ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1985.tb00403.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1985.tb00404.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

SummaryIn the first half of the paper a review is given of the occurrence and migratory habits of Baltic cod based on experience since the 1950s, results of extensive tagging experiments combined with information on changes in allele frequency for haemoglobin types, in meristic characters, and in otolith types. The latter pan of the paper is an account of about 15 transplantation experiments with tagged cod to study a potential homing ability of the fish.The very great importance of the threshold areas inside the Baltic and out to the Kattegat is stressed, and so are the hydrographic conditions in general for cod recruitment and migration. The waters west of Bornholm constitute an area of hydrographic instability with varying cod migrations and passive transport of fry with the currents. The migration east of Bornholm refers—except for local stocks and a varying contribution from the west‐mainly to fish grown up in the central Baltic proper and northern areas. The latter fish migrate primarily southward for spawning, and as adults they usually stay in the southern waters east and north of Bornholm.The results of the transplantation experiments support a strong direct linkage of cod migration and hydrographic factors. Cod that were tagged and transplanted to a new area behaved and moved in the same way as the local stock. Indications of “homing” can be found in areas with suitable hydrographic gradients, such as changes in salinity, for example in the

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1985.tb00405.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

SummaryGrowth and food intake of juvenile flounders from the Kiel Bight were measured experimentally at different salinities (0, 5, 15 and 35 %). The growth at the middle levels (5 and 15 %) was faster then at 0 and 35 %. The reason for lower rates of increase in the freshwater group is the lower food intake. In the 35 % group the slower growth is caused by the worse food conversion. The variance of the individual growth rates in the 15 % salinity group remains far below the values of all other groups.

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1985.tb00406.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

SummaryThe influence of temperature on growth, feed conversion, and protein and gross energy utilization was assessed in two experiments using the European catfish,Silurus glanisL. Animals of 55 g and 24 g were used in trials lasting 6 and 7 weeks, respectively. The optimum temperature for growth was within the range of 25 to 28°C, with the best results obtained at 27°C. Using à feed of low protein content (30.3%), a feed conversion of 1.67 was achieved at à specific growth rate of 1.78% of body weight/

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1985.tb00407.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

SummaryNovel gene which was microinjected into fertilized eggs of the goldfish replicated during the embryogenesis. A proportion of the novel gene has been integrated into the host DNS of the 50‐day‐old transgenic goldf

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1985.tb00408.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

SummaryHistopathological study of infections withCryptobia iubilansNohýnková 1984 in two species of freshwater aquarium cichlids (Herichthys cyanoguttatumandCichlasoma meeki) revealed severe tissue changes which were not limited to the digestive tract but also affected other principal body organs. The lesions were extensive enough to cause mortalitiesC. iubilansis thus far the only clearly pathogenic species among cryptobias infecting fis

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1985.tb00409.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

SummaryThe influence of water‐borne iron (500 μg × 1‐1and 2 mg × 1‐1) on the liver ofPoecilia reticulatais studied by means of electron microscopy. The uptake and effect of iron is affected by a. the chemical speciation of the metal: Iron complexed with tri‐polyphosphates is more deleterious than inorganic Fe3+; b. the nutritional status of the fish: In food‐deprivedPoecilia reticulatairon is absorbed and enhances starvation‐induced liver damage. In fed animals, there is no uptake at all. Mild alterations of hepatocyte ultrastructure are attributed to an unspecific s

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1985.tb00410.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

The Freshwater Fishes of China in Coloured Illustrations.(Vol. 1). Co‐edited by the Research Institute of Hydrobiology, the Chinese Academy of Science and the Shanghai Natural Museum, published by the Shanghai Science Press, 198

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1985.tb00411.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY