Time filter

Source Type

Washington, DC, United States

Comizzoli P.,Center for Species Survival | Songsasen N.,Smithsonians National Zoological Park | Wildt D.E.,Center for Species Survival
Cancer Treatment and Research | Year: 2010

Sustaining viable populations of any wildlife species requires a combination of adequate habitat protection and a good understanding of environmental and biological factors (including reproductive mechanisms) that ensure species survival. Thousands of species are under threat of extinction due to habitat loss/degradation, over-exploitation, pollution, disease, alien species invasions and urban sprawl. This has served as incentive for intensive management of animal populations, both ex situ (in captivity) and in situ (living in nature). Assisted reproductive technologies developed for addressing human infertility and enhancing livestock production have shown encouraging promise in a few wildlife species. However, species-specific physiological variations and a lack of fundamental knowledge have limited how these tools can be used to help rapidly re-build endangered species numbers. Despite limitations, there is enormous potential in applying human-related fertility preservation strategies to wild animals, especially approaches that could assist managing or 'rescuing' the genomes of genetically valuable individuals. Indeed, one of the highest priorities in wildlife ex situ management is sustaining all existing genetic diversity to (1) preserve heterozygosity to avoid inbreeding depression and (2) ensure species integrity and the persistence of genomic adaptability to environmental changes. There are components of the rapidly emerging field of oncofertility in women that are highly compatible with preserving valuable genomes of individuals or populations of threatened wildlife. Strategies associated with ovarian tissue cryopreservation and follicle in vitro culture are especially attractive for protecting and extending fertility for wild females. Given adequate attention and more basic studies, we predict that these approaches could assist in the intensive and practical management of gene diversity in endangered species. © 2010 Springer Science+Business Media, LLC.

Rayhel L.,University of Missouri | Aitken-Palmer C.,Conservation Biology Institute | Joyner P.,Conservation Biology Institute | Cray C.,University of Miami | And 3 more authors.
Journal of Zoo and Wildlife Medicine | Year: 2015

In this retrospective study, 36 hematologic and biochemistry samples from white-naped crane (Grus vipio) were analyzed. All birds were housed at a single institution, and samples were obtained between 1990 and 2013. All cranes were healthy at the time of sample collection, and ages ranged from 1 mo to 33 yr old. Cranes below 18 mo old were considered juveniles. Comparisons were made between means for juveniles and adults and for males and females. Significant increases in adults (P < 0.05) were found in the following variables (differences shown in parentheses): packed cell volume (8.3%), mean cell volume (28 fl), monocyte percentage (3.2%), absolute monocyte count (200 × 103/ml), total solids (1.0 g/dl), albumin (0.5 g/dl), and sodium (3 mM/L). Significant decreases in adults (P < 0.05) were found in phosphorus (1.7 mg/dl), creatine phosphokinase (1,146 U/L), alkaline phosphatase (451 U/L), lactate dehydrogenase (149 U/L), and glucose (25 mg/dl). Results from adult male and female cranes were also compared; calcium levels were higher in females (4.68 mg/dl, P < 0.05). Plasma electrophoresis and radioimmunoassay for bile acids were performed on 25 banked serum or plasma samples; results from juvenile and adult samples were also compared. Significant increases in adult birds were found in total protein (1.2 g/dl, P < 0.05) and in all absolute values for all protein types; however, no difference was found when protein fractions were compared. Bile acids were found to decrease in adults (19.9 μM/L, P < 0.05). © Copyright 2015 by American Association of Zoo Veterinarians.

Janes D.E.,Harvard University | Janes D.E.,Iowa State University | Elsey R.M.,Rockefeller Wildlife Refuge | Langan E.M.,Smithsonians National Zoological Park | And 3 more authors.
Sexual Development | Year: 2013

Across amniotes, sex-determining mechanisms exhibit great variation, yet the genes that govern sexual differentiation are largely conserved. Studies of evolution of sex-determining and sex-differentiating genes require an exhaustive characterization of functions of those genes such as FOXL2 and FGF9. FOXL2 is associated with ovarian development, and FGF9 is known to play a role in testicular organogenesis in mammals and other amniotes. As a step toward characterization of the evolutionary history of sexual development, we measured expression of FOXL2 and FGF9 across 3 developmental stages and 8 juvenile tissue types in male and female American alligators, Alligator mississippiensis. We report surprisingly high expression of FOXL2 before the stage of embryonic development when sex is determined in response to temperature, and sustained and variable expression of FGF9 in juvenile male, but not female tissue types. Novel characterization of gene expression in reptiles with temperature-dependent sex determination such as American alligators may inform the evolution of sex-determining and sex-differentiating gene networks, as they suggest alternative functions from which the genes may have been exapted. Future functional profiling of sex-differentiating genes should similarly follow other genes and other species to enable a broad comparison across sex-determining mechanisms. Copyright © 2013 S. Karger AG, Basel.

Boedeker N.C.,Smithsonians National Zoological Park | Guzzetta P.,Childrens National Medical Center | Rosenthal S.L.,Annapolis flyer cab | Padilla L.R.,Smithsonians National Zoological Park | And 2 more authors.
Comparative Medicine | Year: 2014

A 10-y-old ovariohysterectomized ring-tailed lemur (Lemur catta) was presented for exacerbation of respiratory signs. The lemur had a history of multiple examinations for various problems, including traumatic lacerations and recurrent perivulvar dermatitis. Examination revealed abnormal lung sounds and a femoral arteriovenous fistula with a palpable thrill and auscultable bruit in the right inguinal area. A diagnosis of congestive heart failure was made on the basis of exam findings, radiography, abdominal ultrasonography, and echocardiography. The lemur was maintained on furosemide until surgical ligation of the fistula was performed. Postoperative examination confirmed successful closure of the fistula and resolution of the signs of heart failure. Arteriovenous fistulas are abnormal connections between an artery and a vein that bypass the capillary bed. Large arteriovenous fistulas may result in decreased peripheral resistance and an increase in cardiac output with consequent cardiomegaly and high output heart failure. This lemur's high-flow arteriovenous fistula with secondary heart failure may have been iatrogenically induced during blood collection by prior femoral venipuncture. To our knowledge, this report is the first description of an arteriovenous fistula in a prosimian. Successful surgical correction of suspected iatrogenic femoral arteriovenous fistulas in a cynomolgus monkey (Macaca fascicularis) and a rhesus macaque (Macaca mulatta) have been reported previously. Arteriovenous fistula formation should be considered as a rare potential complication of venipuncture and as a treatable cause of congestive heart failure in lemurs.

Stanton L.A.,Manchester Metropolitan University | Sullivan M.S.,Manchester Metropolitan University | Fazio J.M.,Smithsonians National Zoological Park
Applied Animal Behaviour Science | Year: 2015

Standardized ethograms offer many practical benefits to behavioral researchers, and several examples exist today for various species and taxa. Despite historic evidence that suggests the family Felidae share similar behavioral repertoires, no standardized ethogram providing comprehensive behavioral definitions exists. In order to create a working ethogram for the Felidae, we conducted a thorough literature review of published articles and books containing behavioral definitions designed for felid species. A total of 95 documents qualified for inclusion, and each was evaluated to identify the terminology used in its behavioral definitions, along with any categorization implemented. The articles included the behaviors of 30 species and 40 subspecies of felids, with the most frequent single study species being the domestic cat (Felis catus), followed by several "big cats". The results were organized into the following mutually exclusive groups for comparison: domestic cat studies, big cat studies, and small cat studies excluding domestic cats (i.e. small exotic cats). Systematic review of definitions confirmed that researchers tend to define felid behavior in similar manners, although some divergence was found between the inclusion of behaviors in domestic and exotic (non-domestic) cat studies. Information from the literature review was used to create a standardized, universal ethogram for use in future felid behavioral studies. The final ethogram suggests the use of "base behaviors" which can be altered using pre-defined modifiers in order to accommodate the requirements of individual studies while retaining consistent terminology. Common behavioral categories are also defined, and suggestions of behaviors that qualify within each category are presented to further assist researchers when developing their study. The ethogram was designed to be user-friendly with clear definitions for each behavior, which should be coherent to a diverse range of observers. We anticipate that use of this ethogram will save researchers time and effort in creating behavioral definitions for their study, while also assisting in unifying felid behavioral research. © 2015.

Discover hidden collaborations