Neurobiología y modulación de la hipertermia inducida por estrés agudo y fiebre en los animales

Abstract

La hipertermia inducida por estrés es una respuesta aguda que se presenta a corto plazo en individuos que están frente a un estímulo estresante y que dicha respuesta puede aportar información significativa sobre el grado de estrés. Sin embargo, no es claro todavía si la vía neurológica pueda ser modificada al mismo grado en la que se percibe el estrés. Además, no se tiene suficiente claridad en cómo es que los factores que modifican el grado de percepción de estrés actúan sobre la Hipertermia Inducida por Estrés (SIH, por sus siglas en inglés). Asimismo, las investigaciones señalan que posiblemente la respuesta térmica tenga una mayor influencia cardiovascular al generar el consumo de recursos energéticos. De igual manera, los factores físicos que inducen dicha respuesta han sido cuestionados, ya que la evidencia reciente señala que además los factores sociales como la presencia de coespecíficos atenúan la respuesta térmica pero cuando se impide la convivencia o alguna otra conducta social como la crianza, la respuesta incrementa la SIH. Por tal motivo, el objetivo de este artículo es analizar la neurobiología de la hipertermia inducida por estrés y su diferencia conceptual con la fiebre infecciosa, así como integrar los factores que lo modulan, analizando los avances científicos recientes de la respuesta térmica inducida por estrés.

Clinical Applications and Factors Involved in Validating Thermal Windows Used in Infrared Thermography in Cattle and River Buffalo to Assess Health and Productivity

“…This technique detects the heat irradiated by a surface, decoding it into a temperature by a biological body, and interpreting its relation to the state of animal comfort [5]. In terms of both physiological and practical mechanisms, the principal mechanism involved in heat gain or loss is the regulation of the diameter of near-surface blood vessels; that is, the cutaneous vasodilatation that occurs in anatomical regions to permit thermal exchanges with the environment [6][7][8][9][10][11]. These regions, known as thermal windows [12][13][14][15][16], are characterized by a dense network of blood vessels, the presence of plexus, arteriovenous anastomosis, and the absence of hair [7,8].…”

“…In terms of both physiological and practical mechanisms, the principal mechanism involved in heat gain or loss is the regulation of the diameter of near-surface blood vessels; that is, the cutaneous vasodilatation that occurs in anatomical regions to permit thermal exchanges with the environment [6][7][8][9][10][11]. These regions, known as thermal windows [12][13][14][15][16], are characterized by a dense network of blood vessels, the presence of plexus, arteriovenous anastomosis, and the absence of hair [7,8]. Various authors sustain that these regions permit evaluating the state of health of an animal in a non-stressful manner [17][18][19][20][21].…”

Assessment of Pain and Inflammation in Domestic Animals Using Infrared Thermography: A Narrative Review

“…This also occurs in the locus coeruleus and the thalamus, transmitting nociceptive information to the somatosensory cortex, hypothalamus, and hippocampus [ 30 , 31 ]. Through this mechanism, pain induces the activation of the hypothalamic-pituitary-adrenal axis, the sympathetic nervous system, and, consequently, the release of glucocorticoids [ 32 , 33 ]. On the other hand, activation of the sympathetic-adrenomedullary system alters cardiovascular function due to catecholamine secretion by activating adrenoceptors in the vascular endothelium [ 34 , 35 ].…”

Efficacy and Function of Feathers, Hair, and Glabrous Skin in the Thermoregulation Strategies of Domestic Animals

“…Studies of animals with feathers using invasive techniques have correlated circulating cortisol levels with the ocular region’s temperatures under caloric stress conditions ( Figure 7 ) [ 31 ]. It should be noted that the ocular region is widely used in domestic animals to determine the increase in body temperature in response to the activation of the sympathetic nervous system under stressful conditions such as stress hyperthermia [ 120 ]. This effect is observed as an increase in the superficial temperature of the orbital region [ 121 , 122 ].…”