ISSN:
1432-1793
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
Notizen:
Abstract The present study on chemotaxis activity was conducted between May 1989 and March 1990. In order to establish a chemotaxis index, with special reference to a repellence index of food for black abalone Haliotis discus, a logistic curve y=g/{1+ exp [-r(j-a)]}, where g, r and a are constants, was applied to time-courses of abalone responses to fresh and spoiled algal extracts. The time-courses were respresented by the number of individuals (y i) displaying three behaviors (entering. leaving and remaining in a test compartment with algal sample) over time (j=1 to 10, 2-min intervals). Repellence and attraction specimens were prepared from a homogenate of green laver Ulva pertusa allowed to spoil for 2, 4 and 6 d at 40°C, and from fresh homogenate, respectively. Of 32 time-courses (estimated according to a method whereby the observed number was weighted by j for each behavior, involving 30 individuals), 32 “entered”, 19 “left” and 19 “remained” time-courses fitted the curve at the 0.10 level, as determined by a chi-square test. A general evaluation of repellence and attraction, determined by observable behavior, agreed well with the difference in a between the dummy (control) and specimen curves, and with the ratio of a in the dummy curve to a in the specimen curve, for logistic curves fitted to the “entred” time-course. The difference was 〉0 and the ratio was 〉1 in the repellence index, and 〈0 or 〈1 respectively in the attraction index. The validity of the indexes was ascertained using food specimens prepared from three kinds of algae.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00356283
Permalink
