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Increased larval viability with increased spawner age (i.e., maternal effects) have been observed in Atlantic cod (Gadus morhua) and Pacific rockfish (Sebastes spp.) stocks. Analytical results from a Beverton-Holt recruitment model indicate density-independent maternal effects affected the relative stock productivity and fishing rate reference points. We simulated populations based on Pacific cod (Gadus macrocephalus) and Pacific ocean perch (Sebastes alutus) to explore how estimates of reference points [F.sub.msy] and [F.sub.crash] are affected by maternal effects and potential interactions with life-history pattern, recruitment autocorrelation, and exploitation rate. Estimates of [F.sub.msy] and [F.sub.crash] were made from populations with maternal effects using either total larvae (proportional to eggs) or viable larvae (incorporating the maternal effect). Maternal effects have the largest impact upon estimated population productivity at high fishing rates. Estimates of [F.sub.msy] and [F.sub.crash] for cod were also affected by autocorrelated recruitment variability because of their reduced longevity compared with Pacific ocean perch. These results suggest the importance of evaluating the influence of maternal effects on estimated stock productivity on a case-by-case basis, particularly for depleted stocks composed of relatively young spawners. Une viabilite accrue des larves associee a un age plus avance des geniteurs (c.-a-d. effets maternels) a ete observee dans des stocks de morues (Gadus morhua) et de sebastes du Pacifique (Sebastes spp.). Les resultats analytiques d'un modele de recrutement de Beverton-Holt revelent que des effets maternels independants de la densite ont une incidence sur les points de reference associes a la productivite relative du stock et au taux de peche. Nous avons simule des populations basees sur la morue du Pacifique (Gadus macrocephalus) et le sebaste a longue machoire (Sebastes alutus) afin d'explorer l'incidence des effets maternels et d'interactions potentielles avec le type de cycle biologique, l'autocorrelation du recrutement et le taux d'exploitation sur les estimations des points de reference [F.sub.msy] et [F.sub.crash]. Des estimations de [F.sub.msy] et [F.sub.crash] ont ete obtenues pour des populations presentant des effets maternels en utilisant soit les larves totales (proportionnelles aux ceufs) ou les larves viables (en incorporant l'effet maternel). L'incidence des effets maternels sur la productivite estimee de la population est la plus importante a des tauxde peche eleves. Lavariabilite du recrutement autocorrele avaitegalementune incidence sur les estimations de [F.sub.msy]et [F.sub.crash] pour la morue en raison de sa courte longevite comparativement au sebaste a longue machoire. Ces resultats soulignent l'importance d'evaluer au cas par cas l'influence des effets maternels sur la productivite estimee des stocks, particulierement pour les stocks appauvris composes de geniteurs relativement jeunes. [Traduit par la Redaction], Introduction Maternal effects can generally be defined as the nongenetic contribution of females to offspring condition, and in fish this can arise from a number of factors, including female age [...]

Spermatozoon of Atlantic halibut (Hippoglossus hippoglossus (L., 1758)) is uniflagellated, lacks an acrosome, and is differentiated into a head, midpiece, and flagellum. There are two to five mitochondria in the midpiece, as well as proximal and distal centrioles. The flagellum consisted of 9 + 2 microtubules surrounded by plasma membrane, which is extended at the proximal part of the flagellum owing to the presence of vacuoles. After sperm activation in seawater, sperm motility and velocity decreased from 98.4% ± 3.4% and 170.3 ± 8.9 µm x [s.sup.-1] at 15 s after sperm activation to 4.8% ± 4.7% and 9.2 ± 8.9 µm x [s.sup.-1] at 120 s after sperm activation, respectively. ATP content (nmol x [L.sup.-1] ATP per [10.sup.8] spermatozoa) significantly decreased at 60 s after sperm activation (5.9 ± 1.5) compared with at 0 and 30 s after sperm activation (14.9 ± 1.5 and 14.5 ± 1.5, respectively). Beating waves propagated along the full length of the flagellum after sperm activation, whereas waves were restricted to the proximal section during the latter motility period. Wave amplitude significantly decreased at 45 s after sperm activation, but wavelength did not differ. The present study showed associations among sperm morphology, ATP content, flagellar wave parameters, and sperm velocity, which could be used in comparative spermatology. Le spermatozoide du fletan atlantique (Hippoglossus hippoglossus (L., 1758)) est uniflagelle, sans acrosome et differencie en tete, corps median et flagelle. Il y a deux a cinq mitochondries dans le corps median, ainsi que des centrioles proximaux et distaux. Le flagelle consiste en 9 + 2 microtubules entoures d'une membrane plasmatique qui se prolonge dans la partie proximale du flagelle a cause de la presence de vacuoles. Apres l'activation des spermatozoides dans l'eau de mer, la motilite et la vitesse des spermatozoides diminuent respectivement de 98,4 % ± 3,4 % et de 170,3 ± 8,9 µm x [s.sub.-1] a 15 s apres l'activation a 4,8 % ± 4,7 % et 9,2 ± 8,9 µm x [s.sup.-1] a 120 s apres l'activation. Le contenu en ATP (nmol x [L.sub.-1] ATP par 108 spermatozoides) diminue significativement 60 s apres l'activation (5,9 ± 1,5) par comparaison a 0 et 30 s apres l'activation (respectivement 14,9 ± 1,5 et 14,5 ± 1,5). Les ondulations de battement se propagent sur toute la longueur du flagelle apres l'activation, mais sont restreintes a la partie proximale durant la periode de motilite; subsequente. L'amplitude des ondulations diminue significativement a 45 s apres l'activation, mais leur longueur d'onde ne change pas. Notre etude met en lumiere des associations entre la morphologie des spermatozoides, leur contenu en ATP, les variables ondulatoires des flagelles et la vitesse des spermatozoides qui pourraient servir en spermatologie comparee. [Traduit par la Redaction], Introduction Morphology, motility, and seminal plasma composition are considered major elements in the study of comparative fish spermatology (Jamieson 1991; Ishijima et al. 1998; Alavi et al. 2008a). Fish spermatozoa [...]

Phenotypic plasticity occurs when a genotype produces variable phenotypes under different environments; the shapes of such responses are known as norms of reaction. The genetic scale at which reaction norms can be determined is restricted by the experimental unit that can be exposed to variable environments. This has limited their description beyond the family level in higher organisms, thus hindering our understanding of differences in plasticity at the scale of the individual. Using a three-year common-garden experiment, we quantify reaction norms in sperm performance of individual genotypes within different families of Atlantic cod (Gadus morhua). Cod sperm showed phenotypic plasticity in swimming performance across temperatures (3, 6, 11, and 21 °C), but the pattern of the response depended upon how long sperm had been swimming (30, 60, 120, or 180 s), i.e., plasticity in plasticity. Sperm generally swam fastest at intermediate temperatures when first assessed at 30 s after activation. However, a significant genotype x environment interaction was present, indicating inter-individual differences in phenotypic plasticity. To our knowledge this is the first study to describe variable sperm performance across environmental conditions as a reaction norm. The results have potential theoretical, conservation, and aquaculture implications. Resume: Il se produit une plasticite phenotypique lorsqu' un genotype determine des phenotypes qui varient en fonction des differents environnements; les formes de telles reactions sont connues sous le nom de normes de reaction. L'echelle genetique a laquelle les normes de reaction peuvent etre determinees est restreinte par 1'unite experimentale qui peut etre exposee a des environnements variables. Cela a limite leur description au-dela du niveau de la famille chez les organismes superieurs, ce qui a entrave notre comprehension des differences de plasticite a l'echelle des individus. Dans une experience de trois ans en jardin commun, nous avons mesure les normes de reaction dans la performance des spermatozoides de genotypes individuels dans differentes familles de morues franches (Gadus morhua) de l'Atlantique. Les spermatozoides de morues font montre de plasticite phenotypique dans leur performance de nage sur une gamme de temperatures (3, 6, 11, et 21 °C), mais le patron de la reaction depend du temps que le spermatozoide a deja consacre a la nage (30, 60, 120, ou 180 s), c'est donc une plasticite dans la plasticite. Les spermatozoides nagent generalement le plus vite aux temperatures intermediaires lorsqu'ils sont evalues 30 s apres leur activation. Cependant, il existe une interaction significative genotype x environnement, ce qui indique qu'il y a des differences de plasticite phenotypique entre les individus. A notre connaissance, notre etude est la premiere a decrire une performance variable des spermatozoides comme des normes de reaction sur une gamme de conditions du milieu. Nos resultats ont des incidences theoriques potentielles, mais aussi des consequences sur la conservation et l'aquaculture. [Traduit par la Redaction], Introduction The capacity for individuals and populations to respond to spatial and temporal environmental fluctuation is paramount to species persistence. Although populations can evolve through time, individuals cannot undergo genetic [...]