Blubber and serum cortisol concentrations as indicators of the stress response and overall health status in striped dolphins

The impacts of environmental changes and anthropogenic threats in marine mammals are a growing concern for their conservation. In recent years, efforts have been directed to understand how marine mammals cope with stressors and to assess and validate stress biomarkers, mainly levels of glucocorticoid hormones (e.g. cortisol) in certain body tissues. The aims of this study were to assess the impact of different causes of stranding (chronically affected and bycaught striped dolphins) on cortisol concentrations in serum and in blubber; and to evaluate the association between cortisol levels in these tissues. Blubber and blood samples were collected from striped dolphins (n = 42) stranded on the Mediterranean coast between 2012 and 2018. Cortisol concentrations were measured by using enzyme immunoassay. A high correlation was found between circulating and blubber cortisol concentrations (R2 = 0.85, p < 0.01). Necropsies and pathological studies concluded that a third of the dolphins were bycaught in fishing nets and released by fishermen (Bycaught animals group), while the other two thirds were euthanized, or died, due to a disease or chronic condition (e.g. calves separated from the mother or animals infected with dolphin morbillivirus or Brucella ceti) that impeded survival (Chronically affected animals group). Cortisol concentrations (mean ± SD) were six times higher in chronically affected animals (35.3 ± 23 ng cortisol/g blubber and 6.63 ± 3.22 μg cortisol/dl serum) compared to those bycaught in fishing nets (6.2 ± 4.3 ng cortisol/g blubber and 1.15 ± 1.51 μg cortisol/dl serum). Results suggests that serum and blubber cortisol concentrations can contribute in inferring the overall health and welfare of free-ranging cetaceans. However, further research is required to understand better the kinetics of blubber cortisol incorporation and removal, the factors involved in these processes, and the local conversion of cortisol in the blubber.info:eu-repo/semantics/publishedVersio

Blubber and serum cortisol concentrations as indicators of the stress response and overall health status in striped dolphins

Altres ajuts: acord transformatiu CRUE-CSICThe impacts of environmental changes and anthropogenic threats in marine mammals are a growing concern for their conservation. In recent years, efforts have been directed to understand how marine mammals cope with stressors and to assess and validate stress biomarkers, mainly levels of glucocorticoid hormones (e.g. cortisol) in certain body tissues. The aims of this study were to assess the impact of different causes of stranding (chronically affected and bycaught striped dolphins) on cortisol concentrations in serum and in blubber; and to evaluate the association between cortisol levels in these tissues. Blubber and blood samples were collected from striped dolphins (n = 42) stranded on the Mediterranean coast between 2012 and 2018. Cortisol concentrations were measured by using enzyme immunoassay. A high correlation was found between circulating and blubber cortisol concentrations (R = 0.85, p < 0.01). Necropsies and pathological studies concluded that a third of the dolphins were bycaught in fishing nets and released by fishermen (Bycaught animals group), while the other two thirds were euthanized, or died, due to a disease or chronic condition (e.g. calves separated from the mother or animals infected with dolphin morbillivirus or Brucella ceti) that impeded survival (Chronically affected animals group). Cortisol concentrations (mean ± SD) were six times higher in chronically affected animals (35.3 ± 23 ng cortisol/g blubber and 6.63 ± 3.22 μg cortisol/dl serum) compared to those bycaught in fishing nets (6.2 ± 4.3 ng cortisol/g blubber and 1.15 ± 1.51 μg cortisol/dl serum). Results suggests that serum and blubber cortisol concentrations can contribute in inferring the overall health and welfare of free-ranging cetaceans. However, further research is required to understand better the kinetics of blubber cortisol incorporation and removal, the factors involved in these processes, and the local conversion of cortisol in the blubber

NR3C1 and glucocorticoid-regulatory genes mRNA and protein expression in the endometrium and ampulla during the bovine estrous cycle

Altres ajuts: acord transformatiu CRUE-CSICThe bovine reproductive tract exhibits changes during the estrous cycle modulated by the interplay of steroid hormones. Glucocorticoids can be detrimental when stress-induced but are relevant at baseline levels for appropriate reproductive function. Here, an analysis of quantitative real-time PCR was performed to study the bovine glucocorticoid-related baseline gene transcription in endometrial and ampullar tissue samples derived from three time points of the estrous cycle, stage I (Days 1-4), stage III (Days 11-17) and stage IV (Days 18-20). Our results revealed expression differences during stages, as expression observed in the ampulla was higher during the post-ovulatory phase (stage I), including the glucocorticoid receptor NR3C1, and some of its regulators, involved in glucocorticoid availability (HSD11B1 and HSD11B2) and transcriptional actions (FKBP4 and FKBP5). In contrast, in the endometrium, higher expression of the steroid receptors was observed during the late luteal phase (stage III), including ESR1, ESR2, PGRMC1 and PGRMC2, and HSD11B1 expression decreased, while HSD11B2 increased. Moreover, at protein level, FKBP4 was higher expressed during the late luteal phase, and NR3C1 during the pre-ovulatory phase (stage IV). These results suggest that tight regulation of the glucocorticoid activity is promoted in the ampulla, when reproductive events are taking place, including oocyte maturation. Moreover, most expression changes in the endometrium were observed during the late luteal phase, and may be related to the embryonic maternal recognition. In conclusion, the glucocorticoid regulation changes across the estrous cycle and may be playing a role on the reproductive events occurring in the bovine ampulla and endometrium

A protein-coding gene expression atlas from the brain of pregnant and non-pregnant goats

Background: The brain is an extraordinarily complex organ with multiple anatomical structures involved in highly specialized functions related with behavior and physiological homeostasis. Our goal was to build an atlas of protein-coding gene expression in the goat brain by sequencing the transcriptomes of 12 brain regions in seven female Murciano-Granadina goats, from which three of them were 1-month pregnant. Results: Between 14,889 (cerebellar hemisphere) and 15,592 (pineal gland) protein-coding genes were expressed in goat brain regions, and most of them displayed ubiquitous or broad patterns of expression across tissues. Principal component analysis and hierarchical clustering based on the patterns of mRNA expression revealed that samples from certain brain regions tend to group according to their position in the anterior-posterior axis of the neural tube, i.e., hindbrain (pons and medulla oblongata), midbrain (rostral colliculus) and forebrain (frontal neocortex, olfactory bulb, hypothalamus, and hippocampus). Exceptions to this observation were cerebellum and glandular tissues (pineal gland and hypophysis), which showed highly divergent mRNA expression profiles. Differential expression analysis between pregnant and non-pregnant goats revealed moderate changes of mRNA expression in the frontal neocortex, hippocampus, adenohypophysis and pons, and very dramatic changes in the olfactory bulb. Many genes showing differential expression in this organ are related to olfactory function and behavior in humans. Conclusion: With the exception of cerebellum and glandular tissues, there is a relationship between the cellular origin of sampled regions along the anterior-posterior axis of the neural tube and their mRNA expression patterns in the goat adult brain. Gestation induces substantial changes in the mRNA expression of the olfactory bulb, a finding consistent with the key role of this anatomical structure on the development of maternal behavior

A protein-coding gene expression atlas from the brain of pregnant and non-pregnant goats

[Background] The brain is an extraordinarily complex organ with multiple anatomical structures involved in highly specialized functions related with behavior and physiological homeostasis. Our goal was to build an atlas of protein-coding gene expression in the goat brain by sequencing the transcriptomes of 12 brain regions in seven female Murciano-Granadina goats, from which three of them were 1-month pregnant.[Results] Between 14,889 (cerebellar hemisphere) and 15,592 (pineal gland) protein-coding genes were expressed in goat brain regions, and most of them displayed ubiquitous or broad patterns of expression across tissues. Principal component analysis and hierarchical clustering based on the patterns of mRNA expression revealed that samples from certain brain regions tend to group according to their position in the anterior-posterior axis of the neural tube, i.e., hindbrain (pons and medulla oblongata), midbrain (rostral colliculus) and forebrain (frontal neocortex, olfactory bulb, hypothalamus, and hippocampus). Exceptions to this observation were cerebellum and glandular tissues (pineal gland and hypophysis), which showed highly divergent mRNA expression profiles. Differential expression analysis between pregnant and non-pregnant goats revealed moderate changes of mRNA expression in the frontal neocortex, hippocampus, adenohypophysis and pons, and very dramatic changes in the olfactory bulb. Many genes showing differential expression in this organ are related to olfactory function and behavior in humans.[Conclusion] With the exception of cerebellum and glandular tissues, there is a relationship between the cellular origin of sampled regions along the anterior-posterior axis of the neural tube and their mRNA expression patterns in the goat adult brain. Gestation induces substantial changes in the mRNA expression of the olfactory bulb, a finding consistent with the key role of this anatomical structure on the development of maternal behavior.This research was funded by the European Regional Development Fund (FEDER)/Ministerio de Ciencia e Innovación—Agencia Estatal de Investigación/Project Reference grants: AGL2016-76108-R and also by project PID2019-105805RB-I00 funded by MCIN/AEI/10.13039/501100011033. We also acknowledge the support of the CERCA Programme/Generalitat de Catalunya and of the Spanish Ministry of Economy and Competitivity for the Center of Excellence Severo Ochoa 2020-2023 (CEX2019-000902-S) grant awarded to the Centre for Research in Agricultural Genomics (CRAG, Bellaterra, Spain). Maria Luigi-Sierra was funded with a PhD fellowship “Formación de Personal Investigador” (BES-2017-079709) awarded by the Spanish Ministry of Economy and Competitivity and by “ESF Investing in your future”. Dailu Guan was funded by a PhD fellowship from the China Scholarship Council (CSC). Emilio Mármol-Sánchez was funded with a FPU Ph.D. grant from the Spanish Ministry of Education (FPU15/01733).With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000902-S)Peer reviewe

A protein-coding gene expression atlas from the brain of pregnant and non-pregnant goats

Background: The brain is an extraordinarily complex organ with multiple anatomical structures involved in highly specialized functions related with behavior and physiological homeostasis. Our goal was to build an atlas of protein-coding gene expression in the goat brain by sequencing the transcriptomes of 12 brain regions in seven female Murciano-Granadina goats, from which three of them were 1-month pregnant.Results: Between 14,889 (cerebellar hemisphere) and 15,592 (pineal gland) protein-coding genes were expressed in goat brain regions, and most of them displayed ubiquitous or broad patterns of expression across tissues. Principal component analysis and hierarchical clustering based on the patterns of mRNA expression revealed that samples from certain brain regions tend to group according to their position in the anterior-posterior axis of the neural tube, i.e., hindbrain (pons and medulla oblongata), midbrain (rostral colliculus) and forebrain (frontal neocortex, olfactory bulb, hypothalamus, and hippocampus). Exceptions to this observation were cerebellum and glandular tissues (pineal gland and hypophysis), which showed highly divergent mRNA expression profiles. Differential expression analysis between pregnant and non-pregnant goats revealed moderate changes of mRNA expression in the frontal neocortex, hippocampus, adenohypophysis and pons, and very dramatic changes in the olfactory bulb. Many genes showing differential expression in this organ are related to olfactory function and behavior in humans.Conclusion: With the exception of cerebellum and glandular tissues, there is a relationship between the cellular origin of sampled regions along the anterior-posterior axis of the neural tube and their mRNA expression patterns in the goat adult brain. Gestation induces substantial changes in the mRNA expression of the olfactory bulb, a finding consistent with the key role of this anatomical structure on the development of maternal behavior

Cavalls participants en les festes patronals de Menorca : caracterització fisiològica de la resposta d'estrès i protocol d'avaluació del seu benestar

Els cavalls s'han utilitzat per a diverses finalitats al llarg de la història. Aquest fet, i motivat per un increment d'interès substancial per part de la societat en el benestar dels animals, ha propiciat en els últims anys l'estudi i caracterització de la resposta d'estrès que es genera en els animals destinats a participar en activitats recreatives. Des d'almenys el s. XIV a Menorca, cada estiu, se celebren les festes en honor als patrons dels pobles que conformen l'Illa, on el cavall n'és el protagonista principal. Durant les festes patronals els cavalls es poden exposar a una sèrie de factors que poden ser potencialment estressants. Conèixer quin és l'efecte d'aquesta exposició és una primera aproximació per determinar el grau d'impacte a nivell fisiològic que tenen les celebracions en els cavalls que hi participen. En el primer estudi de la present tesi doctoral es van mesurar les variacions estacionals de cortisol, testosterona i sulfat de deshidroepiandrosterona (DHEA-S) i les seves ràtios en pèl al llarg d'un any com a mesura retrospectiva de l'activitat dels eixos hipotalàmic-hipofisiari-adrenal i gonadal. Els resultats d'aquest estudi van mostrar un efecte estacional per totes les hormones avaluades i també per les seves ràtios. A diferència de l'observat en les concentracions de testosterona i DHEA-S, les concentracions de cortisol van mostrar un increment progressiu des de l'hivern fins a l'estiu. El segon estudi es va realitzar amb la finalitat d'estimar la resposta d'estrès a través de l'anàlisi del cortisol salival, plasmàtic, i un estudi hematològic complet durant una sessió d'entrenament estàndard per participar en les festes patronals de l'illa. Els resultats obtinguts van mostrar com les concentracions de cortisol salival i plasmàtic incrementaven significativament després d'una hora d'entrenament en comparació als nivells obtinguts previs a la sessió. Paral·lelament es va reportar el retorn de les concentracions de cortisol als seus nivells basals més ràpidament en saliva en comparació amb el plasma. Aquesta troballa suggereix l'ús de la saliva com una millor matriu per a monitorar el retorn als nivells de cortisol basal en cavalls exposats a un exercici. El tercer estudi tenia l'objectiu d'estimar la resposta d'estrès mitjançant l'anàlisi del cortisol salival en cavalls durant la celebració de les festes patronals de Maó (Menorca, Espanya). Per primera vegada, aquest estudi descrivia la resposta d'estrès generada per la participació dels animals en els actes. Els resultats van mostrar com les concentracions de cortisol salival augmentaven progressivament, assolint les concentracions màximes el segon dia de les celebracions, i tornant als valors basals l'endemà dels actes, suggerint les celebracions com un estressor agut i transitori. En quart lloc, es va dissenyar, adaptar i establir l'aplicació d'un protocol d'avaluació del benestar dels cavalls participats en les festes patronals de Menorca. Pel disseny del protocol es va realitzar una adaptació dels protocols prèviament validats per l'avaluació del benestar de cavalls utilitzats per activitats recreatives i esportives i que tractés de garantir un enfocament holístic que comprengués les diferents dimensions del benestar animal. En el protocol proposat es van incloure 4 principis, 8 criteris i 16 indicadors basats en l'animal i l'ambient. En conclusió, la present tesi doctoral ofereix una base experimental per avaluar de forma objectiva la resposta d'estrès i el benestar de cavalls destinats a participar en activitats culturals i tradicionals.Los caballos han sido utilizados para diversos fines a lo largo de la historia. Este hecho y motivado por un incremento de interés substancial por parte de la sociedad en el bienestar animal, ha propiciado en los últimos años el estudio y caracterización de la respuesta de estrés que se genera en animales destinados a participar en actividades recreativas. Desde por lo menos el S. XIV en Menorca, cada verano se celebran las fiestas patronales en honor a los patrones de los pueblos que conforman la Isla, en donde el caballo es el protagonista principal. Durante las fiestas patronales, los caballos pueden ser expuestos a una serie de factores que pueden ser potencialmente estresantes. Conocer cuál es el efecto de esta exposición es una primera aproximación para determinar el impacto a nivel fisiológico que tienen las celebraciones en los caballos que participan. En el primer capítulo de la presente tesis doctoral se midieron las variaciones estacionales de cortisol, testosterona y sulfato de dehidroepiandrosterona (DHEA-S) y sus ratios en pelo a lo largo de un año como medida retrospectiva de la actividad de los ejes hipotalámico-hipofisario-adrenal y gonadal. Los resultados de este estudio mostraron un efecto estacional en todas las hormonas evaluadas, así como también en sus ratios. A diferencia de lo observado en las concentraciones de testosterona y DHEA-S, las concentraciones de cortisol mostraron un incremento progresivo desde invierno hasta verano. El segundo estudio se realizó con el fin de estimar la respuesta fisiológica de estrés mediante la cuantificación del cortisol salival y plasmático, y las variaciones en la biometría hemática en caballos durante una sesión de entrenamiento estándar para participar en las fiestas patronales de Menorca. Los resultados obtenidos mostraron como las concentraciones de cortisol salival y plasmático incrementaban significativamente después de una hora de entrenamiento en comparación a los niveles previos al mismo. Paralelamente se reportó el retorno de las concentraciones de cortisol a sus niveles basales más rápidamente en saliva en comparación con el plasma. Este hallazgo sugiere el uso de la saliva como una mejor matriz para monitorizar el retorno a los niveles de cortisol basal en caballos expuestos a un ejercicio. El tercer estudio tenía el objetivo de estimar la respuesta fisiológica de estrés mediante la medida del cortisol salival en caballos durante la celebración de las fiestas patronales de Maó (Menorca, España). Por primera vez, este estudio describía la respuesta de estrés generada por la participación de los animales en los actos. Los resultados nos mostraron como las concentraciones de cortisol salival aumentaron progresivamente, obteniendo las concentraciones máximas en el segundo día de las celebraciones, y volviendo a los valores basales al día siguiente a los actos, postulando así las celebraciones como un estresor agudo y transitorio. En cuarto lugar, se diseñó, adaptó y estableció la aplicación de un protocolo de evaluación del bienestar de los caballos participantes en las fiestas patronales de Menorca. Para el diseño del protocolo se realizó una adaptación de los protocolos previamente validados para la evaluación del bienestar de caballos utilizados para fines recreativos y deportivos para garantizar un enfoque holístico que comprendiera las diferentes dimensiones del bienestar animal. En el protocolo propuesto se incluyeron 4 principios, 8 criterios y 16 indicadores basados en el animal y en el ambiente. En conclusión, la presente tesis doctoral ofrece una base experimental para evaluar de forma objetiva la respuesta de estrés y el bienestar de caballos destinados a participar en actividades culturales y tradicionales.Historically horses have been used for different tasks and purposes, including recreational activities. In a more animal welfare-conscious society, the use of horses for human-related purposes has motivated the study and characterization of their stress response. Since the XIVth century, horses have been the main character in Menorca's patronal festivals. In these traditional festivals, horses may be exposed to potentially stressful factors. Studying the effect of this exposure is a first approach to determine the physiological impact of the celebrations on the participant horses. In the first study of the present thesis, cortisol, testosterone, and dehydroepiandrosterone sulfate (DHEA-S) seasonal variations and their ratios were assessed as a retrospective measure of the hypothalamic-hypophysis-adrenal and gonadal axis activity. Results showed a seasonal effect on all the evaluated hormones and their ratios. Contrary to testosterone and DHEA-S, cortisol concentrations increased progressively from winter to summer. The second study was performed to evaluate the stress response by measuring saliva and serum cortisol and the variations of the complete blood count during a training session for the festivals. Results showed a significant increase in salivary and plasma cortisol levels after an hour of training compared to the baseline levels. Salivary cortisol concentrations returned faster to baseline than serum, suggesting this as a better return-to-baseline cortisol measurement matrix in exercised horses. The objective of the third study was to evaluate the physiological stress response by measuring the salivary cortisol levels on patronal festivals in Maó (Menorca, Spain). Results showed how salivary cortisol levels raised to a maximum peak on the festival's second day and decreased to baseline levels within the day after the end of the festival. This finding suggests that festivals generated an acute and transitory stress response. Lastly, an animal welfare protocol was designed, adapted, and implemented for participating horses in the Menorca patronal festivals. Previous welfare validated protocols were used as a model for the design to ensure a more holistic and complete approach to animal welfare. The designed protocol included 4 principles, 8 criteria, and 16 indicators based on "animal-based" and "resource-based" indicators. Overall, the present thesis offers an experimental basis to objectively assess the stress response and welfare of horses used in cultural and traditional activities

Cavalls participants en les festes patronals de Menorca: caracterització fisiològica de la resposta d'estrès i protocol d'avaluació del seu benestar

Els cavalls s’han utilitzat per a diverses finalitats al llarg de la història. Aquest fet, i motivat per un increment d’interès substancial per part de la societat en el benestar dels animals, ha propiciat en els últims anys l’estudi i caracterització de la resposta d’estrès que es genera en els animals destinats a participar en activitats recreatives. Des d’almenys el s. XIV a Menorca, cada estiu, se celebren les festes en honor als patrons dels pobles que conformen l’Illa, on el cavall n’és el protagonista principal. Durant les festes patronals els cavalls es poden exposar a una sèrie de factors que poden ser potencialment estressants. Conèixer quin és l’efecte d’aquesta exposició és una primera aproximació per determinar el grau d’impacte a nivell fisiològic que tenen les celebracions en els cavalls que hi participen. En el primer estudi de la present tesi doctoral es van mesurar les variacions estacionals de cortisol, testosterona i sulfat de deshidroepiandrosterona (DHEA-S) i les seves ràtios en pèl al llarg d’un any com a mesura retrospectiva de l’activitat dels eixos hipotalàmic-hipofisiari-adrenal i gonadal. Els resultats d’aquest estudi van mostrar un efecte estacional per totes les hormones avaluades i també per les seves ràtios. A diferència de l’observat en les concentracions de testosterona i DHEA-S, les concentracions de cortisol van mostrar un increment progressiu des de l’hivern fins a l’estiu. El segon estudi es va realitzar amb la finalitat d’estimar la resposta d’estrès a través de l’anàlisi del cortisol salival, plasmàtic, i un estudi hematològic complet durant una sessió d’entrenament estàndard per participar en les festes patronals de l’illa. Els resultats obtinguts van mostrar com les concentracions de cortisol salival i plasmàtic incrementaven significativament després d’una hora d’entrenament en comparació als nivells obtinguts previs a la sessió. Paral·lelament es va reportar el retorn de les concentracions de cortisol als seus nivells basals més ràpidament en saliva en comparació amb el plasma. Aquesta troballa suggereix l’ús de la saliva com una millor matriu per a monitorar el retorn als nivells de cortisol basal en cavalls exposats a un exercici. El tercer estudi tenia l’objectiu d’estimar la resposta d’estrès mitjançant l’anàlisi del cortisol salival en cavalls durant la celebració de les festes patronals de Maó (Menorca, Espanya). Per primera vegada, aquest estudi descrivia la resposta d’estrès generada per la participació dels animals en els actes. Els resultats van mostrar com les concentracions de cortisol salival augmentaven progressivament, assolint les concentracions màximes el segon dia de les celebracions, i tornant als valors basals l’endemà dels actes, suggerint les celebracions com un estressor agut i transitori. En quart lloc, es va dissenyar, adaptar i establir l’aplicació d’un protocol d’avaluació del benestar dels cavalls participats en les festes patronals de Menorca. Pel disseny del protocol es va realitzar una adaptació dels protocols prèviament validats per l’avaluació del benestar de cavalls utilitzats per activitats recreatives i esportives i que tractés de garantir un enfocament holístic que comprengués les diferents dimensions del benestar animal. En el protocol proposat es van incloure 4 principis, 8 criteris i 16 indicadors basats en l’animal i l’ambient. En conclusió, la present tesi doctoral ofereix una base experimental per avaluar de forma objectiva la resposta d’estrès i el benestar de cavalls destinats a participar en activitats culturals i tradicionals.Los caballos han sido utilizados para diversos fines a lo largo de la historia. Este hecho y motivado por un incremento de interés substancial por parte de la sociedad en el bienestar animal, ha propiciado en los últimos años el estudio y caracterización de la respuesta de estrés que se genera en animales destinados a participar en actividades recreativas. Desde por lo menos el S. XIV en Menorca, cada verano se celebran las fiestas patronales en honor a los patrones de los pueblos que conforman la Isla, en donde el caballo es el protagonista principal. Durante las fiestas patronales, los caballos pueden ser expuestos a una serie de factores que pueden ser potencialmente estresantes. Conocer cuál es el efecto de esta exposición es una primera aproximación para determinar el impacto a nivel fisiológico que tienen las celebraciones en los caballos que participan. En el primer capítulo de la presente tesis doctoral se midieron las variaciones estacionales de cortisol, testosterona y sulfato de dehidroepiandrosterona (DHEA-S) y sus ratios en pelo a lo largo de un año como medida retrospectiva de la actividad de los ejes hipotalámico-hipofisario-adrenal y gonadal. Los resultados de este estudio mostraron un efecto estacional en todas las hormonas evaluadas, así como también en sus ratios. A diferencia de lo observado en las concentraciones de testosterona y DHEA-S, las concentraciones de cortisol mostraron un incremento progresivo desde invierno hasta verano. El segundo estudio se realizó con el fin de estimar la respuesta fisiológica de estrés mediante la cuantificación del cortisol salival y plasmático, y las variaciones en la biometría hemática en caballos durante una sesión de entrenamiento estándar para participar en las fiestas patronales de Menorca. Los resultados obtenidos mostraron como las concentraciones de cortisol salival y plasmático incrementaban significativamente después de una hora de entrenamiento en comparación a los niveles previos al mismo. Paralelamente se reportó el retorno de las concentraciones de cortisol a sus niveles basales más rápidamente en saliva en comparación con el plasma. Este hallazgo sugiere el uso de la saliva como una mejor matriz para monitorizar el retorno a los niveles de cortisol basal en caballos expuestos a un ejercicio. El tercer estudio tenía el objetivo de estimar la respuesta fisiológica de estrés mediante la medida del cortisol salival en caballos durante la celebración de las fiestas patronales de Maó (Menorca, España). Por primera vez, este estudio describía la respuesta de estrés generada por la participación de los animales en los actos. Los resultados nos mostraron como las concentraciones de cortisol salival aumentaron progresivamente, obteniendo las concentraciones máximas en el segundo día de las celebraciones, y volviendo a los valores basales al día siguiente a los actos, postulando así las celebraciones como un estresor agudo y transitorio. En cuarto lugar, se diseñó, adaptó y estableció la aplicación de un protocolo de evaluación del bienestar de los caballos participantes en las fiestas patronales de Menorca. Para el diseño del protocolo se realizó una adaptación de los protocolos previamente validados para la evaluación del bienestar de caballos utilizados para fines recreativos y deportivos para garantizar un enfoque holístico que comprendiera las diferentes dimensiones del bienestar animal. En el protocolo propuesto se incluyeron 4 principios, 8 criterios y 16 indicadores basados en el animal y en el ambiente. En conclusión, la presente tesis doctoral ofrece una base experimental para evaluar de forma objetiva la respuesta de estrés y el bienestar de caballos destinados a participar en actividades culturales y tradicionales.Historically horses have been used for different tasks and purposes, including recreational activities. In a more animal welfare-conscious society, the use of horses for human-related purposes has motivated the study and characterization of their stress response. Since the XIVth century, horses have been the main character in Menorca’s patronal festivals. In these traditional festivals, horses may be exposed to potentially stressful factors. Studying the effect of this exposure is a first approach to determine the physiological impact of the celebrations on the participant horses. In the first study of the present thesis, cortisol, testosterone, and dehydroepiandrosterone sulfate (DHEA-S) seasonal variations and their ratios were assessed as a retrospective measure of the hypothalamic-hypophysis-adrenal and gonadal axis activity. Results showed a seasonal effect on all the evaluated hormones and their ratios. Contrary to testosterone and DHEA-S, cortisol concentrations increased progressively from winter to summer. The second study was performed to evaluate the stress response by measuring saliva and serum cortisol and the variations of the complete blood count during a training session for the festivals. Results showed a significant increase in salivary and plasma cortisol levels after an hour of training compared to the baseline levels. Salivary cortisol concentrations returned faster to baseline than serum, suggesting this as a better return-to-baseline cortisol measurement matrix in exercised horses. The objective of the third study was to evaluate the physiological stress response by measuring the salivary cortisol levels on patronal festivals in Maó (Menorca, Spain). Results showed how salivary cortisol levels raised to a maximum peak on the festival’s second day and decreased to baseline levels within the day after the end of the festival. This finding suggests that festivals generated an acute and transitory stress response. Lastly, an animal welfare protocol was designed, adapted, and implemented for participating horses in the Menorca patronal festivals. Previous welfare validated protocols were used as a model for the design to ensure a more holistic and complete approach to animal welfare. The designed protocol included 4 principles, 8 criteria, and 16 indicators based on “animal-based” and “resource-based” indicators. Overall, the present thesis offers an experimental basis to objectively assess the stress response and welfare of horses used in cultural and traditional activities.Universitat Autònoma de Barcelona. Programa de Doctorat en Medicina i Sanitat Animal

Non-invasive measurement of glucocorticoids : The reptile perspective

Altres ajuts: acords transformatius de la UABRecent advancements in stress physiology, driven by the relevance of the stress response in animal welfare and conservation, have focused on alternative techniques beyond blood sampling for measuring glucocorticoids (GC). While blood samples have been traditionally used, practical and ethical concerns have spurred exploration into minimally invasive media like saliva, feces, milk, hair, and feathers. This review addresses the dearth of research on reptile endocrinology, offering insights into measuring GC or their metabolites in reptiles through various biological tissues. It underscores the importance of considering temporal dynamics in stress response evaluation and advocates for further exploration of alternative tools to enhance our understanding of reptilian stress responses

Cortisol Variations to Estimate the Physiological Stress Response in Horses at a Traditional Equestrian Event

In many countries, horses remain involved in traditional equestrian events such as those celebrated in Menorca (Balearic Islands, Spain) every year since at least the 14th century. The present study aimed to evaluate the variations in salivary cortisol concentrations to estimate the physiological stress response in horses at the Menorca patronal festivals. Two different editions (years 2016 and 2018) of the festivals in honor of the Virgin of Grace in Ma&oacute; (Menorca, Spain) were studied. Nineteen and seventeen Pure Breed Menorca stallions were included in the study, respectively. The stallions were aged between seven and twelve years. During celebrations, samples were collected before the start of the festivals between 8&ndash;9 a.m. and during the festivals at 8&ndash;9 p.m. On the second day of celebrations, the samples were collected at 8&ndash;9 a.m. and 3&ndash;4 p.m. Finally, on the day after the festivals, one sample was collected at 8&ndash;9 p.m. Additionally, a control group was sampled at 8&ndash;9 a.m., 3&ndash;4 p.m., and 8&ndash;9 p.m. Salivary cortisol concentrations were assessed by using a commercial enzyme immunoassay kit specially validated to quantify salivary cortisol in horses. Salivary cortisol concentrations did not show significant differences between sampling hours in the control group (p &gt; 0.05). All the samples collected during festivals were significantly higher than samples of the control group (p &lt; 0.05). Within the twenty-four hours after the end of the celebrations, cortisol concentrations returned to baseline levels and did not differ significantly from the control group (p &gt; 0.05). Hence, the present study describes that the participation of the horses in these particular acts generate an acute and transitory stress response. Overall, the current work provides a reasonable basis for future research on the stress physiology and well-being of horses participating in traditional celebrations or similar events