Estrès per calor, microbiota i barrera intestinal

L'estrès tèrmic pot afectar la salut i el benestar del ramat. Degut a la dificultat de portar un control exhaustiu del confort tèrmic de l'animal, s'ha realitzat un estudi per detectar i dilucidar els efectes de l'estrès per calor analitzant els canvis en els metabòlits de l'orina de cabres en lactació. Els resultats mostren que sota condicions d'estrès per calor es produeixen canvis nocius en la composició de la microbiota intestinal, alliberant substàncies tòxiques que destrueixen la integritat de les parets de l'intestí i arribant al torrent sanguini. Aquest estudi evidencia una nova possibilitat de detecció d'estrès tèrmic de manera no invasiva i accessible, a més d'una possible extrapolació en la salut humana

Inter-Observer Repeatability of Indicators of Consciousness after Waterbath Stunning in Broiler Chickens

Waterbath stunning is intended to induce unconsciousness until death occurs due to bleeding in poultry. However, it is not always effective. For this reason, in order to protect their welfare, it is mandatory in the European Union that the state of consciousness of broiler chickens is monitored at the exit of the waterbath, and that they do not regain consciousness before death. Ineffectively stunned birds can be re-stunned using back-up methods to avoid unnecessary pain, stress and suffering. One of the main challenges in monitoring the state of consciousness in broiler chickens after waterbath stunning is the selection of animal-based indicators ensuring consistency among assessments. The indicators should be valid, feasible and repeatable. However, only the validity and feasibility have been reported. Thus, the main goal of this research was to assess the repeatability of the most valid and feasible indicators of the state of consciousness after waterbath stunning in broilers both before bleeding (tonic seizure, breathing, spontaneous blinking and vocalization) and during bleeding (wing flapping, breathing, spontaneous swallowing and head shaking). This study proposes a refined list of indicators that could be used to assess the consciousness of broiler chickens in commercial slaughterhouses.info:eu-repo/semantics/publishedVersio

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

Milk yield, milk composition, and milk metabolomics of dairy goats intramammary-challenged with lipopolysaccharide under heat stress conditions

Heat stress and mastitis are major economic issues in dairy production. The objective was to test whether goat's mammary gland immune response to E. coli lipopolysaccharide (LPS) could be conditioned by heat stress (HS). Changes in milk composition and milk metabolomics were evaluated after the administration of LPS in mammary glands of dairy goats under thermal-neutral (TN; n = 4; 15 to 20 °C; 40 to 45% humidity) or HS (n = 4; 35 °C day, 28 °C night; 40% humidity) conditions. Milk metabolomics were evaluated using 1H nuclear magnetic resonance spectroscopy, and multivariate analyses were carried out. Heat stress reduced feed intake and milk yield by 28 and 21%, respectively. Mammary treatment with LPS resulted in febrile response that was detectable in TN goats, but was masked by elevated body temperature due to heat load in HS goats. Additionally, LPS increased milk protein and decreased milk lactose, with more marked changes in HS goats. The recruitment of somatic cells in milk after LPS treatment was delayed by HS. Milk metabolomics revealed that citrate increased by HS, whereas choline, phosphocholine, N-acetylcarbohydrates, lactate, and ß-hydroxybutyrate could be considered as putative markers of inflammation with different pattern according to the ambient temperature (i.e. TN vs. HS). In conclusion, changes in milk somatic cells and milk metabolomics indicated that heat stress affected the mammary immune response to simulated infection, which could make dairy animals more vulnerable to mastitis

Intramuscular vs. Intradermic Needle-Free Vaccination in Piglets: Relevance for Animal Welfare Based on an Aversion Learning Test and Vocalizations

The aim of the present study was to compare intramuscular injection with a needle and intradermic needle-free vaccinations against porcine reproductive and respiratory syndrome (PRRS) in piglets at 28 days old by studying behavioral and physiological reactions. A total of 72 piglets divided into 2 sex-balanced batches were assessed. Within each batch, the piglets were divided into three treatments, which were Hipradermic (0.2 ml of UNISTRAIN® PRRS vaccine administered with an intradermic needle-free device), Intramuscular (IM, 2.0 ml of vaccine), and Control (not vaccinated). Before the vaccination, the piglets were trained to cross a 4-m-long raceway to perform an aversion learning test. The day of vaccination, the time taken to cross the raceway was registered for each piglet at different times: prior to the vaccination and 10 min, 2, 24, 48, and 72 h after the vaccination, to measure variations in these times as signs of aversion to the vaccination process. Vocalizations, as potential signs of pain, were recorded as well at the end of this raceway to analyze their frequency (Hz), duration, and level of pressure (dB) at the moment of vaccination. Salivary cortisol, as a sign of the HPA-axis activity, was assessed 10 min after the vaccination. In addition, activity budgets, local reaction to the vaccine, and serological titer were also considered in the study. Ten minutes after the vaccination, the IM piglets took longer (p < 0.001) to cross the raceway than did the Hipradermic and Control piglets. Vocalizations were significantly different between the three treatments: the Control piglets produced vocalizations with the lowest frequency (p < 0.001) and level of pressure (p < 0.001), and IM with the highest, with Hipradermic in a significant intermediate position (p < 0.001). Accordingly, the day of the vaccination, IM and Hipradermic animals were lying on the side of the vaccine administration a greater proportion of time than were the Control piglets (10, 11, and 6%, respectively; p = 0.027). Salivary cortisol was not significantly different between treatments. The serum titer of antibodies against the PRRS was higher (p < 0.001) in both vaccinated treatments in comparison to the Control piglets. It is concluded that the Hipradermic needle-free vaccination may result in a less aversive experience in piglets than did intramuscular vaccination.info:eu-repo/semantics/publishedVersio

The application of omics in ruminant production: a review in the tropical and sub-tropical animal production context

The demand for animal products (e.g. dairy and beef) in tropical regions is expected to increase in parallel with the public demand for sustainable practices, due to factors such as population growth and climate change. The necessity to increase animal production output must be achieved with better management and production technologies. For this to happen, novel research methodologies, animal selection and postgenomic tools play a pivotal role. Indeed, improving breeder selection programs, the quality of meat and dairy products as well as animal health will contribute to higher sustainability and productivity. This would surely benefit regions where resource quality and quantity are increasingly unstable, and research is still very incipient, which is the case of many regions in the tropics. The purpose of this review is to demonstrate how omics-based approaches play a major role in animal science, particularly concerning ruminant production systems and research associated to the tropics and developing countriesinfo:eu-repo/semantics/acceptedVersio

The use of omic-methodologies in the assessment of heat-stressed lactating dairy goats

L’estrés per calor (EC) genera pèrdues significatives en l’industria lletera caprina quan l’índex de temperatura-humitat (THI) és > 75. Les tecnologies ‘òmiques’ ofereixen una perspectiva holística de com les cabres combaten l’EC i poden permetre trobar biomarcadors. Amb aquest objectiu, es van portar a terme 3 experiments (Exp.) utilitzant cabres lleteres Murciano-Granadines i una càmbra climàtica amb caixes metabòliques. Les cabres lleteres (n = 32) es van alimentar amb una ració total mesclada i es van munyir ⨯1 diàriament sota dos condicions climàtiques. Aquestes foren: TN (termo-neutralitat, THI = 59-65) i EC (dia, THI = 86; nit, THI = 77) amb fotoperíode (llum-foscor) constant (12-12 h). Es van controlar a diari diferents variables fisiològiques i productives, setmanalment la composició de la llet i a l’inici i al final de tots els períodes Exp, el pes corporal. En l’Exp.1, es van estudiar els canvis transcriptòmics en sang de 2 grups de 4 cabres (n = 8) sota TN o EC durant 35 dies. Els microarrays en mostres de sang van revelar que l’EC va augmentar l’expressió de 55 gens i en va reduir la de 88 gens. L’anàlisi Dynamic Impact Approach va indicar 31 rutes biològiques afectades per EC. Els efectes van ésser negatius per a la migració transendotelial dels leucòcits, l’adhesió cel·lular, el llinatge de cèl·lules hematopoiètiques, i la senyalització de Ca i PPAR, mentre que es va activar el metabolisme dels nucleòtids. En conclusió, l’EC va afectar negativament a la producció de llet i va alterar la funcionalitat de les cèl·lules immunitàries, fet que podria resultar en un sistema immunitari amb menor capacitat per combatre malalties. En l’Exp.2, es van avaluar candidats de biomarcadors d’EC en orina mitjançant 1H RMN (Resonància Magnètica Nuclear de protons). Les cabres (n = 16) es van sotmetre a les condicions de TN i EC segons un disseny crossover durant 35 d. Es va emprar un anàlisi de mínims quadrats discriminatoris parcials (PLS-DA) amb validació creuada que va permetre separar els grups TN i EC. Els metabòlits discriminants entre grups van ser derivats tòxics de la fenilalanina (Phe) (OH-fenilacetat, OH-fenilacetilglicina, fenilglioxilat i hipurat) que van augmentar en EC, respecte a TN. Una major excreció d’aquests compostos en orina va indicar que l’EC indueix un sobrecreixement de la microbiota gastrointestinal nociva segrestant els aminoàcids aromàtics de la ració. En consequència, l’EC hauria de disminuir la síntesi de neurotransmissors i hormones tiroidees, abaixant el rendiment i la composició de la llet. En conclusió, la minvada lletera de les cabres EC es va reflexar en el seu metaboloma per la presència de compostos tòxics derivats del tracte gastrointestinal en l’orina. Es van identificar els derivats de Phe i l’hipurat com biomarcadores d’EC en orina de cabres lleteres. En l’Exp.3, les cabres lleteres (n = 8) es van sotmetre a les condicions de TN i EC durant 15 dies i es van avaluar biomarcadors candidats en llet mitjançant 1H RMN. El dia 12, se les va exposar a lipopolisacàrid d’E. coli (LPS) o salí (CON) en una de les mamelles i es varen prendre mostres de llet a les 0, 4, 6, 12 y 24 h. El citrat en llet va augmentar en EC indicant un canvi en la funció mitocondrial dels macròfags (i.e. transport de citrat de la mitocòndria al citosol para produir mediadors inflamatoris). El metaboloma en llet de les mamelles TN-LPS va quedar menys afectat i va recuperar el seu nivell basal en un període més curt que en les mamelles EC-LPS. Els metabòlits discriminants van ésser la colina, els N-acetil-carbohidrats, L-lactat, ß-hidroxibutirat i la fosfocolina. Per tant, el perfil metabolòmic de la llet es va veure molt afectat per les condicions ambientals i de salut de la mamella. El citrat i la colina van indicar l’aparició d’estadis oxidatius e inflamatoris en la glàndula mamària sota EC o LPS, respectivament, pel que es proposen com a biomarcadors en llet.Heat stress (HS) causes significant losses in the dairy goat industry when temperature-humidity index (THI) is >75. ‘Omic’ technologies offer a holistic approach to figure out how goats cope with HS and to find biomarkers. With this aim, 3 experiments (Exp.) were carried out using Murciano-Granadina dairy goats and a climatic chamber with metabolic boxes. Lactating does (n = 32) were fed a total mixed ration, freely watered and milked ⨯1 daily under different climatic conditions. They were: TN (thermal neutral, THI = 59-65) and HS (day, THI = 86; night, THI = 77). Photoperiod (light-dark) was constant (12-12 h). Physiological and performance traits were recorded daily, milk composition sampled weekly and BW at the start and the end of each Exp. period. In Exp.1, changes in blood transcriptome of 2 groups of 4 does (n = 8), under TN or HS were studied for 35 d. In addition to performance impairment, microarrays of blood samples at d 35, revealed that HS up-regulated 55 genes and down-regulated 88. Dynamic Impact Approach analysis showed 31 biological pathways affected by HS. Effects were negative in these related with leukocyte transendothelial migration, cell adhesion, hematopoietic cell lineage, Ca and PPAR signaling, whereas were positive on those activating nucleotide metabolism. In conclusion, HS worsened milk performances and altered the functionality of immune cells, which may result in a less competent immune system for fending-off diseases. In Exp.2, HS candidate biomarkers in urine were assessed by 1H NMR (proton Nuclear Magnetic Resonance)-based metabolomics. Does (n = 16) were submitted to the TN and HS conditions in a crossover design lasting 35 d. Partial least square-discriminant analysis with cross validation were used to separate between TN and HS clusters. Discriminating metabolites were Phenilalanine (Phe) derivative toxic compounds (OH-phenylacetate, OH-phenylacetylglycine, phenylglyoxylate and hippurate), which increased in HS vs. TN does. Increased urinary excretion of these compounds indicated a harmful gastrointestinal microbiota overgrowth by HS, which sequestrated dietary aromatic amino acids. Consequently, HS does should have decreased the synthesis of neurotransmitters and thyroid hormones, impairing milk yield and composition. In conclusion, lactational impairment of HS does was reflected in their metabolome by the presence of gut-derived toxic compounds in urine. Phe derivatives and hippurate were identified as key urinary biomarkers of HS dairy goats. In Exp.3, lactating dairy goats (n = 8) were submitted to the TN and HS conditions for 15 d and milk candidate biomarkers assessed by 1H NMR. On d 12, does were challenged with E. coli lipopolysaccharide (LPS) or saline (CON) by udder-half and milk samples collected post-challenge (h 0, 4, 6, 12 and 24). Treatments were: TN (CON and LPS) and HS (CON and LPS). Milk citrate increased in HS revealing a shift in macrophages’ function (i.e., transporting mitochondrial citrate to cytosol to produce inflammatory mediators). Differences between TN and HS in response to LPS over time where observed by PLS-DA. Milk metabolome in TN-LPS udder halves was less affected and restored earlier than in HS-LPS halves. Most discriminating metabolites were choline, N-acetylcarbohydrates, L-lactate, ß-hydroxybutyrate (BHBA) and phosphocholine. Overall, milk metabolomic profiles were markedly affected by ambient and udder health conditions. Citrate and choline indicated the occurrence of oxidative and inflammatory stages in HS and LPS stressed mammary glands, respectively, and were proposed as key biomarkers in milk

Milk yield, milk composition, and milk metabolomics of dairy goats intramammary-challenged with lipopolysaccharide under heat stress conditions

Heat stress and mastitis are major economic issues in dairy production. The objective was to test whether goat’s mammary gland immune response to E. coli lipopolysaccharide (LPS) could be conditioned by heat stress (HS). Changes in milk composition and milk metabolomics were evaluated after the administration of LPS in mammary glands of dairy goats under thermal-neutral (TN; n=¿4; 15 to 20¿°C; 40 to 45% humidity) or HS (n¿=¿4; 35¿°C day, 28¿°C night; 40% humidity) conditions. Milk metabolomics were evaluated using 1H nuclear magnetic resonance spectroscopy, and multivariate analyses were carried outThis work is part of 2 research projects funded by the Spanish Ministry of Economy and Competitiveness (AGL2013-44061-R and RTA205-00035-C03-02). Alexandra Contreras-Jodar received a scholarship from the Spanish Ministry of Economy and Competitiveness (Reference BES-2012-052602). Te authors are also grateful to the team of SGCE (Servei de Granges i Camps Experimentals) of the UAB for the care of the animals. We also thank the Servei de Ressonància Magnètica Nuclear,Postprint (published version