RESUMO
In contrast to mammals, the blood from other vertebrates such as fish contains nucleated red cells. Using a fathead minnow ( Pimephales promelas) oligonucleotide microarray, we compared altered transcripts in the liver and whole blood after exposure to environmentally relevant concentrations of perfluorooctanesulfonic acid (PFOS) and a mixture of seven types of perfluoro alkyl substances (PFAS), including perfluorooctanoic acid (PFOA). We used quantitative polymerase chain reactions and cell-based assays to confirm the main effects and found that blood responded with a greater number of altered genes than the liver. The exposure to PFAS altered similar genes with central roles in a cellular pathway in both tissues, including estrogen receptor α and peroxisome proliferator activator ß and γ, indicating that the genes previously associated with PFAS exposure are differentially expressed in blood and liver. The altered transcripts are involved with cholesterol metabolism and mitochondrial function. Our data confirmed that PFAS are weak xenoestrogens and exert effects on DNA integrity. Gene expression profiling from blood samples not related with the immune system, including very-low-density lipoprotein, vitellogenin, estrogen receptor, and thyroid hormone receptor, demonstrated that blood is a useful tissue for assessing endocrine disruption in non-mammalian vertebrates. We conclude that the use of blood for non-lethal sampling in genomics studies is informative and particularly useful for assessing the effects of pollution in endangered species. Further, using blood will reduce animal use and widen the experimental design options for studying the effects of contaminant exposure on wildlife.
Assuntos
Cyprinidae , Transcriptoma , Animais , Análise de Sequência com Séries de Oligonucleotídeos , Receptores de Estrogênio , VitelogeninasRESUMO
The effects of temperature on the growth of Caiman latirostris were investigated in order to evaluate the efficiency of food conversion at 29 and 33°C. Sixty-eight captive raised animals, two months old, taken from four nests, were used. All groups were maintained up to 70 or 72 days in similar environmental treatments except for temperature. Animals maintained at 33°C reached greater body mass (BM) and total length (TL) than those maintained at 29°C. A more efficient nutritional conversion rate was found in animals kept at 33°C. The increase of temperature could improve the amount of energy extracted from food, producing a more efficient FCR.
El efecto de la temperatura sobre el crecimiento de Caiman latirostris fue estudiado a fin de evaluar la eficacia de la conversión alimenticia en cautiverio a 29 y 33°C. Fueron utilizados 68 animales cautivos de dos meses de edad, provenientes de cuatro nidadas. Todos los grupos fueron mantenidos hasta por 70 o 72 días en tratamientos ambientales similares, a excepción de la temperatura. Los animales mantenidos a 33°C alcanzaron mayor peso y longitud total que aquellos mantenidos a 29°C. Una tasa de conversión alimenticia más eficiente fue encontrada en los animales criados a 33°C. El aumento de la temperatura podría mejorar la cantidad de energía extraída del alimento, produciendo un FCR más eficiente.
Para avaliação de um método econômico na criação em cativeiro de Jacaré-de-Papo-Amarelo (Caiman latirostris) estudio-se o consumo de ração, a taxa de conversão e o efeito da temperatura de cria no crescimento da espécie. Para este estudo foram utilizados 68 jacarés de dois meses de idade, nascidos de quatro ninhos coletados na natureza e incubados artificialmente. Durante o experimento os animais foram mantidos a duas temperaturas: 29ºC e 33ºC até 70 ou 72 dias. Como esperado, os animais mantidos a 33ºC mostraram maior taxa de crecimento (comprimento total e peso), e maior consumo de ração que aqueles mantidos a 29ºC. A taxa de conversão de alimento também foi mais efetiva quando a temperatura de cria foi maior. Concluí-se que o aumento da temperatura poderia melhorar a quantidade de energia extraída da ração, produzindo uma taxa de conversão mais eficiente.