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  • Evaluation of superworm (Zophobas morio) larvae meal as a fish meal substitute in juvenile stellate sturgeon (Acipenser stellatus) diets
    Publication . Lebria, Arash; Langroudi, Hadi Ershad; Pajand, Zabih Ollah; Sajjadi, Mirmasoud; Abdollahpour, Hamed
    This study aimed to evaluate the effects of dietary inclusion of superworm (Zophobas morio) larvae meal (SWM) on growth performance, hematological parameters, blood biochemical parameters, proteolytic enzyme activity, and body composition in juvenile stellate sturgeon (Acipenser stellatus). A total of 120 juvenile fish (initial body weight: 28.08 ± 0.13 g) were randomly assigned to four dietary treatments in triplicate groups. Experimental diets were formulated to replace 0% (control), 10% (SWM10), 20% (SWM20), and 30% (SWM30) of fish meal with SWM, maintaining isonitrogenous (45.27% protein) and isoenergetic (19.50 MJ/kg) profiles. Fish were hand-fed to apparent satiation three times daily over an 8-week period. Growth performance data indicated that up to 10% SWM inclusion did not significantly affect final weight, weight gain, or condition factor compared to the control (p > 0.05). However, 20% and 30% inclusion levels resulted in significantly reduced growth performance (p < 0.05). Hematological analysis showed that WBC counts were significantly higher in all SWM-fed groups (16.2–19.3 ×10 ³/mm³) compared to the control (13.9 ×10 ³/mm³), with neutrophil percentages also elevated (16.3–17.2% vs. 13.7% in the control) (p < 0.05). No significant differences were observed in RBC count, hemoglobin, hematocrit, MCV, MCH, or MCHC (p > 0.05). Biochemical results showed that triglyceride levels were significantly elevated in the SWM30 group (p < 0.05), while cholesterol levels were significantly lower compared to the control (p < 0.05). Serum glucose level remained unaffected across treatments (p > 0.05). Proteolytic enzyme analysis indicated a significant reduction in trypsin activity in fish fed the SWM30 diet (p < 0.05). Whole-body composition analysis revealed that increasing SWM inclusion significantly decreased carcass protein, moisture, and ash contents, while lipid content increased, with the highest fat level observed in the SWM30 group (p < 0.05). Overall, the findings suggest that superworm larvae meals can be included in the diet of juvenile stellate sturgeon at levels up to 10% fishmeal replacement without adverse effects on growth, hematological parameters, blood biochemistry, or proteolytic enzyme activity.
    2026-07Artigo científico Acesso aberto Ver mais
  • The palynology of the upper triassic-lower jurassic in the Algarve and Lusitanian basins, Portugal
    Publication . Vilas-Boas, Margarida; Cirilli, Simonetta; Pereira, Zélia; Duarte, Luís Vítor; Fernandes, Paulo
    High-resolution palynological analyses from the Algarve and Lusitanian basins (Portugal) provide a refined biostratigraphical framework and palaeoenvironmental reconstruction for the Late Triassic–Early Jurassic transition. In the Algarve Basin, three new palynozones (AT, SC, and CP) characterise the Silves Group from the early Carnian to early Hettangian, documenting the first Iberian occurrence of Tulesporites briscoensis and precisely delineating the Triassic–Jurassic Boundary (TJB). In the Lusitanian Basin, three palynozones (CG, IK, and Pm) constrain the Conraria and Pereiros formations to the Norian–Hettangian, with the TJB located at the base of the Pereiros Formation. Palaeoenvironmental reconstructions reveal distinct basin-specific evolutions. The Algarve Basin records an early transition from fluvial (Silves Sandstones) to marginal-marine (lagoonal and pond) settings, evidenced by abundant upper Carnian algal elements and reworked Neoproterozoic algae. Conversely, the Lusitanian Basin reflects a Norian-Hettangian marginal-marine, river-dominated setting, with microforaminiferal linings at the base of the Pereiros Formation marking the earliest marine transgression in the Lusitanian Basin. Quantitatively, both basins show a persistent dominance of xerophytic taxa, indicating a shift toward warmer, seasonally dry conditions across the TJB. Malformed sporomorphs in both records suggest environmental stress potentially linked to Central Atlantic Magmatic Province (CAMP) activity. Comparative analysis reveals that sedimentation initiated earlier in the Algarve (early Carnian) than in the Lusitanian Basin (Norian), suggesting diachronous development during Pangaea breakup. The assemblages show strong affinities with the Onslow Microflora, highlighting the Portuguese margin as a key archive for western Tethyan floral and climatic evolution.
    2026-07Artigo científico Acesso aberto Ver mais