Some immunobiological aspects of the spiny lobster Panulirus homarus (Linnaeus, 1758)(TH 114)

Panulirus homarus (Linnaeus, 1758) being a species of great commercial importance fetches high demand in the international market. The demand of live lobsters depends on the health status of the animals. Study on the defence mechanisms in P. homarus showed three cell types in the haemolymph: hyaline cells, semi granular cells and large granular cells. The haemocy1es are produced from the haematopoetic tissue located in the epigastric region, they are lobular with a size range of 30-875 jJm. The immune status of healthy lobsters showed that the total haemocy1e count was 8.7 ± 3.8 x 106 cell mr l and the phenoloxidase activity 30.61 ± 5.6 IU mg protein- 1 • Studies on physiological stress like moulting, eyestalk ablation showed variation in the immune parameters (P < 0.05) . Upon starvation the THe and PO activity was found to decrease drastically. Feed trials showed that mussels, the preferred diet of lobsters was found to show better immune response over those fed with fish diet. Environmental stress factors like salinity, pH, dissolved oxygen and ammonia showed significant effect on the immune system of P. homarus. Live transportation of lobsters by dry method was found to suppress the PO activity but no change was seen in THe. Injection studies with bacteria showed the lowest peak during 30 minutes incubation for THe whereas it showed highest peak for PO activity for the same incubation time. Both THe and PO levels came back to normal after 24 hours. On injection with laminarin an immunostimulant similar result was obtained. Farm made artificial feed supplemented with chitosan was found to enhance the activity of the immune system . Satisfactory result for immune enhancement was not observed with commercial immunostimulant supplement. Analysis of serum PO activity and total haemocy1e count can be used as indicators of the health in crustaceans, which can be monitored, even in farm conditions. Routine monitoring of health status is of great importance with regard to successful aquaculture practices

Electrophoretic patterns of the general proteins of four species belonging to the Family Carangidae.

Muscle proteins usually provide useful information and therefore are frequently used as valuable diagnostic characters in the classification of fishes at species, generic, familial and higher taxonomic levels. The muscle myogen of four species of carangids. viz, Decapterus russelli, D. macrosoma, Selar crumenophthalmus and Megalaspis cordyla using horizontal slab polyacrylamide gel electrophoresis (Gel conc. 7.5%) is reported in the present communication. The number of protein fractions and the presumptive loci in muscle of D. russelli, D. macrosoma, S. crumenophthalmus and M. cordyla were found to be 9,7,6 and 5 respectively. The Rf value ranged from 21 to 84 for S. crumenophthalmus, 2 to 72 for M cordyla, 15 to 89 for D. macrosoma and 18 to 96 for D. russelli. The difference in number of fractions, their mobility pattern and staining intensity indicated species-specificity. With the limited number of samples used in the present work, there has been an indication of intraspecific polymorphism among three species of carangids, being 3.5% in D. russelli, 13.5% in D. macrosoma and 6.6% in S. crumenophthalmus. In M. cordyla no polymorphism was observed. This work also revealed that protein fractions in carangids can be used as species - specific markers, which could be helpful in resolving disputes in the event of any taxonomic ambiguity

Effect of moulting, eyestalk ablation, starvation and transportation on the immune response of the Indian spiny lobster, Panulirus homarus

The Indian spiny lobster, Panulirus homarus (Linnaeus 1758), is of great commercial importance and has a high demand in the internationalmarket.However, due to the lack of larval rearing technology, traders depend heavily on the wild-caught undersized lobsters that are normally maintained in impoundments for fattening. Overstocking and poormanagement of these holding and fattening systems can result in stress, which can eventually lead to disease outbreak. Crustaceans respond to these stress factors with their innate immune system, consisting of bothcellularand humoral factors

Electrophoretic patterns of sarcoplasmic proteins in carangid fishes

The present paper reports muscle myogen patterns of four species of carangids, viz. Decapterus russelli, D. macrosoma, Selar crumenophthalmus and Megalaspis cordyla using horizontal slab polyacrylamide gel electrophoresis. The number of protein fractions (presumptive loci) in the muscle of D. russelli, D. macrosoma, S. crumenophthalmus and M. cordyla were found to be 9, 7, 6 and 5, respectively. The Rf value ranged from 21 to 84 in S. crumenophthalmus, 2 to 72 in M. cordyla, 15 to 89 in D. macrosoma and 18 to 96 in D. russelli. The difference in number of fractions, their mobility pattern and staining indicated species-specificity. With the limited number of samples used in our study, there has been an indication of intraspecific polymorphism among three species of carangids, being 3.5% in D. russelli, 13.5% in D. macrosoma and 6.6% in S. crumenophthalmus. M. cordyla showed no intraspecific polymorphism. The study reveals that protein fractions in carangids can be used as species-specific markers, which could be helpful in resolving disputes in the event of any taxonomic ambiguit

Adaptive evolution after duplication of penaeidin antimicrobial peptides

Penaeidin antimicrobial peptides in penaeid shrimps are an important component of their innate immune system that provides immunity against infection caused by several gram-positive bacteria and filamentous fungal species. Despite the knowledge on the identification and characterization of these peptides in penaeid shrimps, little is known about the evolutionary pattern of these peptides and the underlying genetic mechanisms that maintain high sequence diversities in the penaeidin gene family. Based on the phylogenetic analyses and maximum likelihood-based codon substitution analyses, here we present the convincing evidence that multiple copies of penaeidins have evolved by gene duplication, and positive Darwinian selection (adaptive evolution) is the likely cause of accelerated rate of amino acid substitutions among these duplicated genes.fisheries of the country has led to a remarkable increase in fish landings, the problem of by-catch and targeted juvenile fishing is ever increasing. The present analysis shows that the contribution in the form of annual average profit by various craft–gear combinations is often not sufficient to compensate the overall loss generated by the same to the fishery through the harvest of juvenile fishes. Even though the fishermen gain some transient economic incentives from the juveniles landed, the estimated economic loss calculated was at about US$ 19,445 million year−1 from the mechanised as well as motorised sector. Both intergenerational and conventional discounting was applied to show the net present value (NPV) of future loss due to juvenile fishing. Some of the less capital intensive gears also substantially contribute towards the economic deficit caused by juvenile fishing. We suggest that, while considering the ecosystem impacts of accidental by-catch and intentional juvenile fishing, the economic impacts also should be taken into account prior to formulating any management measures. The study provides an insight to the cost of juvenile fishing in a multi-species multi-gear fishery, where a homogeneous management system is ineffective. The possible causes of increased growth overfishing in the country and subsequent economic loss to the industry are also discussed

Not Available

Not AvailableThe present paper reports muscle myogen patterns of four species of carangids, viz. Decapterus russelli, D. macrosoma, Selar crumenophthalmus and Megalaspis cordyla using horizontal slab polyacrylamide gel electrophoresis. The number of protein fractions (presumptive loci) in the muscle of D. russelli, D. macrosoma, S. crumenophthalmus and M. cordyla were found to be 9, 7, 6 and 5, respectively. The Rf value ranged from 21 to 84 in S. crumenophthalmus, 2 to 72 in M. cordyla, 15 to 89 in D. macrosoma and 18 to 96 in D. russelli. The difference in number of fractions, their mobility pattern and staining indicated species-specificity. With the limited number of samples used in our study, there has been an indication of intraspecific polymorphism among three species of carangids, being 3.5% in D. russelli, 13.5% in D. macrosoma and 6.6% in S. crumenophthalmus. M. cordyla showed no intraspecific polymorphism. The study reveals that protein fractions in carangids can be used as species-specific markers, which could be helpful in resolving disputes in the event of any taxonomic ambiguityNot Availabl

Not Available

Not AvailableNot AvailableNot Availabl

Not Available

Not AvailableThe Indian spiny lobster, Panulirus homarus (Linnaeus 1758), is of great commercial importance and has a high demand in the internationalmarket.However, due to the lack of larval rearing technology, traders depend heavily on the wild-caught undersized lobsters that are normally maintained in impoundments for fattening. Overstocking and poormanagement of these holding and fattening systems can result in stress, which can eventually lead to disease outbreak. Crustaceans respond to these stress factors with their innate immune system, consisting of bothcellularand humoral factors.Not Availabl

Not Available

Not Availablehe high export value of the Indian spiny lobster Panulirus homarus increasingly attracts the aquaculturists for farming and fattening. However, lack of knowledge on the effect of environmental parameters on the immune system of this animal could result in high mortality, which ultimately may cause major loss to the industry. Here, we report the effect of salinity (20, 25, 35, 40, and 45‰), pH (5.0, 8.0, and 9.5), dissolved oxygen (DO) (1 and 5 mg L−1), and ammonia-N concentration (0, 0.5, 1.5 and 3 mg L−1) on the immune response of P. homarus measured in the haemolymph in terms of Total Haemocyte Count (THC), phenoloxidase (PO) activity, and NBT-reduction. Our data showed significant reduction (P < 0.05) in THC, and NBT-reduction at lower (20‰) and higher (45‰) salinities. However, PO activity showed significant disparity, showing an increasing trend from 20 to 45‰. Significant reduction (P < 0.05) in THC and PO activity under acidic and alkaline conditions, under hypoxic condition (1 mg L−1), and at the higher ammonia-N concentrations than their respective optimal conditions were observed. Thus, suggesting that extreme environmental parameters can induce modifications in the immune system of the spiny lobster P. homarus, which may enhance their susceptibility to opportunistic pathogens. The humoral parameters such as THC, PO activity, and NBT-reduction can be used as potential stress indicators for healthy management of spiny lobsters.Not Availabl