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1.
Zoo Biol ; 41(6): 560-575, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35137968

RESUMO

In this paper, we cover 4 years of live fish transports that ranged from 14 to 200 h (8 days), and bioloads from 3.8 to 76.9 kg/m3 . The key ingredients for success in all trips, where virtually no mortality occurred, was atributed to (1) pre-buffering the water with sodium bicarbonate and sodium carbonate at 50 g/m3 (each)-and/or ATM Alka-HaulTM at 25 g/m3 -and applying additional (partial or full) doses throughout each transport, whenever the tanks were accessible; (2) pre-quenching ammonia with ATM TriageTM at 32 g/m3 , and applying additional (partial or full) doses throughout each transport, whenever the tanks were accessible; (3) keeping the dissolved oxygen saturation rate above 100%, ideally above 150%; (4) Keeping temperature on the lower limit of each species' tolerance range; (5) Using foam fractionators to effectively eliminate organic matter from the water and (6) Using pure sine wave inverters, which allows for a steady supply of electrical current throughout the transport. The use of a 'preventive' versus 'corrective' pH buffering philosophy is also discussed.


Assuntos
Salmo salar , Animais , Água , Animais de Zoológico
2.
Animals (Basel) ; 14(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38540001

RESUMO

After hatching, sea turtles leave the nest and disperse into the ocean. Many years later, they return to their natal coastlines. The period between their leaving and their returning to natal areas, known as the "Lost Years", is poorly understood. Satellite tracking studies aimed at studying the "Lost Years" are challenging due to the small size and prolonged dispersal phases of young individuals. Here, we summarize preliminary findings about the performance of prototype microsatellite tags deployed over a three-year period on 160 neonate to small juvenile sea turtles from four species released in the North Atlantic Ocean. We provide an overview of results analyzing tag performance with metrics to investigate transmission characteristics and causes of tag failure. Our results reveal that, despite certain unfavorable transmission features, overall tag performance was satisfactory. However, most track durations were shorter than those observed on individuals of similar size in other studies and did not allow for detailed analyses of trajectories and turtle behavior. Our study further suggests that tracking durations are correlated with the targeted species, highlighting a lack of robustness against some neritic behaviors. Unprecedented diving data obtained for neonate sea turtles in this study suggest that the vertical behaviors of early juveniles are already too strenuous for these miniaturized tags. Our findings will help to inform the biologging research community, showcasing recent technological advances for the species and life stages within our study.

3.
Trends Ecol Evol ; 36(8): 691-699, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34016477

RESUMO

Elevated temperatures during development affect a wide range of traits in ectotherms. Less well understood is the impact of global warming on brain development, which has only rarely been studied experimentally. Here, we evaluate current progress in the field and search for common response patterns among ectotherm groups. Evidence suggests that temperature may have a positive effect on neuronal activity and growth in developing brains, but only up to a threshold, above which temperature is detrimental to neuron development. These responses appear to be taxon dependent but this assumption may be due to a paucity of data for some taxonomic groups. We provide a framework with which to advance this highly promising field in the future.


Assuntos
Encéfalo , Aquecimento Global , Mudança Climática , Temperatura
4.
Physiol Biochem Zool ; 94(5): 302-318, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34260339

RESUMO

AbstractThermal conditions during embryonic development affect offspring phenotype in ectotherms. Therefore, rising environmental temperatures can have important consequences for an individual's fitness. Nonetheless, females have some capacity to compensate for potential negative consequences that adverse developmental environments may have on their offspring. Recent studies show that oviparous reptiles exhibit behavioral plasticity in nest site selection, which can buffer their embryos against high incubation temperatures; however, much less is known about these responses in viviparous reptiles. We subjected pregnant viviparous skinks, Saiphos equalis, to current or projected midcentury (2050) temperatures to test (i) how elevated temperatures affect female thermoregulatory and foraging behavior; (ii) whether temperatures experienced by females during pregnancy negatively affect the morphology, performance, and behavior of hatchlings; and (iii) whether behavioral thermoregulation during pregnancy is costly to females. Females from the elevated temperature treatment compensated by going deeper belowground to seek cooler temperatures and eating less, and they consequently had a lower body mass relative to snout-to-vent length (condition estimator) compared with females from the current thermal treatment. The temperatures experienced by females in the elevated temperature treatment were high enough to affect foraging and locomotor performance but not the morphology and growth rate of hatchlings. By seeking cooler temperatures, mothers can mitigate some of the effects of high temperatures on their offspring (e.g., reduced body size and growth). However, this protective behavior of females may come at an energetic cost to them. This study adds to growing evidence of lizards' vulnerability to global warming, particularly during reproduction when females are already paying a substantial cost.


Assuntos
Lagartos , Condicionamento Físico Animal , Animais , Regulação da Temperatura Corporal , Feminino , Aquecimento Global , Humanos , Mães , Temperatura
5.
J Comp Physiol B ; 190(6): 795-809, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32951106

RESUMO

Early developmental environments influence life-history traits and survival of reptiles. In fact, rising global temperatures have already caused widespread extinctions among lizards. Viviparous species might be more susceptible to increasing temperatures because of their inability to meet their energetic demands following rapid environmental changes. Nevertheless, we do not yet fully understand how lizards with different reproductive modes can respond to climate change. We investigated the effect of both maternal thermal environment during pregnancy and incubation temperature on hatchling morphology and physiological performance of two populations of the lizard Saiphos equalis differing in their mode of reproduction, to test whether reproductive mode affects the ability to buffer against rising temperatures. Gravid females from both populations were subjected to current or projected end-of-century (future) thermal environments, to evaluate differences in the body size, growth rate, thermal preference, and locomotor performance of their offspring. Our results show that independently of the mode of reproduction, high temperatures accelerated gestation periods. Thermal environments did not affect hatchling thermal preference, but viviparous hatchlings consistently preferred lower temperatures. Unlike viviparous lizards, oviparous hatchlings incubated under future temperatures were smaller and had a lower growth rate compared to current-incubated hatchlings. Finally, thermal environments did not affect hatchling endurance and speed when controlling for body size. Our results show that global warming is likely to have a negative impact on S. equalis, but suggest that some of its effects may be ameliorated by maternal responses during pregnancy, particularly in viviparous populations.


Assuntos
Lagartos/fisiologia , Temperatura , Animais , Tamanho Corporal , Meio Ambiente , Feminino , Lagartos/crescimento & desenvolvimento , Locomoção , Oviparidade , Reprodução , Viviparidade não Mamífera
6.
J Inflamm (Lond) ; 17(1): 35, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33292260

RESUMO

BACKGROUND: Obesity configures a pathophysiological profile that predisposes the development of metabolic and cardiovascular diseases, critically impacting public health. The chronic dysregulation of immuno-metabolic components triggered by pediatric obesity is a common but scarcely understood aspect of the disease. Peroxisome proliferator-activated receptors (PPARs) are a group of transcription factors essential for energy and immune homeostasis of different tissues. Besides, the glucagon-like peptide-1 receptor (GLP-1R) activation influences insulin secretion, but also regulates the cytokine profile possibly mediated through a PPAR isotype. However, the role of PPARs and GLP-1R in leukocytes from obese pediatric patients remains unclear. Therefore, we examined the expression of PPARs isotypes and GLP-1R in leukocytes, and its correlation with metabolic, hormonal, inflammatory, and anthropometric markers in an obese pediatric population. RESULTS: Obese children and adolescents presented a significant increase in anthropometric and body composition parameters, TG, VLDL, TG/HDL, android fat (%)/gynoid fat (%) (A/G%) index, and HOMA score when compared with the control group. Obese participants exhibited a pro-inflammatory profile with an augment of IL-8 (p = 0,0081), IL-6 (p = 0,0005), TNF-α (p = 0,0004), IFN-γ (p = 0,0110), MCP-1 (p = 0,0452), and adipsin (p = 0,0397), whereas displayed a reduction of adiponectin (p = 0,0452). The expression of PPARα and GLP-1R was lower in the leukocytes from obese participants than in lean subjects. Furthermore, PPARα correlates negatively with TNF-α (p = 0,0383), while GLP-1R did not show correlation with any inflammatory variable. However, both receptors correlate negatively with the abdominal skinfold. Although PPARß/δ expression was similar between groups, it was negatively associated with IL-8 levels (p = 0,0085). CONCLUSIONS: PPARα and PPARß/δ expression are negatively correlated with the proinflammatory markers TNF-α and IL-8, respectively, suggesting participation in the regulation of inflammation which was observed to be altered in pediatric obesity. Furthermore, PPARα and GLP-1R are downregulated in leukocytes from obese participants. The low expression of both receptors is correlated with an increase in abdominal skinfold, suggesting a role in fat distribution that could indirectly affect cytokine secretion from different immune and adipose cells, likely triggering an inflammatory profile as a consequence of obesity. Altogether, these findings may impact the understanding and implementation of PPARα or GLP-1R agonists in the clinic.

7.
Zootaxa ; 4648(3): zootaxa.4648.3.8, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31716940

RESUMO

The frogs of the genus Pristimantis are recognized for their characteristic reproductive mode and for their incredible diversity of species, becoming the genus with the highest number of species within tetrapod vertebrates. We describe here a new species of Pristimantis from the northwestern Andes of Colombia. The species was found between 2000-2500 m.a.s.l., mostly within moss hanging of tree branches in a tropical cloud forest. It can be easily distinguished from other Pristimantis species of the western Andes by the unique black and white patterning in the ventral surface and the flanks, the hourglass-shaped dorsal folds, and the prominent conical tubercles on eyelids, heels, and outer edge of tarsus. A phylogenetic analysis further supports its status of a lineage reciprocally monophyletic to P. satagius and separated by a genetic distance of 0.03; the latter species bear whitish rather than predominantly black ventral coloration. To the best of our knowledge, this species is only known from the 2,500 ha nature reserve Mesenia-Paramillo, despite other research on this area of the country. Therefore, the species is declared vulnerable while new evidence on its distribution range is accumulated.


Assuntos
Anuros , Florestas , Animais , Colômbia , Filogenia
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