Effect of Humic Substances as Feed Additive on the Growth Performance, Antioxidant Status, and Health Condition of African Catfish (Clarias gariepinus, Burchell 1822)

Abstract

In the present study, a possible nature immunostimulant and growth promoter—humic substances (HS) originating from Siberian leonardite mineraloid—were tested on juvenile Clarias gariepinus performance. Feed additive was applied onto commercial pelleted feed at four HS levels—0, 1, 3, and 6% w/w (HS0, HS1, HS3, HS6, respectively). Diets were tested in five repetitions (in total, n = 1800 individuals, mean body weight 28.1 ± 6.2 g) for 56 days. Growth and production parameters, fish condition and somatic indices, and overall mortality were evaluated after 14, 28, 42, and 56 days of exposure. Whereas, plasma samples were collected only after 0, 28, and 56 days, when fish health status was assessed with biochemical parameters (total proteins, TP; alanine aminotransferase, ALT; aspartate aminotransferase, AST; lactate dehydrogenase, LDH; cholesterol, CHOL; triglycerides, TAG) and fish antioxidant status with glutathione (reduced glutathione, GSH; oxidized glutathione, GSSG; glutathione ratio GSH/GSSG). Although a significantly positive effect of HS feed additive on growth performance was not found in the present study, moderately positive effects were found regarding biochemical parameters (ALT, AST, LDH, CHOL, and TAG) and antioxidants (GSH/GSSG ratio) that were improved especially in the HS3 group.

Effects of fulvic acid addition on laying performance, biochemical indices, and gut microbiota of aged hens

“…This may indicate that humic acid can protect the liver by reducing free radicals produced during liver metabolism (26). Nevertheless, in Prokešová et al (23) study, the activity of ALT, AST, and lactate dehydrogenase enzymes were within the species-specific optimal physiological range, and no differences were observed between the Clarias gariepinus tested groups after 28 and 56 days of HS feeding. Different results may be attributed to animal species, dosage, synthetic form, etc.…”

“…Interestingly, Domínguez-Negrete et al ( 22) found different dietary doses of humic acid did not significantly change the daily gain and feed conversion ratio. In the Prokešová et al (23) study, the humic substances (HS) incorporated into the diet (HS0-6) did not affect the production of Clarias gariepinus. However, broilers fed with FA gained significantly more body weight than those fed with control diets, and their FCR was also lower than those fed with control diets (11).…”

Application of haematology parameters for health management in fish farms

“…Some researchers believe that the content of CHOL, TP and Glu is positively correlated with the metabolic function of fish and their ability to adapt to harsh ecological environments. However, other studies have proposed that people with low plasma protein and albumin content have strong adaptability to the environment and a strong constitution 100 . The levels of ALB and TP in serum of crucian carp with haemolytic ascites disease are significantly lower than those of healthy fish.…”

“…However, other studies have proposed that people with low plasma protein and albumin content have strong adaptability to the environment and a strong constitution. 100 The levels of ALB and TP in serum of crucian carp with haemolytic ascites disease are significantly lower than those of healthy fish. In these cases, ALB reaches levels that are below 1% of that of healthy fish, while creatinine is significantly higher than that of healthy fish.…”

Sustainable Aquaculture: Nutrition Studies in Early Developing Finfish, Ornamentals and Experimental Model Fish

“…Prokešová et al [ 1 ] tested the effects of four levels (0, 1, 3, and 6% w / w ) of humic substances (HS) as natural immunostimulants and growth promoters in juvenile African catfish ( Clarias gariepinus ) during a 56-day exposure. Although growth was not improved by HS addition, moderately positive effects were observed regarding health status and antioxidant parameters, especially in the group receiving 3% HS.…”