Dietary tuna hydrolysate modulates growth performance, immune response, intestinal morphology and resistance to Streptococcus iniae in juvenile barramundi, Lates calcarifer

Abstract

This study investigated the effects of tuna hydrolysate (TH) inclusion in fishmeal (FM) based diets on the growth performance, innate immune response, intestinal health and resistance to Streptococcus iniae infection in juvenile barramundi, Lates calcarifer. Five isonitrogenous and isoenergetic experimental diets were prepared with TH, replacing FM at levels of 0% (control) 5%, 10%, 15% and 20%, and fed fish to apparent satiation three times daily for 8 weeks. The results showed that fish fed diets containing 5% and 10% TH had significantly higher final body weight and specific growth rate than the control. A significant reduction in blood glucose was found in fish fed 10%, 15% and 20% TH compared to those in the control whereas none of the other measured blood and serum indices were influenced by TH inclusion. Histological observation revealed a significant enhancement in goblet cell numbers in distal intestine of fish fed 5 to 10% TH in the diet. Moreover, fish fed 10% TH exhibited the highest resistance against Streptococcus iniae infection during a bacterial challenge trial. These findings therefore demonstrate that the replacement of 5 to 10% FM with TH improves growth, immune response, intestinal health and disease resistance in juvenile barramundi.

Effects of dietary visceral protein hydrolysate of rainbow trout on growth performance, carcass composition, digestibility and antioxidant enzyme in juvenileOncorhynchus mykiss

“…The protein availability and subsequent digestibility increased because of small polypeptide chains or short chains of amino acids that produced during the hydrolytic process (Silva, Rocha, Moreira, Signor, & Boscolo, ). Siddik, Howieson, Partridge, Fotedar, and Gholipourkanani () observed increased micromorphology of intestinal parameters such as fold height (hF), microvillous height (hMV) and external circumference of serosa (ECS) with the inclusion of PH in diets which could enhance growth performance of fish through increased nutrient uptake in more surface area, but Cahu, ZamboninoInfante, Quazuguel, and Gall () suggested the saturation of intestinal transport mechanisms by high luminal peptides and amino acids as a possible reason for inferior growth in some species. The appropriate level of PH supplementation can affect the improvement of growth indices (Siddik et al, ).…”

“…Siddik, Howieson, Partridge, Fotedar, and Gholipourkanani () observed increased micromorphology of intestinal parameters such as fold height (hF), microvillous height (hMV) and external circumference of serosa (ECS) with the inclusion of PH in diets which could enhance growth performance of fish through increased nutrient uptake in more surface area, but Cahu, ZamboninoInfante, Quazuguel, and Gall () suggested the saturation of intestinal transport mechanisms by high luminal peptides and amino acids as a possible reason for inferior growth in some species. The appropriate level of PH supplementation can affect the improvement of growth indices (Siddik et al, ). In addition, active peptides may be produced in the process of hydrolysis to enhance biological functions (Khosravi, Dio Bui, et al, ).…”

“…Likewise, significantly higher SOD levels were observed in juvenile red sea bream fed by PH diet (Dio Bui et al, ; Khosravi, Dio Bui, et al, ; Khosravi, Rahimnejad, et al, ). FPH containing free amino acids and suitable peptides (depending on the degree of hydrolysis) has a substantial role in maintaining suitable health of fish (Santos, Martins, Salas‐Mellado, & Prentice, ; Siddik et al, ). Other studies have also reported SOD elevations in response to dietary additions of antioxidant compounds such as vitamin E (Tocher et al, ), herbal essential oils (Sönmez et al, ), herbal extracts (Ahmed et al, ) and vegetable compounds (Tang et al, ).…”

Fish protein hydrolysate affected amino acid absorption and related gene expressions of IGF‐1/AKT pathways in turbot ( Scophthalmus maximus )

“…Previous researches on FPH showed that a low or moderate amount of FPH may improve feed intake, growth and other performances of fish and shrimps (Hevrøy et al, ; Mamauag & Ragaza, ; Ospina‐Salazar, Ríos‐Durán, Toledo‐Cuevas, & Martínez‐Palacios, ; Valle et al, ; Wei, Liang, Mu, Zheng, & Xu, ; Xu, Mu, et al, ; Zheng, Xu, Qian, Liang, & Wang, ), while high levels of FPH often reduced fish growth performance (Mach & Nortvedt, ). The negative effects of high FPH levels on fish performance were mainly due to an excessive amount of AAs and peptides in the intestine, which could induce the saturation and competition of transporters mechanisms (Ospina‐Salazar et al, ; Siddik, Howieson, Partridge, Fotedar, & Gholipourkanani, ). In aforementioned studies, the results of growth performance were obtained based on dietary fishmeal replaced by FPH.…”

Fermented Animal Source Protein as Substitution of Fishmeal on Intestinal Microbiota, Immune-Related Cytokines and Resistance to Vibrio mimicus in Freshwater Crayfish (Cherax cainii)

“…To incubate the cells for staining, the glass slide were placed in Giemsa solution for 20 min. Lysozyme (LYZ) activity was determined by the turbidimetric method described in Siddik et al (2018). Briefly, 5 mg of Micrococus lyso was mixed with 20 mL of PBS to prepare a bacterial suspension and stirred for 5 min.…”