Results: 15

Photoperiodic effects in blood glucose, cortisol, hematological parameters and reproductive indexes of gift lineage reversed male tilapia

Biosci. j. (Online); 35 (6), 2019
The objective of this study was to evaluate the influence of the photoperiod on the physiological, hematological and reproductive parameters of tilapia males of the GIFT lineage. The treatments differed in the simulations of emeral photoperiods T1 = 0L: 24E T2 = 24L: 0E, T3 = 12L: 12E. Each ...

Effect of photoperiod on ovarian maturation in Cheirodon interruptus (Teleostei: Characidae)

Braz. j. biol; 79 (4), 2019
Abstract Cheirodon interruptus is a ubiquitous small characid that inhabits the Pampean region and commonly used as bait. Its vast market is supplied from the wild population causing a significant environmental impact. In this study, we assess the effect of photoperiod on ovarian maturation in order to e...

Biology of Corythucha gossypii Fabricius, 1794 (Hemiptera: Tingidae) in Ricinus communis at different temperatures and thermal requirements

Braz. j. biol; 79 (2), 2019
Abstract We studied the biology of Corythucha gossypii in Ricinus communis under different temperatures in climatic chambers adjusted at 20, 23, 25, and 28 °C, 60 ± 10% relative humidity, and a 12-h photoperiod. The development period and viability of eggs, the development period and survival rate of ...

Effects of light-dark cycle on the spatial distribution and feeding activity of fish larvae of two co-occurring species (Pisces: Hypophthalmidae and Sciaenidae) in a Neotropical floodplain lake

Braz. j. biol; 78 (4), 2018
Abstract Most studies on mechanisms regulating fish larvae processes have focused on assessing the isolated effects of food distribution and feeding behavior. However, in natural ecosystems, fish larvae may strongly interact with zooplankton organisms in an array of complex, direct and indirect interdepe...

Phenology of Guarea macrophylla Vahl (Meliaceae) in subtropical riparian forest in southern Brazil

Braz. j. biol; 78 (2), 2018
Abstract Climate is one of the main factors that affect plant behavior. The phenology of Guarea macrophylla Vahl, which is a small tree used for reforestation of degraded areas, was monitored for 18 months in a riparian forest at the Schmidt Stream, Campo Bom, in the state of Rio Grande do Sul, southern ...

Bipolar disorders: is there an influence of seasonality or photoperiod?

Objective: To increase understanding of the influence of photoperiod variation in patients with bipolar disorders. Methods: We followed a sample of Italian bipolar patients over a period of 24 months, focusing on inpatients. All patients admitted to the Psychiatric Inpatient Unit of San Luigi Gonzaga Ho...

The influence of a light and dark cycle on the egg laying activity of Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae)

Mem. Inst. Oswaldo Cruz; 113 (4), 2018
BACKGROUND The epidemiological importance of the mosquito Aedes aegypti as a vector of multiple human pathogens has generated a growing number of studies on the physiology and behaviour of its blood-feeding females. The activity of oviposition is one of the critical elements contributing to the expansion...

Environmental drivers on leaf phenology of ironstone outcrops species under seasonal climate

An. acad. bras. ciênc; 89 (1), 2017
ABSTRACT Banded iron formations (BIF) have a particular vegetation type and provide a good model system for testing theories related to leaf phenology, due to unique stressful environmental conditions. As a consequence of the stressful conditions of BIF environment, we hypothesize that most species would...

Physical characterization of Rhipsalis (Cactaceae) fruits and seeds germination in different temperatures and light regimes

Braz. j. biol; 76 (2), 2016
Abstract The germination characteristics of the native cactus species are poorly known, being the temperature and the light the factors that the most interferes in that process. Thus, the objective of the present work was to characterize the fruits and evaluate the influence of the temperature and the li...