Comportamiento social y de alimentación del rebeco pirenaico (Rupicapra Pyrenaica Pyrenaica)

Consultable des del TDXTítol obtingut de la portada digitalitzadaEste trabajo se divide en cinco estudios, cuyos objetivos son estudiar la selección del hábitat del rebeco pirenaico (Rupicapra pyrenaica pyrenaica), la posible segregación sexual de la especie, el comportamiento social y de alimentación dentro de las manadas, cambios estacionales en la concentración fecal de metabolitos del cortisol como indicadores de estrés y parámetros fermentativos de la población microbiana ruminal de un rebeco. Este estudio se llevó a cabo en la Sierra del Cadí desde enero del 2001 a julio del 2004. Los rebecos se observaban recorriendo la zona de estudio a pie, clasificando a los individuos por edades y sexo. Se tenían en cuenta aspectos como la altitud, cobertura vegetal, orientación de la pendiente y distancia a un terreno de escape. Se obtuvieron muestras de pasto y heces de 4 zonas desde el 2001 al 2003 para estudiar el nitrógeno del pasto (NP), como indicador de la calidad del forraje, y el nitrógeno fecal (NF), como indicador de la calidad de la dieta. Las heces fueron utilizadas también para analizar metabólitos de cortisol. Para estudiar la conducta social y de alimentación dentro de los grupos se hizo el seguimiento de un animal durante 10 minutos, considerándose su posición central o periférica y anotando diversas actividades en fracciones de 5 segundos. Se utilizaron 6 fermentadores de doble flujo continuo durante un periodo experimental de 10 días para comparar digestibilidades de materia seca (MS) y fibra, el perfil de fermentación y el metabolismo del nitrógeno de poblaciones bacterianas ruminales procedentes de rebeco y de vaca (Bos taurus). Los resultados globales mostraron una clara segregación sexual, con los machos seleccionando por zonas con pino y matorral a media altura y las hembras por zonas de prado, con migraciones altitudinales más evidentes que en los machos. Debido al patrón de migración altitudinal de las hembras, los animales segregados estaban siempre en zonas con valores similares de NP. Una mala correlación entre NP y NF confirmó el carácter altamente selectivo del rebeco. El nivel de vigilancia fue más alto para los animales en el centro de la manada que en la periferia, sin efecto del tamaño del grupo o edad del animal. Machos y hembras mostraron un alto grado de desincronización de actividades en los grupos mixtos. Los metabolitos de cortisol en heces (MCH) mostraron un claro patrón estacional, siendo más altos en invierno y con cierta correlación con las temperaturas mínimas medias mensuales y el NF. No hubo diferencias en las digestibilidades de la MS y fibras, así como en la concentración total de ácidos grasos volátiles entre los inóculos de rebeco y vaca. No obstante, la proporción de propionato y nitrógeno amoniacal fue más alta en el rebeco, mientras que el butirato y la síntesis de proteína bacteriana fue más alta en la vaca. Así pues y en conclusión, los resultados de este estudio coinciden con las premisas propuestas por la hipótesis de las estrategias reproductivas para explicar la segregación sexual en ungulados, con un pico de segregación sexual en verano, cuando aparentemente las crías son más susceptibles a la depredación. No obstante, la calidad de la dieta debería de ser reconsiderada como factor involucrado en este fenómeno para especies con alta capacidad de selección, como es el caso del rebeco. La hipótesis del tamaño corporal-dimorfismo sexual fue rehusada de acuerdo con los resultados obtenidos, y otras hipótesis que intentan explicar la segregación sexual en ungulados, como la de los factores sociales o la de los ritmos de actividad (activity budget), parcialmente apoyada por el comportamiento de ambos sexos en grupos mixtos, necesitan ser estudiadas con mayor profundidad. Por otro lado, el rebeco, por las diferencias mostradas en referencia a otros ungulados, aparece como una especie interesante para estudiar aspectos de comportamiento social. Desde un punto de vista de gestión, los MCH pueden ser un buen índice de estrés invernal en el rebeco y los fermentadores una herramienta útil para estudiar la función ruminal de especies salvajes. De acuerdo con los resultados obtenidos, en igualdad de condiciones, la población microbiana ruminal de un rebeco tendría una capacidad de digestión parecida a la de una vaca, pero diferirían en el perfil de fermentación, y el rebeco tendría menor síntesis de proteína bacteriana.The present work was divided in 5 main studies. The objectives were to study the habitat selection of Pyrenean chamois (Rupicapra pyrenaica pyrenaica), aspects related to a possible sexual segregation of the species, social and feeding behaviour within the herd, seasonal changes in fecal cortisol metabolites (FCM), as an indicator of stress, and fermentation parameters of a rumen microbial population of Pyrenean chamois. This study was conducted in the Cadí range, in North Eastern Spain, from January 2001 to July 2004. During foot surveys, groups of Pyrenean chamois were observed and their individuals identified by age and sex. For each group, aspects like altitude, predominant vegetation cover, slope orientation, and distance from an escape terrain were studied. Pasture and fecal samples were collected from 4 specific zones throughout the year from 2001 to 2003 to study the nitrogen content of pasture (PN), as an indicator of forage quality, and the nitrogen content of feces (FN), as an indicator of diet quality. Fecal samples were also analyzed for fecal cortisol metabolites as an indicator of stress. To study social and feeding behaviour within the herd, focal animal sampling of 10 minutes was carried out. The central or peripheral position of individuals in the herd was considered and different activities were recorded in fractions of 5 seconds. In addition, 6 dual-flow continuous culture fermenters were used in a 10-day experimental period to compare the digestibilities of dry matter (DM) and fiber, ruminal fermentation profile and nitrogen metabolism of rumen microbial population from an inoculum of chamois and cattle (Bos taurus). General results show a clear sexual segregation in the population studied, with males selecting for mid-altitudes and pine or bush areas, and females for grassland areas. A stronger seasonal altitudinal migration was observed in females than males. No differences were found in PN between the different zones occupied by chamois, due to the altitudinal migration of females during the year. A poor correlation was obtained between PN and FN due to the high selective character of Pyrenean chamois when feeding. Data recorded show a greater vigilance rate in the centre of a herd than at the periphery, with no differences in relation to group size or age of individuals. Differences were observed in activity patterns between sexes, with a low level of synchronization between males and females. Fecal cortisol metabolites (FCM) presented a clear seasonal pattern, with the highest value in winter. Correlations were obtained between FCM and both monthly mean minimum temperatures and fecal nitrogen. Comparing the fermentation activity using inocula from cattle and chamois, no differences in DM and fiber digestibilities, and total volatile fatty acids concentration (VFA) were found. The proportion of propionate and ammonia nitrogen concentration was higher in chamois than in cattle, but the proportion of butyrate and microbial protein synthesis was lower in chamois than in cattle. In conclusion, our observations were in accordance with the reproductive strategy hypothesis to explain sexual segregation in ungulates, with a peak in sexual segregation in summer, when kids are supposed to be more vulnerable to predation. However, the claim of this hypothesis that diet quality is a factor involved in sexual segregation, should be reconsidered for species with a high selective character such as Pyrenean chamois. The body-size dimorphism hypothesis was rejected to explain sexual segregation in our population. Other such as the social factors and activity budget hypotheses, partially supported by male and female behaviour in mixed herds, need to be sutdied further. Pyrenean chamois could be a good species for studing social behaviour due to differences observed with regard to other ungulates. From a management point of view, the results obtained show that cortisol metabolites in feces can be a good measure of winter stress in chamois. In addition, the dual-flow continuos culture could be a useful tool to study ruminal function in wild species. According to the results obtained in this study, the microbial population in chamois, maintained in the same ruminal conditions as in cattle, has a similar digestion capacity compared with microbial population in cattle, but with a different fermentation profile, and lower microbial protein synthesis

Stunning pigs with different gas mixtures : Aversion in pigs

The objective of this study was to assess the aversion to exposure of 90% argon, 70% N2/30% CO2 and 85% N2/15% CO 2 by volume in atmospheric air in 24 halothane-free slaughter-weight pigs using aversion learning techniques and behavioural studies in an experimental slaughterhouse. Pigs were subjected to the treatments individually during 2 separate trials of 12 animals each. The time of exposure to the gases was 46 and 32 s, respectively. When the pit contained any of the 3 gas mixtures, the time taken to cross the raceway and enter the cradle (TCREC) increased compared with the training sessions (atmospheric air). The incidence of pigs showing retreat and escape attempts and gasps and the number of times that this behaviour was performed was lower in 90% argon than in the gas mixtures with N2 and CO2. On the other hand, the time to loss of posture was lower with 70% N2/30% CO2 than with argon. The second exposure to all gas mixtures was more aversive than the first and the loss of posture also occurred earlier in the second exposure. In conclusion, pigs showed more aversion to gas mixtures with N2 and either 15% or 30% CO 2 by volume than 90% argon by volume

Diferències ruminals entre l'isard i la vaca

En el procés digestiu dels remugants intervé una complexe població de microorganismes que degrada la matèria vegetal i possibilita obtenir energia útil per a l'animal hoste. L'isard i la vaca, tot i ser tots dos remugants han d'utilitzar el seu sistema gastrointestinal de manera diferent. Investigadors de la UAB han comparat el funcionament de les poblacions bacterianes ruminals d'ambdues espècies. Han arribat a la conclusió que els bacteris de l'isard i de la vaca poden degradar la dieta en les mateixes condicions. No obstant això, els perfils de fermentació ruminal són diferents suggerint que existeixen diferències entre les poblacions bacterianes predominants d'ambdues espècies.En el proceso digestivo de los rumiantes interviene una compleja población de microorganismos que degradan la materia vegetal y posibilitan obtener energía útil para el animal huésped. El rebeco y la vaca, aunque ambos son rumiantes, han de utilizar su sistema gastrointestinal de manera diferente. Investigadores de la UAB han comparado el funcionamiento de las poblaciones bacterianas ruminales de ambas especies. Han llegado a la conclusión de que las bacterias del rebeco y de la vaca pueden degradar la dieta en las mismas condiciones. No obstante, los perfiles de fermentación ruminal son diferentes, sugiriendo que existen diferencias entre las poblaciones bacterianas de ambas especies

Visió històrica de la veterinària a partir d'un text del segle XVII

Inclou la reproducció fotocopiada de l'obra Llibre dels secrets de Agricultura, casa rústica y pastoril. Per Fra Miquel Agustí. Barcelona: Esteve Liberós, 1617.Treball presentat a l'assignatura de Deontologia i Veterinària Legal (21223

A gene co-association network regulating gut microbial communities in a Duroc pig population

Background: Analyses of gut microbiome composition in livestock species have shown its potential to contribute to the regulation of complex phenotypes. However, little is known about the host genetic control over the gut microbial communities. In pigs, previous studies are based on classical "single-gene-single-trait" approaches and have evaluated the role of host genome controlling gut prokaryote and eukaryote communities separately. Results: In order to determine the ability of the host genome to control the diversity and composition of microbial communities in healthy pigs, we undertook genome-wide association studies (GWAS) for 39 microbial phenotypes that included 2 diversity indexes, and the relative abundance of 31 bacterial and six commensal protist genera in 390 pigs genotyped for 70 K SNPs. The GWAS results were processed through a 3-step analytical pipeline comprised of (1) association weight matrix; (2) regulatory impact factor; and (3) partial correlation and information theory. The inferred gene regulatory network comprised 3561 genes (within a 5 kb distance from a relevant SNP-P < 0.05) and 738,913 connections (SNP-to-SNP co-associations). Our findings highlight the complexity and polygenic nature of the pig gut microbial ecosystem. Prominent within the network were 5 regulators, PRDM15, STAT1, ssc-mir-371, SOX9 and RUNX2 which gathered 942, 607, 588, 284 and 273 connections, respectively. PRDM15 modulates the transcription of upstream regulators of WNT and MAPK-ERK signaling to safeguard naive pluripotency and regulates the production of Th1- and Th2-type immune response. The signal transducer STAT1 has long been associated with immune processes and was recently identified as a potential regulator of vaccine response to porcine reproductive and respiratory syndrome. The list of regulators was enriched for immune-related pathways, and the list of predicted targets includes candidate genes previously reported as associated with microbiota profile in pigs, mice and human, such as SLIT3, SLC39A8, NOS1, IL1R2, DAB1, TOX3, SPP1, THSD7B, ELF2, PIANP, A2ML1, and IFNAR1. Moreover, we show the existence of host-genetic variants jointly associated with the relative abundance of butyrate producer bacteria and host performance

Gut eukaryotic communities in pigs : diversity, composition and host genetics contribution

Background. The pig gut microbiome harbors thousands of species of archaea, bacteria, viruses and eukaryotes such as protists and fungi. However, since the majority of published studies have been focused on prokaryotes, little is known about the diversity, host-genetic control, and contributions to host performance of the gut eukaryotic counterparts. Here we report the first study that aims at characterizing the diversity and composition of gut commensal eukaryotes in pigs, exploring their putative control by host genetics, and analyzing their association with piglets body weight. Results. Fungi and protists from the faeces of 514 healthy Duroc pigs of two sexes and two different ages were characterized by 18S and ITS ribosomal RNA gene sequencing. The pig gut mycobiota was dominated by yeasts, with a high prevalence and abundance of Kazachstania spp. Regarding protists, representatives of four genera (Blastocystis, Neobalantidium, Tetratrichomonas and Trichomitus) were predominant in more than the 80% of the pigs. Heritabilities for the diversity and abundance of gut eukaryotic communities were estimated with the subset of 60d aged piglets (N = 390). The heritabilities of α-diversity and of the abundance of fungal and protists genera were low, ranging from 0.15 to 0.28. A genome wide association study reported genetic variants related to the fungal α-diversity and to the abundance of Blastocystis spp. Annotated candidate genes were mainly associated with immunity, gut homeostasis and metabolic processes. Additionally, we explored the association of gut commensal eukaryotes with piglet body weight. Our results pointed to a positive contribution of fungi from the Kazachstania genus, while protists displayed both positive (Blastocystis and Entamoeba) and negative (Trichomitus) associations with piglet body weight. Conclusions. Our results point towards a minor and taxa specific genetic control over the diversity and composition of the pig gut eukaryotic communities. Moreover, we provide evidences of the associations between piglets' body weight after weaning and members from the gut fungal and protist eukaryote community. Overall, this study highlights the relevance of considering, along with that of bacteria, the contribution of the gut eukaryote communities to better understand host-microbiome association and their role on pig performance, welfare and health

Leveraging host-genetics and gut microbiota to determine immunocompetence in pigs

The gut microbiota influences host performance playing a relevant role in homeostasis and function of the immune system. The aim of the present work was to identify microbial signatures linked to immunity traits and to characterize the contribution of host-genome and gut microbiota to the immunocompetence in healthy pigs. To achieve this goal, we undertook a combination of network, mixed model and microbial-wide association studies (MWAS) for 21 immunity traits and the relative abundance of gut bacterial communities in 389 pigs genotyped for 70K SNPs. The heritability (h 2 ; proportion of phenotypic variance explained by the host genetics) and microbiability (m 2 ; proportion of variance explained by the microbial composition) showed similar values for most of the analyzed immunity traits, except for both IgM and IgG in plasma that was dominated by the host genetics, and the haptoglobin in serum which was the trait with larger m 2 (0.275) compared to h 2 (0.138). Results from the MWAS suggested a polymicrobial nature of the immunocompetence in pigs and revealed associations between pigs gut microbiota composition and 15 of the analyzed traits. The lymphocytes phagocytic capacity (quantified as mean fluorescence) and the total number of monocytes in blood were the traits associated with the largest number of taxa (6 taxa). Among the associations identified by MWAS, 30% were confirmed by an information theory network approach. The strongest confirmed associations were between Fibrobacter and phagocytic capacity of lymphocytes (r = 0.37), followed by correlations between Streptococcus and the percentage of phagocytic lymphocytes (r = -0.34) and between Megasphaera and serum concentration of haptoglobin (r = 0.26). In the interaction network, Streptococcus and percentage of phagocytic lymphocytes were the keystone bacterial and immune-trait, respectively. Overall, our findings reveal an important connection between gut microbiota composition and immunity traits in pigs, and highlight the need to consider both sources of information, host genome and microbial levels, to accurately characterize immunocompetence in pigs. The online version contains supplementary material available at 10.1186/s42523-021-00138-9

Malignant infarction of the middle cerebral artery in a porcine model. A pilot study

Animal models; Central nervous system; InfarctionModels animals; Sistema nerviós central; InfartModelos animales; Sistema nervioso central; InfartoBackground and purpose Interspecies variability and poor clinical translation from rodent studies indicate that large gyrencephalic animal stroke models are urgently needed. We present a proof-of-principle study describing an alternative animal model of malignant infarction of the middle cerebral artery (MCA) in the common pig and illustrate some of its potential applications. We report on metabolic patterns, ionic profile, brain partial pressure of oxygen (PtiO2), expression of sulfonylurea receptor 1 (SUR1), and the transient receptor potential melastatin 4 (TRPM4). Methods A 5-hour ischemic infarct of the MCA territory was performed in 5 2.5-to-3-month-old female hybrid pigs (Large White x Landrace) using a frontotemporal approach. The core and penumbra areas were intraoperatively monitored to determine the metabolic and ionic profiles. To determine the infarct volume, 2,3,5-triphenyltetrazolium chloride staining and immunohistochemistry analysis was performed to determine SUR1 and TRPM4 expression. Results PtiO2 monitoring showed an abrupt reduction in values close to 0 mmHg after MCA occlusion in the core area. Hourly cerebral microdialysis showed that the infarcted tissue was characterized by reduced concentrations of glucose (0.03 mM) and pyruvate (0.003 mM) and increases in lactate levels (8.87mM), lactate-pyruvate ratio (4202), glycerol levels (588 μM), and potassium concentration (27.9 mmol/L). Immunohistochemical analysis showed increased expression of SUR1-TRPM4 channels. Conclusions The aim of the present proof-of-principle study was to document the feasibility of a large animal model of malignant MCA infarction by performing transcranial occlusion of the MCA in the common pig, as an alternative to lisencephalic animals. This model may be useful for detailed studies of cerebral ischemia mechanisms and the development of neuroprotective strategies.The Neurotraumatology and Neurosurgery Research Unit is supported by a grant from the Departament d'Universitats, Recerca i Societat de la Informació de la Generalitat de Catalunya (SGR 2014-844). This work has been supported in part by the Fondo de Investigación Sanitaria (Instituto de Salud Carlos III) with grant FIS PI11/00700, which was co-financed by the European Regional Development Fund (ERDF) and awarded to Dr. J. Sahuquillo. A. Sánchez-Guerrero is the recipient of a personal pre-doctoral grant from the Instituto de Salud Carlos III (grant number grant number FI12/00074)

Estrategias nutricionales para reducir el efecto de estrés térmico en cerdo ibérico

La elevada exposición a la temperatura ambiente puede causar importantes consecuencias en la salud y la producción de los animales. Como los cerdos tienen glándulas sudoríparas no funcionales, son más sensibles al estrés por calor que otros animales. Por esta razón, este experimento se realizó con el fin de estudiar una estrategia nutricional para aliviar el efecto del estrés por calor en los cerdos. La estrategia nutricional fue reemplazar el 5% de almidón por 5% de aceite de girasol de alto contenido oleico en la dieta ya que la grasa es una fuente importante de energía y conduce a un menor incremento de calor que los carbohidratos y las proteínas. Por lo tanto, un total de setenta y dos machos castrados cruzados (50% ibéricos - 50% Duroc) cerdos ibéricos con un promedio de 51,1 ± 0,75 Kg fueron expuestos a altas temperaturas ambientales de (30 - 320C) durante 5 horas del día y durante las otras horas, se mantuvo la temperatura a un mínimo de 25ºC. Los cerdos fueron distribuidos en tres habitaciones a razón de cuatro corrales por sala y seis animales por corral. Se aplicaron dos tratamientos basados en dos diferentes tipos de dieta: dieta control (control) y dieta alta en grasa (alternativa). Además, se utilizaron dos formas de alimentación. La mitad de los animales fueron alimentados ad-libitum y la otra mitad restringida. Las muestras para el análisis de hemograma y bioquímico se tomaron al inicio y al final del estudio y se realizó un análisis de la calidad de la carne y la canal después del sacrificio. Además, el rendimiento (consumo de alimento, peso corporal) se evaluó regularmente y el comportamiento de los cerdos se observó diariamente. Durante el período experimental, la ingesta de alimento se redujo, mientras que no hubo diferencia en la ganancia media diaria, por lo tanto, la conversión alimenticia fue menor en la dieta alternativa (alto contenido de grasa) que en la dieta de control. Los niveles de LDL, el colesterol malo, no mostraron ninguna diferencia entre las dos dietas que muestran que el aumento del contenido de la dieta en la grasa no mostró malas consecuencias en el contenido de lípidos séricos en los cerdos. Además, la alimentación de la dieta alternativa dio lugar a un mayor rendimiento de canal y contenido oleico en la grasa. Por otra parte, el comportamiento de dormir (tumbarse) y excreción además de las interacciones sociales se vieron afectados por la temperatura y diferían entre los tratamientos. En conclusión, el reemplazo del almidón por la grasa durante condiciones de alta temperatura ambiente mejoró la eficiencia de la alimentación, las características de la canal y el producto final obtenido fue más atractivo para los consumidores debido al mayor contenido en ácido oleico