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Deep ocean foraging northern elephant seals (Mirounga angustirostris) consume fish and squid in remote depths of the North Pacific Ocean. Contaminants bioaccumulated from prey are subsequently transferred by adult females to pups during gestation and lactation, linking pups to mercury contamination in mesopelagic food webs (200-1000 m depths). Maternal transfer of mercury to developing seal pups was related to maternal mercury contamination and was strongly correlated with maternal foraging behavior (biotelemetry and isotopes). Mercury concentrations in lanugo (hair grown in utero) were among the highest observed worldwide for young pinnipeds (geometric mean 23.01 μg/g dw, range 8.03-63.09 μg/g dw; n = 373); thus, some pups may be at an elevated risk of sub-lethal adverse health effects. Fetal mercury exposure was affected by maternal foraging geographic location and depth; mercury concentrations were highest in pups of the deepest diving, pelagic females. Moreover, pup lanugo mercury concentrations were strongly repeatable among successive pups of individual females, demonstrating relative consistency in pup mercury exposure based on maternal foraging strategies. Northern elephant seals are biosentinels of a remote deep-sea ecosystem. Our results suggest that mercury within North Pacific mesopelagic food webs may also pose an elevated risk to other mesopelagic-foraging predators and their offspring.

Eggshell thickness can be an indicator of environmental pollution in wild birds and shell quality in wild and domestic birds, but it is difficult to measure calcite eggshell thickness due to the presence of the adherent outer eggshell membrane. Eggshells of 13 waterbird species were divided in half longitudinally and the outer membrane was removed from one of the halves. Subsequently, we measured eggshell thickness, both with and without the outer eggshell membrane, using a Hall-effect thickness gauge to the nearest 0.001 mm along the equator of each eggshell half. Outer eggshell membrane thicknesses ranged from 0.014 to 0.073 mm. Caspian Tern (Hydroprogne caspia) and California Gull (Larus californiens) had the thickest eggshell membranes (0.056 and 0.073 mm, respectively), and Green Heron (Butorides virescens) and Killdeer (Charadrius vociferus) had the thinnest membranes (0.014 and 0.022 mm, respectively). The eggshell membrane, as a percent of the total eggshell and membrane thickness, varied among the 13 species and ranged among species from 7.9% to 20.6%. The outer membrane comprised a greater percent of the total eggshell and membrane thickness for Black Skimmer (19.3%; Rynchops niger), California Gull (20.5%), and Forster's Tern (20.6%; Sterna forsteri) than for Green Heron (7.9%), Double-crested Cormorant (10.4%; Phalacrocorax auritus), and Western Grebe (10.6%; Aechmophorus occidentalis). Within species, the outer membrane thickness was not correlated with egg morphometries but, for a subset of species, there was some indication that the calcite eggshell thickness decreases with embryo development (age). We discuss several reasons for conducting future eggshell thickness measurements without removing the membrane. Received 27 February 2023. Accepted 31 December 2023. Key words: eggshell measurement, eggshell membrane, eggshell thickness, Hall-effect thickness gauge. El grosor de la cascara de huevo puede ser indicador de la contaminacion ambiental en aves silvestres y de calidad de la cascara tanto en aves silvestres como domesticas, pero es dificil medir el grosor de la calcita de la cascara de huevo por la presencia de la membrana externa adherente. Cascaras de huevos de 13 especies de aves acuaticas fueron divididas en mitades longitudinales y la membrana externa fue removida de una de las dos mitades. Luego medimos el grosor de las cascaras de huevo, tanto con como sin membrana externa, usando calibrador de grosor de efecto Hall con al 0.001 mm mas cercano, proximo al ecuador de cada mitad de la cascara de huevo. El grosor de la membrana externa vario entre 0.014 to 0.073 mm. El charran Hydroprogne caspia y la gaviota Larus californicus tuvieron las membranas mas gruesas (0.056 and 0.073 mm, respectivamente), mientras que la garcita verde (Butorides virescens) y el chorlo Charadrius vociferus tuvieron las membranas mas delgadas (0.014 y 0.022 mm, respectivamente). La membrana del cascaron como porcentaje de la suma del grosor del cascaron y de la membrana, vario entre las 13 especies de 7.9% a 20.6%. La membrana externa represento un mayor porcentaje del grosor total de cascara de huevo y membrana para rayador Rynchops niger (19.3%), la gaviota (20.5%) y el charran Sterna forsteri (0.6%) que para la garcita verde (7.9%), cormoran Phalacrocorax auritus (10.4%) y archichilique Aechmophorus occidentalis (10.6%). Dentro de las especies, el grosor de la membrana externa no estaba correlacionado con la morfometria del huevo pero, para un subconjunto de especies, hubo algunos indicios de que el grosor de la calcita de la cascara de huevo disminuyo con el desarrollo del embrion (edad). Discutimos varias razones para llevar a cabo mediciones futuras de grosor de cascara de huevo sin remover la membrana. Palabras clave: medida de cascara de huevo, membrana de cascara de huevo, grosor de cascara de huevo, calibrador de grosor de efecto Hall., Eggshell thickness is used as an indicator of environmental pollution in wild birds, eggshell quality in wild and domestic birds (e.g., Blus 2011, Maurer et al. 2012), and to investigate [...]

Background: This study examined reasons not to drink in young adults in relation to demographics, alcohol use patterns, timing (weekend vs. weekday), and typical drinking motives. Methods: Young adults who reported past 30‐day alcohol use and at least one nondrinking day (n = 614; mean age = 21.5 years ±0.53) completed a survey of alcohol‐related measures (e.g., typical drinking motives) and up to 14 daily surveys that included 12 reasons not to drink assessed on nondrinking days. Multilevel logistic regressions were estimated for each reason not to drink and related covariates. Results: The most common reasons not to drink on a given day were "wasn't interested in drinking" (83.4% of nondrinking days) and "didn't want to get drunk" (81.8% of nondrinking days), with over 96% of participants endorsing each of these at least once. On days (11.6%; by 29.5% of participants) when another drug was used instead of alcohol, 81.8% used cannabis. Sex, race/ethnicity, weekend (vs. weekday), and drinking motives were differentially linked to reasons not to drink. Reporting high‐intensity drinking (i.e., ≥10 drinking on a day) versus binge (5–9 drinks on a day) in the past 2 weeks was linked to "had a hangover recently" (odds ratio = 2.85) as a reason not to drink. Conclusions: Findings suggest that reasons not to drink reflect personal decisions and highlight ways to acknowledge situational barriers (e.g., saving money for food and essentials) that can be emphasized in brief interventions. Furthermore, reasons not to drink and alcohol motives may work in tandem within the motivational model to impact alcohol use behaviors. [ABSTRACT FROM AUTHOR]

Simple Summary: In our study, we looked into finding better ways to diagnose and predict acute kidney injury (AKI) in dogs. To do so, two substances were studied in dog urine, urinary clusterin (uClust) and cystatin B (uCysB), to see if they could be useful as markers for AKI. We compared samples from 18 dogs with different levels of AKI and 10 healthy dogs. Dogs with AKI initially had higher levels of uClust and uCysB than healthy dogs. Also, the level of uCysB was higher in dogs that did not survive. In conclusion, uClust and uCysB seem to be promising markers for diagnosing and predicting the outcome of AKI in dogs. Novel biomarkers are needed in diagnosing reliably acute kidney injury (AKI) in dogs and in predicting morbidity and mortality after AKI. Our hypothesis was that two novel tubular biomarkers, urinary clusterin (uClust) and cystatin B (uCysB), are elevated in dogs with AKI of different etiologies. In a prospective, longitudinal observational study, we collected serum and urine samples from 18 dogs with AKI of different severity and of various etiology and from 10 healthy control dogs. Urinary clusterin and uCysB were compared at inclusion between dogs with AKI and healthy controls and remeasured one and three months later. Dogs with AKI had higher initial levels of uClust (median 3593 ng/mL; interquartile range [IQR]; 1489–10,483) and uCysB (554 ng/mL; 29–821) compared to healthy dogs (70 ng/mL; 70–70 and 15 ng/mL; 15–15; p < 0.001, respectively). Initial uCysB were higher in dogs that died during the one-month follow-up period (n = 10) (731 ng/mL; 517–940), compared to survivors (n = 8) (25 ng/mL; 15–417 (p = 0.009). Based on these results, uClust and especially uCysB are promising biomarkers of AKI. Further, they might reflect the severity of tubular injury, which is known to be central to the pathology of AKI. [ABSTRACT FROM AUTHOR]

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Background: Low-pass whole-genome sequencing and imputation offer significant cost savings, enabling substantial increases in sample size and statistical power. This approach is particularly promising in livestock breeding, providing an affordable means of screening individuals for deleterious alleles or calculating genomic breeding values. Consequently, it may also be of value in companion animal genomics to support pedigree breeding. We sought to evaluate in dogs the impact of low coverage sequencing and reference-guided imputation on genotype concordance and association analyses. Results: DNA isolated from saliva of 30 Labrador retrievers was sequenced at low (0.9X and 3.8X) and high (43.5X) coverage, and down-sampled from 43.5X to 9.6X and 17.4X. Genotype imputation was performed using a diverse reference panel (1021 dogs), and two subsets of the former panel (256 dogs each) where one had an excess of Labrador retrievers relative to other breeds. We observed little difference in imputed genotype concordance between reference panels. Association analyses for a locus acting as a disease proxy were performed using single-marker (GEMMA) and haplotype-based (XP-EHH) tests. GEMMA results were highly correlated (r ≥ 0.97) between 43.5X and ≥ 3.8X depths of coverage, while for 0.9X the correlation was lower (r ≤ 0.8). XP-EHH results were less well correlated, with r ranging from 0.58 (0.9X) to 0.88 (17.4X). Across a random sample of 10,000 genomic regions averaging 17 kb in size, we observed a median of three haplotypes per dog across the sequencing depths, with 5% of the regions returning more than eight haplotypes. Inspection of one such region revealed genotype and phasing inconsistencies across sequencing depths. Conclusions: We demonstrate that saliva-derived canine DNA is suitable for whole-genome sequencing, highlighting the feasibility of client-based sampling. Low-pass sequencing and imputation require caution as incorrect allele assignments result when the subject possesses alleles that are absent in the reference panel. Larger panels have the capacity for greater allelic diversity, which should reduce the potential for imputation error. Although low-pass sequencing can accurately impute allele dosage, we highlight issues with phasing accuracy that impact haplotype-based analyses. Consequently, if accurately phased genotypes are required for analyses, we advocate sequencing at high depth (> 20X). [ABSTRACT FROM AUTHOR]