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Early life, covering childhood and adolescence in humans, is an important period of brain development and maturation. Experimental works in rodents have shown that high-caloric diets are particularly detrimental to young rats, affecting cognition. We studied the effects of two different high-caloric diets, prevalent in human adolescents, on male Wistar rats aged 4 weeks at the beginning of the experiment. Rats were randomly allocated to control (C, n = 10), high-sugar diet (HS, n = 10) and cafeteria diet (CAF, n = 10) groups and fed accordingly for 8 weeks. At the end of this period, behavioral tests were performed to analyze (1) anxiety behavior in the elevated plus-maze and open field tests, (2) learning and memory processes in the Morris water maze and novel object recognition test, (3) fear response in the fear conditioning test, and (4) depression state in the forced swim test. We also examined neurogenesis in the dentate gyrus using the marker of neuroproliferation doublecortin (DCX). Our results show that CAF rats have impaired spatial learning and memory and increased anxiety, without changes in the remaining aspects of behavior, associated with a reduction of the total number of DCX-immunoreactive cells in the subgranular layer of the dentate gyrus. Conversely, HS rats displayed no changes in behavior and neurogenesis. These data demonstrate that diets rich in saturated fats and sugar are more detrimental for juvenile rats than diets with high sugar content in what concerns their effects in anxiety-related behaviors, spatial learning and memory, and neurogenesis. These findings may help explain the cognitive disturbances observed in obese human adolescents, who consume high-caloric diets., (Copyright © 2018 Elsevier Inc. All rights reserved.)

It is widely known that caloric restriction (CR) has benefits on several organic systems, including the central nervous system. However, the majority of the CR studies was performed in adult animals and the information about the consequences on young populations is limited. In this study, we analyzed the effects of young-onset CR, started at 4weeks of age, in the number of neuropeptide Y (NPY)-containing neurons and in neurogenesis of the hippocampal formation, using doublecortin (DCX) and Ki67 as markers. Knowing that CR treatment could interfere with exploratory activity, anxiety, learning and memory we have analyzed the performance of the rats in the open-field, elevated plus-maze and Morris water maze tests. Animals aged 4weeks were randomly assigned to control or CR groups. Controls were maintained in the ad libitum regimen during 2months. The adolescent CR rats were fed, during 2months, with 60% of the amount of food consumed by controls. We have found that young-onset CR treatment did not affect the total number of NPY-immunopositive neurons in dentate hilus, CA3 and CA1 hippocampal subfields and did not change the exploratory activity and anxiety levels. Interestingly, we have found that young-onset CR might affect spatial learning process since those animals showed worse performance during the acquisition phase of Morris water maze. Furthermore, young-onset CR induced alterations of neurogenesis in the dentate subgranular layer that seems to underlie the impairment of spatial learning. Our data suggest that adolescent animals are vulnerable to CR treatment and that this diet is not suitable to be applied in this age phase., (Copyright © 2016 Elsevier Inc. All rights reserved.)

A recent revival in using cephalopods as experimental animals has rekindled interest in their biology and life cycles, information with direct applications also in the rapidly growing ornamental aquarium species trade and in commercial aquaculture production for human consumption. Cephalopods have high rates of growth and food conversion, which for aquaculture translates into short culture cycles, high ratios of production to biomass and high cost-effectiveness. However, at present, only small-scale culture is possible and only for a few species: the cuttlefish Sepia officinalis, the loliginid squid Sepioteuthis lessoniana and the octopuses Octopus maya and O. vulgaris. These four species are the focus of this chapter, the aims of which are as follows: (1) to provide an overview of the culture requirements of cephalopods, (2) to highlight the physical and nutritional requirements at each phase of the life cycle regarded as essential for successful full-scale culture and (3) to identify current limitations and the topics on which further research is required. Knowledge of cephalopod culture methods is advanced, but commercialization is still constrained by the highly selective feeding habits of cephalopods and their requirement for large quantities of high-quality (preferably live) feed, particularly in the early stages of development. Future research should focus on problems related to the consistent production of viable numbers of juveniles, the resolution of which requires a better understanding of nutrition at all phases of the life cycle and better broodstock management, particularly regarding developments in genetic selection, control of reproduction and quality of eggs and offspring., (© 2014 Elsevier Ltd All rights reserved.)