Squid Diet Research Articles

Effects of dietary squid oil on breeding performance and embryonic and larval development of butter catfish Ompok pabda

The present study was conducted to determine the effects of squid oil on the endangered butter catfish, Ompok pabda to confer enhanced breeding with embryonic and larval development for promoting its aquaculture. A total of 360 fish were obtained from the Brahmaputra River, Mymensingh, Bangladesh, of which, 60 fish stocked in each tank having an initial weight and length of 16.35 ± 0.57 g and 15.25 ± 0.38 cm, respectively, in the cisterns of 1.22 × 2.44 × 1.25 m (total 6 cisterns) maintained at 90 cm water depth. During the experimental period, a constant physico-chemical conditions of water such as temperature, pH, and dissolved oxygen (DO) were 26.5 ± 2 °C, 7.4 ± 0.2, and 6.7 ± 0.5 ppm, respectively, were maintained in each cistern. As the source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), dietary 1 % squid oil (SQO) was supplemented in the diet of the treated group (SQO diet) to compare while the control group offered with basal diet without SQO supplementation (CON diet). The fecundity, spawning, fertilization, hatching rate, and survival rate of fry in SQO group were significantly (P < 0.01) higher than in the CON group. Moreover, better early embryonic and larval development of fish was observed in the SQO group i.e. size of fertilized egg diameter, growth and early developmental stages of larvae but not significantly different from the control group. Collectively, the results of the present study showed that dietary SQO supplementation improved the breeding and reproductive performances of butter catfish. The findings of this study could assist to develop a nutrient-rich diet for the better broodstock development of butter catfish at the farm level which may ultimately reduce the mortality and poor survival of offspring of this commercially important catfish species.

Gonad Quality of Banana Shrimp Male Broodstock Penaeus merguiensis (De Man, 1888) Fed Different Natural Diets.

A study was carried out to determine the maturation period, quality and quantity of sperms production in Banana shrimp male broodstock, Penaeus merguiensis fed different natural diets. The three different natural diets namely; squid, fish and shrimp flesh used in this study were obtained from known sources and fed to the tested shrimp in triplicate groups. Based on the results obtained, squid seem to be the most effective natural diet as it enhances the sperms maturation within 20 days. Feeding fish and shrimp flesh as diets for the Banana shrimp broodstock resulted in the observation of maturation in 22 and 24 days, respectively. Similarly, squid diet also recorded the highest (p = 0.002; p < 0.05) sperms count (58.6 to 74.5) as compared to fish diet (44.0 to 61.3) or shrimp diet (28.0 to 42.8). Also, feeding squid diet resulted in a higher percentage of live sperms with ranged between 97.75% to 98.80%. On the other hand, broodstocks fed fish and squid flesh was observed with ranges of between 96% to 97.86% and 92.54% to 96.06%, respectively. It was therefore concluded that squid diet was most effective to improve sperm quality, quantity and maturation period in male broodstock of P. merguiensis. Further study should be carried on the reproductive performance of broodstock fed with squid as diets and it effect on the performances of post larvae obtained.

Growth Enhancing Effects of Squid By-Product Hydrolysate in Plant Protein-Based Diet Fed to Black Tiger Shrimp, Penaeus monodon Fabricius, 1798

The present study evaluated the potential of squid by-product hydrolysate as fishmeal replacement in the plant-based diet of juvenile black tiger shrimp, Penaeus monodon Fabricius, 1798. Five experimental plant protein-based diets were formulated containing squid by-product hydrolysate to replace fishmeal at 0, 25, 50, 75 and 100 %. These experimental diets were fed to triplicate groups of P. monodon for 8 weeks. Results revealed that 25 % fishmeal replacement with squid by-product hydrolysate resulted in growth enhancement, attributable to increased feed intake and gut lactic acid bacteria proliferation. The shrimp fed with 100 % replacement level exhibited a similar growth response with the control group. Protein retention was not affected by the fishmeal replacement levels, but lipid retention was found higher in all treatments with squid by-product hydrolysate than the control. Digestive protease activity decreased with increasing levels of hydrolysate while α-amylase and lipase activities were not affected. Hepatopancreas histology showed thatB-cells dominated the control group while R-cells proliferated with increasing inclusion of dietary squid by-product hydrolysate. These results collectively indicate that fishmeal could be totally replaced with squid by-product hydrolysate and 25 % fishmeal replacement could promote the growth of juvenile P. monodon.

Nutritional Performance of Juvenile Red Drum (Sciaenops ocellatus) Fed Various Fish, Shrimp, and Squid Diets

Aquaculture is the fastest-growing sector of protein production in the world. Due to the rising costs of fishmeal used as a critical ingredient to make pelleted fish feed, the industry is moving to replace fishmeal as a primary protein source without reducing the growth rate of aquacultured fish. A 12-week feeding trial utilizing juvenile red drum (Sciaenops ocellatus) was conducted to determine the performance of various combinations of natural diet components including fish (Decapterus punctatus), shrimp (Litopenaeus vannamei), and squid (Loligo opalescens and Illex), in addition to a commercial fishmeal-based pelleted feed, fed isocalorically to identify if there is an optimal combination for red drum growth and health. These results can provide information to develop fishmeal replacement diets (FMRDs) that can more closely mimic the performance of natural diets. Traditional aquaculture metrics showed that fish fed the diet comprised only of fish had the highest specific growth rate, condition factor, and protein conversion efficiency, with the lowest feed conversion ratio, indicating the fish component was the highest performing component for red drum growth on a calorically fixed ration. There were significant differences among eight groups found for traditional aquaculture metrics ( p &lt; 0.05 ). The commercial pelleted feed performed better than all but the fish only natural diet treatments in terms of growth on a fixed ration, which indicated that it is nutritionally balanced. The results of this study show that there were performance differences between juvenile red drum fed various natural diets. There has been an investigation into the metabolome of these fish to identify potential metabolites for supplementation into FMRDs, which is not addressed in this paper.

Effects of dietary squid liver powder content on the growth performance, cadmium accumulation and nonspecific immune response of juvenile olive flounder Paralichthys olivaceus

This study was conducted to investigate the effects of dietary squid liver powder (SLP) content on the growth performance, cadmium accumulation, and non-specific immune response in juvenile olive flounder. The experimental diets included the control diet (S0) without addition of SLP and 5 different treatments which contained 3.9 % (S3.9), 12.0 % (S12.0), 20.1 % (S20.1), 36.2 % (S36.2), and 52.3 % (S52.3) dietary SLP with the final cadmium concentrations of 0.4, 0.8, 1.7, 2.5, 4.6, and 6.4 mg kg−1 diet, respectively. For feeding trial, seven hundred twenty fish (initial weight of 55 g) were randomly distributed into six dietary groups in triplicates (40 fish per tank). At Week 1, 2, 4, 6, and 8 (the end) of the trial, 2 fish were collected from each tank for cadmium content determination. There was no significant difference in survival between all the experimental diets. Weight gain and feed efficiency of fish significantly increased in the fish fed S52.3 compared to the other treatments. Cadmium contents in the viscera including liver significantly increased as dietary SPL content goes up at all analyses from Week 1 to 8. On the contrary, the whole body excluding viscera showed no significant difference in the cadmium content between the experimental diets, and cadmium contents in the whole body were measured below 0.08 mg kg−1 in all the experimental groups at all times of analysis during the 8 week experiment. Superoxide dismutase and lysozyme activities in the fish plasma were significantly affected by dietary SLP contents. It could be concluded that cadmium accumulation in body (excluded the viscera and liver) of juvenile olive flounder fed with SLP-containing diets up to 8 weeks does not raise an issue related to food safety.

Ecology of Moroteuthopsis longimana at the sub-Antarctic Prince Edward Islands, revealed through stable isotope analysis of squid beaks

Understanding the underlying ecological factors that affect the distribution patterns of organisms is vital for their conservation. Cephalopods such as giant warty squids Moroteuthopsis longimana are important in the diets of marine predators, including grey-headed albatrosses Thalassarche chrysostoma, yet our understanding of their habitat and trophic ecology remains limited. We investigated the habitat and trophic niche utilised by M. longimana through the δ13C and δ15N profiles captured in their beaks. M. longimana beaks were collected around grey-headed albatross nests at the Prince Edward Islands during 2004 and 2013 (n = 40 beaks). The results showed distinctly Antarctic distributions (δ13C = -24.0 ± 1.0‰, mean ± SD) for M. longimana, consistent with albatrosses foraging at the Southwest Indian Ridge, as opposed to broader foraging zones utilised by albatrosses from Îles Crozet and Îles Kerguelen. Slightly lower δ15N values (5.4 ± 0.7‰) were found compared to other islands in the Indian Sector of the Southern Ocean, which may indicate more crustaceans in the squid diets. Sequential sampling along the lateral walls of individual beaks (n = 4) revealed ontogenetic shifts in δ13C and δ15N values, but individual variation in these shifts requires further investigation.

What is on the menu? Feeding, consumption and cannibalism in exploited stocks of the jumbo squid Dosidicus gigas in south-central Chile

Only few studies on the feeding and cannibalism behavior of the jumbo squid have been conducted in the Humboldt Current System despite this species is currently considered an important economic resource. It is possible that the diet of this ommastrephid squid varies throughout the year, among areas and body size. Therefore, we herein collected jumbo squids from commercial catches during January to December 2014 using purse-seine nets. The stomach contents were analyzed in terms of frequency of occurrence, number, and weight of prey items. The diet composition was analyzed using Detrended Correspondence Analysis. The variation of jumbo squid diet composition was evaluated from different biological and temporal predictors (sex, maturity, body size and months), considering and analyzing cannibalism. Daily ration was estimated using three methods to calculate consumption and consumption/biomass ratio. Our results suggest that there are significant differences in diet throughout the year, among sizes, and between sexes, however, no differences were found according to the interactions of these factors, except for the interaction between sex and month. In addition, significant differences were detected for each factor (sex, month and body size) when evaluating cannibalism, although these differences were only significant when factors were evaluated independently. Body size was the best predictor of diet composition, richness and cannibalism variation. Stomach content weight was highly biased due to the advanced level of digestion, which in turn biased the diet based on weight, daily ration and consumption analyses. In this sense, the bioenergetic model based on water temperature fitted better than models based on stomach content weight and body mass. These results showed that D. gigas mostly predates on crustaceans and cephalopods, which contrasts with most ecosystem models that suggest that this species highly predates on commercially-exploited fish species.

Dietary squid paste supplementation promotes feed intake via brain-gut dynamic response in Chinese soft-shelled turtle Pelodiscus sinensis.

BackgroundAs the primary source of protein for aquaculture, fishmeal has reached the extremity of sustainable development, our previous studies have proven that rice protein concentrate and squid paste are outstanding protein source and stimulant for Pelodiscus sinensis. However, little attention has been given to the molecular mechanism of the appetite modulated by the dietary nutrient factor, especially for a reptile. Thus, the present study aimed to evaluate feed intake and brain-gut dynamic responses to dietary rice protein concentrate and squid paste in Chinese soft-shelled turtle Pelodiscus sinensis.MethodsThree isonitrogenous and isoenergetic practical diets were formulated including 60% fishmeal (CT), 42% fishmeal + 18% rice protein concentrate (RP) and 42% fishmeal + 18% rice protein concentrate + 1% squid paste (RPS), respectively. Microcapsule lysine was supplemented in RP and RPS diets to balance the amino acid profile. Turtles (initial weight 30.65 ± 0.97 g) were fed three times daily to apparent satiation. After the 8-week feeding trial, the turtles were exposed to 48h food deprivation, then the dynamic expression of the orexigenic and anorexigenic peptides were measured.ResultsThe results showed that no significant effect was observed on feed intake when fishmeal was replaced by rice protein concentrate (P = 0.421), while significantly improved feed intake was found by squid paste supplemented (P = 0.02). The mRNA expression of anorexigenic peptides, such as leptin receptor, insulin receptor, pro-opiomelanocortin, cocaine and amphetamine-regulated transcript, cholecystokinin (and its receptor) and glucagon-like peptide-1 receptor in the brain increased significantly at 3 h past feeding (P < 0.05), and then decreased. Nevertheless, neuropeptide Y and peptide YY mRNA expression showed the valley at 3h and peak at 12h past feeding. Intestinal cholecystokinin receptor and glucagon-like peptide-1 receptor mRNA expression showed no difference during the postprandial time (P > 0.05). The results suggested that squid paste is an outstanding stimulant for Pelodiscus sinensis. Furthermore, the orexigenic and anorexigenic peptides evaluated here might play an essential role in short-term fasting to this species, of which the dynamic expression levels were regulated by squid paste.

DETERMINE THE COMPETENCE OF DIFFERENT FRESH DIETS TO IMPROVE THE SPERMATOPHORE SUPERIORITY OF GIANT BLACK TIGER SHRIMP, PENAEUS MONODON (FABRICIUS, 1798)

The intention of the present study was to assess the effect of fresh natural food on spermatophore quality and analysis by the way of sperm weight, count, viability as well as the proximate analysis of offered food and shrimp brood stock. The experiment was carried out with the three following treatments; fresh squid, polychaete and beef liver up to 5 weeks. All parameters were measured by the starting of 3 rd week (15 days) and the end of the (35 days) of the experiment. Spermatophore quality was evaluated by spermatophore weight, sperm count, viability and proximate analysis of the treatment and shrimps. The content of three essential fatty acids, Arachidonic acid (AA), Eicosapentanoic acid (EPA) and Docosahexaenoic acid (DHA) from wild Penaeus monodon brood stock were evaluated in comparison with natural diet fed to P. monodon . Spermatophore of wild male brood stock contained higher levels of AA than those of artificial fed males. Polychaete has higher proportion of AA to EPA and DHA. At the end of the treatment the sperm viability and count, shrimp and spermatophore weight were significantly different among treatment and control (p<0.05). The present study concludes that the fresh squid diet is highly preferred over the diets influence on increasing the spermatophore quality, therefore use of fresh squid only is recommended for the maturation of male P. monodon brood stock. // //

Testis Maturation Stages of Mud Crab (Scylla olivacea) Broodstock on Different Diets

The aim of this study was to investigate how various diets influence testis maturation stages in mud crab (Scylla olivacea) broodstock. Morphological and histological assessments were performed in triplicate (10 male crabs each). Daily, subject crabs were fed a squid (Loligo sp.) and a fish (Decapterus sp.) diet at 5-10% of body weight. Diets were analyzed following methods from the Association of Analytical Communities (AOAC). In comparison to control (wild) crabs, the two diets generally did not cause significant differences (p>0.05) in body weight, carapace width and gonadosomatic index (GSI), except in the GSI of squid-fed crabs (p<0.05). At the end of the experiment, crabs that reached Stage 3 testis maturation included were 6 fish-fed individuals and 23 squid-fed individuals. Additionally, differences in crude protein and fat levels across diets influenced the nature of male gonadal development. In conclusion, a squid diet was sufficient to induce Stage 3 testis maturation in Scylla olivacea within 60 days of culture. Our results prove the usefulness in developing appropriate feeding regimes for male Scylla olivacea broodstock.

Induced Spawning and Larval Culture of Golden Trevally

AbstractThe Golden Trevally Gnathanodon speciosus is a popular sport, food, and ornamental fish native to the tropical Indo‐Pacific region, yet there is little information regarding aquaculture technologies. A group of Golden Trevally broodfish was acquired from a local public aquarium in an effort to attempt captive spawning and larval culture. Broodfish were held in 4,500‐L recirculating aquaculture systems and conditioned on a mixed diet of squid, capelin, and krill. Once water temperatures were averaging 26°C, Ovaplant was administered to mature broodfish (six males, two females) in one of the systems. Broodfish spawned on three separate occasions after this hormone administration, releasing probably 35,000 eggs/female during each spawn. Fertile eggs from two of these spawns were used for larval culture attempts. Larvae were stocked into five 104‐L tanks at densities up to 173 larvae/L. Throughout larval culture trials, larvae were fed a combination of copepod nauplii, enriched rotifers, Artemia nauplii, and a dry diet, and the tank water was inoculated with live Tahitian strain Isochrysis galbana up to 26 d posthatch (dph). Larvae achieved complete metamorphosis around 30 dph. By 45 dph, nearly 4.3% of the larvae initially stocked survived and reached about 3.7 cm in length. These successful spawning induction and larval culture trials are promising for future development of a commercial‐level production industry for Golden Trevally.

Learning to distinguish between predators and non-predators: understanding the critical role of diet cues and predator odours in generalisation.

It is critical for prey to recognise predators and distinguish predators from non-threatening species. Yet, we have little understanding of how prey develop effective predator recognition templates. Recent studies suggest that prey may actually learn key predator features which can be used to recognise novel species with similar characteristics. However, non-predators are sometimes mislabelled as predators when generalising recognition. Here, we conduct the first comprehensive investigation of how prey integrate information on predator odours and predator diet cues in generalisation, allowing them to discriminate between predators and non-predators. We taught lemon damselfish to recognise a predator fed a fish diet, and tested them for their response to the known predator and a series of novel predators (fed fish diet) and non-predators (fed squid diet) distributed across a phylogenetic gradient. Our findings show that damselfish distinguish between predators and non-predators when generalising recognition. Additional experiments revealed that generalised recognition did not result from recognition of predator odours or diet cues, but that damselfish based recognition on what they learned during the initial conditioning. Incorporating multiple sources of information enables prey to develop highly plastic and accurate recognition templates that will increase survival in patchy environments where they have little prior knowledge.

The role of sardine as prey for pelagic predators in the western Mediterranean Sea assessed using stable isotopes and fatty acids

This study combined the analysis of fatty acids and stable isotopes of nitrogen and carbon to test the hypothesis that the pelagic food web of the south Catalan Sea has a wasp-waist structure supported by sardines Sardina pilchardus. If this hypothesis were correct, most predators would be expected to have stable isotope ratios and fatty acid profiles consistent with those derived from a sardine-based diet. However, this was true only for mackerel Scomber scomber, blue butterfish Stromateus fiatola, all sea-birds and oceanic loggerhead turtles Caretta caretta. The values of the DHA/EPA index of neritic logger-head turtles and striped dolphins Stenella caeruleoalba were also consistent with a sardine/ squid diet, but their trophic positions were too high. On the other hand, the DHA/EPA index of most predatory fishes in- dicated that anchovies Engraulis encrasicolus and/or horse mackerel Trachurus trachurus were their main prey. Nevertheless, some amounts of low trophic level invertebrates were likely to be consumed by some predatory fishes, because their trophic positions where lower than expected from a fish-based diet only. The heterogeneous distribution of phytoplankton groups above and below the thermocline during the warm season is hypothesized to be the primary reason for this food web structure, although the strong reliance of some seabirds on sardines is the likely consequence of a massive consumption of discards from fishing boats. In short, there is little evidence for a wasp-waist structure based on sardine, which may explain why the populations of predators fluctuate less than the population of sardines.

Dietary squid ink polysaccharide induces goblet cells to protect small intestine from chemotherapy induced injury.

Gastrointestinal mucositis induced by chemotherapy is associated with alterations of intestinal barrier function due to the potential damage induced by anti-cancer drugs on the epithelial cells. Goblet cells, an important epithelial lining in the intestine, contribute to innate immunity by secreting mucin glycoproteins. Employing a mouse model of chemotherapy induced intestinal mucosal immunity injury by cyclophosphamide, we demonstrated for the first time that polysaccharide from the ink of Ommastrephes bartramii (OBP) enhanced Cyto18, which is a mucin expression in goblet cells. The up-regulation of mucins by OBP relied on the augmented quantity of goblet cells, but not on the changes in the ultrastructure of endoplasmic reticulum (ER). Our results may have important implications for enhanced immunopotentiation function of functional OBP on intestinal mucosal immunity against intestinal disorders involving inflammation and infection.

Ecological tracers and at-sea observations document the foraging ecology of southern long-finned pilot whales (Globicephala melas edwardii) in Kerguelen waters

The food and feeding ecology of the poorly known southern long-finned pilot whale (Globicephala melas edwardii) was investigated using ecological tracers (muscle and skin δ13C and δ15N, and total mercury, Hg) on individuals from two mass strandings together with at-sea observations of live animals in Kerguelen waters, southern Indian Ocean. Sightings of cetaceans from longliners over 9 years (2003–2012) emphasized the regular occurrence of pilot whales in slope waters surrounding the archipelago. Tissue δ13C values (a proxy of consumer foraging habitat) suggest that pilot whales fed in slope waters and in oceanic subantarctic waters over the last months preceding stranding. Tissue δ15N values and Hg concentration (dietary proxies) indicate a high trophic position (~4.7) for the pilot whales, likely corresponding to a mixed diet of fish and squid (not crustaceans) of undetermined species. Both skin and muscle Hg concentrations were positively and linearly correlated to individual size with no concomitant δ15N changes, which can be interpreted as a progressive Hg accumulation in tissues of individuals throughout life with no parallel dietary shift. Skin and muscle Hg concentrations were linearly and positively related; hence, Hg skin could be used as a proxy of Hg concentration in muscle (a main Hg reservoir of the body). Kerguelen southern long-finned pilot whales were less Hg contaminated than most pilot whale populations studied so far, thus suggesting that they are not at a high risk to Hg-induced damages in the remote islands of the Southern Ocean.

Hypolipidemic potential of squid homogenate irrespective of a relatively high content of cholesterol.

BackgroundOur previous study has shown that regardless of a relatively high amount of cholesterol, squid homogenate lowers serum and hepatic cholesterol in animals. Since this work, we have developed a new method to inhibit autolysis of squid proteins with sodium citrate. This study aims to investigate how squid homogenate prepared with sodium citrate affects lipid metabolism in Sprague–Dawley rats at the molecular level.MethodsWe prepared squid homogenate with sodium citrate to inhibit autolysis of squid protein. In Experiment 1 (Exp. 1), rats were given a cholesterol-free control diet or a squid diet, with squid homogenate added at the level of 5% as dietary protein for 4 weeks. Blood, the liver and adipose tissue were taken after 6 hours fasting. Serum and hepatic lipids and activities of enzymes related to lipid metabolism were measured. In Experiment 2 (Exp. 2), the above-mentioned diets had cholesterol added at the level of 0.1% and given to rats. Lipid parameters, enzyme activities, and gene expression of proteins involved in lipid metabolism in the liver and the small intestine were determined. In addition, feces were collected for two days at the end of Exp. 2 to measure fecal excretion of steroids.ResultsIn Exp.1, serum triglyceride and cholesterol were ~50% and ~20% lower, respectively, in the squid diet-fed rats than in the control diet-fed animals while hepatic cholesterol was ~290% higher in the squid diet-fed rats. When cholesterol was included into the diets (Exp. 2), serum lipids were significantly lower in the squid group while no difference of hepatic lipid was seen between two groups. Activities of hepatic lipogenic enzymes were significantly lower in rats on the squid diet while the enzyme responsible for fatty acid oxidation was not modified (Expt. 1 and 2). Hepatic level of mRNA of microsomal triglyceride transfer protein was significantly lower in the squid group. In the small intestine, the squid diet exhibited significantly lower gene expression of proteins involved in fatty acid transport and cholesterol absorption. Fecal secretion of acidic steroids, but not neutral steroids, was higher in rats fed the squid diet than in those fed the control diet.ConclusionThese results imply that newly-developed squid homogenate has hypolipidemic potential primarily through decreased absorption of bile acids in the small intestine and suppressed lipogenesis in the liver.

Dietary squid ink polysaccharide could enhance SIgA secretion in chemotherapeutic mice.

Secretory immunoglobulin A (SIgA) is a non-inflammatory antibody that shields internal body surfaces, such as in the intestine to neutralize pathogens in the lumen of the intestine. As chemotherapy seriously damages the mucosal immune system, we herein demonstrated that polysaccharide from the squid ink of Ommastrephes bartrami (OBP) activated intestinal SIgA secretion to prevent chemotherapeutic injury. Using a mouse model of chemotherapy induced intestinal injury by intraperitoneal injection of 50 mg kg(-1) cyclophosphamide, our results showed an enhanced SIgA concentration in intestinal mucosa by OBP administration and the higher production of SIgA relied on the greater expression of IgA, J chain and pIgR. Furthermore, the higher expressions of IL-6, IL-10 and TNF-α increased by OBP treatment contributed to enhanced IgA and J chain synthesis in IgA(+) plasma cells, and pIgR expression in epithelial cells. It also triggered a prompt immunoglobulin secretory pathway confirmed by enhanced UPR (unfolded protein response) effectors XBP-1s and Bip expression. Our results have important implications for the mucosal immunity enhancement effects of OBP as a functional food component for chemotherapeutic patients.

Dietary squid ink polysaccharides ameliorated the intestinal microflora dysfunction in mice undergoing chemotherapy.

Gastrointestinal mucositis and infection by chemotherapy treatment are associated with alteration of intestinal microflora and bacterial translocation due to the potential damage induced by anti-cancer drugs on the intestinal barrier and microbiota homeostasis. This study aimed to investigate the protective effect of dietary polysaccharides on chemotherapy induced intestinal microflora dysfunction. In the current contribution, with a mouse model intraperitoneally injected with 50 mg kg(-1) of cyclophosphamide (Cy) for 2 days, we revealed that polysaccharides from the ink of Ommastrephes bartrami (OBP) altered the intestinal microflora composition. OBP retarded the excessive growth of intestinal bacteria induced by cyclophosphamide, based on 16S rRNA gene (16S rDNA) quantification. The clone libraries of intestinal bacteria 16S rDNA were used to decipher the difference in bacterial community structures in different groups of mice. Followed by RFLP evaluation and OTU abundance analysis, they imply that OBP changed the intestinal microflora composition, in which the quantity of probiotic Bifidobacterium got up-regulated but Bacteroidetes decreased in mice undergoing chemotherapy. Our results may have important implications for OBP as a functional food component or nutrient against chemotherapy induced intestinal injury and potential pathogenic intestinal disorders involving inflammation and infection.

Use of mixing models for Humboldt squid diet analysis: Reply to Field et al. (2014)

Use of mixing models for Humboldt squid diet analysis: Reply to Field et al. (2014)

Lowering effect of firefly squid powder on triacylglycerol content and glucose-6-phosphate dehydrogenase activity in rat liver.

Effects of dietary firefly squid on serum and liver lipid levels were investigated. Male Wistar rats were fed a diet containing 5% freeze-dried firefly squid or Japanese flying squid for 2 weeks. There was no significant difference in the liver triacylglycerol level between the control and Japanese flying squid groups, but the rats fed the firefly squid diet had a significantly lower liver triacylglycerol content than those fed the control diet. No significant difference was observed in serum triacylglycerol levels between the control and firefly squid groups. The rats fed the firefly squid had a significantly lower activity of liver glucose-6-phosphate dehydrogenase compared to the rats fed the control diet. There was no significant difference in liver fatty acid synthetase activity among the three groups. Hepatic gene expression and lipogenic enzyme activity were investigated; a DNA microarray showed that the significantly enriched gene ontology category of down-regulated genes in the firefly squid group was "lipid metabolic process". The firefly squid group had lower mRNA level of glucose-6-phosphate dehydrogenase compared to the controls. These results suggest that an intake of firefly squid decreases hepatic triacylglycerol in rats, and the reduction of mRNA level and enzyme activity of glucose-6-phosphate dehydrogenase might be related to the mechanisms.