Eine zusätzliche Möglichkeit für die Ostseedorsch-Fischerei: Steerte aus 90° gedrehtem Netztuch

In 2004, comparative selectivity investigations were made with the now legal BACOMA codend of 110 mm mesh opening and alternative codends made of netting turned 90° of similar mesh openings on both commercial boats and on research vessels. The results show a certain variability of the BACOMA results – depending on ship type and season (L50 varying between 36,8 and 40,6) – and a general equal efficiency of codends made of netting turned 90° of the same mesh opening. Underwater observations and reduced performance of codends of equal circumference in meshes as the joining round at the end of the tapered part of the trawl indicate the need to reduce the relation of the cir-cumferences of codend and extension to 1 to 0.7 to achieve optimum fit and selectivity.

Morphometric studies in Penaeus merguiensis from Ratnagiri waters for selection of the brood stock in genetic improvement programmes

Studies on genetic improvement of penaeid prawns for the character higher tail weight using methods of selective breeding were undertaken. Prior to the actual breeding experiments it was necessary to find out the quantum of available variability in the character tail weight amongst the natural populations of Penaeus merguiensis from the Indian waters. Thirteen morphometric variables were measured and various statistical analyses were carried out. The tail weight showed almost double values of coefficient of variation in the females than the males (C.V. 20.37 and 11.08 respectively). The combination of the characters viz. sixth segment length (SSL), sixth segment depth (SSD) and posterior abdominal circumference (PAC) gave the highest R super(2) values. These variables were easy to measure and gave maximum variation in the character tail weight without sacrificing the breeders in the brood stock. The quantitative character tail weight was influenced by both genetic and environmental factors was statistically ascertained by applying 2-Factor analysis.

Nutritional evaluation of an indigenous low cost protein food

A study of supplementary feeding was conducted on children with a protein food (edible fish powder in the form of 'chutney') for 35 days and the effect assessed periodically. The most noticeable effect was gain in weight and mid arm circumference in children. 35% children showed a weight gain of 1 kg, 27% 0.5 kg, 21% 1.5 kg and 2.5% 2.5 kg. 48% children registered an increase in their mid-arm circumference by 0.5 cm, 16% 1 cm and 2.5% 1.5 cm. 10% children did not gain weight. However, these children had intercurrent infections like measles, whooping cough and asthma.