caa a22 4500 386400423 CHVBK 20180307112156.0 cr unu---uuuuu 161130e198906 xx s 000 0 eng 10.1017/S0031182000061588 doi S0031182000061588 pii (NATIONALLICENCE)cambridge-10.1017/S0031182000061588 Differences in numbers and inequalities in mass and fecundity during the egg-producing period for Raphidascaris acus (Nematoda: Anisakidae) [Elektronische Daten] Maturity, mass and sex were determined for individual Raphidascaris acus from northern pike, Esox lucius from Dauphin Lake, Manitoba. Length, width and total fecundity of female worms; seasonal changes in worm numbers, growth and maturity; and inequalities in mass and fecundity were quantified for 8 sample periods between April and September. Recruitment of R. acus is most rapid in early spring and continues throughout summer. An accumulation of larvae over winter leads to a peak in the number of gravid worms in spring, while increased feeding by post-spawning pike on yellow perch, Perca fluviatilis, leads to lower levels of gravid worms throughout summer and early autumn. Gravid worms found in spring versus summer were similar with respect to all measured variables and do not appear to be from genetically distinct populations. The strength of the correlation between fecundity and mass for worms was variable between pike and between sample periods, and only weakly correlated when the data were pooled. Much of this variation could be attributed to continued growth of gravid worms after maturation. Worms found in June were smaller, less fecund and less variable and inequalities in mass and fecundity measured using Gini coefficients (GCs) and Lorenz curves (LCs) were most similar at this time. For all other sample periods inequality in fecundity was greater than the corresponding value for mass. Similarity between GCs based on mass and fecundity was maximum when the coefficient of variation (C.V.) for mass was greater than the corresponding C.V. for fecundity. These observations suggest that one must be cautious when applying GCs and LCs to the analysis of parasite populations. Copyright © Cambridge University Press 1989 Raphidascaris acus nationallicence fecundity nationallicence worm numbers nationallicence mass nationallicence seasonal variations nationallicence egg production nationallicence Szalai A. J. Department of Zoology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 Dick T. A. Department of Zoology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 Parasitology Cambridge University Press 98/3(1989-06), 489-495 0031-1820 98:3<489 1989 98 PAR https://doi.org/10.1017/S0031182000061588 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0031182000061588 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Szalai A. J. Department of Zoology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 NATIONALLICENCE 700 1- Dick T. A. Department of Zoology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 NATIONALLICENCE 773 0- Parasitology Cambridge University Press 98/3(1989-06), 489-495 0031-1820 98:3<489 1989 98 PAR CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge