摘要:

SummaryThe intestine of Mugilidae (Pisces; Teleostei) at different growth stages.I. Morphological and histological aspectsA morphological and histological study of the intestine of Mugilidae (Mugil cephalus, Liza aurata, Liza ramadaandLiza saliens) has been carried out from the larval to the adult stages. The allometric relationship between length of intestine and standard length of fish are represented by regression lines correlated with species and kind of diet. S.E.M. observations on the intestinal mucosa surface show finger‐like villi, as in Mammals. Histologically, the mucosa structure appears similar to that in others Teleosteans. The gobblet cells are scarce in the larval stages but very numerous in the juvenile stages; furthermore, they are more abundant in the posterior than the anterior part of the intestine (respectively 25 and 10%). Change in the feeding habits observed in young stages has no effect on the features of the intestine but notably increases its relative lengt

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1987.tb00443.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryThe following treatments were evaluated for use in rearing pikeperch larvae (Stizostedion luciopercaL.) in nursing ponds: treatment with Dipterex (Bayer); concurrent stocking with common carp (Cyprinus carpioL.); short flooding periods and prefeeding fish larvae. Treatment with Dipterex (active ingredient trichloorfon, i.e. 00‐dimethyl‐2,2,2, trichlorohydroxyethyl phosphonate) gave zooplankton populations dominated by rotatoria and nauplii at the onset of exogenous feeding and dominated by copepods later on. Cladocerans dominated the plankton in untreated ponds but were never prominent in treated ones. Stomach analysis revealed a fast changing feeding preference in pikeperch from nauplii and copepodites towards cladocerans and chironomids. The excellent food conditions for first feeding pikeperch larvae in Dipterex treated ponds resulted in a significant higher number of harvested fingerlings. In spite of the more favourable food conditions in untreated ponds during the second half of the culture period, a significant growth difference was not found. Concurrent carp stocking did not affect significantly the survival and growth of the pikeperch, although it decreased the accessability of chironomids for pikeperch. Short flooding periods and prefeeding pikeperch larvae failed as useful management strategies for pikeperch nursing. Pikeperch fingerlings cultured in ponds are larger than those found in natural populations at the same time, giving them a high chance to become piscivorous and to increase the year class strength when stocked in natural wat

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1987.tb00444.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryIn our effort to give some information which investigates autecological parameters for southern barbel, a study of age, growth and reproduction for this species was carried out in the Rentina stream, northeastern Greece. The length‐weight relationship can be described by the equations W = 0.008 L3.159and W = 0.0583 L2.428for females and males, respectively (W = body weight in g, L = fork length in cm). The most rapid growth in length occured during the first year of life (7.3 cm) after which growth decreased and remained constant at approximately 3.4 cm per year. The average density and biomass were 0.25 fish. m‐2and 9.35 g. m‐2, respectively. The southern barbel becomes sexualy mature at the second year of life for both sexes. The mean absolute fecundity was 9119 ± 322 eggs with mean diameter 1.2 ± 0.2 mm. Spawning of this species, in the study area, occurs in June at mean temperatu

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1987.tb00445.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

Summary9 viruses have been isolated from European eels with stomatopapilloma during 16 years (1968–1984). Isolates (5) from the blood of eels could be identified as IPN‐virus, subtypes Ab, and viruses (4) obtained from tumors were identified asRhabdovirus anguilla, subtype EVX by means of neutralization te

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1987.tb00446.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryA total of 4450 tagged two and three years old salmon smolt were released into the River Drawa. Tagged salmon was caught mainly in central Baltic. Downstream migrating smolt were caught in lower Oder River till mid‐May, and in the Szczecin Firth till the first decade of June. After reaching the sea, the tagged salmon migrated northeastward. They remained most of all in the central Baltic and were mainly caught near Gotland. In autumn of the third year after the release salmon were present on the spawning grounds. The fish attained an average of 58.2 cm and 1892g after the first year of sea life, 78.0 cm and 5329g after the second year, and 98.5cm and 9100g after the third year. Most of the tagged Drawa salmon were caught by Danish (44.7%) and Swedish (25.9%) fisherme

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1987.tb00447.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryAn isolated perfused liver preparation was used to demonstrate the production of Cadmium Binding Protein (CdBP) by rainbow trout liverin vitroduring perfusion with saline media containing cadmium. Synthesis appears to be both time and concentration dependent and the CdBP has the same characteristics as CdBP producedin vivo.

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1987.tb00448.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryThe alternative and classical complement pathways of channel catfish (Ictalurus punctatus), most importantly the classical complement pathway which requires antibody, demonstrated bactericidal activity against two Gram‐negative bacterial fish pathogens,Flexibacter columnarisandVibrio anguillarum.This shows the importance of antibody‐mediated bactericidal immunity in fish by the classical complement pathway in providing protection following immunization or natural infecti

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1987.tb00449.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

SummaryEuropean catfish (Silurus glanis) were tested for their susceptibility to the bacteriumEdwardsiella ictaluri.The LD50ofE. ictaluriwhen injected into European catfish was 5.4 × 106compared to 7.1 times; 104for channel catfish (Ictalurus punctatus).E. ictaluriwas isolated from dead and moribund European catfish and the bacterium was also detected in kidney smears by an indirect fluorescent antibody (FA) technique. The bacterium was not isolated or detected by FA from surviving fish 15 days after injection. No clinical signs ofE. ictaluriinfection were noted in European catfish, but these were prevalent in the channel catfish. These experiments indicate that under experimental conditions European catfish are not as susceptible toE. ictalurias channel catfish

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1987.tb00450.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

ISSN:0175-8659    

DOI:10.1111/j.1439-0426.1987.tb00451.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY