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Uno de los problemas principales del estudio de la violencia es la falta de una definición precisa que dé cuenta de la multiplicidad de formas en las que ésta se presenta o, cuando menos, señale sus características más importantes y comunes. Al analizar los efectos de la violencia sobre la salud de la mujer se obtiene que las expone a un mayor riesgo de enfermedades físicas y mentales por lo que aumenta el interés en estudiar algunos marcadores que orienten su confirmación diagnóstica. Con la investigación se pretende estudiar los resultados que abordan esta problemática desde distintos ámbitos promoviendo una mirada integral y multidisciplinaria sobre la violencia, fenómeno con múltiples implicaciones sociales y culturales que influyen a la aplicación de tales políticas y medidas de control sanitario y judicial en la República del Ecuador. es necesario no solo identificar y tener claro las formas en que se materializa la violencia entre las personas puesto que el desconocimiento teórico de la misma puede llevar a tener consecuencias graves en el desarrollo físico y psicológico del ser humano cuyo desenlace puede resultar desde una disfuncionalidad del adulto hasta la muerte, ya sea en mujeres gestantes, el feto o en el adulto deprimido. El marco legal reconoce la existencia de esta problemática, tanto así que los esfuerzos al legislar resultan en un conjunto de artículos y leyes que busca consecuencias judiciales para quien las cometa.

An 8-week feeding trial investigated the effect of Fishmeal (FM) replacement by soybean meal (SBM) and poultry by-product meal (PBM) in diets supplemented with DL-Met, MET-MET (AQUAVI

The histological structure, histochemical features, and enzymatic activity of the digestive tract of juvenile Pacific seahorse (Hippocampus ingens) are described to provide information during the cultivation of this species. Serial histological sections were stained with either hematoxylin-eosin, alcian blue-PAS, toluidine blue, Sudan black, Masson's trichome, and ninhydrin-Schiff to describe the general features and the presence of glycogen, mucopolysaccharides, lipids, muscle layers, and proteins, respectively. The enterocytes height and the mucosal villi height in the esophagus and intestines were measured. Additionally, the digestive enzymes trypsin, chymotrypsin, lipase, amylase, aminopeptidase, acid phosphatase, and alkaline phosphatase activities were recorded. The esophagus showed two distinctive regions, the anterior with numerous mucous cells secreting acid mucins and the posterior with longitudinal folds and no mucous cells. The intestine was differentiated into three regions. The anterior showed goblet cells secreting acid and neutral mucins, while the middle and posterior regions presented goblet cells secreting only acid mucins. The activity of aminopeptidase, chymotrypsin, and amylase showed low levels, while the trypsin and acid phosphatase activity levels were intermediate. Lipase and alkaline phosphatase showed the highest activities. The results point that juvenile H. ingens presents a digestive structure similar to other teleost species. The high levels of lipase suggest that juvenile H. ingens have high requirements for lipids during this stage.

The present study aimed to know the effect of the administration of Debaryomyces hansenii yeast on growth, development and skeletal deformities, through the quantification of molecular and morphophysiological indicators in longfin yellowtail larvae. Larvae from the yeast group were fed with the rotifers and Artemia metanaupli half enriched with D. hansenii (50% of live prey) and half enriched with Origreen® (50% of live prey) and were compared to control (100% Origreen®) from 5 to 30 days post-hatching (DPH). Each treatment had two methodological replicates. Studies on bone mineralization, skeletal deformities, intestinal histological analysis, digestive enzyme activity, differential gene expression (RT-qPCR) and transcriptome analysis (RNA-Seq) were performed in whole larvae. Results showed that larvae fed D. hansenii encapsulated within enriched live preys had higher survival and growth, higher intestinal mucin secretion, as well as higher activity of alkaline phosphatase, pepsin and α-amylase. The degree of bone mineralization in the cranial and caudal fin complex was higher in larvae fed D. hansenii and a lower incidence of deformities at the vertebral column was also observed. In general, the gene expression throughout the development fluctuated between the control group and the yeast treatment; however, at 30 DPH, a higher expression of the bone morphogenetic protein type 2 (bmp2), collagen type 1α1 (col1α1) and proliferating cell nuclear antigen (pcna) genes was detected in larvae fed with yeast. The transcriptomic analyses using RNA-Seq revealed that the main genes related to bone mineralization degree and digestive tract maturation, were overrepresented in the D. hansenii treatment, 1,25-dihydroxyvitamin D (3) 24-hydroxylase (cyp24), cytochrome P450 family 27 subfamily A (cyp27a), protein 5 related to the low-density lipoprotein receptor (lrp5), myocyte-specific enhancing factor 2C (mef2), enterokinase (entk), pepsin and alkaline phosphatase. Based on the results, S. rivoliana larvae supplemented with the yeast D. hansenii presented higher growth and survival, a higher degree of maturation of the digestive tract, a higher degree of bone mineralization and a reduction in skeletal deformities, for which the continuous use of yeast is recommended as a food supplement to larvae from 5 days post-hatching onwards. info:eu-repo/semantics/acceptedVersion

WOS:000591249000001; Ultra-diluted bioactive compounds have emerged as an alternative to enhance marine organism performance and to improve broodstock gonad maturation. This study evaluated for the first time the effect of three homeopathically ultra-diluted bioactive compounds (HUBC's) authorized by the health authority as medicines for humans, on the general reproductive physiology of Argopecten ventricosus, a commercially important scallop species. The experiment included three HUBC's treatments at centesimal dilution assessed in triplicate under laboratory conditions, T1: PaV-30C + PhA-30C, T2: PaV-30C + SiT-30C, and T3: ViT-30C, and a non-treated field reference group (FRG) maintained in aquaculture facilities as reference. The bioenergetics of scallop reproduction and oocyte quality increased with the three HUBC treatments, but particularly in those treated with T2. The organisms treated with T3 showed not only the highest proliferation of vitellogenic and post-vitellogenic oocytes but also the greatest oxidative damage in tissues and oocytes. In contrast, the scallops from T1 and T2 showed less oxidative damage. The results suggest that ultra-diluted formula T2 is a potential alternative to optimize A. ventricosus gonad ripening, food-nutrient management and oocyte quality because although T3 allowed accelerating the gametogenesis process, it increased oxidative damage. This study could help to improve gonad broodstock condition and larval yield of this species in hatcheries.

Domoic acid (DA), the phycotoxin responsible for amnesic shellfish poisoning (ASP), is an excitatory amino acid naturally produced by at least twenty-eight species of the bloom-forming marine diatoms Pseudo-nitzschia spp. Suspension feeders, such as bivalve mollusks, can accumulate and lengthy retain high amounts of DA in their tissues, threatening human health and leading to extensive-prolonged fishery closures, and severe economic losses. This is particularly problematic for the king scallop Pecten maximus, which retains high burdens of DA from months to years compared to other fast-depurator bivalves. Nonetheless, the physiological and cellular processes responsible for this retention are still unknown. In this work, for the first time, a novel immunohistochemical techniques based on the use of an anti-DA antibody was successfully developed and applied for DA-detection in bivalve tissues at a subcellular level. Our results show that in naturally contaminated P. maximus following a Pseudo-nitzschia australis outbreak, DA is visualized mainly within small membrane-bounded vesicles (1 – 2.5 µm) within the digestive gland cells, identified as autophagosomic structures by means of immune-electron microscopy, as well as in the mucus-producing cells, particularly those from gonad ducts and digestive tract. Trapping of DA in autophagososomes may be a key mechanism in the long retention of DA in scallops. These results and the development of DA-immunodetection are essential to provide a better understanding of the fate of DA, and further characterize DA contamination-decontamination kinetics in marine bivalves, as well as the main mechanisms involved in the long retention of this toxin in P. maximus.

Agave lechuguilla is a succulent plant species, mainly distributed in the northeast of Mexico and south of the United States of America. The main use for this plant is the fibre´s extraction (known as Tampico fibres), resulting in 15% of fibres and 85% of a by‐product waste named guishe. The lechuguilla collectors, normally incinerate the guishe, thus causing environmental contamination. Interestingly, recent studies showed that guishe contains molecules with nutritional properties, such as saponins, flavonoids and sugars. Therefore, in this work, we evaluated the effect of the crude extract of guishe as a feed additive in whiteleg shrimp diets. According to that, MS‐HPLC analysis of the extract showed the presence of saponins such as diosgenin, smilagenin, hecogenin, manogenin, tigogenin hexose, yucagenin, chlorogenin, diosgenin diglucoside and the flavonol, quercetin. After chemical analysis, the crude extract was included into an experimental diet in four levels; 0% (L0%), 0.1% (L0.1%), 0.3% (L0.3%) and 0.6% (L0.6%). Dietary incorporation of the extract was evaluated by zootechnical performance, haemolymph biochemistry, histomorphology and digestive enzyme activity of shrimps. After 5‐week feeding, the L0.3% diet showed significantly higher growth and better feed utilization among treatments. A significant increase in tubule epithelium height and tubule coverage area from hepatopancreas in shrimp under L0.3% diet compared with the control diet suggest an improvement of the health and nutritional status of the shrimp. Inclusion of L0.3% and L0.6% of the crude extract resulted in a reduction in amylase activity, without effect in glucose levels in the haemolymph. Thus, we suggest that lechuguilla guishe crude extract contains nutritional molecules that may be used as a feed additive to promote shrimp productivity.

Sex change in both directions is a novelty reported in some species of fishes belonging to seven families associated to reefs. This study demonstrated that Lythrypnus pulchellus, a small cryptobenthic haremic reef fish, is a bi-directional sex changer, at least in experimental conditions. The influence of body size in duration and direction of sex reversal was tested, and the changes of sexual dimorphic traits (elongated anterior dorsal spine, genital papillae, body size) and sex-cell allocation in the gonad during sex change were described. Unisex pairs of individuals, male-male and female-female of similar and different body size, were housed in aquaria recording the changes until spawning. Sex change duration showed no significant differences between protogyny (11 days) and protandry (12 days), regardless of their size. Among pairs of males of different size, the smaller individual changes sex to female whilst among pairs of females of different size larger individuals change sex to male. Among pairs of males of similar size, dominant individuals remained as male whilst subordinate individual did change sex to female. If the pair of similar size were females, the dominant individual changed sex to male whilst the subordinate remained as female. The gonads, before, throughout, and after sex change, showed that females and males contained both ovarian and testicular tissues in different ratios. The length/width ratio of the genital papilla probed to be useful to predict functional sex of individuals. The results support the idea that extreme sexual plasticity is a widespread reproductive trait in the genus Lythrypnus.

Background Homeopathy has been widely applied in freshwater species but rarely in marine fish. Farm stress destabilises host–pathogen equilibrium, favouring parasites and disease. Coccidian endoparasites cause intestinal infections and cell degeneration. Materials and Methods Naturally parasite-infested juvenile snapper Lutjanus guttatus (n = 430; weight 1.9 ± 0.01 g; length 4.9 ± 0.03 cm) specimens were distributed in group sizes of 43, in 10 fiberglass tanks (100 L) with aeration and continuous water change. Five groups in duplicate were assessed: Passival (PaV); Passival and Phosphoricum acid Similia (PaV–PhA); Passival and Silicea terra Similia (PaV–SiT); Endecto and Infecçoes (End–Inf) and a control (Ethanol) for 45 days. Feed was sprinkled with treatment (5% v/w) and dried to avoid ethanol side-effects. Statistical results were expressed as mean ± standard error of the mean. Results Intestinal coccidia were recorded histopathologically, with the least incidence attained at T45 with End–Inf treatment (p Conclusion Homeopathic treatments had a positive effect on fish health. Besides the accumulation of metabolic reserves in the liver, homeopathic treatment was associated with mucin increase in gills as well as raised production of lymphocytes and neutrophils in blood, which could act as macrophages against intestinal coccidia.

The reproductive strategy of Dosinia ponderosa at a site of the eastern coast of the Gulf of California, Puerto Libertad, Sonora is reported. Samples of visceral mass were taken from 30 clams that were collected monthly from March 2015 to March 2016, and the length and weight of the tissue without shell of each organism were recorded. Through histological analysis, the gonadal index were calculated, and the reproductive stages of the ponderous dosinia were determined. Six oocyte substages and five gonadal development stages for females and five for males are described. The sex ratio was 1:1, and no undifferentiated specimens were found. The sexual maturity phase was observed throughout the year, with two reproductive peaks in June–July and October–November. No correlation was observed between the reproductive activity and temperature or primary productivity.

The Seriola genus includes species of worldwide commercial importance due to its rapid growth and easy adaptability to confinement conditions. However, like other fish species, large mortalities occur during their early life stages, where the main problems are caused by opportunistic bacteria. Disease control strategies are thus urgently needed. The present study aimed to evaluate the efficacy of phage vB_Pd_PDCC-1 during the early development of longfin yellowtail (Seriola rivoliana), as well as its effect on microbial communities. This broad-host-range phage was added to the culture every 3 days starting from the egg-stage until 12 days after hatching (DAH) at a concentration of 1.41×1010 plaque-forming units (PFU) per mL and at a multiplicity of infection (MOI) of 1. The results showed positive effects (p 0.05) in the composition and structure of the associated microbiota. However, sequences affiliated to the Gammaproteobacteria class were displaced by those belonging to the Alphaproteobacteria class over time regardless of the treatment received. At the family level, there was a decrease in Rhodobacteraceae, Pseudoalteromonadaceae, and Flavobacteriaceae in both groups over time. To our best knowledge, this study represents the first attempt to evaluate the effect of a phage as a biological control agent during ontogenetic development of longfin yellowtail larvae. • Phages can be used against proliferation of Vibrio in fish cultures. • Seriola includes several important commercial fish species due to its rapid growth. • Phages do not cause significant changes in the associated microbiota.

Turnera diffusa (damiana) grows wild in Baja California Sur (BCS), Mexico. It is traditionally used for its aphrodisiac effects and for diabetes treatment. Two varieties (var.) have been identified: diffusa and aphro-disiaca. To evaluate the effects of water-ethanol extracts from both varieties, measurements on blood glucose, body weight, biochemical parameters, and cell blood counts were performed in a diabetic rat model. Oxidative stress was also evaluated when var. diffusa was administered. No significant reductions in blood glucose levels, in biochemical parameters, or in cell blood counts with any variety of damiana were observed; however, it helped diabetic animals to keep their body weight. Damiana var. diffusa did not mo-dify the mitochondrial nitric oxide levels and superoxide dismutase activity; however, thiobarbituric acid reactive species diminished. In conclusion, damiana can be utilized reliably in the management of diabetes because of its antioxidant potential; it promoted body weight loss in healthy animals and helped to preserve it in diabetes

Qualitative and quantitative histological and histochemical techniques were used to study seasonal dynamics of energy reserves associated with gonad development and oocyte quality in the horsemussel Modiolus capax in Bahia de La Paz during the period February 2013 to January 2014. Thirty adult mussels were collected on a monthly basis and evaluated for gonad developmental stages and changes in oocyte features (theoretical diameter, nucleus/cytoplasm ratio, lipid index, and carbohydrate index). The overall somatic coverage area versus gonad coverage area and energy reserves in the gonad (carbohydrates and neutral lipids) was also analyzed. In summer (26.5 ± 1.4°C and 2.3 ± 0.7 mg m-3 chlorophyll a), oocytes achieved greater sizes that were significantly correlated with higher lipid reserves in the gonad. This suggests that female gonads have superior breeding capacity in summer, compared with those in the autumn and winter periods, when oocyte performance and ovarian energy reserves were minimal. The evidence indicates that M. capax follows a conservative strategy to sustain gametogenesis relying on energy reserves previously stored in somatic tissue between autumn and winter. By contrast, optimal reproductive performance between April and August associates more with decreasing somatic coverage area and increasing gonad coverage area; this reflects a period of energy (lipids) transfer from storage tissues to the gonad to fuel gametogenesis. These results help establish the biological basis for gonad conditioning and maturation of M. capax to ensure continuous production of spat at the laboratory.

Eosinophilic Rickettsia-like organisms (E-RLO) were found for the first time in sick oysters of the species Crassostrea gigas, grown in Laguna de San Ignacio, Baja California Sur, Mexico, in August 2014. This work presents the histological description of development of bacteria in parasitophorous vacuoles of infected cells. Confirmative diagnosis was performed by polymerase chain reaction and in situ hybridization. Bacterial growth started with eosinophilic granules (colonial), followed by the formation and growth of intracytoplasmic inclusions. The presence of E-RLO was detected in the gill epithelium, mantle, labial palps, digestive tract, and both male and female gametes. This work describes for the first time an E-RLO in C. gigas with potential vertical transmission.

Relaxation as a sedative therapy before nucleus seeding is assumed to be stressful to some marine animals during its initial phase, before acting at the cellular level. The antioxidant activity and possible oxidative damage to soft tissues was evaluated in the winged pearl oyster Pteria sterna exposed to four relaxants, at two concentrations each. The relaxants were: propylene phenoxetol (1.5 and 2.5 mL L−1), benzocaine (0.15 and 0.25 g L−1), magnesium chloride (15 and 30 g L−1), and eugenol (0.25 and 0.5 mL L−1). The enzymatic activity (superoxide dismutase, catalase, glutathione peroxidase) and oxidative damage (TBARS, lipofuscins) were measured at 30, 60, and 120 min after immersion in each relaxant, and at 65 h representing the recovery period (filtered seawater with no relaxant). Propylene phenoxetol (2.5 mL L−1) and benzocaine (0.25 g L−1) induced >80% relaxation within the first 45 min. Variations in the activity of superoxide dismutase activity were not significant between treatments in mantle and gills, but increased in muscle at 65 h in oysters exposed to 1.5 mL L−1 propylene phenoxetol and 15 and 30 g L−1 magnesium chloride. Control oysters significantly increased catalase activity in adductor muscle and gills (30–60 min), but the activity of glutathione peroxidase did not significant vary in muscle and mantle, and only decreased in gills at 65 h exposure to 2.5 mL L−1 propylene phenoxetol. Higher TBARS concentrations, as indicative of oxidative damage, only occurred at 30 min in muscle and gills in oysters exposed to 30 g L−1 magnesium chloride and 0.25 g L−1 benzocaine. Relaxing with benzocaine caused a significant accumulation of lipofuscins in gills at 120 min, again as possible indicator of oxidative stress; lowest lipofuscins values occurred with 1.5 mL L−1 propylene phenoxetol. These results confirm that propylene phenoxetol causes minimal interaction with antioxidant enzymes and provoke little oxidative damage to soft tissues in P. sterna.

Susceptibility and immune response of Argopecten ventricosus challenged with Vibrio parahaemolyticus were determined. Mortality and median lethal concentration of V. parahaemolyticus were assessed in scallop seeds and adults challenged by immersion. Histopathological analysis was done in adults challenged by immersion. The immune response was analyzed in adults by injecting heat-inactivated bacteria in the adductor muscle. Hemolymph samples were taken at 0, 8, 24, 48, and 72 h. Time zero corresponded to samples of scallop hemolymph before challenging with vibrio. In bioassays, scallops were fed with microalgae concentrate Shellfish Diet 1800®. Seeds and adults of A. ventricosus were susceptible to V. parahaemolyticus showing a LC50 of 623 CFU mL− 1 and 62,853 CFU mL− 1, respectively. V. parahaemolyticus toxins caused lesions in digestive glands of adults analyzed. Significant variations were observed in hemocyte number, phenoloxidase activity, and lysosomal hydrolytic enzymes, mainly at 8 and 24 h, post infection. Results confirm that seeds and adults of A. ventricosus are susceptible to V. parahaemolyticus infection, but seeds are more susceptible than adults. In adults, the immune response of A. ventricosus was modulated by V. parahaemolyticus.

This study reports the basic nutritional requirement of subtropical Modiolus capax broodstock conditioned under nine diet—temperature treatments. The value of carbohydrate-rich diets was not only assessed to ensure maturation outside of the main breeding season but also to understand the interaction between diet—temperature over conditioning periods larger than the 30 days usually recommended for tropical bivalves. The experimental design included a natural diet prepared with a blend of the microalgae Tisochrysis lutea and Chaetoceros calcitrans (Micro100) and two carbohydrate-enriched diets composed of Micro100 wheat flour (MicroW) at 7% total dry weight of body tissues and Micro100 cornstarch (MicroC) at 7% total dry weight of body tissues. Maximum gonad development occurred in mussels fed MicroC at higher temperatures (26°C) where the highest frequency of partial spawning accompanied the highest lipid content in gonad and lower carbohydrate content in somatic tissues. This result reflects an early maturation compared with brood stock fed the natural Micro100 diet at 24°C. Lower temperatures (22°C) delayed maturation in all treatments and favored accumulation of carbohydrate reserves in somatic tissues with the MicroC diet. Natural diets supplemented with carbohydrate-rich sources by cereal flours are reliable alternatives to fuel and sustain gametogenesis in M. capax broodstock at high temperatures and to increase carbohydrate reserves in somatic tissues at low temperatures.

Microalgae diets supplemented with cornstarch at a rate of 0.15% of live weight to the conditioning of broodstock and spat growth of Pacific calico scallop Argopecten ventricosus were tested. To determine reproductive condition at the beginning and end of the experiment, the gonads of adults were analyzed by stereological methods. For juveniles, the weekly percent increase of spat was estimated from spat biomass volume. The microalgae diet of Tisochrysis lutea and Chaetoceros calcitrans , supplemented with cornstarch, substantially improved the reproductive status of the scallop, particularly by increasing the number of individuals in mature and mature-spawning stages with more mature oocytes by the scallop. Spat growth improved >80% in the nursery with the diet supplemented with cornstarch compared with the microalgae diet ( T. lutea , C. gracilis , and C. calcitrans ). It can be suggested that a small addition of cornstarch to a microalgae diets, boosts growth during nursery procedures and performance of A. ventricosus during the routine conditioning of the broodstock.

The effect of Streptomyces strains RL8 and N7 on the growth, survival and histological structure of the hepatopancreas of Litopenaeus vannamei was determined. Shrimp post-larvae of 0.02 ± 0.01 g were fed with diets supplemented with Streptomyces spp. RL8 and N7 at 108 CFU g⁻1 of feed for 30 days, followed by challenge with Vibrio parahaemolyticus. Toxicity was also assessed by recording the mortality associated with the use of 1-100 g/L of cell mass and 108-1010 CFU/g of feed of these strains in Artemia salina and L. vannamei, respectively. The group treated with Streptomyces sp. RL8 had significantly better weight gain (0.62 ± 0.18 g) and survival rates (84.44 ± 5.7%) after challenge, whereas the one fed with Streptomyces sp. N7 showed significantly higher survival rate (57.77 ± 6.8%) than the control group (0.55 ± 0.20 g and 11.11 ± 9.0%, respectively). The hepatopancreas of Streptomyces-fed shrimps showed better histological integrity with significantly lower degree of atrophy and necrotic tubules than their unfed counterpart. No toxicity associated with these strains was found. Consequently, they can be excellent probiotic candidates to improve the physiological status and prevent infectious diseases of cultured L. vannamei.

This work was undertaken to assess the effects that different environmental conditions of tropical and temperate aquaculture sites have on growth, survival, and reproduction of diploid and triploid Pacific oyster Crassostrea gigas. Diploid and triploid oysters were evaluated with the purpose of determining if the triploid condition results in any advantage on growth and survival that can be exploited for aquaculture of this species in tropical environments. The evaluations were performed by comparing three sites: two tropical sites in the Gulf of California and one temperate site in the Pacific Coast of the Baja California Peninsula, Mexico. When comparing tropical versus temperate sites, C. gigas growth and survival were less at the tropical sites regardless of ploidy. This can be attributed to environmental conditions, that is, high temperatures causing low productivity, in addition to an earlier-onset and sustained reproductive condition in the tropical sites when compared with the temperate site regardless of ploidy. Analyses of gonad maturation stages and number of oocytes among triploids indicated that a larger reproductive effort occurs at the tropical sites than at the temperate site. Regardless of the lower performance of both ploidy groups in the tropical environmental conditions, triploids grew significantly better than diploids in both tropical sites, and survival was the same for both ploidy groups. This contrasts with the marginal differences observed in growth between ploidies at the temperate site, where triploids showed lower survival than diploids. Possible causes for the lower triploid survival at this site are discussed.

This study expands on the criteria for selecting relaxants used in commercial production of pearls, based on the hypothesis that relaxation, before acting at a cellular level, is a stressor that triggers a battery of physiological responses. Four relaxants at two concentrations each were tested for survival, relaxation and recovery, incidence of spawning, condition index, glycogen index, mucopolysaccharide index, and lipofuscin index in the winged pearl oyster Pteria sterna . The relaxants are: propylene phenoxetol (1.5 and 2.5 mL L − 1 ), benzocaine (0.15 and 0.25 g L − 1 ), magnesium chloride (15 and 30 g L − 1 ), and clove oil (0.25 and 0.50 mL L − 1 ). Benzocaine (0.25 g L − 1 ) and propylene phenoxetol (2.5 mL L − 1 ) promoted > 85% relaxation in 50% with benzocaine, suggesting mobilization of energy reserves likely tied to spawning. In the digestive gland, the glycogen index also decreased by 30% with clove oil (0.5 mL L − 1 ), but the response with this relaxant is attributed to oxidative stress and use of glycogen reserves to cover other physiological needs, such as immune protection. Relaxing with benzocaine caused a significant accumulation of lipofuscins in the gills and mantle, again as possible indicator of oxidative stress. Based on these results, we recommend using propylene phenoxetol at 1.5 mL L − 1 for maximum relaxation with minimum deleterious effects in P . sterna .

Although Lithodes santolla is a resource with high commercial importance that has aroused interest in controlled reproduction in captivity, currently, little knowledge is available about basic reproductive aspects of this species. This research study describes detailed oogenesis stages at the histological level in adult females of the southern king crab of the Magellan and Chilean Antarctic Region. Oogenesis was quantitatively analyzed from the proliferation of 10–24 μm oogonia and during oocyte growth. Five stages of ovary development were identified: multiplication (0), previtellogenesis (I), vitellogenesis (II), maturity (III) and spawning (IV). Furthermore, 11 oocyte substages were distinguished: oogonia, chromatin nucleolus, early perinucleolus, late perinucleolus, oil globule, early vitellin globule, late vitellin globule, postvitelogenic, germinal vesicle migration and germinal vesicle breakdown. Primary vitellogenesis occurred in oocytes 180–185 μm, containing acidophilic globules and surrounded by a layer of thick follicle cells (20-40 μm). Secondary vitellogenesis was evident in oocytes at 315-321 μm with numerous acidophilic granules in the cytoplasm and surrounded by thin follicle cells; then, cortical crypts appeared, indicating the prematuration stage and preparation for ovulation. This study allows establishing gonadic changes that occur during a reproductive cycle of female L. santolla and help to strengthen aquaculture initiatives and management in the Magellan and Chilean Antarctic Region.

Mangrove oysters ( Crassostrea rhizophorae ) were collected and raised for seven months at four sites (Punta Pargo, Jorobado, Canete, and Enfermeria) around Bahia Sagua La Grande on the north coast of Cuba, to determine which site offered the best conditions for cultivation of this commercially important species. Monthly measurements of oyster height were taken on 30 oysters randomly collected from each study site. Only oysters raised at Punta Pargo and Enfermeria reached the mean commercial size (>40 mm) within the study period; these oysters were significantly larger than oysters raised at Canete and Jorobado. No significant differences in survival between the sites were observed. Punta Pargo and Enfermeria showed the best potential for oyster farming in the Bahia de Sagua area. Despite human impact on runoff caused by damming of the adjacent river, water quality remains acceptable for oyster cultivation. With proper stock management and production of selected fast-growing oysters in hatcheries, oyster farming can become an important aquaculture industry in Cuba.

This study aimed to evaluate the effect of rice bran fermented with a consortium of Bacillus and Lysinibacillus strains (RB + BLb) on the bacterial community structure and composition in the gastrointestinal tract of Pacific white shrimp (Penaeus vannamei), as well as its effect on growth performance and health status. Rice bran fermented with a commercial probiotic (RB + Com) was also evaluated for comparative purposes. Rice bran with or without probiotics, pre-fermented for 24 h, was directly added to the rearing water of juvenile shrimp for 4 weeks. At the end of the experimental period, shrimp treated with RB + BLb had a slightly better shrimp growth performance and survival than the control group; however, the differences were not statistically significant (p > 0.05) among treatments. Moreover, histological analyses showed that shrimp treated with RB + BLb improved the nutritional status compared to other treatments, by inducing an increase in lipid reserves of hepatopancreas epithelial cells. The analysis of the bacterial community composition revealed that the most prevalent families were Rhodobacteraceae, Vibrionaceae and Flavobacteriaceae. Although sequences affiliated to the Rhodobacteraceae family were more abundant in shrimp treated RB + Com, a lower proportion of sequences affiliated to the Vibrionaceae family was found in shrimp treated with unfermented rice bran (RB) or RB + Com, when compared with the control group or those treated with RB + BLb. The abundance of sequences affiliated to the Flavobacteriaceae family was significantly lower in shrimp treated with RB + BLb or RB + Com than the control group or those treated with RB. These results could explain, in part, the mechanisms of action whereby the use of rice bran fermented with a consortium of probiotic bacteria confer beneficial effects on shrimp culture.

Histological, histochemical, and biochemical changes were assessed in the Cortez geoduck Panopea globosa, during larval development to identify the main energy storage sites and biochemical patterns. Histological sections were stained with polychromic dye, whereas histochemical sections were stained for triglycerides and phospholipids (Sudan black) and for carbohydrates (Alcian blue). Spectrophotometric quantitation of proteins, lipids, and carbohydrates was carried out in 5–35 mg dry weight (DW) samples. Larvae of Panopea globosa showed the typical linear shell growth rate (21 µm d–1) and allometric, power-type relationships between shell length and DW (exponent b = 2.73) or ash-free DW (b = 2.78). Early straight-hinged larvae exhibited a rudimentary digestive system. The crystalline style, intestine, and digestive gland were conspicuous when larvae reached the early umbonate stage, whereas the gills, foot, byssal gland, and adductor muscles were first observed in late umboned larvae. Triglycerides and carbohydrates were mainly stored as droplets in the digestive gland, and their size increased with increasing larval age. Acid mucopolysaccharides were also secreted by the byssal gland. Carbohydrate content was substantially higher than triglycerides in pediveliger larvae. These finding suggests that P. globosa larvae mainly rely on a carbohydrate-based metabolism, both as a biochemical component of the larval–postlarval byssus and as an endogenous energy source during metamorphosis.

Male broodstock (Litopenaeus vannamei, 36 ± 7 g, n = 600) reproductive performance, spermatophores and reproductive tract melanization, prostaglandin concentrations and biochemical composition were evaluated after including 3.8% Ulva clathrata meal in the diet (dry base) of a commercial hatchery during 45 days. Males fed Ulva had less melanized spermatophores (120 compared with 233, P < 0.01), less bacteria in the ductus deferens (P < 0.01), more sperm cells in testicles (P < 0.05), and increased courtship activity (839 compared with 689, P < 0.01), with no effect on mortality. Ulva-fed males had more arachidonic acid (20:4n-6) in the spermatophores (P < 0.05) but this did not affect the prostaglandin concentrations in response to diet. Males fed Ulva had more carotenoids in the hepatopancreas (0.08 ± 0.02 compared with 0.01 ± 0.01 mg/g, P < 0.05), and phenolic compounds in hepatopancreas (6.1 ± 0.7 compared with 1.8 ± 0.7 mg eq. phloroglucinol/g, P < 0.05) and muscle (0.4 ± 0.3 compared with 0.2 ± 0.1 mg eq. phloroglucinol/g, P < 0.05). Males fed the Ulva also had a lesser carbohydrate content in the hepatopancreas (P < 0.01) and muscle (P < 0.01). In conclusion, supplementing fresh maturation diets with a small dose of dried Ulva allowed for improvement of reproductive performance and to decrease melanization in spermatophores and the male reproductive tract.

Acute hepatopancreatic necrosis disease (AHPND), caused by marine bacteria Vibrio Parahaemolyticus, is a huge problem in shrimp farms. The V. parahaemolyticus infecting material is contained in a plasmid which encodes for the lethal toxins PirABVp, whose primary target tissue is the hepatopancreas, causing sloughing of epithelial cells, necrosis, and massive hemocyte infiltration. To get a better understanding of the hepatopancreas response during AHPND, juvenile shrimp Litopenaeus vannamei were infected by immersion with V. parahaemolyticus. We performed transcriptomic mRNA sequencing of infected shrimp hepatopancreas, at 24 hours post-infection, to identify novel differentially expressed genes a total of 174,098 transcripts were examined of which 915 transcripts were found differentially expressed after comparative transcriptomic analysis: 442 up-regulated and 473 down-regulated transcripts. Gene Ontology term enrichment analysis for up-regulated transcripts includes metabolic process, regulation of programmed cell death, carbohydrate metabolic process, and biological adhesion, whereas for down-regulated transcripts include, microtubule-based process, cell activation, and chitin metabolic process. The analysis of protein- protein network between up and down-regulated genes indicates that the first gene interactions are connected to oxidation-processes and sarcomere organization. Additionally, protein-protein networks analysis identified 20-top highly connected hub nodes. Based on their immunological or metabolic function, ten candidate transcripts were selected to measure their mRNA relative expression levels in AHPND infected shrimp hepatopancreas by RT-qPCR. Our results indicate a close connection between the immune and metabolism systems during AHPND infection. Our RNA-Seq and RT-qPCR data provide the possible immunological and physiological scenario as well as the molecular pathways that take place in the shrimp hepatopancreas in response to an infectious disease.

The jumbo squid Dosidicus gigas has been considered to be semelparous by several authors. However, to date no studies to support this assumption have been conducted. The present work tests the hypothesis that female jumbo squid do not die after a single reproductive event and provides evidence of the presence of postovulatory follicles (Pof) in females of different sizes. They indicates previous spawning in females in which they are present. Histological analysis was performed on reproductive structures of 73 female jumbo squid from the northwest of Mexico using hematoxylin-eosin staining. Using image analysis five ovarian stages were identified: (I) previtellogenesis, (II) vitellogenesis, (III) postvitellogenesis, (IV) spawning (in which 3.73% show atresia and the presence of Pof) and (V) Postspawning, in which a higher proportion (4.86%) show atresia and Pof. It is already known that the jumbo squid has asynchronic ovarian development with partial spawning during the reproductive period. However, the consistent presence of postovulatory follicles and the presence of oocytes of different sizes and development support the hypothesis that the jumbo squid is a multiple spawner with more than one reproductive event during its life cycle.

The jumbo squid (Dosidicus gigas) has been considered a species with a semelparous life history, and this assumption has been erroneously adopted without histological evidence. Recent studies suggest that this species can spawn more than once during its life span. To identify the reproductive strategy of jumbo squid, qualitative and quantitative analyses were used in this study. Biological data were collected fortnightly from March 2008 to November 2009 off the coast of Santa Rosalia, Baja California Sur, Mexico. The histological analyses showed five stages of development: previtellogenesis, vitellogenesis, postvitellogenesis, spawning, and postspawning, with the simultaneous presence of oocytes at different substages. These results were confirmed by the presence of multiple cohorts of oocytes at each ovarian stage. Analysis applied to resting females of D. gigas confirmed that the postovulatory follicles were simultaneously found with previtellogenic oocytes denoting the ovarian recovery. The presence of postovulatory follicles at all ovarian stages and in individuals throughout the mantle length (ML) structure (from 32 to 82 cm) was an indicator of multiple spawning events. During 2008 and 2009, four ML groups (41.2, 48.5, 55.2, and 68.5 cm) and threeMLgroups (39.9, 47.8, and 53.9 cm) were observed, respectively. In conclusion, the evidence of postovulatory follicles in resting females of D. gigas indicates that the reproductive strategy of jumbo squid is iteroparity.

Hemocytes play an important role in internal defense in mollusk bivalves; they are generally divided into granular and hyaline types, where the granules possess molecules to combat foreign particles. We investigated the morphology, staining reactions, and immune-related activities of hemocytes from the pectinid lions-paw scallop Nodipecten subnodosus . We showed that, in contrast to the conditions in most bivalves and similar to other pectinids, no granular cells were observed; only very few semi-granular cells were present and the large majority of cells were hyalinocytes and blast-like cells. The cytoplasm in many hyalinocytes showed vesicles of various sizes, but none with the staining characteristics of typical granules. When hemolymph was removed from these scallops, the plasma did not clot and the hemocytes rapidly adhered to one another in suspension. When living hemocytes were placed on a glass surface, they clustered into groups of various sizes; within minutes, pseudopods extended from the cells and outward migration began. Many cells spread to form extensive networks of flat cells, and other undifferentiated cells did not spread and kept a rounded morphology. Some hemocytes were immunologically active because they phagocytize Escherichia coli bacteria. Hemocytes expressed the carbohydrates residues N-acetyl- d -glucosamine, α- d -glucose, α- d -mannose, and α-L-fucose moieties, and cytochemical assays showed activity of acid phosphatase, specific esterase, and non-specific esterase, enzymes commonly associated with lysosomes and immunologic activity. These observations serve as a useful tool for further investigation of morphofunctional studies and physiological status of scallops.

Quantitative histology was used to analyse the seasonal reproductive characteristics of the Istiophorus platypterus sailfish obtained from bycatch and recreational catches in the southeast Mexican Pacific. The analysis revealed five stages of ovarian development, eight kinds of oocytes, and one postovulation structure. The species shows an asynchronous ovary development and indeterminate fecundity. Gonadosomatic indices (GSI) indicated that sailfish have a reproductive period with peaks in September and October (mean monthly GSI=1.9 and 1.8). Females were more abundant during the second quarter, whereas males were more abundant in the third and fourth quarters. We found that the estimates of the frequency distribution of whole oocytes showed that this analysis may be useful as a tool to assess maturity. The estimated size at sexual maturity for this species in the Gulf of Tehuantepec was 150.2 cm eye–fork length.

WOS:000406370200003; Quantitative scales to evaluate maturity of female gonads were compared for a temperate oyster, Crassostrea gigas and a tropical oyster, Crassostrea corteziensis grown in the same locality. C. gigas had well-defined maturation and spawning periods and a resting phase in winter; in C. corteziensis mature individuals occurred most of the year and there were several spawning peaks. Of the quantitative scales used here, average oocyte diameter and gonad coverage area, much used for C. gigas, and ovary maturity index, less used, were inadequate to distinguish the reproductive pattern of C. corteziensis, since they both skewed the degree of maturation in vitellogenic stages in favor of C. gigas. Maximum oocyte diameter and maximum cytoplasm area were different among species at vitellogenic stages and also in previtellogenic stages. Nucleus: cytoplasm ratio was significantly different in previtellogenic and spawned stages between C. gigas and C. corteziensis. The Index of gonadal development was skewed in favor of C. gigas in postvitellogenic stage. The only scale that was comparable between species was reproductive potential, but it also was one of the most laborious. Other ordinal scales commonly used, such as a visual external evaluation of the gonad, only classified correctly a quarter of the stages.

The reproductive biology of the Panama brief squid was evaluated using reproductive indicators, and histological and histochemical analyses. A total of 2,460 squid were analyzed, which were captured during 15 exploratory fishing surveys in the Gulf of California during 2003 to 2006 and 2008. Of the total sample, 61% were female, 15% were male, and the rest were undifferentiated. Based on the frequency of the gonad developmental stages, the largest number of mature females was identified in February and October, whereas mature males were found in April and August. This result coincided with the gonadosomatic index. According to the histological analyses, we characterized 4 stages of oogenesis: previtellogenesis, vitellogenesis, postvitellogenesis with mature oocytes, and postspawning. We also characterized 6 substages of oocyte and 2 structural indicators of spawning: oogonia (Po0), previtellogenic oocyte primary (Pol), previtellogenic oocyte secondary (Po2), vitellogenic primary oocyte (Vol), sec...

Embryogenesis (single cell to twitching stage) and early larval stages (nauplius to calyptopis 3) internal morphology of the sac-spawning species Nyctiphanes simplex was investigated to explore its temporal association with gonad development and molt development cycles. Krill were collected and incubated shipboard in July 2007 and March 2010 in the Gulf of California. Cleavage patterns were similar to what is observed in broadcast-spawning species, suggesting a close phylogenetic consistency between krill species with distinct spawning strategies. Nyctiphanes simplex, like broadcast-spawning krill species, had eight Kranzzellen (K1–K8) cells during the blastula stage. The gonad of ovigerous females with embryos in the cell division stage is in the multiplication stage (Stage I). From the nauplius stage, most females are in previtellogenesis (Stage II). Only females with metanauplii occasionally have gonads in vitellogenesis (Stage III). Gonad maturity (Stage IV) occurs only after the release of the embryos from the ovigerous sac. Females with an ovigerous sac were invariably at the intermolt stage, suggesting a precise synchronization among processes of molting, gonad development and embryo release to produce consecutive broods. Lipid and carbohydrate storage decreased exponentially throughout embryonic and early larval development, depending on their endogenous reserves. When metanauplii leave the ovigerous sac, they have low storage lipid (,2%) and carbohydrate (,5%). These proportions suggest a theoretically short period-of-no-return (,2 days), when they transform into the first feeding stage (calyptopis 1).

This study presents complimentary data of early growth and age/size of first reproduction of hatchery-reared Crassostrea corteziensis juveniles cultivated in the field for 9 months. Samples of oysters and gonads were collected monthly to determine absolute growth and growth rates, as well as overall gonad development. At the end, adult oysters ranging 75.6 ± 0.62 mm shell height (SH) yielded a mean growth rate of 0.308 mm day−1, which is among the highest reported for the species. Gametogenesis began in March–April and spawning occurred during August and September. Males outnumbered females at smaller sizes, but female were more abundant at larger sizes. From planting time in the field, the age/size of first maturity was 3.25 months for males (42 mm SH) and 4.5 months for females (54 mm SH), with a mean population age of 4.75 months for males (size range 55–59 mm) and 5.25 months for females (60–64 mm). Based on these results, and the time needed for hatchery care prior planting juveniles in the field (2.25 months), we propose limiting fishing of wild oysters to sizes >65 mm height to allow them to breed at least once and contribute to restoring wild populations.

Tools of histochemistry and digital image analysis were used to quantify changes in the coverage area of lipid droplets (lipid content) of oocytes of the penshell Atrina maura during oogenesis and to determine its relation to changes in water temperature and seston content. These data led to calculating a lipid index as a criterion of gamete development and quality. Gonads were collected monthly for 18 mo and prepared for histochcmical processing with Sudan Black B for identification of lipids. Finished slides were digitized for determining stages of oogenesis and variations in the size of oocytes. Two periods of greatest reproductive activity occurred during the study, with a lower peak from November through January (∼15°C; 26 mg/g) and a major peak from April through June (∼20°C; 25–40 mg/g). Oocyte area significantly varied during the stages of active development (516–2,743 µm2), ripeness (1,073–2,930 µm2), spawning (145–2,939 µm2), and atresia (331–2,001 µm2). Lipid incorporation into oocyte ...