Crab Meal Research Articles

Performance of crustacean and insect meal based diets on the growth and digestive enzyme profile of pearlspot Etroplus suratensis (Bloch, 1790)

A feeding trial of 75 days was conducted in tanks to study the performance of shrimphead meal (SM), crab shell meal (CM) and silkworm pupae meal (SWP) on the growth anddigestive enzyme profile of pearlspot, Etroplus suratensis. Four iso-nitrogenous diets with31.5% crude protein replacing 50% fishmeal (FM) in the diets were formulated viz., SM (T1),CM (T2), SWP (T3) and a control (C). Pearlspot advanced fry, 2 cm in length and 1.1 g inweight, was stocked at 60 nos per tank. After 75 days of the experiment, feed conversionratio (FCR), feed efficiency ratio (FER) and protein efficiency ratio (PER) were observed to besignificantly better (p<0.05) in all treatment groups (T1, T2 and T3) than in control (C). T2 (CM)fed fishes exhibited a maximum specific growth rate (SGR) of 3.25±0.09, and significantlyhigher (p<0.05) weight gain (11.54±0.78 g) than T1, T3 and control. In enzyme assays, T2 (CM) fedfishes exhibited significantly higher (p<0.05) protease activity than other treatments.Lipase activity was significantly higher (p<0.05) in T3. However, there was no significantdifference with control diet-fed fishes. Significantly higher (p<0.05) activities of amylase,malate dehydrogenase (MDH) and lactase dehydrogenase (LDH) were observed in all thetreatments compared with control. The outcomes of the present study indicate that crabmeal (31.5% CP) could be effectively utilised as a 50% replacement for fishmeal in the dietof E. suratensis advanced fry for higher yields. Keywords:Crab meal, Enzyme activity, Growth, Shrimp meal,Silkworm pupae meal

Occurrence and distribution characteristics of aged microplastics in the surface water, sediment, and crabs of the aquaculture pond in the Yangtze River Delta of China

The artificial breeding of freshwater crabs in China has become the main source, accounting for 45.69 % of the total output in 2020. However, microplastics widely exist in ponds due to the addition of meals, and the aging and breakage of plastic tools, and people know little about the occurrence of microplastics in the environment and the tissues of crabs during the cultivation of crabs in ponds. In this study, the abundance and characteristics of microplastics in ponds and crabs were studied finely, and the types of microplastics produced by meals and tools and the aging degree of microplastics in different media were studied in a typical aquaculture experimental base in the Yangtze Estuary of China. After we digested all the samples, there were microplastics in the water, sediment, and inedible part of crabs and crab meals, mainly in fiber shape, with a particle size of 100~300μm, and they have a certain degree of aging. The abundance of microplastics in surface water ranges from 4.4 to 10.8 items/L, and that in sediment ranges from 28.6 to 54.3 items/100 g·dry weight sediments. The average abundance of microplastics in crabs was 23.9 ± 15.9 items/individual. The content of microplastics in crabs' intestinal tissue was the highest, followed by gills and hepatopancreas. At the same time, the microplastics found in crabs were positively correlated with crab body weight and negatively correlated with hepatopancreas index. The results show that in the process of artificial breeding pond feeding, microplastics will be released from the process of meals dissolving in water, and fall off due to wear and tear during the use of tools. Microplastics found in the water, sediments and the tissues of crabs were all aged. Humans have a risk of ingesting microplastics when they eat the tissues of nonedible parts of crabs.

Effect of Different Enriched Crickets (Gryllus sigilatus) on Growth and Pigmentation of Asian Arowana (Scleropages formosus) Var. Super Red

This study aimed to evaluate the effect of crickets enriched with a source of carotenoids on fish’s growth, colour, and total carotenoid content in juvenile Asian Arowana (Scleropages formosus). Six juveniles were fed with different enriched crickets (G. sigilatus) based on the following treatments: (A) Crickets fed with fish feed without enrichment, (B) Crickets fed with fish feed containing 500 ppm of synthetic astaxanthin, and (C) Crickets fed with a combination of 50% fish feed, 48% sand crab meal and 2% marigold petal meal. The results of the study revealed that The weight gain (WG), specific growth rate (SGR), feed efficiency (FE), length gain (LG), and survival rate (SR) for treatment A were 110 g, 1.16% head/day, 45.79%, 10.98 cm, and 100% respectively. There was also no significant difference (P>0.05) with the other treatments. However, treatment B had a positive effect on the redness (a*) of the Arowana tail with a value of 9.52, and treatment C increased the yellowness (b*) of the Arowana body with a value of 2.77 (P<0.05), which was different to the other treatments. There were no differences between any of the treatments concerning the effects on lightness (L*), chromaticity (C*), and hue (H*) on either the body or the tail. The astaxanthin enrichment produced the highest carotenoid content (P<0.05) with a value of 45.09 µg/g. Enriching crickets with astaxanthin influence colour and carotenoid content but not the growth of the Asian Arowana fish.

Replacement of Crab Meal for Fish Meal on Performance and Egg Quality Characteristics of Laying Hens

A 12-week experiment was conducted to evaluate the effect of crab meal replacement for fish meal on laying performance and egg quality characteristics. Two hundred laying hens at twelve weeks of laying life were used for the experiment. The laying hens were divided into five groups. Five dietary treatment were formulated to form T1, T2, T3 and T4 and crab meal was incorporated in the diet to replace fish meal at 0%, 25% 50% 75 and 100% levels respectively. Each group of laying hens was randomly assigned to one of the treatment diets in a completely randomized design. Each group was further divided into four (4) replicates of ten (10) birds each. Feed and water were supplied ad libitum. Results showed that the treatment diets did not have significant (P>0.05) influence on final weight, body weight changes, feed intake, and feed conversion ratio of the laying birds. On egg quality characteristics, there was significant difference (P<0.05) on egg shell weight, shell thickness, egg weight, and egg breaking strength of the laying hens. Laying hens fed diet containing 100%, 75% crab meal replacement for fish meal recorded significantly (P<0.05) higher values for the afore-mentioned parameters. These results showed that replacement of fish meal with crab meal can be recommended to poultry farmers that are into commercial egg and breeder production whose target is shell thickness, egg breaking strength to reduce egg loss due to low shell thickness and egg breaking strength.

Does the addition of ingredients affect mercury and cadmium bioaccessibility in seafood-based meals?

Despite the bioaccessibility of nutrients and contaminants present in individual seafood products has been thoroughly studied, information is extremely limited in what concerns complete seafood-based meals, where interactions between ingredients may occur. Hence, this study aimed to evaluate the effect of different ingredients and cooking processes in mercury (Hg) and cadmium (Cd) bioaccessibility in complete meals of tuna (Thunnus spp.) and edible crab (Cancer pagurus), respectively. The addition of ingredients/side dishes decreased Hg levels in cooked tuna meals, but increased Hg bioaccessibility (up to 31% of bioaccessible Hg in complete meals, against 13.5% in stewed tuna alone). Cd levels in edible crab meals were significantly decreased by the addition of ingredients (~36% and ~65% decrease in boiled crab and paté, respectively), but its' bioaccessibility was not significantly affected (>94% in all cases). Results showed that the weekly consumption of 2 complete tuna meals does not exceed MeHg tolerable weekly intake (TWI), whereas Cd's TWI is largely surpassed with the consumption of 50 g/week of edible crab meals. This highlights the importance of determining contaminant levels and bioaccessibility in a whole seafood-based meal context, as such approach enables a more realistic assessment of the risks that seafood can pose to consumers.

Development of black soldier fly larvae (Diptera: Stratiomyidae) on seafood wastes

The black soldier fly,Hermetia illucens (L.) (Diptera: Stratiomyidae) is well suited for remediating biological waste. Larvae of this species are nutrient rich, grow rapidly, and convert organic wastes while suppressing pathogens and pests. Therefore, they could be used in waste management systems and as feed for livestock and in aquaculture. The goal of this study was to test suitability of several seafood wastes from Maine processing facilities forH. illucens development in order to find alternative venues for their utilization. The following substrates were tested under laboratory conditions: dry sea cucumber, wet sea cucumber, crab meal, finfish, dry quahog, wet quahog, and sea urchin (‘wet’ and ‘dry’ refer to the original condition of the wastes while their moisture levels were similar during the experiment).H. illucens eggs were placed on wax paper above each substrate, and larval growth and survival to pupation were measured. Based on the numbers and weights of surviving larvae, substrates potentially suitable forH. illucens rearing included finfish trimmings, wet sea cucumber, dry quahog, and sea urchin. Crab meal produced large larvae (0.091±0.021 g [mean ± SE], compared to experiment-wide mean of 0.064±0.007 g) in a relatively short period of time. However, larval mortality was very high, with only 4.7±1.17 larvae surviving to prepupae, compared to experiment-wide mean of 9.78±0.63 larvae. There were dramatic differences in seemingly similar materials. On wet sea cucumber, 28.82±1.49 larvae per replication survived to pre-pupae, while on dry sea cucumber the number was only 0.33±0.01. On wet and dry quahog, the numbers of surviving larvae were 1.83±0.60 and 10.1±1.97, respectively. This highlights the importance of thorough testing of specific substrates instead of extrapolating from published data.

Socio‐demographic drivers and public perceptions of consumption and conservation of Asian horseshoe crabs in northern Beibu Gulf, China

Abstract Overharvesting Asian horseshoe crabs for food is a primary threat to their populations. In the present study, 451 residents were interviewed from the northern Beibu Gulf, the coastal area that is believed to accommodate the highest density of the Chinese horseshoe crab Tachypleus tridentatus worldwide, to obtain baseline information on their consumption behaviour and underlying drivers. Based on the survey data, it is estimated that a mean individual consumption rate of ten meals per year. Nearly half of the respondents (49.7%) claimed that they had previously eaten at least two horseshoe crab meals. Among the six occupation categories (managers, professionals, workers, environmental‐related workers, fishers and farmers, and students), fishers and farmers were identified as the group that had eaten a significantly higher number of horseshoe crab meals, had consumed them more frequently, and had a greater intention of eating them than that of students. The age, education level, and salary of participants were the important socio‐demographic variables related to their consumption behaviour. More than one‐third of respondents decided to consume horseshoe crabs because they perceived them as tasty ‘seafood’ and valuable ingredients of traditional Chinese medicine. Eighty‐three per cent of participants reported an overall decrease in the number of horseshoe crabs in the region. Although the community was supportive towards horseshoe crab conservation, their ecological knowledge of horseshoe crabs was limited. The findings may be useful for providing insights to merge the gap between scientific data and management planning for the horseshoe crab population in the region. Conservation management initiatives, such as the involvement of fishers in monitoring and enforcement, developing a reporting system for landings and by‐catch, and implementing long‐term conservation education through the school curriculum could promote the protection and management of the population.

Digestibility, growth, blood chemistry, and enzyme activity of juvenile Oreochromis niloticus fed isocaloric diets containing animal and plant byproducts

ABSTRACT In this work, we studied the digestibility, growth, blood chemistry, and enzyme activity of Nile tilapia (Oreochromis niloticus) juveniles (0.95±0.18 g) using different animal (fish silage meal, whey meal, bovine blood meal, and red crab meal) and plant (extruded bean, extruded chickpea meal, coconut paste, Jatropha curcas meal, and chickpea meal) dietary byproducts. Nine isocaloric diets (321.92±9.10 kcal g−1) were evaluated for 60 days. The highest digestibility of crude protein values for animal and plant sources were obtained for [...]

Soil Microbiomes Associated with Verticillium Wilt-Suppressive Broccoli and Chitin Amendments are Enriched with Potential Biocontrol Agents.

Two naturally infested Verticillium wilt-conducive soils from the Salinas Valley of coastal California were amended with disease-suppressive broccoli residue or crab meal amendments, and changes to the soil prokaryote community were monitored using Illumina sequencing of a 16S ribosomal RNA gene library generated from 160 bulk soil samples. The experiment was run in a greenhouse, twice, with eggplant as the Verticillium wilt-susceptible host. Disease suppression, plant height, soil microsclerotia density, and soil chitinase activity were assessed at the conclusion of each experiment. In soil with high microsclerotia density, all amendments significantly reduced Verticillium wilt severity and microsclerotia density, and increased soil chitinase activity. Plant height was increased only in the broccoli-containing treatments. In total, 8,790 error-corrected sequence variants representing 1,917,893 different sequences were included in the analyses. The treatments had a significant impact on the soil microbiome community structure but measures of α diversity did not vary between treatments. Community structure correlated with disease score, plant height, microsclerotia density, and soil chitinase activity, suggesting that the prokaryote community may affect the disease-related response variables or vice versa. Similarly, the abundance of 107 sequence variants correlated with disease-related response variables, which included variants from genera with known antagonists of filamentous fungal plant pathogens, such as Pseudomonas and Streptomyces. Overall, genera with antifungal antagonists were more abundant in amended soils than unamended soils, and constituted up to 8.9% of all sequences in broccoli+crabmeal-amended soil. This study demonstrates that substrate-mediated shifts in soil prokaryote communities are associated with the transition of Verticillium wilt-conducive soils to Verticillium wilt-suppressive soils, and suggests that soils likely harbor numerous additional antagonists of fungal plant pathogens that contribute to the biological suppression of plant disease.

Adsorption and Desorption of Lead (Pb) in Sandy Soil Treated by Various Amendments

The ability of sandy soil to adsorb lead (Pb) to limit its dispersion in environmental compartments and its adverse effects on humans and ecological receptors depends on certain reaction parameters. The sandy soil has a low Pb retention capacity, but treatment of this soil with amendments such as bentonite, crabmeal and eggshells could significantly improve its ability to adsorb the Pb. To this end, various sorbent tests of Pb by sandy soils, soil amendments and soil+amendments have been carried out in a static mode in the laboratory. The adsorption parameters tested are: reaction time, volume/mass ratio, temperature, increasing Pb (II) concentrations, nature and type of amendment. Furthermore, it was under thermodynamic control and was endothermic in the case of an increase in adsorbed and exothermic Pb levels as they decreased. Moreover, the adsorption of Pb obeys the Langmuir model for the soil (R2=0.986), bentonite (R2=0.915) and crab meal (R2=0.790) and Freundlich for eggshells (R2=0.936). The adsorption of Pb as a function of the types and doses of amendment showed that the retention effect of Pb was very significant (p<0.0001) and that 2.5% of crab meal, compared to the minimum intakes of 10% bentonite and 20% eggshells were sufficient to adsorb the maximum Pb for soil treated with a single amendment. The application of two soil amendments showed that the amended soil adsorbed more Pb with the minimum Fe content compared to other amendments. These results show that crabmeal is an excellent biosolid for the retention of anthropogenic Pb. The desorption test demonstrates that Diethylene Triamine Pentacetic Acid (DTPA) extracted much higher amounts of freshly adsorbed Pb than those extracted with ammonium acetate. The amounts of Pb adsorbed were significantly correlated with the amounts of desorbed Pb. Adsorption and desorption are therefore important phenomena controlling the bioavailability of Pb in sandy soils.

Marine and freshwater crab meals in diets for red porgy ( Pagrus pagrus ): Digestibility, ammonia-N excretion, phosphorous and calcium retention

Abstract Two trials were conducted to evaluate the nutrient digestibility of river crab (RC) ( Procambarus clarkii ) and marine crab (MC) ( Chaceon affinis ) meals in diets for red porgy ( Pagrus pagrus ) and the effect on ammonia-N excretion and P and Ca retentions. In trial I, the apparent digestibility coefficient (ADC) of nutrients and energy contents in RC and MC meals were determined. Results showed that, the ADC values for protein, lipids, ash, dry matter and gross energy were significantly higher for MC than for RC meal. Both crab meals were efficiently digested despite their high chitin and ash contents. In trial II, red porgy were fed over 6 months with five diets: a control diet (CD) based on high quality fish meal (FM), and four diets where FM protein was replaced at a rate of 10% or 20% by protein derived from either RC or MC meal (RC10, RC20, MC10 and MC20). Replacement of the FM protein by RC or MC proteins had no effect both on protein utilisation and ammonia-N excretion rates, which ranged from 105 to 119 mg N–NH 4 + kg − 1 day − 1 for all diets. A linear increase was observed in the dietary Ca/P ratio by the increase of the dietary RC and MC meal inclusions, resulting in a reduction in the whole fish body content of P, Ca and ash with interesting similar whole body Ca/P ratio (1.59–1.63) for all treatments. Accordingly, Ca, P and ash retention rates were significantly reduced by increasing the dietary proportion of both crab meals. Moreover, a negative relationship between fish growth and final whole body Ca, P and ash contents was obtained. However, no significant differences were observed in total P excretion value (kg P t − 1 ).

Testing Protein Digestibility in Red Grouper Epinephelus Morio using In Vitro and In Vivo Methods

The digestibility of pre-selected ingredients was evaluated for Epinephelus morio using pH-stat and multi-enzyme extract (stomach, intestine, and ceca). The degree of hydrolysis (DH) was tested with acid and alkaline proteases using crustacean meals, squid meal, fish protein concentrate (FPC), fish meal, dried whey, as well as canola paste (w/ or w/o phytase), soybean meal (w/ or w/o phytase), soyprotein concentrate (SPC), and wheat gluten. SPC produced DH values between 3.6-4.1%, obtained from the three different parts of the digestive tract. Canola paste produced high DH in the stomach by adding phytase to 0.8 and 2% feed. This process was repeated under alkaline conditions for DH, with 0.6-2.6% in the pyloric ceca, and 1-2.2% in the intestine. The DH from stomach with crustacean meals (shrimp meal and crab meal) ranged from 32-87%, while values for dried whey from the ceca and intestine ranged from 6-7.4%. It did not differ from crab meal with values of 4.5 and 8.7% from pyloric ceca and intestine respectively. Based on the above results, 4 diets were developed using shrimp meal, dried whey, soy protein concentrate, and canola+phytase. The DH, FAA (fish amino acid) and SDS-PAGE (analysis of protein gels) for each diet were analysed. After an in vivo test, results on juveniles fed whey protein diet (WPd) and CPd+ ranked high (95% and 92% respectively) compared with other treatments. pH-Stat provided consistent results regarding digestibility of selected protein sources. Therefore, dried whey, shrimp meal, and canola+phytase ranked first to be included in E.morio feed formulation with a pool of 55% of these components, complemented with a minimum of fish meal, FPC, grains and wheat gluten

Effect of dietary substitution of fish meal for marine crab and echinoderm meals on growth performance, ammonia excretion, skin colour, and flesh quality and oxidation of red porgy (Pagrus pagrus)

Abstract The present study was conducted to evaluate the effect of feeding marine crab (SMC) meal and sea urchin (SU) meal on growth performance, ammonia-N excretion, skin colouration and final flesh quality and lipid oxidation of red porgy ( Pagrus pagrus ). Fish were fed with five diets: a control-diet (CD); two diets replacing 10% and 20% fish meal protein by protein from SMC meal (SMC10, SMC20), and two diets with 8% and 16% inclusion of SU meal (SU8, SU16). The inclusion of both SMC and SU meals increased fish appetite response reflected in a significantly higher feed intake and final weight. Results were even better for fish fed on SU diets, with improved feed conversion (FCR) and protein utilization (PER). Ammonia-N excretion rates decreased in fish fed on SMC20, SU8 and SU16 diets. Fish skin colouration improved by SMC meal inclusion, while SU meal promoted yellowness colouration in skin. Higher muscle content of arachidonic fatty acid (ARA), was concomitant with the increased level of SMC in diets. The same trend was also found in fillet of fish fed on SU meal diets, with the highest values in ARA content. Results of TBARS in raw fillets showed that the dietary inclusion of SMC meal delayed lipid oxidation compared to FM and SU diets during refrigerated storage.

Marine and freshwater crab meals in diets for red porgy (Pagrus pagrus): Effect on fillet fatty acid profile and flesh quality parameters

The present study was conducted to evaluate the effect of using river crab (Procamburus clarkii) meal (RC) and marine crab (Chaceon affinis) meal (MC) on the red porgy (Pagrus pagrus) fillet fatty acid profile and quality. Red porgy were fed during 193days with five diets: a control diet based on high-quality fish meal (CD); and four diets replacing 10% and 20% fish meal protein by protein from both RC and MC meals (RC10, RC20 and MC10, MC20). Fillet fat content resulted significantly higher in MC20 fish than the rest of diets. Feeding with both RC and MC meals slightly increased muscle contents of polyunsaturated (PUFA), arachidonic (ARA), eicosapentaenoic (EPA), and docosahexaenoic (DHA) fatty acids and n−3/n−6 ratio as well as decreased n−9 fatty acids, although difference is only significant for the ARA content. After inclusion of both crab meals, values of atherogenicity index (AI) resulted similar among treatments while thrombogenecity index (TI) was reduced, but not significantly, reflecting the higher n−3 fatty acid content in fillets from crab diets. Sensory analysis showed that red porgy fillets of all treatments were very well appreciated with some differences detected in only MC20 fillets, which had significantly higher scores in the attributes of oily odour and flavour, cohesiveness aspect and firmness texture compared to the rest of diets. RC meal dietary inclusion did not promote any changes in sensory evaluation panel. Instrumental muscle texture did not revealed differences between treatments. Results from TBARS of raw fillets showed that the inclusion of both crab meals clearly delays lipid oxidation compared to a FM based diet, during refrigerated storage at 4°C. Thus, for 4 and 7days of storage, fillets of RC or MC diets, attained significantly lower TBARS values than those fed on CD.

FERTILITY RATE AND TIMING EFFECTS ON ORGANIC BLACK CURRANT GROWTH AND YIELD DURING ESTABLISHMENT

A study on Prince Edward Island was initiated to assess the impact of organic fertility amendment rate and timing treatments on the growth, yield, berry size and soluble solids of black currants (Ribes nigrum ‘Titania’). Bushes were planted in the spring of 2009 at two sites with black plastic mulch as a weed control without irrigation, and fertilized with seven fertility treatments in either the spring, the summer or split between spring and summer. Rates were 50, 100 and/or 150 kg estimated available N from a blend of crab meal and poultry manure (Nutriwave®). Yield and berry soluble solids were measured in 2010 and 2011. Plants at the site with leaf P and K deficiencies showed lower growth and yield (492-2,540 kg ha-1), but had significant differences in growth response to amendments compared with the site that had adequate levels of P and K, which had no significant difference among treatments in yield in 2011 (3,935-5,016 kg ha-1) or growth among treatments in any of the three years. Where significant differences in growth were found, the medium spring fertility treatment gave the greatest growth and yield, followed by the high spring fertility treatment. The high spring treatment had the highest growth in 2010, but the lowest growth and yield in 2011.

The effects of replacement of fish-meal with crab-meal on growth and feed utilization of African giant catfish Heterobranchus longifilis fingerlings

A feeding experiment was conducted in plastic aquaria (46 ´ 38 ´ 28 cm3) to investigate the effect of replacing fish-meal (FM) with crab-meal (CM) on growth, feed utilization and body composition of Heterobranchus longifilis fingerlings with body weight, 3.11 ± 0.56 - 8.48 ± 1.70 g and total length, 73.07 ± 4.99 - 98.69 ± 7.64 mm. Fish and crab-meal were separately used to produce feeds containing 30, 35 and 40% crude protein (CP) and fed to fish for 10 weeks at 5% body weight. The results show that fish fed with 40% CP fish-meal diet had the best growth as indicated in mean weight gain, 6.99 ± 1.70 g; specific growth rate, 4.05 ± 0.19% day-1; feed conversion ratio, 1.12 ± 0.06 and protein efficiency ratio of 2.28 ± 0.12. Diets with FM performed better than CM diets. Percentage survival rate for FM and CM containing diets varied between 91.0 ± 1.63 and 100% and the condition of fish was not significantly different (P > 0.05). Apart from whole body levels of CP in FM fed fish, moisture and fat contents were unaffected by dietary treatments. Deficiency in some essential amino acids and higher dietary ash levels in CM probably impaired effective utilization of these diets compared to FM. Crab-meal diets show appreciable performance and could have potential use as a partial replacer of FM at a particular level. Key words: Heterobranchus longifilis, fish-meal, replacement crab-meal, growth, food utilization.

Potential of crab meal as a protein substitute for fish meal in diets for mudfish Heterobranchus longifilis juveniles

A study aimed at evaluating the suitability of crab meal as a potential substitute for dietary fishmeal protein for mudfish (Heterobranchus longifilis ) juvenile was carried out. Fishmeal (FM) and crab meal (CM) protein sources were used separately to prepare diets containing 30, 35 and 40% crude protein (CP). The diets were fed to fish at 5% body weight for 70 days in plastic aquaria. Crab meal at 30% CP level showed a performance of approximately 56.6% (percent weight gain), 50% (specific growth rate, protein efficiency ratio and apparent net protein utilization) of FM containing diet of 30% CP but was similar in fish condition, 0.62 ± 0.005 and 0.66 ± 0.005 for CM and FM diets. Fish survival was 100% for all experimental diets. The feed conversion ratio was appreciable, 4.50 ±1.38 for CM compared to 2.60 ± 0.65 and 1.94 ± 0.65 for 30% and 35% protein fishmeal diets. Inadequate essential amino acid balance and digestibility could be responsible for the reduced performance of crab meal compared to fishmeal. Crab meal has potentials and future trails on partial replacement of FM could reveal improved performance on H. longifilis .

Paragonimiasis Reemergence in Nigeria: Predisposing Factors and Recommendations for Early Intervention and Everlasting Eradication

Effective paragonimiasis eradication programme in Nigeria eradicated the once endemic disease and no case was reported from 1980 to 2007. The first reported reemergence case was in 2007 and five more cases till January 2011 when this study was undertaken. This study is to determine the pre-disposing factors for the reemergence. The factors will help plan a sustainable long lasting and hopefully everlasting eradication programme. 2760 households from the identified twelve villages with the endemic disease were systematically selected. Pretested questionnaires were interviewer administered to the head of each of the selected household. The data collected were analyzed quantitatively and qualitatively. The pre-disposing factors that precipitated the reemergence of the disease included low level of awareness of the disease by the entire populace including the health workers. This included the causative agent, the mode of transmission, and control; conservative cultural habits of preparing crab meal; eating improperly cooked crab and also insanitary disposal of faeces and sputum. A holistic eradication programme should be planned to have sustained activities that will usher in everlasting disease-free area. The programme should involve all people, policy makers, health workers, and the entire populace, taking care of peculiarities of the peoples habits.

Evaluating by-products of the Atlantic shellfish industry as alternative feed ingredients for laying hens

A full-cycle laying hen study was conducted to evaluate crab meal (CM) and lobster meal (LM) as feed ingredients for laying hens by assigning four hundred thirty-two 35-wk-old White Leghorns to 1 of 6 diets [control, 2.5% CM, 2.5% LM, 5% CM, 5% LM, and 2.5% CM + 2.5% LM (blend)]. Productive performance and egg parameters were evaluated every 28-d period. Eggs were collected at 67 wk of age from the 5% CM, 5% LM, and blend treatments for analysis of yolk fatty acid composition. At 55 and 67 wk of age, ulnas were collected to determine breaking strength, percent ash, and calcium. Body weights, feed consumption, hen-day production, feed efficiency, and egg quality were not affected (P > 0.05) by treatment. The L* scores of eggs from 5% CM, 5% LM, and blend were lower (P < 0.05) than eggs from the control by the end of the second 28-d period. The a* score of the eggs from 5% CM, 5% LM, and blend was higher (P < 0.05) than the control by the end of the first 28-d period. The content of docosahexaenoic acid (DHA) in egg yolks was different (P < 0.05) among the control (0.17 g/100 g), 5% CM (0.46 g/100 g), 5% LM (0.32 g/100 g), and blend (0.38 g/100 g) treatments. Treatment did not affect (P > 0.05) any of the bone parameters measured at 55 and 67 wk of age. CM and LM supported similar egg production, feed efficiency, egg yolk color, adequate bone strength, and the incorporation of DHA into egg yolks.

Organo-mineral fertilization in natural peatlands of the Quebec North-Shore, Canada: Dispersion in soil and effects on cloudberry growth and fruit yield

Natural peatlands are an important source of berries in northern countries. One possible avenue to improve crop yield in natural peatlands is to apply fertilizers, ombrotrophic peatlands being very low in nutrients. In order to reduce the impact of this practice on an otherwise natural habitat, slow-release organic fertilizers might be more appropriate than mineral fertilizers. However, mineralization and dispersion of organic fertilizers in peatlands need to be determined along with their impact on crop yield. In the present study, we focused on cloudberry fruit that despite a high commercial potential is limited by low and variable yield. We thus tested the effect of an organo-mineral fertilizer in two peatlands on nutrient dispersion, plant growth, flowering frequency and fruit yield of cloudberry. The organo-mineral fertilizer, composed of crab and fish meal supplemented with potassium chloride, was applied annually for three years. The treatment was repeated in two natural ombrotrophic peatlands: one covered with lichen and the other a more typical sphagnum bog. The dispersion study indicated very limited dispersion of most nutrients. There was no effect of the fertilizer on cloudberry growth and fruit yield or on the nutrient concentrations of its tissues. We concluded that the fertilizer did not mineralize to sufficient extent. Mineralization of potential organic fertilizers would need to be tested in natural peatlands before being applied to cloudberry patches.