19 research outputs found
Percent mortality and infection among embryo, hatchling, larval, and metamorphosis developmental stages for <i>Lithobates sylvaticus</i>, <i>L. pipiens</i>, <i>L. clamitans</i>, <i>Anaxyrus americanus</i>, <i>Pseudacris feriarum</i>, <i>Hyla chrysoscelis</i>, and <i>Scaphiopus holbrookii</i>.
<p>Similar shaded bars with unlike letters are different (<i>P</i><0.006) by logistic regression analysis; <i>n</i> = 20 per developmental stage for each species.</p
Quantity of egg masses and collection sites in Tennessee and Pennsylvania, USA.
<p>Quantity of egg masses and collection sites in Tennessee and Pennsylvania, USA.</p
Infection of individuals exposed to ranavirus directly or indirectly.
<p>Infection prevalence between individuals exposed to ranavirus inoculum (direct) or via shedding (indirect) by a paired host. Treatments were paired individuals (<i>n</i> = 20 per bar) of different ectothermic vertebrate classes (A = amphibian, R = reptile, F = fish); thus, A|F = amphibian paired with fish. Infection of indirectly exposed individuals is evidence of waterborne transmission by directly exposed individuals.</p
Maternal Health Status Correlates with Nest Success of Leatherback Sea Turtles (<em>Dermochelys coriacea</em>) from Florida
<div><p>Of the seven sea turtle species, the critically endangered leatherback sea turtle (<em>Dermochelys coriacea</em>) exhibits the lowest and most variable nest success (i.e., hatching success and emergence success) for reasons that remain largely unknown. In an attempt to identify or rule out causes of low reproductive success in this species, we established the largest sample size (n = 60–70 for most values) of baseline blood parameters (protein electrophoresis, hematology, plasma biochemistry) for this species to date. Hematologic, protein electrophoretic and biochemical values are important tools that can provide information regarding the physiological condition of an individual and population health as a whole. It has been proposed that the health of nesting individuals affects their reproductive output. In order to establish correlations with low reproductive success in leatherback sea turtles from Florida, we compared maternal health indices to hatching success and emergence success of their nests. As expected, hatching success (median = 57.4%) and emergence success (median = 49.1%) in Floridian leatherbacks were low during the study period (2007–2008 nesting seasons), a trend common in most nesting leatherback populations (average global hatching success = ∼50%). One protein electrophoretic value (gamma globulin protein) and one hematologic value (red blood cell count) significantly correlated with hatching success and emergence success. Several maternal biochemical parameters correlated with hatching success and/or emergence success including alkaline phosphatase activity, blood urea nitrogen, calcium, calcium∶phosphorus ratio, carbon dioxide, cholesterol, creatinine, and phosphorus. Our results suggest that in leatherbacks, physiological parameters correlate with hatching success and emergence success of their nests. We conclude that long-term and comparative studies are needed to determine if certain individuals produce nests with lower hatching success and emergence success than others, and if those individuals with evidence of chronic suboptimal health have lower reproductive success.</p> </div
Synopsis of hematologic values for leatherback sea turtles from the literature (Atlantic Ocean) and this study.
a<p>PCV = Packed cell volume, RBC = Red blood cells, WBC = White blood cells.</p>b<p>2007 season only.</p>c<p>Deem et al. (2006); nesting females.</p>d<p>Innis et al. (2010); combined data from directly captured and entangled male and female leatherbacks (not significantly different) from Georgia, USA and Massachusetts, USA.</p>e<p>Estimated from blood cell counts.</p>f<p>Significant difference between directly captured (D, n = 11) and entangled (E, n = 7) leatherbacks.</p>g<p>Significant difference between male and female leatherbacks.</p>h<p>Monocytes (%) = ±SD: Directly captured = 2±1 (n = 11), Entangled = 7±8 (n = 7), Male = 1±2 (n = 9), Female = 4±5 (n = 4); Range: Directly captured = 0–5, Entangled = 0–13, Male = 0–5, Female = 1–11.</p
Poor biosecurity could lead to disease outbreaks in animal populations
<div><p>Human-mediated disease outbreaks due to poor biosecurity practices when processing animals in wild populations have been suspected. We tested whether not changing nitrile gloves between processing wood frog (<i>Lithobates sylvaticus</i>) tadpoles and co-housing individuals increased pathogen transmission and subsequent diseased-induced mortality caused by the emerging pathogen, ranavirus. We found that not changing gloves between processing infected and uninfected tadpoles resulted in transmission of ranavirus and increased the risk of mortality of uninfected tadpoles by 30X. Co-housing tadpoles for only 15 minutes with 10% of individuals infected resulted in ranavirus transmission and 50% mortality of uninfected tadpoles. More extreme mortality was observed when the co-housing infection prevalence was >10%. Our results illustrate that human-induced disease outbreaks due to poor biosecurity practices are possible in wild animal populations.</p></div
The difference in the instantaneous rate of mortality (i.e., hazard ratio) for uninfected wood frog (<i>Lithobates sylvaticus</i>) tadpoles that were processed with and without changing gloves (yes vs. no) at two known ranavirus infection prevalence levels (10 vs. 40%).
<p>The difference in the instantaneous rate of mortality (i.e., hazard ratio) for uninfected wood frog (<i>Lithobates sylvaticus</i>) tadpoles that were processed with and without changing gloves (yes vs. no) at two known ranavirus infection prevalence levels (10 vs. 40%).</p
Synopsis of plasma biochemical data for leatherback sea turtles from this study (Florida).
a<p>ALT = Alanine aminotransferase, ALKP = Alkaline phosphatase, AST = Aspartate aminotransferase, BUN = Blood urea nitrogen, Ca∶P = Calcium∶phosphorus ratio, CK = Creatine kinase, LDH = Lactate dehydrogenase.</p>b<p>2008 season only.</p>c<p>2007 season only.</p
Poor biosecurity could lead to disease outbreaks in animal populations - Fig 1
<p>(A) Survival of uninfected wood frog (<i>Lithobates sylvaticus</i>) tadpoles that were processed with infected tadpoles at different levels of infection prevalence with and without changing gloves, (B) corresponding mortality and infection prevalence for 3 of 5 replicates in (A), (C) survival of uninfected wood frog tadpoles that were co-housed with infected tadpoles at different levels of infection prevalence and for different durations, (D) corresponding mortality and infection prevalence for 3 of 5 replicates in (C).</p
Least-squares linear regression results for health parameters and date of nesting encounter.
a<p>ALKP = Alkaline phosphatase, BUN = Blood urea nitrogen, CO<sub>2</sub> = Carbon dioxide, Corr = Correlation, PCV = Packed cell volume, RBC = Red blood cell, WBC = White blood cell.</p>b<p>Log transformed.</p>c<p>Rank regression.</p