Biology subjects

Goardon, L.

Publications and source records attributed to Goardon, L..

3 recordsLinked to original sources

bioRxiv2023

From the third to the seventh generation of selection for muscle fat content in rainbow trout: Consequences for flesh quality

Muscle lipid content was shown to affect many quality features in salmonids in both raw and processed fillets. The objective of the present work was to assess the consequences of 7 generations of divergent selection for muscle adiposity on some rainbow trout flesh quality and muscle parameters. Fish from Lean (L) and Fat (F) lines had a similar body weight but L fish were longer and had consequently lower condition factor values. Carcass yield was not affected by selective breeding, but L fish had lower hepato- and gonado-somatic indexes, a bigger head, and lower fillet yield than F fish. A difference of more than 15 points in mean fat-meter(R) values (genetic selection criteria) was measured between the two lines. Mean muscle lipid content was 5.0{+/-}1.0% for L line vs 13.5{+/-}2.2% for F line. An absolute difference of more than 6% was measured in fillet dry matter content between the two lines, for raw, cooked, and smoked fillets. Raw fillets from F fish were lighter (L*>) and more colorful (a* and b*>), but softer than those from the L line. Quality parameters of cooked fillets were very similar between the two lines, whereas smoked fillets exhibited, between the two lines, similar differences than raw fillets. A large difference in white muscle fiber size was observed, fish from F line having higher fiber mean diameter, a lower proportion of small fibers, and a higher proportion of large fibers. Sex effects were observed on these immature fish, on classically sex-related traits (GSI and head development), but also on muscle fiber size. Moreover, these effects were more marked in F line. Correlation analysis showed that raw fillet color was positively related to muscle adiposity whereas mechanical resistance was negatively related. Raw fillet mechanical resistance was also negatively correlated to white muscle fiber size. Moreover, smoked fillet quality parameters were correlated to raw fillet ones. The relationships between muscle adiposity, but also muscle cellularity, and fillet quality were discussed. HighlightsO_LI7 generations of adiposity divergent selection affect raw and smoked fillet quality. C_LIO_LISelective breeding led to a noteworthy response in white muscle cellularity. C_LIO_LISome differences between male and female was measured in immature pan-size trout. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=195 SRC="FIGDIR/small/569019v1_ufig1.gif" ALT="Figure 1"> View larger version (37K): org.highwire.dtl.DTLVardef@10b25f6org.highwire.dtl.DTLVardef@e9402aorg.highwire.dtl.DTLVardef@173b1f9org.highwire.dtl.DTLVardef@a9898b_HPS_FORMAT_FIGEXP M_FIG C_FIG

physiology↗

bioRxiv2023

Links between behaviour and resistances to acute hyperthermia and hypoxia using rainbow trout isogenic lines

In the context of adaptation to climate change, acute hyperthermia and hypoxia resistance are traits of growing interest in aquaculture. The feasibility of genetic improvement of these resistance traits through selection has been demonstrated in rainbow trout (Oncorhynchus mykiss). The present paper aims to test whether behaviour may be associated with acute hyperthermia and hypoxia resistance to better characterize these resistance phenotypes. For this, six rainbow trout isogenic lines were phenotyped for behaviour variables and for acute hyperthermia and hypoxia resistance, using different individuals for each phenotype. The behaviour variables of the fish were phenotyped using an individual test in a new environment. The experimental design used 150 fish phenotyped per isogenic line for each resistance trait and 18 fish per isogenic line for behavioural traits, distributed in triplicates. Relations between acute hyperthermia and hypoxia resistance phenotypes and behaviour phenotypes were tested at the level of isogenic lines. Significant differences in behaviour between isogenic lines were found, with some behaviour variables being highly associated with hypoxia resistance and moderately associated with acute hyperthermia resistance. Travelling distance, frequency of change between a risky and a safe zone of the tank and the percentage of time in movement in the behaviour test were strongly positively associated with acute hypoxia resistance. Travelling distance and frequency of change between a risky and a safe zone of the tank in the behaviour test were slightly negatively associated with acute hyperthermia resistance. This previously unstudied link between behaviour and resistance phenotypes also suggests that some behaviour variables could be used as predictors for acute hyperthermia and hypoxia resistance in fish. This result could lead to more ethical acute hyperthermia and hypoxia resistance phenotyping protocols, as the current protocols in use are classified as severe by French ethics committees.

animal behavior and cognition↗

bioRxiv2018

A novel emotional and cognitive approach to welfare phenotyping in rainbow trout exposed to poor water quality

Recent scientific evidence for fish sentience has stressed the need for novel sentience-based detection tools of fish welfare impairment in commercial farms. In order to mimic a well-characterised stress situation, rainbow trout (Oncorhynchus mykiss) were exposed to poor water quality (hypoxia combined with high ammonia level) for three weeks (stressed group, S) and compared to a non-stressed control group (NS). After a return to water quality standard, emotional responses were assessed in fish subjected to two potentially threatening situations: (i) social isolation in a novel environment and (ii) human presence. In addition, we used an appetitive-conditioning paradigm to determine whether previous chronic deterioration of water quality disturbs cognitive abilities in fish. Spontaneous behaviour in the tanks was also recorded during the environmental challenge as a reference for fish activity. We observed that in S fish, plasma cortisol levels were increased before and after social isolation in a novel environment compared to the plasma cortisol levels in the NS group, despite the absence of a behavioural difference between the two groups. Under deteriorated water quality, fish locomotor activity was globally reduced and this reduction was correlated to increased shoaling behaviour. Farmers can use these first behavioural modifications as a sentinel detector for fish welfare impairment. More importantly, we demonstrated that reactivity to a human presence in a home-environment and food-anticipatory behaviour were both inhibited in the S group. We consider that these two sentience-based tests are highly relevant for fish welfare assessment at the group level and are easy to use in the aquaculture industry.

animal behavior and cognition↗