The implications of climate change for Veterinary Services.

Climate change due to increasing greenhouse gas (GHG) emissions is one of the most pressing issues facing society on a global scale. The growth of GHG emissions between 2000 and 2010 was higher than in each of the previous three decades, and each of the past four decades has been successively warmer than any preceding decades since 1850. Continued GHG emissions will cause further warming and changes in the climate system. Climate change affects livestock production in multiple ways, both directly and indirectly. Many of the impacts on the livestock sector result from increasing frequency and magnitude of weather and climate extremes such as droughts, flash floods, untimely rains, frost, hail and severe storms. This article describes some of the most vulnerable disaster communities in Asia, Africa, Australia, Europe and South America. It then describes the importance of meteorological information provided by national Meteorological and Hydrological Services to help Veterinary Services support sustainable management of livestock in vulnerable pastoral communities.

Le changement climatique affecte l'intégralité du champ vétérinaire. Par conséquent, les Services vétérinaires doivent inscrire le changement climatique sur la liste des priorités relevant de leur responsabilité. Certes, les objectifs liés à la prévention des maladies, au maintien de la productivité et à la protection durable de systèmes sains restent inchangés, mais la structure et la portée des Services vétérinaires doivent être repensées. Le changement climatique va avoir des impacts directs et indirects sur les déterminants sanitaires qui relèvent du monde animal, sous des formes multiples et interdépendantes et à diverses échelles. Les Services vétérinaires doivent envisager le spectre entier de ces déterminants sanitaires s'ils veulent à la fois traiter les problématiques préexistantes dont l'aggravation sous l'effet du changement climatique est attendue et se préparer à faire face à d'autres menaces encore inconnues. Les animaux vont subir l'impact du changement climatique sous des aspects multiples qui parfois interagissent entre eux : modification de la structure des maladies infectieuses, exposition accrue à la chaleur, aux polluants et aux conditions climatiques extrêmes, accès perturbé aux ressources naturelles vitales au quotidien, modifications de l'écologie animale, de la sociobiologie et de la dynamique des populations. Afin de répondre aux attentes d'une action intégrée couvrant la totalité du champ vétérinaire, les Services vétérinaires doivent : a) assurer des services visant à atténuer les impacts ; b) réduire la vulnérabilité des populations afin de limiter ces impacts ; c) accroître la résilience des populations en vue d'éviter les impacts ; et d) traiter les risques liés au changement climatique à leur source. Il sera indispensable de mettre en place un système de renseignement sanitaire associant la surveillance des dangers et la connaissance des populations (pour prendre en compte leurs vulnérabilités) afin de procéder à une allocation des ressources adaptée. Plutôt que de se centrer sur la seule gestion du risque, les programmes devront également miser sur le renforcement des capacités pour des populations animales et des systèmes de santé animale sains et résilients. Une approche axée sur les changements transformatifs est nécessaire pour que les Services vétérinaires puissent relever les défis interconnectés que représentent le développement durable, le changement climatique et la perte de biodiversité. Cela nécessitera des partenariats et des modèles de gouvernance capables de partager et d'intégrer les connaissances et la compréhension du changement au sein des systèmes socio-écologiques, à l'échelle tant mondiale que locale.

El cambio climático afecta a la totalidad del ámbito veterinario. De ahí la necesidad de que los Servicios Veterinarios lo incluyan dentro de sus áreas de responsabilidad. Aunque los objetivos de prevenir enfermedades, mantener la productividad y preservar sistemas sanos seguirán vigentes, la forma y el alcance de los Servicios Veterinarios deberán cambiar. El cambio climático repercutirá directa e indirectamente en los determinantes de la salud animal a diversas escalas y por múltiples vías interconectadas. Para poder responder a problemas preexistentes que previsiblemente se agravarán con el cambio climático y a la vez prepararse para amenazas imprevistas, los Servicios Veterinarios deberán poder trabajar en todo el espectro de los determinantes de la salud. Hay varios mecanismos, a menudo interdependientes, a través de los cuales los efectos del cambio climático se dejarán sentir en los animales, en particular la evolución de las características de enfermedades infecciosas, la mayor exposición a altas temperaturas, los contaminantes y fenómenos meteorológicos extremos, la modificación del acceso a recursos naturales necesarios para vivir y la transformación de la ecología y sociobiología animales y las dinámicas de población. Para responder a lo que se espera de ellos y de su trabajo en todos los ámbitos de la veterinaria, los Servicios Veterinarios deben: a) proporcionar servicios destinados a atenuar las consecuencias; b) reducir la vulnerabilidad de las poblaciones para aminorar el peso de esas consecuencias; c) mejorar la resiliencia de las poblaciones para evitar las consecuencias; y d) conjurar en su origen los riesgos derivados del cambio climático. Para asignar los recursos de forma adaptada y reactiva se precisarán servicios de información zoosanitaria que combinen la vigilancia de los factores de peligro y la observación de las poblaciones (a fin de determinar su vulnerabilidad). Será necesario que los programas, en lugar de girar únicamente en torno a la gestión de riesgos, incluyan también la adquisición de capacidad en pro de sistemas de sanidad animal y poblaciones animales saludables y resilientes. Harán falta cambios transformadores para que los Servicios Veterinarios estén en condiciones de responder a los problemas interconectados del desarrollo sostenible, el cambio climático y la pérdida de diversidad biológica, lo que su vez requerirá alianzas y modelos de gobernanza que sirvan para compartir e integrar el conocimiento y la comprensión de los cambios que experimentan los sistemas socioecológicos a escala tanto mundial como local.

Changes in thyroid function of nestling tree swallows (Tachycineta bicolor) in relation to polycyclic aromatic compounds and other environmental stressors in the Athabasca Oil Sands Region.

In the Canadian Athabasca Oil Sands Region (AOSR), nestling tree swallows (Tachycineta bicolor) raised near mining-related activities accumulated greater concentrations of polycyclic aromatic compounds (PACs) that contributed to their poorer condition, growth, and reproductive success. Here, we report changes in thyroid function of the same 14 day old (do) nestlings (N ≤ 68) at these mining-related sites (OS1, OS2) compared to reference nestlings (REF1), and in relation to multiple environmental stressors that influence avian thyroid function. Thyroid function was compromised for OS1 nestlings but generally comparable between OS2 and REF1 chicks. In 2012, circulating total triiodothyronine (TT3) and thyroxine (TT4) were similar among all nestlings. The OS1 chicks had more active thyroid glands based on histological endpoints. Hepatic T4 outer-ring deiodinase (T4-ORD) activity was suppressed in OS1 and OS2 chicks. Despite inter-annual differences, OS1 chicks continued experiencing compromised thyroid function with significantly higher circulating TT4 and more active thyroid glands in 2013. The OS2 chicks had less active thyroid glands, which conceivably contributed to their suppressed growth (previously reported) relative to the heavier OS1 nestlings with more active thyroid glands. Thyroid gland activity was more influenced by the chicks' accumulation of (muscle), than exposure (feces) to naphthalene, C2-naphthalenes, and C1-fluorenes. Of four major volatile organic contaminants, sulfur dioxide (SO2) primarily influenced thyroid gland activity and structure, supporting previous findings with captive birds. When collectively considering environmental-thyroidal stressors, chicks had a greater thyroidal response when they experienced colder temperatures, accumulated more C2-naphthalenes, and consumed aquatic-emerging insects with higher PAC burdens than terrestrial insects (carbon (δ13C)). We hypothesize that the more active thyroid glands and higher circulating TT4 of the OS1 chicks supported their growth and survival despite having the highest PAC burdens, whereas the lack of thyroid response in the OS2 chicks combined with high PAC burdens, contributed to their smaller size, poorer condition and poorer survival.

Reproductive and developmental changes in tree swallows (Tachycineta bicolor) are influenced by multiple stressors, including polycyclic aromatic compounds, in the Athabasca Oil Sands.

Mining in the Athabasca Oil Sands Region (AOSR) has contributed extensively to increased exposure of wildlife to naturally occurring polycyclic aromatic compounds (PACs), yet little is known about the toxicity of PACs to wildlife in this region. We identified reproductive and developmental changes in tree swallows (Tachycineta bicolor) breeding in close proximity to mining-related activities in the AOSR, and determined these changes in relation to the birds' exposure and accumulation of 41 PACs (parent-, alkylated-PAHs), dibenzothiophenes (DBTs; previously published), diet (carbon (δ13C), nitrogen (δ15N)), volatile organic compounds, and weather variables. Tree swallow pairs (N = 43) were compared among mining-related (OS1, OS2) and reference (REF1, REF2) sites. At OS2, clutch initiation was slightly advanced (2012) but reproductive success (65%) was much lower than at the other sites (≥ 79%). Fledgling production by each pair was influenced by the timing of clutch initiation (years combined); in a highly inclement brood rearing period (2013), additional influences included the nestlings' exposure to ΣDBTs, accumulation of C1-naphthalene, the trophic position of the prey in their diet (δ15N), and record-breaking rainfall. Nestlings at OS2 were significantly lighter at day (d) 9 and d14, and in poorer body condition (d9). Nestling body mass was influenced by multiple stressors that varied by site: mass of younger nestlings (d9) was related to dietary source (δ13C; e.g., wetlands, terrestrial fields), exposure and/or accumulation of C1-phenanthrenes, C2-fluorenes, Σalkyl-PAHs and ΣDBTs, while for older nestlings (d14), body mass was related to sex, hatch date and/or rainfall during brood rearing. The swallows' exposure and accumulation of parent-PACs, alkyl-PACs and DBTs, the timing of hatching, their diet and exposure to highly inclement rains, contributed to their reproductive and developmental changes.

Survey of influenza A viruses circulating in wild birds in Canada 2005 to 2007.

A multi-agency, Canada-wide survey of influenza A viruses circulating in wild birds, coordinated by the Canadian Cooperative Wildlife Health Centre, was begun in the summer of 2005. Cloacal swab specimens collected from young-of-year ducks were screened for the presence of influenza A nucleic acids by quantitative, real-time reverse transcription-polymerase chain reaction (RRT-PCR). Specimens that produced positive results underwent further testing for H5 and H7 gene sequences and virus isolation. In addition to live bird sampling, dead bird surveillance based on RRT-PCR was also carried out in 2006 and 2007. The prevalence of influenza A viruses varied depending on species, region of the country, and the year of sampling, but generally ranged from 20% to 50%. All HA subtypes, with the exception of H14 and H15, and all NA subtypes were identified. The three most common HA subtypes were H3, H4, and H5, while N2, N6, and N8 were the three most common NA subtypes. H4N6, H3N2, and H3N8 were the three most common HA-NA combinations. The prevalence of H5 and H7 subtype viruses appears to have a cyclical nature.