Prenatal stress from trawl capture affects mothers and neonates:a case study using the southern fiddler ray (<i>Trygonorrhina dumerilii</i>)

Assessing fishing effects on chondrichthyan populations has predominantly focused on 15 quantifying mortality rates. Consequently, sub-lethal effects of capture stress on the 16 reproductive capacity of chondrichthyans are largely unknown. We investigated the 17 reproductive consequences of capture on pregnant southern fiddler rays (Trygonorrhina 18 dumerilii) collected from Swan Bay, Australia, in response to laboratory-simulated trawl 19 capture (8 h) followed immediately by air exposure (30 min). Immediately prior to, and for 20 up to 28 days post trawling, all females were measured for body mass (BM), sex steroid 21 concentrations (17-β estradiol, progesterone, testosterone) and granulocyte to lymphocyte 22 (G:L) ratio. At parturition, neonates were measured for total length (TL), BM and G:L ratio. 23 Trawling reduced maternal BM and elevated the G:L ratio for up to 28 days. Trawling did not 24 significantly affect any sex steroid concentrations relative to controls. Neonates from trawled 25 mothers were significantly lower in BM and TL than control animals, and had an elevated 26 G:L ratio. Our results show that capture of pregnant T. dumerilii can influence their 27 reproductive potential and the fitness of neonates. We suggest other viviparous species are 28 likely to be similarly affected. Sub-lethal effects of capture, particularly on reproduction, 29 require further study, particularly reproduction, to improve fisheries management and 30 conservation of chondrichthyan species.Fil: Guida, L.. Monash University; AustraliaFil: Awruch, Cynthia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina. University of Tasmania; AustraliaFil: Waker, T.. Monash University; AustraliaFil: Reina. R.. Monash University; Australi

Liver Transcriptome Changes in Zebrafish during Acclimation to Transport-Associated Stress

Liver plays a key role during the stress acclimation, and liver transcriptome analysis of shipped zebrafish could reveal the molecular adjustments that occur in the organ. Transcriptional changes in liver were analyzed with a 44 K oligo array using total RNA from fish prior to transport and during a mock transport process - immediately after packing (0 h), at 48 and 72 h. Large numbers of genes related to a variety of biological processes and pathways were regulated, mainly during transport (at 48/72 h). Immediately after packing, transcripts of genes related to both gluconeogenesis and glycolysis were induced. During transport, induction of gluconeogenesis-linked genes and reduction of glycolysis-related genes may be supporting the increase in blood glucose levels. Inhibition of genes involved in fatty acid beta-oxidation may be pointing to the poor ability of fish to utilize energy from fatty acids, under transport conditions. Genes involved in some of the mechanisms that regulate body ammonia were also affected. Even though genes associated with certain transaminases were inhibited in liver, sustained glutamate deamination may have led to high ammonia accumulation in liver/body. Enhanced levels of gene transcripts in ubiquitination and MAPK signalling cascade and reduced levels of gene transcripts related to ROS generation via peroxisomal enzymes as well as xenobiotic metabolism may be signifying the importance of such cellular and tissue responses to maintain homeostasis. Furthermore, transcripts connected with stress and thyroid hormones were also regulated. Moreover, suppression of genes related to specific immune components may be denoting the deleterious impact of transport on fish health. Thus, this study has revealed the complex molecular -adjustments that occur in zebrafish when they are transported