Metataxonomic and lipidomic fertility markers and modulators in farmed pikeperch (Sander lucioperca) females

Authors: Jovanka Lukić1,2, Jelena Stanivuk1, Zsuzsanna J. Sándor1, András Bognár3, Uroš Ljubobratović1, Norbert Vass1, Georgina Lea Fazekas1, Zoltan Nagy1, Dorottya Lilla Fazekas1, Vera Gomes4, Anita Annamária Szűcs1, Tamás Gergely Molnár3, Gergő Gyalog1, Ana Margarida Amaral4

Affiliations:

1 - Hungarian University of Agriculture and Life Sciences, Institute of Aquaculture and Environmental Safety, Research Center for Fisheries and Aquaculture (MATE AKI HAKI), Hungary

2 - author’s former affiliation: Institute of Molecular Genetics and Genetic Engineering, University of Belgrade (IMGGE), Republic of Serbia

3 - Hungarian University of Agriculture and Life Sciences, Institute of Aquaculture and Environmental Safety, Department of Applied Fish Biology, MATE AKI, Hungary

4 - Centre of Marine Sciences (CCMAR), Portugal

Abstract:

The aim of this study was to identify biological signals within the pikeperch females’ gut metataxonome and egg lipidome that could predict fertility traits and support intervention strategies. Research was conducted using farmed naïve spawners maintained under common husbandry conditions throughout vitellogenesis. Fecal samples were collected during early vitellogenesis for 16S amplicon sequencing, while maternal plasma and stripped eggs were collected following hormonal induction for cortisol and lipid analysis, respectively. Predictive modelling, causal-effect analysis, and covariate-adjusted ridge regression were employed to assess the relationships between the above features and fertility indicators. The study revealed that metabolic pathways associated with bacterial starvation and/or stress, may act as key negative regulators of egg production. This was coupled with negative associations of the same trait with Cetobacterium and Romboutsia, with a similar pattern observed for docosadienoic acid (22:2n-6). Embryo survival was positively associated with 18-carbon chain ω3 fatty acids, as well as metataxonomic features, including Aeromonas, Anaerosalibacter, Cyanobium, Streptococcus, and members of the Beijerinckiaceae family. Similarly, docosadienoic acid, and nervonic acid (21:1n-9), were positively associated with embryo survival, whereas no association was observed for highly unsaturated fatty acids. Classification models identified egg docosadienoic, pentadecanoic (15:0) and elaidic acid (18:1n-9T), together with gut fatty acid salvage, heme b synthesis, and reductive Stickland reaction, as the top variables contributing to model predictions. Further validation in larger cohorts and under diverse husbandry conditions, combined with the evaluation of less invasive sampling matrices, is recommended to support the development of dietary intervention strategies and broodstock selection tools.