Effect of Fenugreek as a Feed Additive on the Growth, Body Composition and Apparent Nutrients Digestibility of Striped Catfish Pangasius hypophthalmus Fry

Determination of heavy metals (Pb, Cr, As, Hg, and Cd) into the body organs of selected fish, water, sediment, and soil samples from Head Punjnad and Head Taunsa, Punjab, Pakistan

The present study was conducted on Head Punjnad (HP) and Head Taunsa (HT) to evaluate the contamination of Pb, Cr, As, Hg, and Cd in water, soil, sediment, fish as a whole and fish organs. Fish, water, soil and sediment samples were collected from different sites of HT and HP on a monthly basis for 8 months. Heavy metals in water, soil, and sediment were determined by a polarized Zeeman atomic absorption spectrophotometer and in fish and fish organs by an atomic absorption spectrophotometer. Contamination of Cd, Hg, and As was significantly (P<0.05) higher in water of HP as compared to HT, while Cr showed a non-significant (P>0.05) difference at HP and HT. Pb was significantly (P<0.05) higher in water of HT as compared to HP. In the case of soil, Cd, Hg, and Pb were higher at HT as compared to HP, while As and Cr were significantly (P<0.05) higher at HP as compared to HT. In sediment, contamination of Cd, Hg, and As were significantly (P<0.05) higher at HP as compared to HT, while the Cr difference was non-significant (P>0.05) but Pb showed a significantly (P<0.05) higher value at HT than HP. Cd accumulation in different fish species was recorded as R. rita ˃O. niloticus ˃C. marulius ˃S. sarwari ˃C. idella ˃C. catla ˃N. notopterus ˃E. vacha ˃L. rohita ˃C. carpio, respectively. Hg as O. niloticus ˃S. sarwari ˃R. rita ˃C. marulius ˃C. catla ˃N. notopterus ˃E. vacha ˃L. rohita ˃C. carpio ˃C. idella, respectively. As as O. niloticus ˃R. rita ˃S. sarwari ˃C. marulius ˃C. catla ˃C. carpio ˃N. notopterus ˃C. idella ˃E. vacha ˃L. rohita, respectively. Cr accumulation recorded as L. rohita ˃C. idella ˃O. niloticus ˃C. marulius ˃E. vacha ˃R. rita ˃C. catla ˃C. carpio ˃S. sarwari ˃N. notopterus, respectively. Pb accumulation in different fish species was recorded as C. idella ˃C. carpio ˃N. notopterus ˃L. rohita ˃O. niloticus ˃C. marulius ˃R. rita ˃S. sarwari ˃E. vacha ˃C. catla, respectively. Cd accumulation in different organs was recorded as kidney ˃liver ˃gills ˃muscle ˃skin ˃scale. Hg accumulation in different organs was recorded as kidney ˃gills ˃liver ˃skin ˃muscle ˃scale. As accumulation in different organs was recorded as kidney ˃liver ˃gills ˃muscle ˃skin ˃scale. Cr accumulation in different organs was recorded as gills ˃ liver ˃skin ˃muscle ˃kidney ˃scale. Pb accumulation in different organs was recorded as gills˃ kidney˃ skin˃ liver˃ muscle˃ scale.

Lernaeid parasites prevalence in commercial freshwater fish species at various fish farms in Pakistan

Reports abound on Lernaea parasitizing the brood stock, fingerlings, and marketable-sized culturable freshwater fish species in various parts of the world. We investigated seven small-scale aquaculture farms and how the prevailing Lernaea is impacting them. Randomly seven fish farms were selected to determine the prevalence percentage of lernaeid ectoparasites. Relevant information of the fishponds to estimate the various aspects such as effects of water source and quality, feed, stocking density, treatment used, and weight and length of fish, concerned with Lernaea infestation and prevalence was gathered. The results indicated that Catla catla (F. Hamilton, 1822) showed highest prevalence (41.7%) among the seven fish species, whereas Oreochromis niloticus showed zero. Other five fish species Ctenopharyngodon idella, Cirrhinus cirrhosis, Cyprinus carpio, Labeo rohita and Hypophthalmichthys molitrix showed 13.2%, 8.1%, 7.7%, 7.4%, 0.9% prevalence, respectively. In Royal Fish Farm 84.3% lernaeid infestation was observed, while no parasite was observed in the Vicent's Chunnian fish farm. The water source, quality, feed, fertilizers, stocking density, water temperature, and potential treatment options displayed varying tendencies among fish farms and prevalence. Depending on the weight and length, the highest prevalence (56.7%, and 66.7%) was observed in 3501-4000 g and 81-90 cm groups. The infestation rate varied in various fish body parts with the dorsal fin the most vulnerable organ and showed 2.3% overall prevalence (while 18.4% contribution within total 12.6% infestation). Out of 147 infected fish samples, 45 were extensively contaminated by Lernaea spread. In conclusion, our findings confirm that Lernaea could pose a considerable threat to marketable fish, and various treatment options should be educated to the farmers to help mitigate the spread and potential losses. Furthermore, Catla catla is more vulnerable to Lernaea infestation (41.7%), so are the fish species being cultured at higher stocking densities.

Body composition, growth performance and enzyme activities of Labeo rohita fed different commercial fish feeds

We have evaluated the effects of different fish feeds on the body composition, growth, and enzyme activities of Labeo rohita (Rohu). In total, 240 fishes between the average weights of 24.77±2.15g were studied. The treatments were applied in a completely randomized design, with 4 treatments of 60 fishes each. Treatments consisted of four different fish feeds [Oryza (T1), AMG (T2), Aqua (T3), and Supreme (T4)]. Body composition, growth performance, and enzyme activities were evaluated. There was a significant variation in performance of fishes fed with different type of feed; as fishes having Oryza feed showed the highest weight gain, specific growth rate (SGR), and best feed conversion ratio (FCR) as compared to other groups that were considered to be significant (P ≤ 0.05). High net weight gain was obtained in T4 when compared with T2 and T3. FCR value of T4 was less than T1 but higher than T2, T3 and T2, which showed the lowest values. The specific growth rate was recorded as average in T4, but T2 led a high SGR than T3. Similarly, crude protein level and digestive enzymes activity was recorded significantly highest in fed with Oryza (T1) as compared to AMG (T2), Aqua (T3), and Supreme (T4). Water quality parameters were recorded significant in all treatments except pH and DO of treatment (T1), significantly different from other treatments. It was concluded that Rohu (Labeo rohita) could show a promising growth rate and protease enzyme activity when fed with the Oryza feed of 25% protein.

The Gene Regulatory Roles of Herbal Extracts on the Growth, Immune System, and Reproduction of Fish

The crucial need for safe and healthy aquatic animals obligates researchers in aquaculture to investigate alternative and beneficial additives. Medicinal herbals and their extracts are compromised with diverse effects on the performances of aquatic animals. These compounds can affect growth performance and stimulate the immune system when used in fish diet. In addition, the use of medicinal herbs and their extracts can reduce oxidative stress induced by several stressors during fish culture. Correspondingly, aquatic animals could gain increased resistance against infectious pathogens and environmental stressors. Nevertheless, the exact mode of action where these additives can affect aquatic animals' performances is still not well documented. Understanding the mechanistic role of herbal supplements and their derivatives is a vital tool to develop further the strategies and application of these additives for feasible and sustainable aquaculture. Gene-related studies have clarified the detailed information on the herbal supplements' mode of action when administered orally in aquafeed. Several review articles have presented the potential roles of medicinal herbs on the performances of aquatic animals. However, this review article discusses the outputs of studies conducted on aquatic animals fed dietary, medicinal herbs, focusing on the gene expression related to growth and immune performances. Furthermore, a particular focus is directed to the expected influence of herbal supplements on the reproduction of aquatic animals.

Biological Health Assessments of Lotic Waters by Biotic Integrity Indices and their Relations to Water Chemistry

Biological health assessment (BHA) has developed as an imperative gauge in efficient management of freshwater resources and fish assemblages. The principal objective of this research is directed at the development and application of a new index under the umbrella of the famous index of biological integrity (IBI). Further, we intended to carry out comparative assessments of the new index with two existing indices and testified to their rational in Geum River watershed, which is the third largest river water basin in South Korea. We analyzed the biotic integrity of 149 different study sites in the streams and rivers of Geum River watershed, perusing fish assemblages and water quality data. The results revealed the newer index, i.e., multi-metric (mm) IBI 06 (mmIBI 06 metrics), as comparatively more efficient than previously used indices, i.e., mmIBI 08 and mmIBI 11. Furthermore, the linear regression and correlational analyses indicated harmonic relation of mmIBI 06 with mmIBI 08 (R2 = 0.85) and mmIBI 11 (R2 = 0.87). Nonetheless, linear regression modeling discovered a very strong positive relation between mmIBI 08 and mmIBI 11 (R2 = 0.91), thereby implying previously used indices demonstrate better approximation. In significant contrast to both old indices, the newer index exhibited improved facility to better classify the study sites between the assortments of ‘excellent to very poor’ compared to old indices elucidated one-step lower, i.e., from ‘excellent to poor’. For instance, the newer index categorized 60 sites as ‘very poor’, requiring immediate attention owing to biological degradation. Additionally, the newer index endures grander ability to indicate sites requiring immediate management or restoration attention with a plausible site classification, especially in relation to the invasive alien species (IAS). The water chemistry was mainly influenced by rampant anthropogenic actions compounded by intensive monsoon precipitation that may relinquish highly suitable grounds for invasive alien fish species. This may eventually lead to severe biological degradation and successive deterioration of habitat by the IAS. In conclusion, the newer index endures ample capacity to indicate the fish community disturbances in rivers and streams. Further, correlation, linear regression, as well as principal component analysis (PCA) analyses on biotic indices and water chemistry showed higher approximations. Therefore, our newer index would be a valuable BHA tool to classify and elucidate the streams and rivers by indicating sites necessitating preferred attention and restoration measures.