The absence of maternal pineal melatonin rhythm during pregnancy and lactation impairs offspring physical growth, neurodevelopment, and behavior

Maternal melatonin provides photoperiodic information to the fetus and thus influences the regulation and timing of the offspring's internal rhythms and preparation for extra-uterine development. There is clinical evidence that melatonin deprivation of both mother and fetus during pregnancy, and of the neonate during lactation, results in negative long-term health outcomes. As a consequence, we hypothesized that the absence of maternal pineal melatonin might determine abnormal brain programming in the offspring, which would lead to long-lasting implications for behavior and brain function. To test our hypothesis, we investigated in rats the effects of maternal melatonin deprivation during gestation and lactation (MMD) to the offspring and the effects of its therapeutic replacement. The parameters evaluated were: (1) somatic, physical growth and neurobehavioral development of pups of both sexes; (2) hippocampal-dependent spatial learning and memory of the male offspring; (3) adult hippocampal neurogenesis of the male offspring. Our findings show that MMD significantly delayed male offspring's onset of fur development, pinna detachment, eyes opening, eruption of superior incisor teeth, testis descent and the time of maturation of palmar grasp, righting reflex, free-fall righting and walking. Conversely, female offspring neurodevelopment was not affected. Later on, male offspring show that MMD was able to disrupt both spatial reference and working memory in the Morris Water Maze paradigm and these deficits correlate with changes in the number of proliferative cells in the hippocampus. Importantly, all the observed impairments were reversed by maternal melatonin replacement therapy. In summary, we demonstrate that MMD delays the appearance of physical features, neurodevelopment and cognition in the male offspring, and points to putative public health implications for night shift working mothers

Repetibilidade em características biométricas do fruto de macaúba Repeatability in biometric characteristics of macaw palm fruit

Estimativas do coeficiente de repetibilidade têm sido utilizadas no estudo de caracteres de várias espécies de palmeiras, auxiliando na definição do número e período adequado de avaliações dos genótipos para maior eficiência dos programas de melhoramento. Para macaúba, não há relatos de estudos dessa natureza. Nesse contexto, faz-se importante a determinação do coeficiente de repetibilidade das seguintes características biométricas dos frutos: peso do fruto, volume do fruto, diâmetro equatorial do fruto, peso da amêndoa, volume da amêndoa, diâmetro da amêndoa e espessura do endocarpo; e a determinação do número mínimo de avaliações para um eficiente processo de seleção e avaliação de subamostras de macaúba. O trabalho foi desenvolvido no Departamento de Fitotecnia da Universidade Federal de Viçosa, analisando-se 145 subamostras de macaúba, provenientes de coletas realizadas nos estados de Minas Gerais, São Paulo, Mato Grosso do Sul, Pará, Maranhão e Pernambuco. Houve diferença significativa para todas as características analisadas e observou-se concordância nas magnitudes dos coeficientes de repetibilidade de cada característica, obtidos pelos diferentes métodos. No entanto, os coeficientes de repetibilidade variam entre as oito características, de 0,68 a 0,99, observados para a característica espessura do endocarpo e volume da amêndoa, respectivamente. As estimativas dos coeficientes de determinação obtidas a partir das 10 repetições para as oito características e pelos quatro métodos foram superiores a 95%. A avaliação de quatro frutos é suficiente para compreensão das características estudadas das subamostras de macaúba com 90% de acurácia.<br>Estimates of repeatability coefficient have been used in character study of several species of palms, helping to define the number and appropriate period of assessment of genotypes to increase the efficiency of breeding programs. For macaw palm there are no reports of such studies. In this context it is important to determine the repeatability coefficient of the following biometric characteristics of fruits: fruit weight, fruit volume, equatorial diameter of the fruit, kernel weight, kernel volume, equatorial diameter of de kernel, and thickness of the endocarp, and the determination of the minimum number of ratings for an efficient selection process and evaluation of macaw palm subsamples. The study was conducted at the Department of Plant Science, Federal University of Viçosa, and 145 macaw palm subsamples were analyzed, from collections made in the states of Minas Gerais, São Paulo, Mato Grosso do Sul, Pará, Maranhão and Pernambuco. There were significant differences for all traits analyzed, and there was agreement on the magnitude of repeatability coefficients of each feature obtained by different methods. However, the repeatability coefficients ranging between eight characteristics, from 0.68 to 0.99, and were observed for feature endocarp thickness and volume of kernel, respectively. The coefficient of determination obtained from 10 repetitions for the eight features and the four methods were superior to 95%. The evaluation of four fruits is sufficient to assess the traits of macaw palm subsamples with 90% accuracy