An eight-week feeding trial was conducted to evaluate the supplementation of pineapple waste extract (PWE) at levels of 0%, 1%, 2%, and 3% on growth performance of Nile tilapia (8.76 ± 0.17 g) for 8 weeks. PWE supplementation improved pepsin digestibility significantly but not protein digestibility. Thus, fish fed PWE showed better growth than those fed the control feed. The fish fed the feed supplemented with 1% PWE resulted in the optimum protein digestibility, growth, and feed utilization (P < 0.05). No significant differences among dietary treatments were found for free ammonia and total nitrogen excretion (P > 0.05).

This study used pineapple waste crude extract (PWCE) to increase the potential of Pacific white shrimp (Litopenaeus vannamei) production for food sustainability and stability. The objective was to investigate the appropriate technique to increase the yield production and quality of shrimp and decrease waste from shrimp culture. Pacific white shrimp (average body size: 0.51 g) were fed with commercial feed supplemented with PWCE at various concentrations of 0 (control), 90, 170, and 250 ppt. Shrimp were fed five times per day for 80 days. At the end of the trial, the results showed that shrimp fed with the PWCE 250 ppt supplementation provided the highest growth rate and the best feed utilisation and yield ( ). The protein content of whole shrimp in all shrimp fed with the PWCE supplementation diet was higher than that in the control group ( ). On the contrary, the variation of endogenous digestive enzymes, including protease, trypsin, and the T/C ratio, was significantly lower in shrimp fed a diet supplemented with PWCE 250 ppt ( ). While in this group, the number of microorganisms on thiosulfate-citrate-bile salt-sucrose (TCBS), blood agar, and trypticase soy agar (TSA) was lowest ( ). Furthermore, the dietary PWCE at 250 ppt increased the volume of microvilli in the hindgut of shrimp, but the supplementation at 170 ppt improved the number of F-cells in the epithelial cells of the hepatopancreas. Nevertheless, the supplementation of PWCE in the diet did not affect the water quality ( ). Therefore, pineapple waste crude extract supplementation improves both quantitative and qualitative yields and tends to reduce waste.

Creatine plays a vital part in the energy metabolism and physiological roles. It is exclusively found in ingredients of animal origin, so using all‐plant protein‐based diets increases the risk of creatine deficiency. The objectives of this current study were to determine the optimal level of dietary guanidinoacetic acid (GAA) with regard to the nutrient digestibility, growth performance, feed utilization and carcass quality of Nile tilapia (Oreochromis niloticus). The fish (27.33 ± 0.70 g) were fed with five different isonitrogenous and isoenergetic diets for 60 days: T1 was the positive control diet (HF; 6% fish meal inclusion); T2 was the negative control formulated to contain no GAA (NC, free fish meal); and T3, T4 and T5 were NC supplemented with 0.06%, 0.12% and 0.18% of GAA respectively. At the end of the experiment, it was found that growth performance and feed utilization were not significantly different (p > .05) among the groups. However, fish from the T3 and T4 groups had slightly better weight gain and growth rate, as well as improved digestibility of protein, methionine, lysine and histidine (p < .05). Fish fed the dietary GAA at 0.06 or 0.12% had clearly larger width increment than the other groups. This is important as consumers prefer large dorsal muscles. This result from this study showed no adverse effect on haematological parameters, serum biochemistry parameters, fillet texture quality and histopathological change in the liver of Nile tilapia. Therefore, these results indicate that GAA supplementation at 0.06%–0.12% in Nile tilapia diet can potentially improve fish growth and feed utilization without setback on health.