RESUMO
The temperature gradients are dynamic and noninvasive monitoring techniques that provide information on peripheral blood flow and have been related to the prognosis of patients with circulatory shock. This study evaluated 47 elderly domestic cats' temperature gradients, and we measured central (rectal) and peripheral (palmar, plantar and medial region of the radio) temperatures. Values found in this study are compatible with studies in young felines and differ from dogs and humans. The mean gradients found were 7.5°C for the central-peripheral; 5.6°C for the peripheral-environmental; 2.7°C for the skin-diff; and 0°C for the member-diff and the variables age and gender do not seem to influence these measurements. To the authors' knowledge, there is no description of temperature gradients in elderly domestic cats, so this study pretends to clarify the vasoconstriction response in this group of animals.(AU)
Os gradientes de temperatura são técnicas de monitoração dinâmicas e não-invasivas que fornecem informações sobre o fluxo sanguíneo periférico, e têm sido relacionados ao prognóstico de paciente com choque circulatório. O presente estudo avaliou os gradientes de temperatura em 47 felinos domésticos idosos aferindo as temperaturas central (retal) e periférica (palmar, plantar e região medial do rádio). Os gradientes encontrados foram 7,5°C para o centro-periférico; 5,6°C para o periférico-ambiental; 2,7°C para o skin-diff; e 0°C para o member-diff. As variáveis idade e sexo não pareceram influenciar as mensurações. Não há, em conhecimento dos autores, descrição prévia dos gradientes de temperatura em felinos domésticos idosos, e por isso esse estudo pretende contribuir com o entendimento sobre a capacidade de resposta de vasoconstrição nesse grupo de animais.(AU)
Assuntos
Animais , Gatos , Choque/diagnóstico , Choque/prevenção & controle , Pele/irrigação sanguínea , Vasoconstrição , Temperatura Corporal , TermômetrosRESUMO
Several ecological hypotheses try to explain geographical patterns in biodiversity. The Metabolic Theory of Ecology (MTE) predicts that temperature is the main determinant of richness patterns for ectothermic organisms and that the relationship between richness (lnS) and temperature (1/kT) is a linear relationship with angular coefficient (b) near -0.65. This study tested the MTE for continental zooplankton diversity in 63 lakes in Brazil. Copepoda, Cladocera and Rotifera, as well as the three groups combined, showed different patterns from that predicted by MTE, with b values equal to 0.871, 0.516, 0.720 and 0.901, respectively. Temperature explains 12.7% of the richness of Copepoda, 5.3% of Cladocera, 6.7% of Rotifera, and 11.4% of all zooplankton groups together. Several studies have shown that the MTE does not apply to many terrestrial groups, perhaps because the model does not consider variances generated by other factors such as environmental spatial range, body size and other variables. The present study confirms this point of view, expanding it to continental aquatic invertebrates as well.
Várias hipóteses ecológicas tentam explicar os padrões geográficos de biodiversidade. A Teoria Metabólica da Ecologia (Metabolic Theory of Ecology - MTE) prediz que a temperatura é o principal determinante dos padrões de riqueza de organismos ectotérmicos e que a relação entre riqueza (lnS) e temperatura (1/kT) é uma reta com coeficiente angular (b) próximo a -0,65. O presente estudo testou a MTE para a diversidade zooplanctônica continental em 63 lagos brasileiros. Copepoda, Cladocera e Rotifera, assim como os três grupos analisados em conjunto, apresentaram padrões diferentes do previsto pela MTE, com os valores de b iguais a 0,871; 0,516; 0,720 e 0,901, respectivamente. A temperatura explicou 12,7% da riqueza de Copepoda, 5,3% de Cladocera, 6,7% de Rotifera e 11,4% do zooplâncton total. Diversos trabalhos têm demonstrado que a MTE não se aplica a muitos grupos terrestres, talvez porque o modelo não prevê desvios ocasionados por fatores como a variação espacial no ambiente, o tamanho corporal e outras variáveis. O presente trabalho corrobora este ponto de vista, expandindo-o também para invertebrados aquáticos continentais.
Assuntos
Animais , Rotíferos , Temperatura , Cladocera , Copépodes , Biodiversidade , EcologiaRESUMO
Several ecological hypotheses try to explain geographical patterns in biodiversity. The Metabolic Theory of Ecology (MTE) predicts that temperature is the main determinant of richness patterns for ectothermic organisms and that the relationship between richness (lnS) and temperature (1/kT) is a linear relationship with angular coefficient (b) near -0.65. This study tested the MTE for continental zooplankton diversity in 63 lakes in Brazil. Copepoda, Cladocera and Rotifera, as well as the three groups combined, showed different patterns from that predicted by MTE, with b values equal to 0.871, 0.516, 0.720 and 0.901, respectively. Temperature explains 12.7% of the richness of Copepoda, 5.3% of Cladocera, 6.7% of Rotifera, and 11.4% of all zooplankton groups together. Several studies have shown that the MTE does not apply to many terrestrial groups, perhaps because the model does not consider variances generated by other factors such as environmental spatial range, body size and other variables. The present study confirms this point of view, expanding it to continental aquatic invertebrates as well. macroecology; biodiversity; Copepoda; Cladocera; Rotífera; temperature gradients