This research examined the efficacy of substituting commercial fish meal (CFM) with Pterygoplichthys pardalis meal (PPM) in Hoplobatrachus chinensis diets, with and without Euphorbia hirta extract (EHE) supplementation. The study utilized six dietary treatments: a control diet (0% PPM, no EHE) and five experimental diets with varying PPM levels (0%+, 25%+, 50%+, 75%+, and 100%+), each fortified with 300 mg/kg EHE. The experiment spanned 90 days. The analysis revealed that PPM exhibited superior amino acid profiles compared to CFM, both in quality and quantity, while CFM demonstrated higher fatty acid content. The growth metrics showed a significant decline only in the group receiving 100% PPM replacement with EHE supplementation. Most organosomatic indices remained consistent across the treatments, with the exception of intraperitoneal fat, which decreased in all EHE-supplemented groups. Blood parameters, including white blood cells, red blood cells, and hematocrit, along with serum proteins (total protein, globulin, and albumin), displayed an upward trend in all EHE-supplemented groups. The 50%+ and 75%+ PPM replacement groups exhibited significantly elevated serum glucose levels (p < 0.05). Liver enzymes (alanine transaminase and aspartate transaminase) showed no significant variations among the treatments. The results indicate that PPM can serve as an effective replacement for up to 75% of CFM in H. chinensis feed, without compromising their growth performance. Moreover, supplementing with EHE helps to enhance essential biochemical indices in the body, without adversely affecting liver function. This investigation offers valuable perspectives on the development of sustainable aquaculture feed and the potential application of invasive fish species in aquatic animal nutrition.

This study aimed to assess the viability of replacing rice bran with spent coffee grounds (SCG) in the diets of Oreochromis niloticus (average body weight, 48.8 ± 0.42 g). The fish were randomly allocated into four sets of three groups each and placed in net cages (1 m × 2 m × 0.5 m) at a density of 30 fish per cage. They were fed diets with four different replacement levels: 0%, 5%, 10%, and 15% of SCG over a period of 90 days. Growth and serum biochemical indices were monitored three times at 30, 60, and 90 days. During the experiment, there were no significant differences (P > 0.05) observed in growth indices, including weight gain (WG), daily WG, specific growth rate, feed conversion rate, protein efficiency ratio, and survival rate among the groups at 30, 60, and 90 days. Serum biochemical indices, such as aspartate aminotransferase and alanine aminotransferase, showed a similar trend with significant differences observed only on day 30, while the lowest and highest levels were found in the control and 15% SCG replacement groups, respectively. For total cholesterol, a significantly different result was found only on day 30. However, these differences were not sustained in subsequent assessments. Conversely, serum glucose, total protein, albumin, and globulin remained unaffected by SCG replacement throughout the experiment. The findings indicate that replacing rice bran with up to 15% SCG did not adversely impact the growth performance or key serum biochemical indices of Nile tilapia. To the researchers’ knowledge, these findings are the first in the field to substitute SCG for rice bran, opening a new avenue for further research.

This study investigates the biochemical and physiological responses of the economically important fish Barbonymus gonionotus to acute temperature fluctuations. Focusing on malondialdehyde (MDA) levels in serum and visceral organs, serum biochemical indices, hematological parameters, cortisol levels, and operculum movement, this research assessed the impacts of thermal stress. Experimental conditions involved two thermal regimes: heat shock at 25–29 °C and 25–37 °C; as well as cold shock at 25–21 °C and 25–13 °C sustained over 24 (D1), 48 (D2), and 72 (D3) h. Serum MDA levels increased significantly. Notably, MDA in the gills, brain, and liver fluctuated under cold stress, particularly at 13 °C. Serum parameters showed significant alterations except for AST, total protein, and cholesterol, which remained unaffected by heat shock. Red blood cell (RBC) counts dropped to their lowest at 13 °C, while white blood cell (WBC) counts diminished significantly when temperatures dropped to 21 °C and then stabilized. Cortisol surged with temperature changes, peaking at 13 °C and 29 °C for cold and heat shock, respectively. Operculum movement was inversely affected by thermal changes, decreasing with cold and increasing with heat. These findings underscore the sensitivity of silver barb to thermal extremes, providing insights for optimized aquaculture management and enhanced resilience to environmental stressors.