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1.
Poult Sci ; 99(11): 5501-5508, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33142468

RESUMO

Providing green light during incubation has been shown to accelerate the embryo development and shorten the hatching time in broilers. Few studies have concentrated on the exact effects on layer breeders in the aspects of hatching and posthatch performance. In this study, 4 strains of layer breeder eggs, namely White Leghorn, Rhode Island Red, Columbia Rock, and Barred Rock were used to assess the effects of monochromatic green light during embryogenesis on hatching performance, chick quality, and pubertal growth. Each strain of 600 eggs was incubated under photoperiods of either 12 h of light and 12 h of darkness (12L:12D, light group) or 0 h of light and 24 h of darkness (0L:24D, dark group) for 18 D, with 2 replicates for each treatment. The results showed hatch time, time reaching 90% hatch, and average hatch time were significantly shorter among the 4 strains in the light group (P < 0.01). In addition, hatch window and peak hatching period were not extended by the green light stimulation (P > 0.05). There was no significant difference in hatchability of fertile eggs, chick weight/egg weight, or chick quality among the 4-strain eggs between the light group and dark group (P > 0.05). There was no difference (P > 0.05) in posthatch BW between different light treatments of the 3 strains (White Leghorn, Columbia Rock, and Barred Rock), whereas the BW of Rhode Island Red was higher in light group than that of the dark group at 8 to 12 wk of age (P < 0.05) and the difference disappeared from week 14. The results demonstrate that 12L:12D monochromatic green light stimulation during embryogenesis shortens the hatching time with no negative effects on hatching and posthatch performance. These effects were consistent among the 4 layer strains.


Assuntos
Galinhas , Desenvolvimento Embrionário , Crescimento , Luz , Animais , Desenvolvimento Embrionário/efeitos da radiação , Fertilidade , Crescimento/efeitos da radiação , Fotoperíodo , Especificidade da Espécie , Zigoto/crescimento & desenvolvimento , Zigoto/efeitos da radiação
2.
Poult Sci ; 99(11): 5517-5525, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33142470

RESUMO

Qualities of the light environment, such as the spectral composition of light, have been shown to impact growth and performance of broiler chickens. UVA light is visible to broiler chickens, whereas UVB wavelengths promote endogenous vitamin D synthesis, which could support their rapid development. The aim of the current study was to investigate the impacts of supplementary UVA and UVB wavelengths on performance indicators of broiler chickens. Day-old Ross 308 chicks (n = 638), reared to a target stocking density of 33 kg/m2, were randomly assigned to 1 of 3 lighting treatments: A) White light emitting diode (LED) and supplementary UVA LED lighting (18-h photoperiod); B) White LED with supplementary UVA and UVB fluorescent lighting providing 30 µW/cm2 UVB at bird level (lights on for 8 h of the total photoperiod to avoid overexposure of UVB); and C) White LED control group, representative of farm conditions (18-h photoperiod). Mortality was recorded, and broiler chickens were individually weighed at 8, 15, 22, 27, and 34 D of age. Generalized linear models and nonlinear mixed effects models (Gompertz curve) were fitted to determine the effects of UV wavelengths on broiler mortality and growth performance. UV did not impact breast or leg weight of broiler chickens but was associated with differences in mortality, growth, and end weight. Broiler chickens provided with UVA for the full 18-h photoperiod had slower initial growth than control broilers and a reduction in mortality. Results from male broilers reared with supplementary UVA + UVB for 8 h indicated they could reach finishing weights sooner than controls, which supports the potential for UVA + B to improve the growth performance of males. Results suggest that the provision of supplementary UVA + UVB wavelengths may improve the performance of male broiler chickens. The reduction in mortality in the UVA only treatment may warrant further investigation. The inclusion of UV wavelengths within poultry lighting regimes represents a promising area of further study.


Assuntos
Galinhas , Crescimento , Raios Ultravioleta , Animais , Peso Corporal/efeitos da radiação , Galinhas/crescimento & desenvolvimento , Crescimento/efeitos da radiação , Masculino , Fotoperíodo
3.
Toxicology ; 410: 142-151, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30321649

RESUMO

Exposure to environmental toxicants may affect reproduction and development of subsequent generations. This study was aimed at determining the male-mediated F1 effects induced following 8-weeks of subchronic exposure of F0 male mice to bisphenol A (BPA) alone and in a combination with X-rays irradiation (IR) started during their puberty. 4.5 weeks old F0 male mice were exposed to BPA dissolved in ethyl alcohol and diluted in drinking water at the following doses: 5 mg/kg bw, 10 mg/kg bw, 20 mg/kg bw or irradiated with X-rays (0.05 Gy) or exposed to a combination of low doses of both agents (0.05 Gy + 5 mg/kg bw BPA). Immediately after the end of the 8 weeks exposure F0 males were caged with two unexposed females each. Three quarters of the mated females from each group were sacrificed 1 day before expected parturition for examination of prenatal development of the offspring. The remainder of the females from each group were allowed to deliver and rear litters. Pups of exposed males were monitored for postnatal development for 8 weeks. At 8-9 weeks of age 6-8 males from each group of F1 generation were sacrificed to determine sperm count and quality. The current results, compared to the earlier results, showed that exposure of pubescent males to BPA alone or in combination with irradiation may be more damaging to their offspring than the exposure of adult males. The exposure of pubescent males to BPA alone and in combination with irradiation significantly increased the frequency of abnormal skeletons of surviving fetuses, increased the percent of mortality of pups in the F1 generation, reduced the sperm motility of F1 males and may induce obesity. Additionally, the combined BPA and irradiation exposure reduced the number of total and live implantations, whereas the exposure to BPA alone disturbed the male:female sex ratio. The above results may be caused by genetic or by epigenetic mechanisms. Limitation of use of products including BPA, especially by children and teenagers, is strongly recommended.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Fenóis/toxicidade , Reprodução/efeitos dos fármacos , Reprodução/efeitos da radiação , Raios X , Anormalidades Induzidas por Medicamentos/patologia , Anormalidades Induzidas por Radiação/patologia , Animais , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Desenvolvimento Fetal/efeitos da radiação , Crescimento/efeitos dos fármacos , Crescimento/efeitos da radiação , Masculino , Camundongos , Gravidez , Análise do Sêmen , Maturidade Sexual , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos da radiação , Testículo/efeitos dos fármacos , Testículo/patologia , Testículo/efeitos da radiação
4.
Int J Radiat Biol ; 91(3): 286-93, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25488006

RESUMO

PURPOSE: To examine the impact of electromagnetic radiation, produced by GSM (Global System for Mobile communications) mobile phones, Wi-Fi (Wireless-Fidelity) routers and wireless DECT (Digital Enhanced Cordless Telecommunications) phones, on the nematode Caenorhabditis elegans. MATERIALS AND METHODS: We exposed synchronized populations, of different developmental stages, to these wireless devices at E-field levels below ICNIRP's (International Commission on Non-Ionizing Radiation Protection) guidelines for various lengths of time. WT (wild-type) and aging- or stress-sensitive mutant worms were examined for changes in growth, fertility, lifespan, chemotaxis, short-term memory, increased ROS (Reactive Oxygen Species) production and apoptosis by using fluorescent marker genes or qRT-PCR (quantitative Reverse Transcription-Polymerase Chain Reaction). RESULTS: No statistically significant differences were found between the exposed and the sham/control animals in any of the experiments concerning lifespan, fertility, growth, memory, ROS, apoptosis or gene expression. CONCLUSIONS: The worm appears to be robust to this form of (pulsed) radiation, at least under the exposure conditions used.


Assuntos
Caenorhabditis elegans/efeitos da radiação , Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Animais , Animais Geneticamente Modificados , Apoptose/efeitos da radiação , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/fisiologia , Quimiotaxia/efeitos da radiação , Feminino , Fertilidade/efeitos da radiação , Expressão Gênica/efeitos da radiação , Genes de Helmintos/efeitos da radiação , Crescimento/efeitos da radiação , Longevidade/efeitos da radiação , Masculino , Memória de Curto Prazo/efeitos da radiação , Degeneração Neural/etiologia , Radiobiologia , Espécies Reativas de Oxigênio/metabolismo , Tecnologia sem Fio
5.
Theor Biol Med Model ; 11: 44, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-25312098

RESUMO

BACKGROUND: Children receiving Total Body Irradiation (TBI) in preparation for Hematopoietic Stem Cell Transplantation (HSCT) are at risk for Growth Hormone Deficiency (GHD), which sometimes severely compromises their Final Height (FH). To better represent the impact of such therapies on growth we apply a mathematical model, which accounts both for the gompertzian-like growth trend and the hormone-related 'spurts', and evaluate how the parameter values estimated on the children undergoing TBI differ from those of the matched normal population. METHODS: 25 patients long-term childhood lymphoblastic and myeloid acute leukaemia survivors followed at Pediatric Onco-Hematology, Stem Cell Transplantation and Cellular Therapy Division, Regina Margherita Children's Hospital (Turin, Italy) were retrospectively analysed for assessing the influence of TBI on their longitudinal growth and for validating a new method to estimate the GH therapy effects. Six were treated with GH therapy after a GHD diagnosis. RESULTS: We show that when TBI was performed before puberty overall growth and pubertal duration were significantly impaired, but such growth limitations were completely reverted in the small sample (6 over 25) of children who underwent GH replacement therapies. CONCLUSION: Since in principle the model could account for any additional growth 'spurt' induced by therapy, it may become a useful 'simulation' tool for paediatricians for comparing the predicted therapy effectiveness depending on its timing and dosage.


Assuntos
Crescimento/efeitos da radiação , Leucemia/cirurgia , Irradiação Corporal Total , Adolescente , Criança , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Lactente , Leucemia/radioterapia , Masculino , Estudos Retrospectivos , Condicionamento Pré-Transplante
11.
Int J Radiat Oncol Biol Phys ; 88(2): 292-300, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24239386

RESUMO

PURPOSE: To compare quality of survival in "standard-risk" medulloblastoma after hyperfractionated radiation therapy of the central nervous system with that after standard radiation therapy, combined with a chemotherapy regimen common to both treatment arms, in the PNET4 randomised controlled trial. METHODS AND MATERIALS: Participants in the PNET4 trial and their parents/caregivers in 7 participating anonymized countries completed standardized questionnaires in their own language on executive function, health status, behavior, health-related quality of life, and medical, educational, employment, and social information. Pre- and postoperative neurologic status and serial heights and weights were also recorded. RESULTS: Data were provided by 151 of 244 eligible survivors (62%) at a median age at assessment of 15.2 years and median interval from diagnosis of 5.8 years. Compared with standard radiation therapy, hyperfractionated radiation therapy was associated with lower (ie, better) z-scores for executive function in all participants (mean intergroup difference 0.48 SDs, 95% confidence interval 0.16-0.81, P=.004), but health status, behavioral difficulties, and health-related quality of life z-scores were similar in the 2 treatment arms. Data on hearing impairment were equivocal. Hyperfractionated radiation therapy was also associated with greater decrement in height z-scores (mean intergroup difference 0.43 SDs, 95% confidence interval 0.10-0.76, P=.011). CONCLUSIONS: Hyperfractionated radiation therapy was associated with better executive function and worse growth but without accompanying change in health status, behavior, or quality of life.


Assuntos
Neoplasias Cerebelares/radioterapia , Função Executiva/efeitos da radiação , Crescimento/efeitos da radiação , Nível de Saúde , Meduloblastoma/radioterapia , Qualidade de Vida , Adolescente , Fatores Etários , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Comportamento/efeitos da radiação , Neoplasias Cerebelares/tratamento farmacológico , Criança , Pré-Escolar , Terapia Combinada/métodos , Fracionamento da Dose de Radiação , Emprego/estatística & dados numéricos , Europa (Continente) , Função Executiva/fisiologia , Feminino , Seguimentos , Audição/efeitos da radiação , Terapia de Reposição Hormonal/métodos , Humanos , Masculino , Meduloblastoma/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde , Inquéritos e Questionários , Sobreviventes , Adulto Jovem
13.
Pediatr Endocrinol Rev ; 8(1): 6-17, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21037539

RESUMO

Tumors of the central nervous system, the most common solid tumors of childhood, are a major source of cancer-related morbidity and mortality in children. Survival rates have improved significantly following treatment for childhood brain tumors, with this growing cohort of survivors at high risk of adverse medical and late effects. Endocrine morbidities are the most prominent disorder among the spectrum of longterm conditions, with growth hormone deficiency the most common endocrinopathy noted, either from tumor location or after cranial irradiation and treatment effects on the hypothalamic/pituitary unit. Deficiency of other anterior pituitary hormones can contribute to negative effects on growth, body image and composition, sexual function, skeletal health, and quality of life. Pediatric and adult endocrinologists often provide medical care to this increasing population. Therefore, a thorough understanding of the epidemiology and pathophysiology of growth failure as a consequence of childhood brain tumor, both during and after treatment, is necessary and the main focus of this review.


Assuntos
Neoplasias Encefálicas/terapia , Hormônio do Crescimento/deficiência , Crescimento/fisiologia , Sistema Hipotálamo-Hipofisário/efeitos da radiação , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Feminino , Gonadotropinas/metabolismo , Crescimento/efeitos dos fármacos , Crescimento/efeitos da radiação , Humanos , Lactente , Masculino , Radioterapia/efeitos adversos
14.
Chronobiol Int ; 27(9-10): 1715-34, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20969519

RESUMO

Continuous light is a common practice in salmon farming, where it is used to enhance growth, induce smoltification, and regulate puberty. However, knowledge about how different tissues receive information about daylength is limited. The aim of the present study was to evaluate the daily expression of clock (Per1-like, Cry2, and Clock), the nuclear transcription factor (peroxisome proliferator-activated receptor, PPAR; CCAAT/enhancer binding protein, C/EBP), and the endoplasmic reticulum (ER) stress (protein disulfide isomerase associated 3, PDIA3) genes in the pineal gland, brain, and liver of Atlantic salmon postsmolts reared under 12-h light:12-h dark (LD) regimes or under continuous light (LL) for 6 wks following transfer to seawater. All measured clock mRNAs displayed daily variations in one or more organs under LD, as well as plasma levels of melatonin. Similar variations were noted in the liver c/ebpα, pineal c/ebpδ, and pdia3 mRNAs. Under LL, the clock and nuclear transcription factor mRNAs did not show any daily variation in the studied organs, with the exception of pineal pdia3. Furthermore, LL had the opposite effect on the levels of melatonin and cortisol, as observed by the increase in pineal Clock, Per2, pparα, and c/ebpα and c/ebpδ mRNAs and decrease in liver Clock, Per2, and pparα mRNAs compared to those under LD. The present findings show that the expression of clock genes is affected by the light across organs and that there is a relation between PPAR, C/EBP, and clock mRNAs; however, the functional role of the individual nuclear transcription factors related to this observation remains to be established in the pineal gland and liver. (Author correspondence: Tihu@nifes.no ).


Assuntos
Proteínas CLOCK/genética , Hidrocortisona/sangue , Iluminação , Melatonina/sangue , Proteínas Circadianas Period/genética , Salmo salar/genética , Animais , Encéfalo/fisiologia , Criptocromos/genética , Primers do DNA , Crescimento/efeitos da radiação , Hidrocortisona/efeitos da radiação , Fígado/fisiologia , Melatonina/efeitos da radiação , Muda/fisiologia , Glândula Pineal/fisiologia , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Salmo salar/sangue , Salmo salar/crescimento & desenvolvimento , Estações do Ano
15.
Can Fam Physician ; 55(10): 988-91, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19826155

RESUMO

QUESTION: One of my patients was incidentally found to be pregnant after completion of radiotherapy for Hodgkin lymphoma. What are the possible effects that I should discuss with her before she makes a final decision regarding continuation of her pregnancy? ANSWER: Radiotherapy might not be an absolute contraindication in pregnant women who are diagnosed with cancer located in areas remote from the pelvis. However, the fetal exposure should be carefully estimated, and the known dose-response information has to be discussed individually to allow informed decisions to be made.


Assuntos
Feto/efeitos da radiação , Doença de Hodgkin/radioterapia , Complicações Neoplásicas na Gravidez/radioterapia , Efeitos Tardios da Exposição Pré-Natal , Adulto , Pré-Escolar , Feminino , Crescimento/efeitos da radiação , Humanos , Achados Incidentais , Gravidez , Dosagem Radioterapêutica
16.
Toxicol Ind Health ; 25(7): 479-87, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19783573

RESUMO

To investigate prenatal and post-natal effects of extremely low frequency (ELF) electric field (EF) on growth and pubertal development, pregnant Wistar rats were randomly distributed among three groups. The pregnant rats of the prenatal group were exposed to 24-hour EF at 50 Hz EF 10 kV/min during pregnancy and their subsequent randomly selected female pups continued to be exposed until puberty. The post-natal group was unexposed to EF during pregnancy, but randomly selected female pups from this group were exposed to EF between delivery and puberty at the same doses and duration as the prenatal group. The third group was a sham-exposed group. The mean birth weight and weight gain of the pups during study period were found significantly reduced in prenatal group than post-natal and sham-exposed groups (p < 0.001). No difference could be found among the three groups for body weight at puberty (p > 0.05). The mean age at vaginal opening and estrous were significantly higher at prenatal group than post-natal and sham-exposed groups (p < 0.001). Serum insulin-like growth hormone-1 (IGF-1) levels were found significantly reduced in prenatal exposure group compared with the other two groups (p < 0.001). There was no difference for birth weight, weight gain, the mean age at vaginal opening and estrous and IGF-1 levels between post-natal and sham-exposed groups (p > 0.05). There was also no difference for FSH, LH and E2 levels at puberty among the three groups (p > 0.05). Histological examination revealed that both the prenatal and post-natal groups had the evidence of tissue damage on hypothalamus, pituitary gland and ovaries. In conclusion, early beginning of prenatal exposure of rats to 24 hours 50 Hz EF at 10 kV/m until puberty without magnetic field (MF) resulted in growth restriction, delayed puberty and reduced IGF-1 levels in female Wistar rats. These effects probably associated with direct toxic effects of EF on target organs. Post-natal exposure to EF at similar doses and duration seems to be less harmful on target organs. Post-natal exposure to EF at similar doses and duration seems to be less harmful.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Crescimento/efeitos da radiação , Fator de Crescimento Insulin-Like I/efeitos da radiação , Animais , Feminino , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Distribuição Aleatória , Ratos , Ratos Wistar , Estatísticas não Paramétricas
17.
Med Pr ; 60(1): 43-50, 2009.
Artigo em Polonês | MEDLINE | ID: mdl-19603696

RESUMO

This paper presents the influence of natural and artificial electromagnetic fields (EMF) on fauna and flora. The mechanisms of Earth's magnetic field detection and the use of this skill by migratory animals to faultlessly reach the destination of their travel are discussed, as well as the positive effects of electric and magnetic fields on plants relative to their physiology, yielding and health. EMF influence on social insects and animal organisms, including possible DNA damages and DNA repair systems, is presented. The influence of high frequency electromagnetic fields on birds nesting is also discussed.


Assuntos
Comportamento Animal/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental/efeitos adversos , Plantas/efeitos da radiação , Animais , Crescimento/efeitos da radiação , Doses de Radiação , Fatores de Risco
18.
Nat Cell Biol ; 11(5): 604-15, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19363488

RESUMO

The accumulation of stochastic DNA damage throughout an organism's lifespan is thought to contribute to ageing. Conversely, ageing seems to be phenotypically reproducible and regulated through genetic pathways such as the insulin-like growth factor-1 (IGF-1) and growth hormone (GH) receptors, which are central mediators of the somatic growth axis. Here we report that persistent DNA damage in primary cells from mice elicits changes in global gene expression similar to those occurring in various organs of naturally aged animals. We show that, as in ageing animals, the expression of IGF-1 receptor and GH receptor is attenuated, resulting in cellular resistance to IGF-1. This cell-autonomous attenuation is specifically induced by persistent lesions leading to stalling of RNA polymerase II in proliferating, quiescent and terminally differentiated cells; it is exacerbated and prolonged in cells from progeroid mice and confers resistance to oxidative stress. Our findings suggest that the accumulation of DNA damage in transcribed genes in most if not all tissues contributes to the ageing-associated shift from growth to somatic maintenance that triggers stress resistance and is thought to promote longevity.


Assuntos
Dano ao DNA/fisiologia , Crescimento/fisiologia , Longevidade/fisiologia , Transcrição Gênica/genética , Envelhecimento/fisiologia , Estruturas Animais/metabolismo , Animais , DNA/efeitos da radiação , Reparo do DNA/fisiologia , Perfilação da Expressão Gênica , Crescimento/efeitos da radiação , Humanos , Longevidade/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Neoplasias/etiologia , Neoplasias/genética , Estresse Oxidativo/fisiologia , Progéria/genética , Progéria/metabolismo , RNA Polimerase II/metabolismo , Ratos , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo , Estresse Fisiológico/fisiologia , Transcrição Gênica/efeitos da radiação , Raios Ultravioleta
19.
J Exp Biol ; 212(Pt 5): 662-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19218517

RESUMO

Many terrestrial plants form complex morphological structures and will alter these growth patterns in response to light direction. Similarly reef building corals have high morphological variation across coral families, with many species also displaying phenotypic plasticity across environmental gradients. In particular, the colony geometry in branching corals is altered by the frequency, location and direction of branch initiation and growth. This study demonstrates that for the branching species Acropora pulchra, light plays a key role in axial polyp differentiation and therefore axial corallite development--the basis for new branch formation. A. pulchra branches exhibited a directional growth response, with axial corallites only developing when light was available, and towards the incident light. Field experimentation revealed that there was a light intensity threshold of 45 micromol m(-2) s(-1), below which axial corallites would not develop and this response was blue light (408-508 nm) dependent. There was a twofold increase in axial corallite growth above this light intensity threshold and a fourfold increase in axial corallite growth under the blue light treatment. These features of coral branch growth are highly reminiscent of the initiation of phototropic branch growth in terrestrial plants, which is directed by the blue light component of sunlight.


Assuntos
Antozoários/crescimento & desenvolvimento , Luz , Fototropismo/fisiologia , Animais , Antozoários/efeitos da radiação , Crescimento/efeitos da radiação
20.
J Exp Zool A Ecol Genet Physiol ; 311(2): 73-9, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18828146

RESUMO

We examined the effects of different light wavelengths-blue, green, and red-on the somatic growth of the barfin flounder Verasper moseri, a flatfish. The light sources used were fluorescent lamps and a combination of daylight and fluorescent lamps that produced ambient light. These light sources were filtered using blue, green, or red filters. During the experiments, the fish were reared in indoor tanks with running seawater of natural temperature and fed with commercial pellets twice daily until satiety. The tanks were white in color. Fish were exposed to constant light emitted from the fluorescent lamps (9:15, light:dark; 08:00-17:00, light) for 14 weeks from October or September to January or to ambient light with a 14-week natural photoperiod from September to December. The wavelengths that were filtered from the fluorescent lamp light modified the growth of the fish, i.e., fish reared under green or blue light exhibited a greater total length (TL; P<0.01) and body weight (BW; P<0.01) than those reared under red light. In contrast, in the case of fish exposed to filtered ambient light, fish reared under green light exhibited a greater TL (P<0.01) and BW (P<0.01) than fish exposed to other wavelengths-blue-, red-, and nonfiltered ambient light. Our results indicate that flounder growth was modified by certain wavelengths, namely, green and red light, which had growth-stimulating and growth-inhibiting effects, respectively.


Assuntos
Linguado/crescimento & desenvolvimento , Crescimento/efeitos da radiação , Luz , Análise de Variância , Animais , Filtração , Japão , Fotoperíodo , Fatores de Tempo
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