Body Condition Index Research Articles

Persistent organic pollutants in fat of three species of Pacific pelagic longline caught sea turtles: Accumulation in relation to ingested plastic marine debris

In addition to eating contaminated prey, sea turtles may be exposed to persistent organic pollutants (POPs) from ingesting plastic debris that has absorbed these chemicals. Given the limited knowledge about POPs in pelagic sea turtles and how plastic ingestion influences POP exposure, our objectives were to: 1) provide baseline contaminant levels of three species of pelagic Pacific sea turtles; and 2) assess trends of contaminant levels in relation to species, sex, length, body condition and capture location. In addition, we hypothesized that if ingesting plastic is a significant source of POP exposure, then the amount of ingested plastic may be correlated to POP concentrations accumulated in fat. To address our objectives we compared POP concentrations in fat samples to previously described amounts of ingested plastic from the same turtles. Fat samples from 25 Pacific pelagic sea turtles [2 loggerhead (Caretta caretta), 6 green (Chelonia mydas) and 17 olive ridley (Lepidochelys olivacea) turtles] were analyzed for 81 polychlorinated biphenyls (PCBs), 20 organochlorine pesticides, and 35 brominated flame-retardants. The olive ridley and loggerhead turtles had higher ΣDDTs (dichlorodiphenyltrichloroethane and metabolites) than ΣPCBs, at a ratio similar to biota measured in the South China Sea and southern California. Green turtles had a ratio close to 1:1. These pelagic turtles had lower POP levels than previously reported in nearshore turtles. POP concentrations were unrelated to the amounts of ingested plastic in olive ridleys, suggesting that their exposure to POPs is mainly through prey. In green turtles, concentrations of ΣPCBs were positively correlated with the number of plastic pieces ingested, but these findings were confounded by covariance with body condition index (BCI). Green turtles with a higher BCI had eaten more plastic and also had higher POPs. Taken together, our findings suggest that sea turtles accumulate most POPs through their prey rather than marine debris.

Trends in body condition of smallmouth bass and northern pike (1982–2013) following multiple ecological perturbations in the St. Lawrence River

Body condition indices can be used to investigate fish response to biological or environmental change. We used quantile regression to analyze a 32-year weight–length data set (1982–2013) for smallmouth bass (Micropterus dolomieu) and northern pike (Esox lucius) from the St. Lawrence River to examine changes in condition (weight-at-length) during three ecologically distinct time periods. Condition of both species varied among time periods, with smallmouth bass experiencing greater proportional changes than northern pike. Smallmouth bass weight-at-length was greatest during 2005–2013 and lowest during 1982–1992. Northern pike weight-at-length was greatest during 2005–2013 for quantiles ≥0.5, similar between the 1982–1992 and 2005–2013 time periods for lower quantiles, and lowest during 1993–2004. The most likely weight–length model for smallmouth bass included terms for length, presence of round goby (Neogobius melanostomus), presence of dreissenid mussels, and an interaction between length and dreissenid mussels (wi = 0.93). The most likely model for northern pike included terms for length, presence of round goby, presence of dreissenid mussels, water temperature, conspecific abundance, and sex (wi = 0.56). Invasive species and environmental change related to invasive species have altered the condition of smallmouth bass and northern pike in the St. Lawrence River.

067 Evaluation of body condition index in comparison with body condition score in horses and ponies

067 Evaluation of body condition index in comparison with body condition score in horses and ponies

A validation of 11 body-condition indices in a giant snake species that exhibits positive allometry.

Body condition is a gauge of the energy stores of an animal, and though it has important implications for fitness, survival, competition, and disease, it is difficult to measure directly. Instead, body condition is frequently estimated as a body condition index (BCI) using length and mass measurements. A desirable BCI should accurately reflect true body condition and be unbiased with respect to size (i.e., mean BCI estimates should not change across different length or mass ranges), and choosing the most-appropriate BCI is not straightforward. We evaluated 11 different BCIs in 248 Burmese pythons (Python bivittatus), organisms that, like other snakes, exhibit simple body plans well characterized by length and mass. We found that the length-mass relationship in Burmese pythons is positively allometric, where mass increases rapidly with respect to length, and this allowed us to explore the effects of allometry on BCI verification. We employed three alternative measures of ‘true’ body condition: percent fat, scaled fat, and residual fat. The latter two measures mostly accommodated allometry in true body condition, but percent fat did not. Our inferences of the best-performing BCIs depended heavily on our measure of true body condition, with most BCIs falling into one of two groups. The first group contained most BCIs based on ratios, and these were associated with percent fat and body length (i.e., were biased). The second group contained the scaled mass index and most of the BCIs based on linear regressions, and these were associated with both scaled and residual fat but not body length (i.e., were unbiased). Our results show that potential differences in measures of true body condition should be explored in BCI verification studies, particularly in organisms undergoing allometric growth. Furthermore, the caveats of each BCI and similarities to other BCIs are important to consider when determining which BCI is appropriate for any particular taxon.

Relationships between POPs, biometrics and circulating steroids in male polar bears (Ursus maritimus) from Svalbard

The aim of this study was to determine the effects of persistent organic pollutants (POPs) and biometric variables on circulating levels of steroid hormones (androgens, estrogens and progestagens) in male polar bears (Ursus maritimus) from Svalbard, Norway (n = 23). Levels of pregnenolone (PRE), progesterone (PRO), androstenedione (AN), dehydroepiandrosterone (DHEA), testosterone (TS), dihydrotestosterone (DHT), estrone (E1), 17α-estradiol (αE2) and 17β-estradiol (βE2) were quantified in polar bear serum by gas chromatography tandem mass spectrometry (GC-MS/MS), while POPs were measured in plasma. Subsequently, associations between hormone concentrations (9 steroids), POPs (21 polychlorinated biphenyls (PCBs), 8 OH-PCBs, 8 organochlorine pesticides (OCPs) and OCP metabolites, and 2 polybrominated diphenyl ethers (PBDEs)) and biological variables (age, head length, body mass, girth, body condition index), capture date, location (latitude and longitude), lipid content and cholesterol levels were examined using principal component analysis (PCA) and orthogonal projections to latent structures (OPLS) modelling. Average concentrations of androgens, estrogens and progestagens were in the range of 0.57–83.7 (0.57–12.4 for subadults, 1.02–83.7 for adults), 0.09–2.69 and 0.57–2.44 nmol/L, respectively. The steroid profiles suggest that sex steroids were mainly synthesized through the Δ-4 pathway in male polar bears. The ratio between androgens and estrogens significantly depended on sexual maturity with androgen/estrogen ratios being approximately 60 times higher in adult males than in subadult males. PCA plots and OPLS models indicated that TS was positively related to biometrics, such as body condition index in male polar bears. A negative relationship was also observed between POPs and DHT. Consequently, POPs and body condition may potentially affect the endocrinological function of steroids, including development of reproductive tissues and sex organs and the general condition of male polar bears.

Ecology, health and genetic characterization of the southernmost green turtle (Chelonia mydas) aggregation in the Eastern Pacific: implications for local conservation strategies

Bahia Salado, located in northern Chile (27°41’S, 70°59’W), is the southernmost foraging ground for the endangered green turtle (Chelonia mydas) in the Eastern Pacific Ocean (EPO). To date, almost no information exists on its current status, nor on its connectivity with nesting rookeries in the EPO. This study aims to inform on the genetic characterization, health and ecology of Bahia Salado’s green turtle aggregation in order to provide baseline information for local conservation strategies. We describe population structure and residency times using mark-recapture method. We also examine health parameters (body condition index, blood profile and blood copper-Cu and lead-Pb concentrations) and regional connectivity through genetic analyses. Our results indicate that this aggregation is composed exclusively of juveniles, with residency times varying between five to sixteen months. Turtles exhibited a very good body condition; however they showed the highest blood concentrations of Cu and Pb described for C. mydas and for almost all sea turtle species. Some biochemistry parameters (albumin, calcium, phosphorus, AST, triglycerides and creatinine) are also the highest ever reported for this species in the region. Analysis of the 770 bp (base pairs) control region of the mitochondrial DNA revealed four haplotypes, suggesting a strong genetic connectivity to the Galapagos rookery. Our study indicates that Bahia Salado’s aggregation represents a developmental foraging ground, where juvenile green turtles thrive. Although Bahia Salado’s ecosystem seems to be a very suitable habitat for the species, the high levels of Cu and Pb, together with elevated AST, demand further research on the negative impacts of heavy metals on this aggregation. Our results highlight the importance to protect this bay from anthropological activities, evaluate pollution sources and other local threats to this particular coastal ecosystem. We recommend year-round monitoring of the green turtle aggregation and other components of this ecosystem, incorporating participation of local seaweed collectors and the fishing community.

Potential effects of brevetoxins and toxic elements on various health variables in Kemp's ridley (Lepidochelys kempii) and green (Chelonia mydas) sea turtles after a red tide bloom event

Natural biotoxins and anthropogenic toxicants pose a significant risk to sea turtle health. Documented effects of contaminants include potential disease progression and adverse impacts on development, immune function, and survival in these imperiled species. The shallow seagrass habitats of Florida's northwest coast (Big Bend) serve as an important developmental habitat for Kemp's ridley (Lepidochelys kempii) and green (Chelonia mydas) sea turtles; however, few studies have been conducted in this area. Our objectives were (1) to evaluate plasma analytes (mass, minimum straight carapace length, body condition index [BCI], fibropapilloma tumor score, lysozyme, superoxide dismutase, reactive oxygen/nitrogen species, plasma protein electrophoresis, cholesterol, and total solids) in Kemp's ridleys and green turtles and their correlation to brevetoxins that were released from a red tide bloom event from July–October 2014 in the Gulf of Mexico near Florida's Big Bend, and (2) to analyze red blood cells in Kemp's ridleys and green turtles for toxic elements (arsenic, cadmium, lead, mercury, selenium, thallium) with correlation to the measured plasma analytes. Positive correlations were observed between brevetoxins and α2-globulins in Kemp's ridleys and α2- and γ-globulins in green turtles, indicating potential immunostimulation. Arsenic, cadmium, and lead positively correlated with superoxide dismutase in Kemp's ridleys, suggesting oxidative stress. Lead and mercury in green turtles negatively correlated with BCI, while mercury positively correlated with total tumor score of green turtles afflicted with fibropapillomatosis, suggesting a possible association with mercury and increased tumor growth. The total tumor score of green turtles positively correlated with total protein, total globulins, α2-globulins, and γ-globulins, further suggesting inflammation and immunomodulation as a result of fibropapillomatosis. Lastly, brevetoxin concentrations were positively related to tumor score, indicating potential tumor promotion by brevetoxin. These results signify that brevetoxins and toxic elements elicit various negative effects on sea turtle health, including immune function, oxidative stress, and possibly disease progression.

Life-history dependent relationships between plasma alkaline phosphatase activity and body condition in male Eurasian Tree Sparrows

BackgroundIn temperate-breeding birds, individuals must adjust their physiological states from one life-history stage to another in response to changing conditions to maximize ecological fitness. Previous evidences have shown that body mass, size-corrected mass (SCM), and hematocrit (Hct) could be used as estimates of the energetic state of individuals to illustrate life-history trade-offs and individual quality in field physiology. Plasma alkaline phosphatase (ALP) plays critical roles in regulating the metabolism of energy but very limited information is known on its link with body mass or Hct.MethodsWe determined the changes of plasma ALP levels in both early breeding and wintering stages of male Eurasian Tree Sparrows (Passer montanus), and examined the relationships between ALP and body mass, SCM, and Hct of the birds.ResultsOur study showed that (1) in male Eurasian Tree Sparrows, body mass did not vary with life-history stage but plasma ALP activity significantly increased in the wintering stage compared to the breeding stage; (2) ALP activity was not correlated with individual body mass but was positively correlated with individual SCM and Hct. Such positive correlations, however, only occurred in the wintering but not in the breeding stages.ConclusionsOur results suggest that plasma ALP activities in free-living birds can be used as one of the indicators of body condition or nutritional status for analyzing individual variation in the wintering but not in the breeding stages. The life-history dependent relationships between plasma ALP activity and body condition may contribute to our better understanding of the trade-off between individual survival and reproduction in free-living animals.

Behavioral, physiological and morphological correlates of parasite intensity in the wild Cururu toad (Rhinella icterica).

Large numbers of parasites are found in various organs of anuran amphibians, with parasite intensities thought to modulate the host's Darwinian fitness traits. Interaction between the anuran hosts and their multiple parasites should modulate the host's phenotypic characteristic, such as those associated with high energetic demand (such as calling effort and locomotor performance), energy balance (standard metabolic rate), and morphological plasticity (as indicated by organ masses). The present study investigated the impact of parasite intensities on the behavioral, physiological, and morphological traits of wild adult male Rhinella icterica (Anura: Bufonidae). We tested as to whether individuals with higher parasite intensities would present: 1) lower vocal calling effort in the field, as well as poorer locomotor performance and body-condition index; and 2) higher standard metabolic rates and internal organ masses. Measurements included: calling effort in the field; standard metabolic rate; locomotor performance; parasite intensity; internal organ masses (heart, liver, kidneys, intestines, stomach, lungs, hind limb muscle, and spleen); and the body-condition index. Results showed a negative association of parasite intensities with locomotor performance, and standard metabolic rate of R. icterica. A positive association between parasite intensities and relative organ masses (heart, intestines and kidneys) was also evident. Toads with higher pulmonary and intestinal parasites intensities also showed higher total parasite intensities.

Influence of the Herbicide Facet® on Corticosterone Levels, Plasma Metabolites, and Antioxidant System in the Liver and Muscle of American Bullfrog Tadpoles

This study sought to analyze the effects of the herbicide quinclorac on body condition indices; plasma levels of corticosterone, glucose, and uric acid; activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST); and levels of lipid peroxidation (LPO) in the liver and caudal muscle of American bullfrog (Rana catesbeiana) tadpoles. After a 7-day acclimation period, animals were exposed to four concentrations (0.05, 0.1, 0.2, and 0.4 μg/L) of herbicide for a further 7 days. Then, blood samples were obtained, animals were euthanized, and the liver and caudal muscle resected. Levels of corticosterone and uric acid were reduced in tadpoles exposed to the highest concentration of herbicide, and this reduction was preceded by an increase in glucose levels. In the liver tissue, LPO was increased after exposure to 0.1 μg/L quinclorac, followed by a return to baseline values in the remaining concentrations; this response was accompanied by an increase in SOD and GST and reduction of tissue protein levels. At the highest concentration, a reduction in activity of all enzymes was observed, with protein returning to control-like levels. In muscle, SOD and GST levels declined with exposures up to 0.1 g/L and 0.4 μg/L, respectively, whereas LPO decreased in animals exposed to 0.1 μg/L. These results suggest participation of nonenzymatic antioxidant defenses, as demonstrated by the reduction in uric acid levels. Exposure to the range of quinclorac concentrations used in this study slowed body mass and length gain, reduced corticosterone levels, and modulated antioxidant defenses.

Demographic and temporal variations in immunity and condition of polar bears (Ursus maritimus) from the southern Beaufort Sea.

Assessing the health and condition of animals in their natural environment can be problematic. Many physiological metrics, including immunity, are highly influenced by specific context and recent events to which researchers may be unaware. Thus, using a multifaceted physiological approach and a context-specific analysis encompassing multiple time scales can be highly informative. Ecoimmunological tools in particular can provide important indications to the health of animals in the wild. We collected blood and hair samples from free-ranging polar bears (Ursus maritimus) in the southern Beaufort Sea and examined the influence of sex, age, and reproductive status on metrics of immunity, stress, and body condition during 2013-2015. We examined metrics of innate immunity (bactericidal ability and lysis) and stress (hair cortisol, reactive oxygen species, and oxidative barrier), in relation to indices of body condition considered to be short term (urea to creatinine ratio; UC ratio) and long term (storage energy and body mass index). We found the factors of sex, age, and reproductive status of the bear were critical for interpreting different physiological metrics. Additionally, the metrics of body condition were important predictors for stress indicators. Finally, many of these metrics differed between years, illustrating the need to examine populations on a longer time scale. Taken together, this study demonstrates the complex relationship between multiple facets of physiology and how interpretation requires us to examine individuals within a specific context.

Bill colour pattern in Bewick’s swan: information on sex and body size displayed on face?

Ornamental traits in birds (plumage/bare part colours) have been shown to provide information on diverse aspects of individual quality and behaviour. In bird species with achromatic plumages (uniformly white, grey or black), signals encoded in bare parts are the major mode of visual communication. In this study we analysed the influence of sex, age, body condition and selected biometric traits on the bill colour pattern in Bewick’s swans Cygnus columbianus bewickii. The results indicate that sex and body size (weight and tarsus length) are associated with the bill colour pattern in Bewick’s swans. Individuals with a larger black area on the bill were heavier and had a longer tarsus. Moreover, females had more black on their bills than males did. Age, head length and body condition index were not significantly related to bill colour pattern. The present work indicates that Bewick’s swans may display information on their sex and size by means of their bill colour pattern. These findings also suggest the possibility that swans can remotely quantify one another’s traits from the appearance of their bill colouration. Proper assessment of an opponent or of mate quality during face-to-face signalling may help birds to avoid unnecessary interaction or to maintain bonds between mates and family groups.

Life-history dependent relationships between body condition and immunity, between immunity indices in male Eurasian tree sparrows

In free-living animals, recent evidence indicates that innate, and acquired, immunity varies with annual variation in the demand for, and availability of, food resources. However, little is known about how animals adjust the relationships between immunity and body condition, and between innate and acquired immunity to optimize survival over winter and reproductive success during the breeding stage. Here, we measured indices of body condition (size-corrected mass [SCM], and hematocrit [Hct]), constitutive innate immunity (plasma total complement hemolysis activity [CH50]) and acquired immunity (plasma immunoglobulin A [IgA]), plus heterophil/lymphocyte (H/L) ratios, in male Eurasian tree sparrows (Passer montanus) during the wintering and the breeding stages. We found that birds during the wintering stage had higher IgA levels than those from the breeding stage. Two indices of body condition were both negatively correlated with plasma CH50 activities, and positively with IgA levels in wintering birds, but this was not the case in the breeding birds. However, there was no correlation between CH50 activities and IgA levels in both stages. These results suggest that the relationships between body condition and immunity can vary across life-history stage, and there are no correlations between innate and acquired immunity independent of life-history stage, in male Eurasian tree sparrows. Therefore, body condition indices predict immunological state, especially during the non-breeding stage, which can be useful indicators of individual immunocompetences for understanding the variations in innate and acquired immunity in free-living animals.

Influence of body weight and body conformation on the pressure-volume curve during capnoperitoneum in dogs.

OBJECTIVE To evaluate the pressure-volume relationship during capnoperitoneum in dogs and effects of body weight and body conformation. ANIMALS 86 dogs scheduled for routine laparoscopy. PROCEDURES Dogs were allocated into 3 groups on the basis of body weight. Body measurements, body condition score, and body conformation indices were calculated. Carbon dioxide was insufflated into the abdomen with a syringe, and pressure was measured at the laparoscopic cannula. Volume and pressure data were processed, and the yield point, defined by use of a cutoff volume (COV) and cutoff pressure (COP), was calculated. RESULTS 20 dogs were excluded because of recording errors, air leakage attributable to surgical flaws, or trocar defects. For the remaining 66 dogs, the pressure-volume curve was linear-like until the yield point was reached, and then it became visibly exponential. Mean ± SD COP was 5.99 ± 0.805 mm Hg. No correlation was detected between yield point, body variables, or body weight. Mean COV was 1,196.2 ± 697.9 mL (65.15 ± 20.83 mL of CO2/kg), and COV was correlated significantly with body weight and one of the body condition indices but not with other variables. CONCLUSION AND CLINICAL RELEVANCE In this study, there was a similar COP for all dogs of all sizes. In addition, results suggested that increasing the abdominal pressure after the yield point was reached did not contribute to a substantial increase in working space in the abdomen. No correlation was found between yield point, body variables, and body weight.

Anisakis pegreffii (Nematoda: Anisakidae) in European anchovy Engraulis encrasicolus from the Mediterranean Sea: Fishing ground as a predictor of parasite distribution

European anchovy Engraulis encrasicolus represents one of the principal target species for commercial fishing in Europe. This fish is mostly consumed in different raw dish preparations, which represents a major risk for the fish-borne zoonosis anisakiasis. The present study provides a detailed epidemiological report on ascaridoid larvae in E. encrasicolus from several fishing areas in the Mediterranean basin. Between June 2013 and June 2016, a total of 4152 specimens of E. encrasicolus were obtained from 13 sampling areas. Parasitological analysis was carried out using the UV-press detection method. Anisakis larvae (N=547), identified by diagnostic allozymes and analyses of partial sequences of the EF1 α-1 region of nDNA and mtDNA cox2 gene, corresponded to Anisakis pegreffii. Additionally, sequence analyses of the ITS region of rDNA revealed the presence of Hysterothylacium aduncum larvae.The levels of infection with A. pegreffii significantly varied between the selected fishing areas. Fish from the Central and South Adriatic Sea showed the highest levels of infection. In contrast, anchovies from Southern Sicily, Ionian and Alboran Seas, were uninfected. A great majority of A. pegreffii larvae (95.8%) were located in the body cavity, whereas only a small percentage of them (4.2%) were detected in the flesh of the fish. A significant positive correlation between fish length and abundance of A. pegreffii was observed. The fish body condition index and infection levels observed in different sampling areas did not correlate significantly. The infection levels by H. aduncum also showed a significantly uneven distribution between different fishing areas of the Mediterranean Sea, and no larval specimens of H. aduncum were detected in examined fish flesh. This study is the first Mediterranean-wide epidemiological assessment of infection in the viscera and flesh of E. encrasicolus by A. pegreffii, an important causative agent of human anisakiasis.

Geometry Morphometry and Health Status of Hawksbill Turtle (Eretmochelys imbricata Linnaeus, 1766) in Maratua Island, East Kalimantan-Indonesia

<p class="Els-Abstract-text">Research on hawksbill turtles in the Maratua Island is still very few. Meanwhile, population of hawksbills was believed to decline due to human exploitation. The aim of this research was to study the morphology of hawksbill through geometric morphometric approach and health status which includes the existence of epibionts, mechanical damages and Body Condition Index. The survey was conducted from 5 to 18 September 2014. The method used was the hand˗catching by snorkeling and diving for catching turtles, morphometric measurements and documentation of the turtle body parts using the camera. Morphological aspects were analyzed with linear regression and geometry approach with Microsoft Excel and ImageJ software. Health status was analyzed with observation of epibionts and mechanical damages through photos and calculation of Body Condition Index. There were 11 turtles that have been caught. The results indicated the growth of straight carapace length notch to tip affect the growth of the other body parts of hawksbill turtle and based approach to geometry, shape growth of hawksbill turtles that are found in Maratua not changed but only have added size. Based on the health status through observation epibionts, mechanical damages and analysis of Body Condition Index, hawksbill in Maratua still relatively healthy compared with studies elsewhere.</p><div><p class="Els-keywords"><em> </em></p><p class="Els-keywords"><strong>Keywords:</strong> <em>Eretmochelys imbricata</em> (Linnaeus, 1766); geometry; Maratua; morphometry</p></div>

Effects of the herbicide triclopyr on metamorphic northern red-legged frogs.

Aquatic herbicides are used to manage invasive emergent plants in and around wetlands. Metamorphic frogs that emerge during the aquatic weed management season may be at risk of herbicide exposure. Metamorphic northern red-legged frogs (Rana aurora) were exposed to a triclopyr tank mix labeled for control of broadleaf emergent aquatic weeds such as invasive purple loosestrife (Lythrum salicaria). The tank mix consisted of Renovate® 3 (triclopyr triethylamine salt 44.4%), the modified vegetable oil surfactant Competitor®, and the marker dye Hi-Light® . Metamorphs were exposed to the tank mix and a clean-water control for 96 h, and then reared in clean water for 60 d. Exposure to the tank mix resulted in no treatment-related mortalities, no effects on behavior immediately post exposure, and no effects on body or liver condition indices. Exposure to the tank mix resulted in lethargy during exposure and a 1-d delay in completion of metamorphosis. Deformities present in the rearing population confounded results for some endpoints. Observed effects were minimal, especially compared with the potential for ecological impacts from unmanaged invasive plants. Environ Toxicol Chem 2017;36:2316-2326. © 2017 SETAC.

Short-term overfeeding of zebrafish with normal or high-fat diet as a model for the development of metabolically healthy versus unhealthy obesity

BackgroundObese individuals differ in their risk of developing metabolic and cardiovascular complications depending on fat distribution (subcutaneous versus visceral) and adipose tissue (AT) phenotype (hyperplasic versus hypertrophic). However, the exact mechanisms which determine whether an obese individual is metabolically healthy or unhealthy are not clear, and analyses of the underlying pathomechanisms are limited by the lack of suitable in vivo models in which metabolically healthy versus metabolically unhealthy AT accumulation can be specifically induced. In the current study, we aimed to establish a protocol for the use of zebrafish as a model for obesity-related metabolically healthy versus metabolically unhealthy AT accumulation.MethodsWe overfed adult male zebrafish of the AB strain with normal fat diet (NFD) or high fat diet (HFD) for 8 weeks and compared parameters related to obesity, i.e. body weight, body mass index, condition index and body fat percentage, to control zebrafish fed under physiological conditions. In addition, we investigated the presence of early obesity-related metabolic alterations by quantifying blood glucose levels, plasma triglyceride and cholesterol levels, and by assessing ectopic lipid accumulation in the liver of zebrafish. Finally, we determined gene expression levels of marker genes related to lipid metabolism, inflammation and fibrosis in visceral AT and liver.ResultsWe show that 8-weeks overfeeding with either NFD or HFD leads to a significant increase in body weight and AT mass compared to controls. In contrast to NFD-overfed zebrafish, HFD-overfed zebrafish additionally present metabolic alterations, e.g. hyperglycemia and ectopic lipid accumulation in the liver, and a metabolically unhealthy AT phenotype with adipocyte hypertrophy especially in the visceral AT depot, which is accompanied by changes in the expression of marker genes for lipid metabolism, inflammation and fibrosis.ConclusionsIn summary, we have established a method for the specific induction of metabolically distinct obesity phenotypes in zebrafish. Our results indicate that zebrafish represents an attractive model to study regulatory mechanisms involved in the determination of AT phenotype during development of metabolically healthy versus metabolically unhealthy obesity.

Spatio-temporal variation in the body condition of female pied flycatcher (Ficedula hypoleuca) in a polluted environment

Food-chain changes in urban and industrial sites may limit breeding-time resources (e.g. food availability) for small insectivorous passerines. We used a long-term data set of pied flycatchers (Ficedula hypoleuca), collected from one of the most polluted sites in Finland during the past 23 years to study the effects of metal pollution on body condition of breeding females. Our results show that body mass started to decline already some days before hatching, indicating a preparation of females to forthcoming chick feeding period. We did not find long-term temporal trends in female body condition index (BCI) in spite of considerably reduced metal emissions during the study period. However, females had higher BCI in polluted than in unpolluted areas during the incubation period. For both incubation and nestling periods the body condition was lower for later breeders, though the condition index decreased slightly faster in relation to hatching date in polluted areas, which may be due to more drastic decrease in nutrition rich food abundance. Temperature and clutch size were positively associated with BCI during the incubation period, but not in the nestling period. Overall, our data suggest that environmental pollution modifies important life-history traits, potentially via indirect effects of higher environmental variability and changed phenology in polluted environment.

Light pollution and seabird fledglings: Targeting efforts in rescue programs

ABSTRACTOne of the most critical phases in the life of petrels (Procellariiformes) is at fledging when young birds pass from parental dependence on land to an independent life at sea. To mitigate mortality at this time, rescue programs are implemented near breeding sites around the world, especially for birds grounded by artificial lights. We evaluated the plumage and body condition of short‐tailed shearwater (Ardenna tenuirostris) fledglings captured at colonies just before departure in comparison to fledglings washed up on beaches and to fledglings attracted by artificial light along roads. We measured abundance of down, body mass, and body condition index as the standardized residuals of a regression of body mass on size, and employed linear models to test differences on body mass and body condition between locations. Beach‐washed birds were underweight and in poor condition, suggesting their future survival probabilities at sea were low. Birds rescued on roads as a consequence of light attraction had lower body weights and condition indices than fledglings captured at the colony. However, more than 50% of light‐attracted birds had attained similar weights to those of adults, suggesting they have higher probabilities of survival than beach‐washed birds. Water‐logged birds being washed onto beaches is a natural process, but birds grounded by lighting along roads is an increasing anthropogenic threat that requires management. Thus, management and conservation efforts should be directed to protect birds in the colonies and reduce light‐induced mortality, ideally through the strategic reduction of light sources and lateral light spillage. When resources for conservation are limited, rescue programs should focus on rescuing birds from roads rather than beach‐washed birds, which have a lower probability of survival. © 2017 The Wildlife Society.