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Abstract: Patagonian red octopus, Enteroctopus megalocyathus, is a merobenthic octopus whose paralarvae have been successfully cultured up to juvenile octopuses. At present, high mortality during the paralarval period prevents the scaling from experimental rearing to commercial aquaculture. The aim of the study was to determine upper (CTMax) and lower (CTMin) thermal tolerance, acclimation response ratio (ARR) and thermal tolerance polygon of paralarvae from different culture conditions and subjected to seven acclimation temperatures (6, 8, 10, 12, 14, 16, 18°C) during the first 5 days of paralarval life. Culture conditions were two types of egg incubation (maternal care and artificial incubators) and two feeding regimes (fed or starved). Fed paralarvae showed thermal preferendum, while unfed paralarvae preferred much higher temperatures than those of acclimation. CTMin and CTMax increased along with the acclimation temperature. Lower values of ARR were obtained in paralarvae from artificial incubation, with this type of paralarva showing the least adaptability to thermal changes. Starved paralarvae showed the lowest values for thermal tolerance range (TTR) and smaller areas of thermal polygon than fed paralarvae. Rearing temperatures above 16°C may be considered suboptimal to paralarvae and affected by the conditions during the embryonic incubation. Rearing temperatures below 8°C may be considered suboptimal for all hatched paralarvae. Therefore, the other temperatures within this range could be used in the context of improving the culture management of paralarvae. [ABSTRACT FROM AUTHOR]

We propose two hypotheses to explain the inexistence of adequate prepared diet for Octopus maya at this date: Hypothesis 1 is related to changes in protein structure during protein cooking, which affects the digestibility. Hypothesis 2 is related to changes on nutritional characteristics during ingredient process, which affects the nutritional composition of diet. To test hypothesis 1, experiments one and two were directed to determine if protein cooking reduces digestibility and growth of animals when compared to fresh or lyophilized protein sources. For hypothesis 2, three experiments were conducted, testing seven different dietary protein sources offered in isolation or combined in artificial diets fed to O. maya. Results demonstrated that the diets that promoted growth were the ones based on fresh crab paste, and both lyophilized crab and squid tentacles paste. In consequence hypothesis 1 was accepted. The cooking process also changed nutritional characteristics of protein sources, affecting the growth of O. maya. Results obtained when squid and crab were mixed suggest that nutritional requirements of octopuses were covered with that diet in similar forms compared to when using fresh or lyophilized crab, also confirming hypothesis 2. Based on growth rates obtained, we can conclude that nutritional requirements of O. maya must be between 80% and 86% Protein (P), 5.1-5.6% Lipids and a protein: energy ratio between (P/E) 38.9 and 42.2 g MJ−1. [ABSTRACT FROM AUTHOR]

The article discusses pectoralis quartus muscle where a rare anatomical variant. Topics include the pectoral musculature is included in the radiologic exams for breast cancer screening; it is a segmented portion of the pectoralis major muscle that runs below or beside the inferior fibers of the pectoralis major muscle; and volume rendering 3D reconstructed chest computed tomography.

The impact of dietary fenugreek (FN) supplementation on growth performance, physio‐metabolic enzyme response, and antioxidant enzyme activities in hybrid African catfish (Clarias gariepinus ♀ × Heterobranchus bidorsalis ♂) was investigated in this study. Five isonitrogenous diets (38% crude protein) were developed and fed to the fish for 60 days. The FN was incorporated into the diets at 0%, 0.5%, 1.0%, 1.5%, and 2%. Two hundred twenty‐five fingerlings of hybrid African catfish (average weight 4.01 g ± 0.02) were used for the study and randomly distributed to five dietary groups in triplicate. FN supplementation improved growth responses and survival rates; the dietary groups considerably (p < 0.05) outperformed the control group. FN‐based diets considerably increased the carcass protein content (p = 0.020) and improved protein retention (p = 0.015). FN supplementation markedly (p < 0.001) and dose‐dependently reduced the carcass's lipid content and substantially (p < 0.001) increased the levels of metabolic enzymes. The fish antioxidant capacity was significantly enhanced (p < 0.001), and hepatic stress enzymes were greatly (p < 0.001) lowered in FN‐based diets. In summary, the second‐order polynomial regression analysis indicates that the optimal dose of FN supplementation to improve hybrid catfish growth without negatively affecting the fish's physio‐metabolic response or overall wellbeing is 1% dietary inclusion level. [ABSTRACT FROM AUTHOR]

The octopuses are an emergent group for marine aquaculture diversification. One of the main factors limiting their commercial production is the absence of pelleted or extruded diets that are capable of promoting adequate survival and growth. We tested a pelleted diet with ingredients dried at 40°C and a semi‐moist diet based on of raw ingredients (control diet) on the growth performance and activity of digestive enzymes in Octopus americanus subadults. Compared to the semi‐moist diet, the pelleted diet was well accepted and presented greater stability in the water and lower leaching. Both diets provided similar growth, survival, feed efficiency and conversion rates, although the total ingestion rate and protein and energy intake rates were higher in octopuses that were fed the semi‐moist diet. Furthermore, the pelleted diet stimulated higher activity of acidic proteolytic enzymes, and chymotrypsin activities in the caecum as a physiological response to improve nutrient absorption and assimilation. Therefore, such a diet could be utilized as a starting point to design formulated diets for octopus. [ABSTRACT FROM AUTHOR]

Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris ( Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg−1 DW, and it decreased with increasing fasting days. The non-essential amino acids content was higher (486.18 ± 11.08 g kg−1 protein) than essential amino acids (425.82 ± 9.15 g kg−1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx ( Asp, Asn), Glx ( Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting. [ABSTRACT FROM AUTHOR]

The present study was designed to assess the performance of the freshwater prawn Macrobrachium tenellum in optimal and sub‐optimal dissolved oxygen conditions, considering increasing environmental pressures. Thermal tolerance and thermal metabolic scope (TMS) with related integrated biomarker response (IBR) were measured in prawns exposed to normoxia (80% air saturation), mild (40% air saturation) and severe hypoxia (25% air saturation) at three exposure time points (10, 20 and 30 days). Effects of hypoxia on thermal tolerance were not detectable over time; they were perhaps masked by hyperventilation, or by an increase or diversion of haemolymph processes. After 30 days, TMS was 11% higher in mild hypoxia compared with normoxia, while it was 64% lower in severe hypoxia, indicating the loss of aerobic metabolism capacity during the latter. Mild‐hypoxia prawns maintained a high IBR over time, supported by antioxidant enzyme activities (mainly superoxide dismutase), which helped avoid the serious oxidative damage (proteins and lipids) seen in severe hypoxia animals, as well as lower acetylcholinesterase activity that indicated failure of communication between the nervous and locomotor systems. Our results documented a high tolerance by M. tenellum to mild‐hypoxia events, which should be further tested under seasonal and extreme habitat/tank temperatures. [ABSTRACT FROM AUTHOR]

This study assessed the effect of starvation on survival and nutritional status of newborn juveniles H. erectus (<10 days) to optimize rearing protocols, thereby helping to reduce wildlife exploitation. Maximum starvation time (MST) was estimated through the survival of juveniles continuously starved from birth. Resistance to starvation and the effect of food re‐introduction after 1, 2, 4 and 6 days of starvation on survival and metabolite concentrations (total proteins, total lipids, acylglycerides, cholesterol, glucose) were also determined. Survival amongst continuously starved animals decreased from 6.6 ± 0.5 to 0% from days 9 to 10 of starvation. Seahorses under different starvation–refeeding treatments all had 100% survival up to day 5 of experiments. After 10 days, however, a 4‐day starvation period followed by refeeding showed negative effects with <50% survival. During continuous starvation, lipids were the first energy reserve used to maintain basal metabolism, followed by proteins. Except for cholesterol, all metabolite concentrations differed between continuous starvations and feeding. Despite high seahorse survival after 5 days in the absence of food, the recovery of the metabolic status is possible after a starvation period of no more than 2 days, since irreversible physiological changes compromising the ultimate survival of the organisms take place after this time. [ABSTRACT FROM AUTHOR]

The artciel discusses the study of the Clinical and imaging features of dermatofibrosarcoma protuberans in the breast. Topics discussed include Dermatofibrosarcoma protuberans (DFSP) is a soft tissue sarcoma of dermal fibroblastic origin that normally occurs in middle-aged adults; and the occurrence of this tumor in the breast is very rare, and only a few case reports have been described in the literature.

One of the major problems involved in the controlled cultivation of Patagonian red octopus ( Enteroctopus megalocyathus) is its long embryonic period ranging between 150-176 days, after which the hatching of planktonic paralarvae is achieved. The effect of temperature on the incubation of E. megalocyathus eggs was studied with the aim of establishing if a temperature higher than 12°C is effective to accelerate the embryonic development without altering their morphological and physiological conditions. Fertilized eggs obtained under controlled conditions at 11°C ± 0.1 were randomly distributed in 12 water baths of 30 L at 4 temperatures: 12, 14, 15 and 16°C ± 0.1°C. The experiment lasted until egg hatching occurred.The embryo growth rate was accelerated at 15-16°C, so the time spent in embryonic development can be reduced in 15% when compared with embryo development obtained from eggs incubated at 12°C. The embryos showed no significant differences in the final survival and were morphometrically similar in all stages of development at all temperatures. The increase in temperature from 12 to 16°C, even if it allowed a better growth, had high metabolic costs for embryos of E. megalocyathus. The activities of lipases and proteases were affected by interaction between temperature and the embryo stage, with high lipase activity observed in embryos of stage XV incubated at high temperatures and the highest levels of trypsin and chymotrypsin in stage XX at 14°C. The results suggest that 15°C could be the limit temperature to increase growth. [ABSTRACT FROM AUTHOR]

The effects of feeding two alternative live prey Hyalella azteca (freshwater gammarids) and Hyale media (marine gammarids) to Octopus maya hatchlings were compared with feeding adult Artemia sp., traditionally used during the first weeks of the life cycle. Hatchlings were fed ad libitum these three live preys during the first 15 days, and a paste elaborated with fresh squid and shrimp during the next 15 days when hatchling can be fed prepared diets. Weight (g) and specific growth rates (% day−1) were determined every 15 days. Octopus maya hatchlings fed with marine gammarids grew larger (6.9 ± 0.2% day−1) compared with hatchlings fed Artemia sp. or freshwater gammarids (4.8 ± 0.2% and 5.0 ± 0.3% day−1 respectively). Survival was also higher (92.2 ± 6.8%) for hatchlings fed marine gammarids, than for those fed Artemia sp. (74.5 ± 23.8%) or freshwater gammarids (41.2 ± 21.2%). The content of acylglycerides, cholesterol and proteins in O. maya fed marine gammarids suggested a better nutrient assimilation by the hatchlings. Also, polyunsaturated fatty acids levels ( EPA and DHA) were more abundant in marine gammarids, possibly contributing to the higher growth rates observed. This is the first study revealing a successful use of marine gammarids as alternative prey for octopus hatchlings culture. [ABSTRACT FROM AUTHOR]

The effects of diet freezing on the growth, survival and biochemical composition of the diets and juvenile spider crabs ( Maja brachydactyla) were studied. Fresh and frozen (at −20 °C for 21 days) mussels, Mytilus edulis, were used as food. Two experiments were conducted and in each, spider crabs were placed in individual trays. During experiment I, 40 juvenile spider crabs (2 months old) were used. Twenty animals (9 ± 2 mg) were fed fresh mussels, and 20 animals (8 ± 2 mg) were fed frozen mussels. Spider crabs fed fresh mussels grew larger than the ones fed frozen mussels (304.0 ± 118.0 and 70.0 ± 40.1 mg respectively). During experiment II, 16 juvenile spider crabs (5 months old) were used. Eight animals (3.4 ± 0.8 g) were fed fresh mussel and eight animals (4.1 ± 1.3 g) were fed frozen mussel. Spider crabs fed with fresh mussels were larger than the ones fed with frozen mussels (92.5 ± 41.7 and 41.5 ± 17.7 g respectively). There were no significant differences in the protein, amino acids and fatty acid composition between fresh and frozen mussels. The freezing procedure makes mussels less adequate for the culture of 2-month-old early juveniles of M. brachydactyla up to 5 months, although they promoted acceptable growth and good survival in older animals (>5 months old). [ABSTRACT FROM AUTHOR]

As a function of the water quality provided by square, circular and oval experimental ponds, the growth, survival and oxygen requirements in epibenthic postlarvae of Farfantepenaeus aztecus were analysed in relation to their routine metabolism and apparent heat increment. Temperature, oxygen concentration, pH and salinity were measured daily in two experimental ponds of each shape. The postlarvae oxygen consumption during two 24-h cycles, their growth, physiological condition and survival and the productivity in the ponds were estimated. Low values of pH, oxygen concentration and phytobenthos productivity, and reduced postlarvae relative growth and survival were observed in the square ponds. We suggest that the latter results from a deficient water circulation related to the effect of the pond's shape on dissolved oxygen levels and, consequently, on growth and survival. The postlarvae routine metabolism, including feeding, varied between 1.91 and 2.25 mg O2 h−1 g−1 wet weight, whereas the minimum oxygen concentration needed in the ponds is approximately 4.25 mg O2 L−1. These conditions were achieved in the oval ponds concurrent with higher survival and growth values, in which individuals distributed randomly, for which we suggest that oval-shaped ponds could be the most adequate for the culture of this and other penaeid species. [ABSTRACT FROM AUTHOR]