UNIVERSIDADE DE LISBOA Faculdade de Medicina Veterinária PARETIC SYNDROME IN GULLS (LARIDAE) IN THE SOUTH OF PORTUGAL SUSANA PATRÍCIA VELOSO SOARES CONSTITUIÇÃO DO JÚRI ORIENTADOR Dr. Hugo Alexandre Romão de Castro Lopes Doutor Jorge Manuel de Jesus Correia Doutora Anabela de Sousa Santos da Silva CO-ORIENTADOR Moreira Dr. Hugo Alexandre Romão de Castro Lopes Doutor Luís Manuel Madeira de Carvalho 2014 LISBOA UNIVERSIDADE DE LISBOA Faculdade de Medicina Veterinária PARETIC SYNDROME IN GULLS (LARIDAE) IN THE SOUTH OF PORTUGAL SUSANA PATRÍCIA VELOSO SOARES DISSERTAÇÃO DE MESTRADO INTEGRADO EM MEDICINA VETERINÁRIA CONSTITUIÇÃO DO JÚRI ORIENTADOR Dr. Hugo Alexandre Romão de Castro Lopes Doutor Jorge Manuel de Jesus Correia Doutora Anabela de Sousa Santos da Silva CO-ORIENTADOR Moreira Dr. Hugo Alexandre Romão de Castro Lopes Doutor Luís Manuel Madeira de Carvalho 2014 LISBOA Original “- Estou a voar! Zorbas! Sei voar! – grasnava ela, eufórica, lá da vastidão do céu cinzento. O humano acariciou o lombo do gato. - Bem, gato, conseguimos – disse suspirando. - Sim, à beira do vazio compreendeu o mais importante – miou Zorbas. - Ah, sim? E o que é que ela compreendeu? – perguntou o humano. - Que só voa quem se atreve a fazê-lo – miou Zorbas.” Luis Sepúlveda (1996)* Dedico este trabalho a todos os que se atrevem, mas acima de tudo, a todos aqueles que acreditam nos primeiros. Dedico-o a ti, Mãe. *Sepúlveda, L. (1996). História de uma gaivota e do gato que a ensinou a voar. (8ªedição). Lisboa: Porto Editora. Tradução por Pedro Tamen ii iii Acknowledgements. Firstly to Dr. Hugo Lopes, my supervisor, for accepting me at RIAS, for the guidance and transmitted knowledge. I am truly grateful for opening the doors to a new world of Medicine. Secondly to Prof. Dr.Luís Madeira de Carvalho, my co-supervisor, for the knowledge, guidance, kind words, tirelessness conduct, humour and advices, that when needed were always available. To all my unofficial supervisors, for welcoming me, accompanying throughout this training period, teaching me and guiding my first incoursions into the wild. To Fábia Azevedo, for all the support and friendship. To Thijs Valkenburg, for answering all my questions and the endless patience. To my collegue Tiago Ventura, for all the moments of laughter and mischief, but also for the professional attitude and conduct. To Bruno Martins for letting me witness the success of a conservation project. To the most peculiar, but altogether fantastic group of young biologists: Ana Margarida Carvalho, Joana Lopes, André Tomás, André Pinheiro (Android) and Diogo Amaro, thank you all for the help, support and hilarious moments. To the little brothers, Yannick and Etienne Schade, for being courageous enough to assist me with the necropsies, when everyone else was giving up. To all the volunteers and passing by students that I met while in Algarve, time was short but was sufficient to learn new things and make new friends. To all the past volunteers, personnel and collaborators of RIAS, without you this paper wouldn´t exist. A especially thank you to Dr.Carla Ferreira for believing in the need to develop this theme and for all the support throughout its development. To Patricia Medina, for sharing the same attitude, determination and crave to solve this mystery. To Cátia Santos, for the exchange of data, knowledge and insightful opinions. To all the ringers, birdwatchers and bird lovers, for sharing information and concerns. Now I know that there are more like me. To Salvador Garcia, who was the first to introduce me to the problematic of paresis and paralysis in wild birds. To all the professionals of the departments of FMV-UL, for receiving, processing and analysing the animals sent. To Professor Telmo Nunes, for the statistical guidance, suggestions, patience and above all for introducing me to new ways of thinking and new tools like GIS. To IPIMA, LNEG, SPEA and Águas do Algarve, S.A., the only institutions, of the several contacted, that promptly answered and provided all the data needed, valuable recommendations and ideas. To all my friends, far too many to mention but extremely important and will always be. Last, but not the least, to my mother for always being there, believing, challenging, loving, making everything possible. Without you I wouldn’t be here. To the rest of the family, both the ones still present and those already gone, either humans or not “humans”, for the company, the incondicional love and understanding. I am one step way from fulfilling my dream. Thank you for everything. iv v Abstract: PARETIC SYNDROME IN GULLS (LARIDAE) IN THE SOUTH OF PORTUGAL RIAS, a Portuguese wildlife rehabilitation centre located in Algarve, has been admitting a substantial high number of seagulls, since its opening in October of 2009, with consistent clinical presentations pertaining to a paretic syndrome without cues of a particular disease. This preliminary study describes the clinical signs and microbiological, parasitological, toxicological and pathologic findings of paretic gulls received between 2009 and 2012. It tries to understand if there is an association between the manifestation of this disease and the different species and age classes affected. It seeks to determine possible relations between the geographic distribution of the cases and specific potentially problematic areas or human activities. All in order to additionally determine a probable cause for this disease taking into consideration the species affected, region where the animals were rescued and diseases that could explain the findings observed like: Newcastle disease, Salmonellosis, Aspergillosis, Sarcocystosis, Botulism, Algal toxicosis, Copper/Lead/Mercury intoxication, Organophosphorus/Carbamate poisoning and Thiamine deficiency. Additionally, a treatment trial with three therapeutic protocols (activated charcoal, fluid therapy and thiamine supplementation) was attempted to evaluate their influence in the outcome of the rehabilitation process and their value as a tentative diagnostic tools. Accordingly, digital records of 780 gulls were analyzed, as well as, results of more specific diagnostic ancillary tests used in carcasses and tissue samples in the centre and submitted to the Faculty of Veterinary Medicine of the University of Lisbon. From the 780 admissions, 148 gulls (18,97%) were found to have this paretic syndrome while alive, with L.fuscus and sub-adults being probably the classes most affected (p=0,02;p=0,00005). All these gulls, upon admission, were thin and dehydrated and the most frequent clinical signs documented were: depressed mental status without loss of conscious (58,8%); diarrhoea (43,9%), flaccid cloacae (70,3%); generalized muscular weakness (48,6%), moderate muscular weakness (46,6%); posterior paresis (69,6%) and moderate paresis (71,6%). Approximately half of the 148 gulls died while in rehabilitation and gross necropsy findings of paretic gulls were also unspecific and overall inconsistent. However, a high number of these gulls including dead admissions had a thin-walled cloacae distended with diarrhoea and the intestines were also displaying compatible signs of inflammation: oedema, vascular congestion and fluid faeces (32/71). Evidences of opportunistic diseases or development of confounding ailments like probably Aspergillosis were also noted. The differences between the therapeutic protocols were irrelevant (p=0,7422) and could not diagnose this condition. No pathogenic agent (bacterial or parasitic) capable of causing this syndrome was identified in the carcasses submitted (n=9). The necropsy examination and histopathology lesions reported in the faculty were inconclusive as to the cause of the paresis. Lead and Copper levels, analyzed in 2 gulls, were below what is considered in the literature as indicative of toxic. Nevertheless, in one of the gulls submitted a liver sample was positive for the presence of an organophosphorus compound, which could be in accordance with the high association measured between the spatial distribution of the proportion of paretic cases and density of several crops per municipality (Rho>0,5;p<0,05). In this moment, the data here compiled and the results obtained are still insufficient to determine or exclude the diseases in discussion as causes of this syndrome. Inconsistent use of ancillary tests results, paucity in the knowledge of ethologic and ecologic features of these birds in this region, irregularities in the retrieval of sick birds and tourism are some of the factors that may be influencing these results and should be addressed in future investigations. Key-words: Gulls, Paresis, Infectious diseases, Natural Toxins, Heavy metal intoxication, Pesticide poisoning, Thiamine deficiency, Algarve, Portugal vi vii Resumo: SÍNDROME PARÉSICO EM GAIVOTAS (LARIDAE) NO SUL DE PORTUGAL RIAS, centro de recuperação de animais selvagens localizado no Algarve, desde a sua abertura em Outubro de 2009 tem recebido um número elevado de gaivotas com um quadro clinico consistente com paresia, sem causa conhecida. Este estudo preliminar descreve os sinais clínicos e achados microbiológicos, parasitológicos, toxicológicos e anatomo/histopatológicos de gaivotas com parésia recebidas entre 2009 e 2012. Tenta igualmente perceber se existe uma associação entre a manifestação desta doença e as diferentes classes de idade e espécies afectadas. Procura determinar relações possíveis entre a distribuição geográfica dos casos e áreas/actividades humanas especificas e potencialmente problemáticas na área em estudo.