Changes in cortisol and cortisone in hair of pigs reared under heat stress conditions

Heat stress accounts for millions of dollars in losses for swine producers worldwide. The aim of the present study was to determine and evaluate cortisol and cortisone in hair as indicators of thermal stress in growing pigs reared under high environmental temperatures. The study was carried out in two independent batches of commercial crosses of Lean Duroc and Pietrain in trials 1 and 2, respectively, during the growing period (from 40 to 100 kg; 81 days in trial 1 and 77 days in trial 2) in the same commercial farm in Spain during the summers of 2020 and 2021. In both cases, four rooms were used. In Trial 1, Room 1 had cooling and 11 pigs per pen; Room 2 had no cooling and 13 pigs per pen; Room 3 had no cooling and 11 pigs per pen, and Room 4 had cooling and 13 pigs per pen. In Trial 2, Rooms 2 and 3 had cooling and rooms 1 and 4 had no cooling, and all of them had 13 pigs per pen. Mean THI value was higher (p < 0.0001) in rooms without cooling systems (75.0 trial 1; 74.9 trial 2) than with them (71.3 trial 1; 71.7 trial 2). A total of four pens per room (16 in total) was selected for analysis of hair corticoids and all pigs inside were sampled at the end of the study. Fifty percent of the pigs were males (castrated and intact in trial 1 and 2, respectively) and 50% females. In total, 44, 52, 44, and 52 pigs, respectively, were sampled in four rooms from the first trial and 52 for each of four rooms in Trial 2. Cortisol concentrations in hair did not show any significant change in relation to cooling-non-cooling in any trial. However, hair cortisone concentration was 172.3 pg./mg and 105.8 pg./ mg less (p < 0.001) in pigs housed with cooling systems compared to those without them in Trial 1 and 2, respectively. In addition, the cortisone/cortisol ratio, which is an estimator of the activity of 11β-hydroxysteroid dehydrogenase (11β-HSD) type 2, was also greater in rooms without cooling than in rooms with cooling in both trials (p < 0.0001 and p = 0.0105 for Trials 1 and 2, respectively). In relation to the sex effect, the results showed greater levels in females than in castrated males both in cortisone and the cortisol/cortisone ratio while cortisol hair levels were greater in intact males than in females. Therefore, the use of cortisone and the estimation of 11β-HSD type 2 activity in hair is recommended to evaluate the chronic stress produced by high environmental conditions in pigs instead of using hair cortisol concentrations alone.This study was included in Vall Companys, S.A.U.’s project WELFARE+ 8IDI-20210216 co-funded by Centre for the Development of Industrial Technology (CDTI), a Public Business Entity, answering to the Ministry of Science and Innovation, and the European Regional Development Fund (ERDF). DE was funded by the postdoctoral contract “Generational renewal to promote research” of the University of Murcia. ML-A (FJC2021-047105-I) by means of a post-doctoral fellowship, “Juan de la Cierva Formación,” supported by the “Ministerio de Ciencia e Innovación.”info:eu-repo/semantics/publishedVersio

Reducing Stocking Densities and Using Cooling Systems for More Adapted Pigs to High Temperatures When Reared in Intensive Conditions

This study is aimed at evaluating the effect of reducing stocking density and using cooling systems to mitigate the negative effects of high temperatures in growing pigs (females and castrated males) reared in intensive conditions (from 25 to 100 kg) during summer (June to October 2020). The experimental design was a 2 × 2 factorial where pigs were provided with an evaporative cooling system and/or raised at regular or at lower stocking densities (i.e., 0.68 to 0.80 m2/animal). Treatments were distributed in four different rooms containing sex-balanced pens with either castrated males or females. Temperature and humidity were recorded throughout the experiment, and the temperature–humidity index was calculated. Heat stress (HS) on pigs was measured through changes in animals’ performance, animal-based indicators (dirtiness and activity budget) and physiological indicators (neutrophil/lymphocyte ratio and hair cortisol). The use of cooling, lowering stocking density and the combination of both strategies had positive effects on pigs’ final body weight (+5 kg, +3 kg, +9 kg, respectively; p < 0.001). The prevalence of dirtiness was similar at the stocking densities tested, and no clear effect of the cooling system was found. Both mitigation strategies lowered the physiological indicators of stress, although only hair cortisone can be considered an indicator of HS. In conclusion, both mitigation strategies are effective in improving pig welfare and performance, especially when both are combined. The severity of the stocking density effect may depend on the severity of the temperature.This study was included in Vall Companys, S.A.U.’s project WELFARE+ 8IDI-20210216 co-funded by the Centre for the Development of Industrial Technology (CDTI), a Public Business Entity, answering to the Ministry of Science and Innovation, and the European Regional Development Fund (ERDF). D.E. was funded by the postdoctoral contract “Generational renewal to promote research” of the University of Murcia. M.L.-A. (FJC2021-047105-I) by means of a post-doctoral fellowship, “Juan de la Cierva Formación”, supported by the “Ministerio de Ciencia e Innovación”.info:eu-repo/semantics/publishedVersio

Oxytocin changes in saliva of sows kept in different farrowing systems

Oral session 2[EN] Farrowing systems can influence the behaviour of sows during lactation -including their interaction with piglets and ability to move around-, hence improving their welfare. Oxytocin has been associated with positive emotions, and consequently to welfare improvement. The purpose of this study was to compare the welfare of sows through salivary oxytocin concentrations in three different farrowing systems during lactation and shortly after weaning

Fecal Microbiota and Hair Glucocorticoid Concentration Show Associations with Growth during Early Life in a Pig Model

Identifying characteristics associated with fast or slow growth during early life in a pig model will help in the design of nutritional strategies or recommendations during infancy. The aim of this study was to identify if a differential growth during lactation and/or the nursery period may be associated with fecal microbiota composition and fermentation capacity, as well as to leave a print of glucocorticoid biomarkers in the hair. Seventy-five commercial male and female pigs showing extreme growth in the lactation and nursery periods were selected, creating four groups (First, lactation growth, d0-d21; second, nursery growth, d21-d62): Slow_Slow, Slow_Fast, Fast_Slow, and Fast_Fast. At d63 of life, hair and fecal samples were collected. Fast-growing pigs during nursery had higher cortisone concentrations in the hair (p < 0.05) and a tendency to have a lower cortisol-to-cortisone ratio (p = 0.061). Both lactation and nursery growth conditioned the fecal microbiota structure (p < 0.05). Additionally, fast-growing pigs during nursery had higher evenness (p < 0.05). Lactation growth influenced the relative abundance of eight bacterial genera, while nursery growth affected only two bacterial genera (p < 0.05). The fecal butyrate concentration was higher with fast growth in lactation and/or nursery (p < 0.05), suggesting it has an important role in growth, while total SCFA and acetate were related to lactation growth (p < 0.05). In conclusion, piglets' growth during nursery and, especially, the lactation period was associated with changes in their microbiota composition and fermentation capacity, evidencing the critical role of early colonization on the establishment of the adult microbiota. Additionally, cortisol conversion to cortisone was increased in animals with fast growth, but further research is necessary to determine its implication

Trace Elements and Ferritin in Pig Saliva : Variations during Fattening, Time of Sampling, Effect of Dirtiness and Stability under Different Storage Conditions

Altres ajuts: The European Next Generation Funds RYC2021-033660-IThe objective of this study was to evaluate the possible changes of zinc (Zn), copper (Cu), iron (Fe) and ferritin during the entire productive cycle in fattening pigs and at different diurnal sampling times. Moreover, the possible effects of the presence of pen contaminants and storage stability at different temperature conditions were assessed. The analytes changed along the different phases of the fattening productive cycle, showing, in general, higher values at the initial phases. In addition, statistically significant variations were found in Zn and Cu measurements at different sampling times of the day. In the spectrophotometric assays, the values of all analytes significantly increased after adding high concentrations of feces or feed. However, when low concentrations of feces or feed were added, only Cu showed a significant increase. Overall, the salivary levels of Zn, Cu, Fe and ferritin in pigs can change during different fattening phases and the different hours of the day. These analytes were more stable at −80 °C and, if saliva is contaminated with feces or feed, it can lead to an increase in these analytes

Investigation of correlations between skin lesion count and concentrations of salivary biomarkers in pigs from suckling to fattening

Oral session 1[EN] ClearFarm project intends to develop a platform to monitor animal welfare continuously throughout the value chain of pigs and dairy cattle using sensor technology. This platform relies on algorithms (for each species), built up with relevant welfare indicators measured by PLF (Precision Livestock Farming) technology

Prolactin in saliva of pigs as a possible biomarker of stress: analytical validation of an immunoassay and changes at slaughterhouse

Oral session 2[EN] Prolactin (PRL) is considered a biomarker of stress response, both acute and chronic, in several species. Although the scientific literature reports divergent results, some studies suggest that prolactin secretion during stress acts to maintain homeostasis within the immune system. Several studies have investigated the possibility of measuring PRL in saliva in different species such as rats, domestic ruminants, donkeys, dogs, cattle, and sheep for diagnosis or research purposes. Results obtained in animal models have indicated that the secretion of this hormone is dependent on the type and intensity of the stress

Evaluation of the Effect of Sampling Time on Biomarkers of Stress, Immune System, Redox Status and Other Biochemistry Analytes in Saliva of Finishing Pigs

Saliva is a sample with a high potential in pigs since it is usually easy to obtain and its collection from animals causes less stress than blood sampling. However, the possible effects of daily variations in many salivary biomarkers are still unknown in this species. In our report, the possible variations depending on the sampling time in the day in a panel of 26 salivary biomarkers related to stress, immune system, redox status and other physiological functions in the saliva of pigs were evaluated. In our experimental conditions, daily variations were observed in cortisol, α-amylase, total esterase, butyrylcholinesterase, lipase, adenosine deaminase isoenzyme 1, uric acid, superoxide dismutase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, creatine kinase, lactate dehydrogenase, triglycerides and lactate. In some analytes, these differences appeared in both sexes, whereas others only showed differences in one sex. These variations should be taken into consideration for an appropriate interpretation of these analytes in the saliva of healthy pigs. This study aims to evaluate the possible variations due to the sampling time in the day in 26 analytes of pigs' saliva, related to stress, the immune system, redox status and other biomarkers related to metabolism and selected tissues and organs, in order to know the possible effects of the hour of the day in their interpretation. These analytes were measured in saliva obtained from a population of 40 clinically healthy pigs from 8 a.m. to 8 p.m., every 4 h in the same day. In our experimental conditions, daily variations were observed in cortisol, salivary α-amylase, total esterase activity, butyrylcholinesterase, lipase, adenosine deaminase isoenzyme 1, uric acid, superoxide dismutase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, creatine kinase, lactate dehydrogenase, lactate and triglycerides. These changes appeared in both sexes, except for adenosine deaminase isoenzyme 1 and superoxide dismutase which only showed differences in females. In conclusion, this report indicates that, in the experimental conditions of this trial, the time of the day and sex can influence the values obtained in various salivary analytes in pigs. These variations should thus be taken into consideration for an adequate interpretation of these analytes when used for the evaluation of health and welfare in this species

Changes in a Comprehensive Profile of Saliva Analytes in Fattening Pigs during a Complete Productive Cycle : A Longitudinal Study

The aim of this study was to evaluate whether a panel of 29 salivary biomarkers of stress, immunity, inflammation, redox homeostasis and other physiological functions can change in healthy fattening pigs when monitoring the different phases of their productive cycle and can be influenced by various sources of variations such as gender and performance parameters. Several analytes showed changes due to the productive cycle, with a majority of the analytes showing higher values at lactation and at the beginning of nursery. Additionally, differences were seen due to sex. These differences can be related in some cases with performance parameters and should be taken into consideration for an appropriate interpretation of the analytes. A comprehensive panel of 29 salivary analytes was measured in fattening pigs to evaluate its possible changes along their productive cycle. The identification of those changes would allow a better interpretation of the results according to the productive phase of the animal. Saliva samples were obtained from 49 Large-White pigs (24 females, 25 males) in suckling phase, at the beginning and the end of the nursery phase, and at the beginning and the end of the growing phase. Several analytes changed according to the phase of the productive cycle, with most of the analytes showing higher values at lactation and at the beginning of nursery. Additionally, differences were seen due to sex. When possible relations between performance parameters and analytes were evaluated, significant positive but weak relationships were found between weight at birth and salivary γ-glutamyl transferase, and between back-fat thickness and salivary lactate dehydrogenase. In conclusion, differences in the values of salivary analytes can be found in fattening pigs depending on the productive phase and sex of the animals

Diseño y preparación de un laboratorio virtual de Química Analítica: Técnicas instrumentales de análisis

La reciente pandemia del COVID-19 ha supuesto un cambio excepcional y drástico de la concepción tradicional del aprendizaje, tanto para los estudiantes como para los docentes. Ante esta situación se requiere no sólo acciones que faciliten la adaptación de los estudiantes y profesores a las plataformas educativas en línea, sino también a que éstas se conviertan en auténticas herramientas para potenciar y mejorar de forma significativa el aprendizaje del alumno. El presente proyecto de Innovación Educativa y Mejora de la Calidad Docente pretende mejorar la calidad del aprendizaje de varias asignaturas de los Grados de Química e Ingeniería Química que llevan asociado un Laboratorio de Técnicas Instrumentales. Tradicionalmente esa docencia práctica ha sido presencial, pero la situación excepcional surgida con la pandemia en el curso 2019/2020, ha demostrado que disponer de unas prácticas virtualizadas es de gran ayuda para facilitar el aprendizaje de los alumnos y facilitar una transferencia del conocimiento constructivo y colaborativo. Desde hace años, el personal docente e investigador (PDI), personal de administración y servicios (PAS) y los estudiantes de la UCM, disponemos de la plataforma de enseñanza online Moodle (Campus Virtual, CV). Sin embargo, la pandemia que vivimos ha evidenciado la brecha digital en lo referente a cómo usar Moodle y, por ende, la utilización de las Tecnologías de Información y Comunicación (TICs) como facilitadoras didácticas. A pesar de nuestras limitaciones, tanto profesores como estudiantes, hemos desarrollado una enorme capacidad resiliente, lo que permitió, durante el pasado mes de mayo, la puesta en marcha de los primeros laboratorios en línea en el Departamento de Química Analítica de la UCM. Fruto de esta experiencia, así como de la situación actual de incertidumbre para el curso próximo, algunos profesores, estudiantes y PAS del departamento hemos decidido adelantarnos a un escenario futuro en el que se contemple nuevamente la impartición de Docencia Experimental en línea y solicitar el presente proyecto de Innovación Educativa y Mejora de la Calidad Docente