摘要:

The high level of testosterone in the plasma of the femaleRana esculentahas raised a number of questions about the possible role of this hormone in reproductive physiology.

ISSN:0373-4137    

DOI:10.1080/11250007909440271

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

We have described in the male green frog,Rana esculenta, modifications in the total lipids and protein of the testis, fat body, liver and plasma throughout the year. We have considered 1) the fat bodies as the main deposit for lipids in the body because the lipid concentration in this organ constitutes at times more than 50% of the wet tissue, and 2) the liver as the main centre for lipid synthesis. The lipids are released in the plasma and subsequently incorporated in the fat body and in the testis. Annual changes in these parameters have been correlated with gametogenetic activity. We have emphasized the importance of the fat body in controlling testicular activity and the implications of hormones and environmental cues.

ISSN:0373-4137    

DOI:10.1080/11250007909440272

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

D. melanogasterfemales that had been reared from egg to adult on a colored medium preferred to oviposit on the same color when given a choice of four colors in a population cage.

ISSN:0373-4137    

DOI:10.1080/11250007909440273

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

We have described the morphology and life cycle ofApolocystis sp., parasite in the seminal vesicles of the earthwormOctolasium transpadanum(Rosa). The life cycle was investigated by light microscopy but only the mature trophozoite stage by electron microscopy. The trophozoite is spherical, active, rotating quickly. Its ultrastructure conforms broadly to that of other gregarines. The pellicle is composed of 3 parallel unit membranes and forms a number of epicitary folds arranged as a labyrinth. These folds are not stable structures and may appear anywhere on the trophozoite surface. Micropores concerned with feeding, are randomly distributed on the pellicle. Many haptonemata start from the surface and pass through the barrier of the amoebocytes that always surround the trophozoite. A precise limit between the ectoplasm and the endoplasm does not exist; mitochondria, dense bodies and other inclusions are found within the top of the folds. Mitochondria are located superficially. Microtubules enter into the haptonemata and are found beneath the pellicle where they constitute a cytoskeleton. The cytoplasm has a poorly developed reticulum, but is filled with free ribosomes, with typical paraglycogen granules and numerous other inclusions. The nucleus has a homogeneous matrix and a compact spherical nucleolus. The role of the fine morphology in the taxonomy of Monocistidae gregarines is discussed.

ISSN:0373-4137    

DOI:10.1080/11250007909440274

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

In the present research we subjected four experimental series of mice to aggression tests. In the first series (A) we compared male mice kept in isolation with random chosen male mice raised socially. In series B we set dominant males (selected after social combat) against mice kept in isolation. In series C we set submissive individuals (defeated in social combat) against isolated mice. In the last series (D) we confronted dominant male mice with unknown submissive mice. Outcomes of the fights, analysis of encounters without fighting and analysis of body weight in series A, B and C show that isolation confers certain behavioural characteristics similar to those of social dominants as far as the aggressiveness and the tendency to attack another male are. concerned. However, the outcome of fights between isolated and dominant mice (dominants obtained more victories) and the results of encounters in series C and D show clearly that isolated mice are less aggressive than dominants. Our data raise the problem as to whether the aggressive behaviour induced in isolation should be considered of pathological origin, since dominants (not socially deprived) are more aggressive towards another male even if the latter happens to be a submissive individual. One important conclusion emerges from our data: with regard to the motivation for aggressive behaviour, the “greater” aggressiveness of mice kept in isolation has been used to support Lorenz's theory about the urge to attack. Our findings are clearly in contrast with this theory and with the postulates of the psychological-hydraulic pattern proposed by Lorenz (1950) to explain the causes of aggressive behaviour.

ISSN:0373-4137    

DOI:10.1080/11250007909440275

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

In the toadBufo viridis, the electrophoretic pattern of the hemoglobin changes during development. The various stages from larva to adult have been observed and reported in a standardized diagram.

ISSN:0373-4137    

DOI:10.1080/11250007909440276

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The influence of estradiol benzoate (EB) on erythropoiesis was evaluated in the cat-fish.

ISSN:0373-4137    

DOI:10.1080/11250007909440277

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The aggressive behaviour of 26 male mice isolated for 21 days was compared with that of 26 males which were dominant in a pair for the same period.

ISSN:0373-4137    

DOI:10.1080/11250007909440278

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Megoura victuelarvae topically treated with n-butanol die before moulting; n-butanol has a low toxicity for adults. The integument of the treated larvae reveals the absence of a cleavage between the old cuticle and the new one when it is completely formed. Histology of the cerebral and retrocerebral organs shows degeneration of the corpus allatum as observed after treatment with juvenile hormone mimics.

ISSN:0373-4137    

DOI:10.1080/11250007909440279

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Euglena graciliswas exposed to cytochalasins B and D, dissolved in dimethylsulfoxide (DMSO).

ISSN:0373-4137    

DOI:10.1080/11250007909440280

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor