Post-harvest technology

In recent years great interest is envinced in several countries in the culture of molluscan shellfish. In the tropics favourable conditions exist for rapid growth and marketable oysters are obtained with in vir^n to twelve months. Investigations have been conducted at the Central Marine Fisheries Research institute and success has been achieved in perfecting the techniques of oyster culture in coastal waters (Nayar and Mahadevan, 1983). The awareness that shellfish have to be purified and rendered harmless goes back to the time of the Roman Empire. During the first century B.C. the Romans consumed cockles and oysters after treating them in tanks known as cockle washery (Yonge, 1962)

Single Point Fixation Vs Two Point Fixation in Zygomatic Complex Fractures by using Titanium Mini Plate: A Comparative study

PURPOSE: The aim of this study was to evaluate the action of splint therapy on the muscles of mastication namely Temporalis and Masseter in patients with temporomandibular joint dysfunction syndrome using a muscle force transducer. MATERIALS AND METHOD: This is a prospective study in fifteen patients reporting to, Ragas Dental College and Hospital, Chennai, Out Patient diagnosed with untreated temporomandibular dysfunction syndrome between 18 and 60 years of age. All the patients included were in the early stages of the disorder and were only treated with a conservative approach by means of medications and splint therapy. Advanced stages of dysfunction was not included in this study as at least minimal surgical intervention would have been required. An MRI was done for these cases to rule out advanced stage of disease following which patient specific splints were provided. A muscle force transducer was attached over the masseter and temporalis muscles independently and the muscle activity was recorded at the time of presentation of the disorder, 1 month, 2 months and 3 months after delivery of the splints. Along with muscle activity gender prevalence, pain scores, severity of disorder, presence of impacted third molars, parafunctional habits and effectiveness of the treatment were also evaluated RESULTS: The Study Revealed that TMJ dysfunction had a female predilection and was closely associated with patients having impacted third molars and parafunctional habits. An overall reduction in the pain score and muscle activity was seen in all the patients. Muscle activity values that reverted back to the normal range was seen in 14 of the 15 patients. CONCLUSION: It can be concluded that splints play an important role in relieving patients with TMJ dysfunction syndrome. The transducer can be used as an efficient diagnostic tool to record muscle activity and to objectively determine the duration of splint therapy rather than solely relying on subjective evaluations

Larval rearing and production of spat of the oyster Crassostrea madrasensis (Preston) in an Experimental hatchery

The Indian backwater oyster, Crassostrea madrasensis, was spawned in the laboratory at Tuticorin. The larvae were reared and the spat settled in 15-20 days. Two species of jihytoflagellates, Isochrysis galbana and Pavlova sp. were isolated from the natural environment, cultured in mass scale and given as food throughout the larval period. Early stages of the development of fertilized egg, successive stages of developing larvae, and metamorphosis to the spat have been described. The methodology of the production of cultchless spat and rearing the post-set oysters are discussed

Indian edible oyster

In India pioneering attempts were made by James Hornell in 1910 in developing Oyster culture in the erstwhile Madras State. Scientific investigations were undertaken during early 70's by the Central Marine Fisheries Research Institute, at Tuticorin. The Institute has conducted R & D programmes on all aspects of Oyster farming during the last two decades, culminating in a wealth of informations on the technology of Oyster farming. The Brochure outlines various aspects of the technology of farming of the Indian Edible Oyster or the Indian Backwater Oyster Crasaostrea madrasensis (Preston} including information on biology, ecology and economics of Oyster farming

The edible oyster culture

In 1970s the CMFR Institute initiated oyster culture through rack and tray method. Large scale spat collection, preparation of spat collectors, season and seed availability were studied. In 1980, a hatchery was set up with annual production capacity of one million edible oyster seed and the techniques involved in hatchery system were standardized. The seed were supplied to other centres of this Institute and Gujarat Fisheries Department. The production rates for rack and tray, string and stake method were estimated as 120 t and 22 t respectively. As part of extension, one lab to land programme, 8 training programmes, one workshop and a summer insitute were conducted. Results of experimental oyster culture work carried out at Mandapam, Madras, Bheemunipatnam, Kakinada, Mulki, Dharmadam, Ashtamudi and Cochin backwaters are given. Rearing 600 strings in 0.04 ha at Ashtamudi and harvesting 2.5t oysters pointed out 44.8% return with estimated production of 80- 105t/ha. Further research priorities on oyster culture aspects are indicated

Air Pollution Tolerance Index and Biochemical constituents of some plants growing in Neyveli Lignite Corporation (NLC), Tamil Nadu, India

Abstract Plant species can be effectively used as filters to reduce air pollution and also as bio-indicators of urban air quality. Screening of plants for their sensitivity/tolerance level to air pollutants is important because the sensitive plants can serve as bio-indicator and the tolerant plants as sink for controlling air pollution in urban and industrial areas. Biochemical parameters namely Relative Water Content, leaf extract pH, ascorbic acid, chlorophyll, starch, protein, amino acid, reducing and total sugar were estimated to generate Air Pollution Tolerance Index (APTI) for ten plants each at polluted site and control site. The results showed that Terminalia catappa (18.16 and 16.19) and Mangifera indica (16.01 and 15.98) have recorded high and low values in both the sites respectively. In comparison between the two sites, all the values were slightly higher in the polluted site than the control for all the ten plants and a considerable variation was observed among the four parameters where their percentage variations were considered. Terminalia catappa, Mangifera indica and Calotropis gigantea were found to be tolerant towards air pollution

Distribution and exploitation of oyster resources along the southeast and southwest coasts of India

The oysters are sedentary bivalve molluscs which are gregarious and found in aggregates attached by their right shell valve to hard substrata, forming oyster beds or oyster banks in varied environments, intertidal and subtidal zones in shallow coastal waters, bays, creeks, lagoons, backwaters and estuarine environment. In India, natural stocks of oysters are exploited on a small scale at a number of places as a subsistence fishery and oysters are not cultured commercially

Environmental characteristics of edible oyster beds in and around Tuticorin

The investigations on various hydro-biological parameters which influence the condition factor, spawning and the resource characteristics of the edible oyster Crassostrea madrasensls around Tuticorin have been conducted in three habitats of oyster beds, namely coastal (Tuticorin Bay), mangrove (Korampallam Creek) and estuarine (Punnakayal) areas. Observations on the stages of maturity, spawning and condition of oysters in the three habitats have been made and a correlation of the above biological aspects of the oysters with the environmental factors have been attempted. A direct correlation has been observed between the biological aspects of oysters and the productivity parameters of the habitat. The water temperature also showed a direct relationship with the condition factor of the oysters. The mean value of the condition factor of the oysters were found to be at the optimum level during April when productivity parameters were observed to be at higher level. The chemical factors especially the nutrients such as nitrates and phosphates showed an indirect relationship with maturity and condition of the oysters. Among the different habitats, the mangrove area registered higher productivity rates which has a well defined relation with the condition of oysters

Induced spawning and larval rearing of Crassostrea madrasensis (Preston) in the laboratory

The technology of culturing the edible oyster Crassostrea madrasensis by rack and tray method has been developed. Investigations on induced spawning and rearing of the oyster lead to produce spat of Crassostrea madrasensis on a large scale for the first time in India.The spawning of oysters were done in suitable conditions and the fertilised eggs undergone larval rearing,each stage is examined carefully and discussed, to complete the development within 19 days

Successful induced spawning and rearing of the holothurian Holothuria (matriatyla) scabra Jaeger at Tuticorin

The Central Marine Fisheries Research Institute, ventured upon a programme on the artificial breeding and production of seed for culture and propagation of the commercially valuable holothurian species. The Institute's success on the above aspects under controlled conditions by thermal stimulation is significant which may eventually solve the problems presently faced by the beche-de-mer industry in India. This is the first time that such work is carried out in India