sistemas produtivos, mas também seus recursos abundantes e seu solo vivo e saudável

    Assimetrias e similaridades na produção de cavalos no sul do Brasil e Argentina: produtividade, aspectos sanitários e comerciais

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    This study was carried out in order to verify the asymmetries and similarities in horse breeding in the Brazilian South region and Argentina, analyzing the productive, health and trade aspects. Data collection were performed with questionnaires in fieldwork (primary sources) and bibliographic searches and surveys (secondary sources). The sample consisted of horses breeders in Brazil, Rio Grande do Sul State, and in Argentina. The questionnaire was based on the Brazilian Study of Horse Agribusiness Complex, divided into: Production Aspects, Health Issues and trade aspects. Descriptive data analysis and relative frequencies were compared using the chi-square (χ2 ) test at 5% probability. It was observed that there was a similarity in several aspects related to the breeding and trade horse agribusiness, whereas in the health aspects there was asymmetry in certain aspects. In the Southern Brazil, 29.0% of the owners live in the breeding farm and 67.7% have another remunerated activity. There was a similarity in the endoparasites system control and an asymmetry in the ectoparasites control. There was a higher percentage of diseases control in Argentina, which may be related to technification and qualification of workforce. However, regarding the equine sanitary control, there was a similarity between the farms of Southern Brazil and Argentina. Despite of all asymmetries and similarities, there is a relevance of horse agribusiness on generating jobs and income source, as well as the cultural and economic contribution in both countries. Furthermore, there is a necessity of public policies from government authority to promote the horse industry.O objetivo com este estudo foi observar as similaridades e asimetrias existentes na criação de cavalos no sul do Brasil e Argentina, a partir de análise dos aspectos produtivos, comerciais e da saúde dos equinos. A metodologia utilizada compreendeu levantamento de dados, através de aplicação de questionário a campo (fontes primárias) e pesquisas bibliográficas (fontes secundárias). A amostragem abrangeu criadores de equinos do Rio Grande do Sul e Argentina. O questionário foi elaborado baseado no Estudo do Complexo do Agronegócio Cavalo no Brasil, dividido em: Aspectos de Proodução, Sanitários e Comerciais. Foi realizada análise descritiva dos dados e as frequências relativas foram comparadas pelo teste Qui-quadrado (P<0,05). Observou-se similaridades nos aspectos relacionados à criação e comercialização, mas assimetria relacionada à saúde dos equinos. No sul do Brasil 29,0% dos proprietários vivem da criação de cavalos, enquanto 67,7% exercem outras atividades remuneradas. Observou-se similaridade no controle de endoparasitas e assimetria em relação à ectoparasitas. A alta percentagem de controle de doenças observada na Argentina pode estar relacionada à tecnificação e a mão de obra treinada. Contudo, observou-se similaridade entre as fazendas do sul do Brasil e Argentina em relação ao controle sanitário dos rebanhos de equinos. A respeito das diversas assimetrias e semelhanças observadas, destaca-se a importância do agronegócio cavalo na produção de emprego e renda, bem como a contribuição econômica e cultural para ambos os países. Além disso, há necessidade de políticas públicas para a promoção da indústria do cavalo.Instituto de Genética Veterinari
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