Browsing by Issue Date, starting with "2025-05-01"
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- Melatonin rhythms beyond the pineal organ: gene expression of receptors and biosynthesis enzymes in wild and F1 Senegalese solePublication . Félix de Azeredo Pinto e Melo, Francisca; Oliveira, Catarina; Martín, Ignacio; Manchado, Manuel; Sánchez-Vázquez, Francisco J.; Vera, Luisa M.; Cabrita, ElsaFish gonadal melatonin production is still unexplored and could contribute to a better understanding of its role in reproduction control, especially for species with reproductive impairments. This study aimed to comprehend if Senegalese sole testes are an extra-pineal production site of melatonin and if it has seasonal and daily variations. Wild and F1 broodstocks were sampled in the breeding season (BS) and out of the reproductive season (OS), at mid-light (ML) and mid-dark (MD) daytimes. Blood plasma melatonin concentration was determined by radioimmunoassay (RIA). The expression of genes involved in melatonin biosynthesis (tph1a, tph2, hiomt1, aanat1a, aanat1b, and aanat2) and melatonin receptors (mel1, mel1c, and mel2) was evaluated in the brain, eye, and testis by quantitative real-time PCR (qPCR). Plasma melatonin concentration in wild sole displayed day/night differences in both seasons (average ML: 36 +/- 22 pg/mL, MD: 108 +/- 63 pg/mL), whereas differences in the F1 broodstock were only found OS (ML: 100 +/- 54 pg/mL, MD: 187 +/- 88 pg/mL). Gene expression of mel1 and mel2 receptors, and tph1a, aanat1a, aanat2, and hiomt1 enzymes was detected and quantified in the fish testes. Moreover, daily and seasonal fluctuations in the expression of those genes were found in all tissues and broodstock groups. However, the F1 group showed distinct gene expression patterns compared to the wild type, suggesting a disruption in the circadian system. This study revealed that Senegalese sole testes are a melatonin production site and, at the same time, suggested a dysregulation in the hypothalamus-pituitary-gonad (HPG) axis of F1 males.
- High-density SNP panel provides little evidence for population structure in European sea bass (Dicentrarchus labrax) in waters surrounding the UKPublication . Taylor, Martin I.; Lamb, Philip D.; Coscia, Ilaria; Murray, David S.; Brown, Mary; Cameron, Tom C.; Davison, Phil I.; Freeman, Howard A.; Georgiou, Katerina; Grati, Fabio; Haugen, Thrond; Karachle, Paraskevi K.; Kennedy, Richard; Lanssens, Thomas; Lincoln, Harriet; Martinho, Filipe; McCarthy, Ian; Petroutsos, Spyros-Iasonas; Pita, Pablo; Pontes, João; Baucells, Marta P.; Rangel, Mafalda; Roche, William; Sbragaglia, Valerio; Sturrock, Anna M; Taylor, Michelle L; Wogerbauer, Ciara; Veiga, Pedro; Verver, Sieto; Weltersbach, Marc Simon; Hyder, Kieran; Stewart W GrantThe European sea bass (Dicentrarchus labrax) is a commercially and recreationally important fish widely, distributed across the Northeast Atlantic Ocean and Mediterranean Sea. Two distinct lineages that represent the Atlantic and Mediterranean regions have been previously identified, with a hybrid zone close to the Almeria-Oran front. The presence of fine-scale population structure within the Northeast Atlantic region is less clear. Here, we investigated population structure in adult samples obtained from the northern part of the Atlantic range surrounding the UK, Ireland, Belgium, Germany, France, the Netherlands, and Norway, along with outgroups from Portugal and the Mediterranean, using a panel of 41 K single nucleotide polymorphism markers. Population structure among Northeast Atlantic Ocean samples was weak in both spawning-(FST = 0.00022) and feeding-(FST = 0.00032) season data sets, with small pairwise FST values between sample pairs. However, average FST was larger between spawning samples than between feeding samples, with a pattern of isolation-by-distance among the spawning samples, but not the feeding samples, suggesting some biologically meaningful population structure. The largest pairwise FST values at both International Council for the Exploration of the Sea (ICES) rectangle and division scales involved a sample from the west of Ireland. We found no evidence of a gradient in "Mediterranean" ancestry among samples collected around the UK in our data set or in a reanalysis of a published data set where such a pattern had been previously identified. In summary, there was no evidence that sea bass in different ICES divisions within the Northeast Atlantic Ocean represents genetically separate populations. Further work is required to reconcile evidence from tagging and modelling studies that suggest the potential for demographic independence with the genetic data.
- Design optimisation of five pilot-scale two-stage vertical flow-constructed wetlands for piggery wastewater treatmentPublication . N., Karan; Gogoi, Jayanta Kumar; Ganguly, Anasuya; Brito, António Guerreiro de; Cordovil, Claudia S. C. Marques dos Santos; Correa, Diego; Gouveia, Luisa; Mutnuri, SrikanthWith growing pig farming, sustainable piggery wastewater treatment methods are essential for environmental protection. This study evaluated five pilot-scale two-stage vertical flow-constructed wetlands (VFCWs) with varying configurations of aeration, plantation, and saturation zones. Three VFCW configurations (1VFCW, 2VFCW, and 3VFCW) were unsaturated, while 4VFCW and 5VFCW were saturated in the second stage (up to 60 and 90 cm, respectively). The 5VFCW featured a stacked configuration with no space between its two stages. Passive aeration was selectively applied in 2VFCW, 3VFCW, 4VFCW, and 5VFCW, while plants were present in most configurations except the control. Saturated 4VFCW achieved the highest removal efficiency for TN (77.03 + 16.24%) and NO3 (46.06 + 45.96%), while the stacked 5VFCW showed the highest removal for chemical oxygen demand (COD) (94.17 + 4.85%) and total ammoniacal nitrogen (TOC) (86.35 + 6.78%). Unsaturated 1VFCW excelled in TAN removal (98.89 + 0.33%), and the control system (C) showed the highest removal efficiency for PO4 3 (90.38 + 6.52%) and TOC (87.52 + 9.83%). Overall, 4VFCW emerged as the most balanced and effective system, supported by an optimal combination of aerobic and anaerobic conditions that facilitated sequential nitrification and denitrification, along with an extended hydraulic retention time due to saturation.