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Disease Risk Analysis in Wildlife Health Studies

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... The number of activated mammae/functional teats may have acted as a selective constraint in litter size of wild mammals (Korhonen, 1992). Thus, teat functionality is an aspect that may be considered in domestication of new species (Deem, 2012). Within these species, the agouti (Dasyprocta leporina) (Linnaeus, 1758) is highly prized for its meat and one of the most consumed game species in Neotropical countries (Cummins et al., 2015;Robinson and Redford, 1991). ...
... The agouti is a rodent of an average weight of 4.5 kg. The female agouti has eight mammae, two pairs in the thoracic region and two pairs in the abdominal region (Baas et al., 1976;Deem, 2012). It is a non-seasonal breeder (Baas et al., 1976;Campos et al., 2015;Guimarães et al., 2011;Singh et al., 2014) and under captive conditions, when receiving an abundance of food with a high plane of nutrition may produce larger litters (Singh and Garcia, 2015). ...
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The red-rumped agouti (Dasyprocta leporina) produces precocial young and is the most hunted and farmed game species in several Neotropical countries. An understanding of the reproductive biology, including the relationship between litter size and teat functionality is crucial for conservation management of this animal. In precocial mammals, as the red-rumped agouti, maintaining maternal contact to learn foraging patterns may be more important than the energy demands and nutritional constraints during lactation and suckling may not play important roles when compared to altricial mammals. Therefore, in this study we evaluated the relationship between mammary functionality with litter size, litter birth weight, and parturition number in captive red-rumped agouti. Functionality was assessed by manual palpation of teats from un-sedated females (N=43). We compared the average birth weight of all newborns, male newborns and female newborns among agoutis with different litter sizes and different parturitions by one way ANOVA’s, while Pearson’s Chi-squared tests were used to detect relationships between teat functionality, litter size, and parturition number. Parturition number had no effect on the mean birth weight of all young (F0.822, P > 0.05), male young (F0.80, P > 0.05) or female young (F0.66, P > 0.05) in the litters. We found (i) no significant correlations (P > 0.05) between teat functionality and litter size and (ii) no significant correlations (P > 0.05) between teat functionality and parturition number. This suggests that whilst all teat pairs were functional, functionality was a poor indicator of litter size; suggesting that female agouti young may not have a high dependency on maternal nutrition; an possible evolutionary strategy resulting in large wild populations; hence its popularity as a game species.
... stress, malnutrition, aging, comorbidity). Captive-breeding programs and wildlife translocation, while successful to prevent extinctions under some circumstances, may also facilitate the spread of microorganisms and disease if animals are translocated without com-prehensive risk analyses and proper veterinary advice (Deem, 2012;Hunter et al., 2019;Kock et al., 2010;Sainsbury & Vaughan-Higgins, 2012 Based on our results, we obtained more positive herpesvirus diagnoses from oral swabs than from ocular swabs in Galapagos tortoises; therefore, we suggest standardising the methodology to conduct long term tortoise surveillance of herpesvirus and adenovirus based on oral and cloacal swabs, respectively, and for using either PCR or qPCR protocols. We suggest the use of both adenovirus consensus primers and the specific primers described within this work when working with Galapagos tortoise samples, as specific primers may produce cleaner sequences and less false positive results than consensus primers. ...
Article
Emerging infectious diseases (EIDs) have been reported as causes of morbidity and mortality in free-living animal populations, including turtles and tortoises, and they have even resulted in species extinctions, with human activities contributing to the spread of many of these diseases. In the Galapagos, giant tortoises are endangered due to habitat change, invasive species, and other human impacts; however, the impact of EIDs on Galapagos tortoise conservation remains understudied. To fulfil this gap, we conducted health assessments of five tortoise species from the islands of Santa Cruz, Isabela, and Española. We performed health evaluations of 454 animals and PCR testing for pathogens known to be relevant in other tortoise species. We identified two novel sequences of adenoviruses and four of herpesviruses. Based on alignments of the DNA polymerase gene and maximum likelihood phylogenetic analyses, we found both novel adenoviruses to be most closely related to red footed tortoise adenovirus 2 by nucleotide sequence and red footed tortoise adenovirus 1 based on amino acid sequence. Three of the herpesvirus sequences translated into the same deduced amino acid sequence; therefore, they may be considered the same viral species, closely related to terrapene herpesvirus 2. The fourth herpesvirus sequence was highly divergent from any sequence previously detected and is related to an eagle owl herpesvirus based on nucleotide sequence and to loggerhead oro-cutaneous herpesvirus based on amino acids. These novel viruses seem to be pathogenic for giant tortoises under specific conditions (e.g., stress). Continued screening is crucial to determine if these viruses play a role in tortoise fitness, morbidity, and survival. This information allows us to provide recommendations to the Galapagos National Park Directorate and other institutions to improve the management of these unique species both in Galapagos and globally, and for tortoise reintroduction plans throughout the archipelago. This article is protected by copyright. All rights reserved
... Greg is the author of over 100 popular and scientific articles about invertebrates, fishes, amphibians and reptiles and speaks locally, nationally and internationally on these subjects. He's also authored or co-authored 25 book chapters related to veterinary medicine of the above-mentioned taxonomic groups and edited or co-edited four veterinary textbooks: Self Assessment Colour Review of Ornamental Fish (Manson Publishing and ISU Press, 1998) (Manson Publishing, 2008), and the multiple award winning Invertebrate Medicine (WileyBlackwell Publishing, 2006;2012). ...
Technical Report
Durante los días 5–9 de diciembre de 2016, el taller para desarrollar un Plan de Salud de la Vida Silvestre de Galápagos se llevó a cabo en Puerto Ayora, Galápagos. Al taller asistieron 43 participantes representantes de organizaciones estatales en Ecuador (Agencia de Regulacióny Control de la Bioseguridad y Cuarentena para Galápagos, Dirección del Parque Nacional Galápagos, Instituto Nacional de Biologíay Ministerio de Agricultura, Ganadería, Acuacultura y Pesca); universidades tanto del Ecuador (Escuela Superior Politécnica del Litoral –Facultad de Ciencias de la Vida, Universidad Central del Ecuador, y Universidad San Francisco de Quito) como de Estados Unidos (Colorado State University; North Carolina State University College of Veterinary Medicine; University of California, Davis School of Veterinary Medicine; and College of Veterinary Medicine, University of Minnesota); funcionarios/as de organizaciones de conservación no gubernamentales con base en las Galápagos (Fundación Charles Darwin, Island Conservation, Galápagos Conservancy,Sea Shepherd, y WILDAID) así como otras organizaciones internacionales (Houston Zoo,San Diego Zoo Global, San Diego Zoo, Wildlife Conservation Society, Zoological Society of London y Fundación Pro Zoológicos). La Visión del Plan de Salud para los próximos 25 años es la siguiente: “Un impacto antropogénico menor y decreciente habilita ecosistemas funcionales y resilientes que sostienen poblaciones silvestres saludables, en equilibrio con sus parásitos naturales, y cumplen con sus roles ecológicos.” Definimos parásitos en el sentido ecológico amplio, incluyendo virus, bacterias, hongos, protozoos, helmintos, artrópodos, y anélidos que tienen un ciclo de vida parasitario. Las actividades del taller siguieron los procesos de trabajo de CBSG, donde los expertos ensalud de vida silvestre conformaron seis gruposde trabajo para analizar la situación actual y recomendaron prioriades de salud de las especiesnativas de Galápagos, especies domésticas ysilvestres, y sus ecosistemas. Estos grupos fueron los siguientes: Reptiles Endémicos de Galápagos Aves Endémicas de Galápagos Mamíferos Endémicos de Galápagos Especies Introducidas e Invasoras en Galápagos Animales Domésticos Protocolos y Recopilación de Datos cuando se Manipulan Animales Silvestres
Chapter
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