摘要:

Trimethylamine oxide was found in the muscle press juice of all salt water fish examined and in the anadromous fishPomolobus pseudoharengustaken from the sea. Traces were found inAnguillataken from salt water, but none inAnguillafrom fresh water.

ISSN:0706-652X    

DOI:10.1139/f38-021

出版商:NRC Research Press    

年代:1939

数据来源: NRC

摘要:

Pink salmon fry were marked by the removal of certain fins to ensure later identification as adults. This procedure does not affect the growth or the feeding reactions of the fish. Three experiments were conducted on natural runs at McClinton creek, Masset inlet, B.C. On the basis of the most significant one of these it is concluded that the majority of the fish return to spawn in the stream in which they were hatched. Isolated individuals, in numbers not economically significant, may wander to a distance of 400 miles (645 kilometres). In the case of fry resulting from transplantation experiments from Tlell river, east coast of Graham island, to McClinton creek, there appears no consistent behaviour in regard to "homing". For fry, hatchery-raised and pond-reared, from Vedder river, Swelter creek eggs, no return to the parent stream was reported. All pink salmon mature in the autumn of their second year. Certain incidental checks in growth have been discovered on scales which should not be interpreted as representing a winter.

ISSN:0706-652X    

DOI:10.1139/f38-022

出版商:NRC Research Press    

年代:1939

数据来源: NRC

摘要:

In fish muscle press juice simulating the surface and the interior of muscle, there is an aerobic environment in the surface layer and an anaerobic environment in the body of the liquid. The Eh potential of the former is about 0.3 volts and of the latter from −0.5 to −0.10 volt.It is found that the bacterial population proliferating at 2 °C. is chieflyAchromobacter, which can be divided into two groups, obligate aerobes and facultative anaerobes. Only the latter group, which is capable of growth in the interior or surface, is responsible for the reduction of trimethylamine oxide with the evolution of trimethylamine. Since the initial total count is made up of a large number of obligate aerobes or non-oxide reducers it is obvious that the total bacterial population cannot be related to trimethylamine production. The appearance of this base therefore may be taken to indicate a bacterial population which is in excess of that responsible for its production.Molecular oxygen at surface exercises a trimethylamine oxide sparing effect. In practice, however, this effect is not significant from the point of view of the freshness test in the sense of Beatty and Gibbons.

ISSN:0706-652X    

DOI:10.1139/f38-023

出版商:NRC Research Press    

年代:1939

数据来源: NRC

摘要:

A general equation involving the reduction of trimethylamine oxide byAchromobacteris derived and tested, and is AH2 + (CH3)3NO → A + (CH3)3N + H2O, where AH2is the hydrogen donator and A the oxidized substrate. The reduction of trimethylamine oxide as hydrogen acceptor with the evolution of trimethylamine is a linear function of time in the presence of cell suspensions and single hydrogen donators including glucose, glycogen, lactate, and pyruvate. All strains ofAchromobacterare not able to reduce the oxide, although they may contain the same dehydrogenases as revealed by employing the methylene blue technique. Small concentrations of hydrogen acceptors such as nitrate and methylene blue inhibit the reduction of the oxide. Since fumarate is not inhibitive and supports anaerobic growth there is evidence of a preferential activation of hydrogen acceptors.

ISSN:0706-652X    

DOI:10.1139/f38-024

出版商:NRC Research Press    

年代:1939

数据来源: NRC

摘要:

Records of occurrence of nine different species out of thirteen known in the region, includingBoreomysis tridens, not known previously.

ISSN:0706-652X    

DOI:10.1139/f38-025

出版商:NRC Research Press    

年代:1939

数据来源: NRC

摘要:

Oysters spawn when ripe, with rising temperatures that may or may not reach 20 °C. and at times not determined by lunar cycles. The growth of the larva to the ultimate size, height 365 μ, at temperatures of 19, 20 and 21 °C., requires 30, 26 and 24 days respectively. The growth curves developed, not sigmoidal in shape, have been used to predict spatfall maxima.

ISSN:0706-652X    

DOI:10.1139/f38-026

出版商:NRC Research Press    

年代:1939

数据来源: NRC

摘要:

InSalvelinus fontinalistwo scale papillae develop on the lateral line over each myotome. They appear as far back as the adipose fin and independently on the dorsal line anterior to the adipose fin. The scale pattern develops by extensions obliquely forward from the primary papillae. Development is more rapid in the posterior region. Chief variations are bifurcation of rows and extension of rows posteriorly.

ISSN:0706-652X    

DOI:10.1139/f38-027

出版商:NRC Research Press    

年代:1939

数据来源: NRC

摘要:

not available

ISSN:0706-652X    

DOI:10.1139/f38-020

出版商:NRC Research Press    

年代:1939

数据来源: NRC