Withania coagulans fruit extract: a possible useful additive in ameliorating growth and immunity of Labeo rohita (Hamilton, 1822)

Nettle (Urtica dioica) supplementation: impact on growth, hematology, immune response, and resilience to Aeromonas hydrophila in Labeo rohita fingerlings

The significance of plant-derived products in aquaculture lies in their potential to offer sustainable alternatives, promoting eco-friendly practices. This study investigated the impact of nettle (Urtica dioica) leaves powder on the growth efficiency, hemato-biochemical variables and non-specific immune system of rohu, Labeo rohita fingerlings. To achieve this objective, sample average weight (5.23 ± 0.34 g) were categorized into four groups, namely control, T1, T2 and T3 in triplicate and administered diets fortified with nettle in amounts of 0, 1, 3 and 5% respectively for a duration of 60 days. After 60 days of fortified diet, the fish underwent intraperitoneal injection with bacteria (Aeromonas hydrophila), and subsequent relative percentage survival (RPS) was observed. The growth performance, including "weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR) and feed efficiency ratio (FER)", were notably higher in the T3 group (5%) than in others. The hematological values of White blood cell, hematocrit, and hemoglobin revealed higher levels with a fortified diet. The dietary supplementation of nettle reduced serum cholesterol and glucose concentration, whereas it increased albumin, globulin, and total protein in the fish blood. Enhancements in lysozyme and myeloperoxidase activity were observed in the intervention groups with feed containing nettle supplementation. The nettle diet at a 5% concentration demonstrated a higher RPS than the others following injection with A. hydrophila. The findings indicate the potential of nettle as a valuable nutritional supplement for increasing fish immunological reaction and bolstering pathogen resistance.

Dietary Effect of Withania somnifera Root Powder on Growth, Hematobiochemical Parameters, Immunity, and Disease Resistance to Aeromonas hydrophila in Cyprinus carpio

This study investigates the influence of Withania somnifera root powder (WSRP) on different aspects of common carp (Cyprinus carpio), including growth, hematobiochemical parameters, antioxidant status, nonspecific immune response, and resilience to bacterial infections. Over a 60-day period, 180 common carp fingerlings (11.73 ± 0.52 g) were subjected to diets supplemented with increasing WSRP levels (0 (control), 1% (WSRP1), 2.5% (WSRP2.5), and 4% (WSRP4)). Nonspecific immune parameters were evaluated using serum samples collected at intervals of 0, 20, 40, and 60 days. After the feeding trial, the fish underwent experimental challenge with Aeromonas hydrophila, and relative percentage survival (RPS) was monitored for 14 days. The findings revealed a considerable (p  < 0.05) enhancement in growth performance and a decreased feed conversion ratio (FCR) with increasing WSRP supplementation. Additionally, hematological and biochemical profiles exhibited improvements in groups receiving WSRP-enriched diets. Fish serum antioxidant status showed a significant (p  < 0.05) increase, as indicated by increased activities of total antioxidant capacity (TAC), superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) in WSRP4. WSRP-supplemented diets led to remarkable enhancements in lysozyme activity (p = 0.001), phagocytic activity (p = 0.002), and RPS (p = 0.003), peaking in WSRP4 at day 60. Furthermore, WSRP2.5 and WSRP4 demonstrated a substantial decrease (p  > 0.05) in serum glucose and cortisol levels compared to other groups. In conclusion, WSRP proves valuable for enhancing growth, blood parameters, antioxidant balance, immune response, and infection resistance in common carp, especially at 2.5%-4% dietary supplementation levels. In the future, it will be crucial to study the long-term effects of WSRP supplementation on fish health, as well as its potential for large-scale aquaculture and economic viability in the aquafeed industry.

Human Health Risk Assessment due to the Incidence of Heavy Metals in Different Commercial Feeds Used for the Culturing of Biofloc Fish (Nile tilapia: Oreochromis niloticus)

Fish meat is a major and rich source of white protein; its quality is determined by the fish feed. However, the low-quality feed may contribute to a source of contamination if it does not fulfill the standard protocol. Biofloc is considered one of the most efficient, successful aquacultures, but this system is still under investigation for its efficiency and safety. Thus, current study focused on the heavy metal contamination in biofloc fish fed on different commercial feeds and human health risk analysis. Samples of extensively used three feeds (Supreme™, Hitech™, and MH-Aqua™), tanks water, and biofloc fish (gills, liver muscle) were collected for heavy metals (Cu, Cd, Pb, and Cr) analysis using atomic absorption spectrometry. An experiment was designed by dividing the fish into three groups: group 1 (Supreme™), group 2 (Hitech™), and group 3 (MH-Aqua™). A bioaccumulation factor and human health risk assessment have been calculated to measure fish and human health. Results revealed that most of the heavy metal concentration was higher (P < 0.05) in MH-Aqua™ feed compared to others. Similarly, heavy metal concentration was higher (P < 0.05) in the water of group 3, where fish was cultured on MH-Aqua™ feed. However, in the fish gills, liver, and muscle, the heavy metal concentration was significantly greater in group 3 fed on MH-Aqua™ feed, followed by group 1. Heavy metals in all feeds were positively correlated to the heavy metal concentration of the fish muscles. The bioaccumulation factor for Cu and Pb was higher in the fish liver, Cd and Cr in the case of fish gills, and least in the fish muscle. EDI and THQ values vary in all the groups, while the HI value was found lower than 1 in group 1 and group 2 but higher in group 3 fed on MH-Aqua™ feed. Strict checks and balances in formulating a diet will be helpful to progressively lower the amount of dangerous heavy metals.

Assessment and Bioaccumulation of Heavy Metals in Water, Fish (wild and Farmed) and Associated Human Health Risk

Worldwide, anthropogenic activities are causing the natural environment and aquaculture systems to become heavily contaminated with heavy metals, which can lead to consumer's health problems. In the current study, wild and farmed fish (n = 30) and water samples (n = 6) have been collected from the Chashma barrage and fish farm to assess the heavy metals concentration, i.e., Cu, Cd, Pb, Zn and Cr, in the water and some important organs (gills, liver, muscle, brain and bones) of wild and farmed fish (Labeo rohita) using Graphite furnace Atomic absorption spectrometry. Bioaccumulation factor and human health risk assessment were calculated to measure the health status of both fish and humans. Results show that in wild and farm fish's gills, muscles and bones, the trend of the heavy metals was Zn > Pb > Cu > Cd > Cr. On the other hand, the brain and liver show Zn > Cu > Pb > Cd > Cr trend. Comparatively, the heavy metals concentration was mostly higher (P < 0.05) in wild fish. Further; in both fish habitats (water) the heavy metals (Cd and Pb) concentration was higher than the WHO standard level, while in the body, Cd was higher (P < 0.05) in all studied organs except the muscle, Cr was only lower (P > 0.05) in muscle and brain. Pb was higher (P < 0.05) in all studied organs of both fish. Bioaccumulation of heavy metals was mostly higher (P < 0.05) in wild fish than in farmed. EDI and THQ were higher in wild fish, but the HI value was lower than 1 for both fish. Moreover, the PCA analysis suggests a positive correlation between heavy metals concentration in fish organs and the water of both fish (wild and farmed). Results indicated that farmed fish showed less potential risk to humans than wild fish.

Evaluation and Association of Heavy Metals in Commonly Used Fish Feed with Metals Concentration in Some Tissues of O. niloticus Cultured in Biofloc Technology and Earthen Pond System

For successful aquaculture, the primary need is the quality of fish feed, which determines fish flesh quality. The current study was conducted to evaluate the number and concentration of heavy metals in commonly used fish feeds and fish gills, liver, and muscle of biofloc technology and earthen pond systems. Besides this, the correlation between heavy metals in fish feeds with detected metals in the gills, liver, and muscle of fish was also determined. Results revealed that heavy metals concentration, including Cu and Cd, in feed B was significantly greater than in feed A, but the Zn level in feed A was significantly higher than in feed B. Furthermore, the concentration of heavy metals in fish of both aquaculture systems was significantly higher in the liver than in the gills and muscle. The metal concentration in fish feeds and fish edible parts (muscle) was lower than the WHO standard level; however, the amount of Pb was higher in the fish muscle, which is harmful for human consumption. Though the correlation test revealed that all of the metals from the feeds were positively correlated to the metals detected in the fish, but most of the estimated correlation was insignificant. From the current study, it can be concluded that the fish feed producers need to measure feed quality adequately to avoid hazardous contamination by heavy metals in the feed. The ultimate consumer, fish and humans, may, otherwise, be predisposed to assimilate and accumulate these heavy metals.