Growth, body composition and hepatopancreas morphology of Nile tilapia fingerlings fed crude glycerol as a replacement for maize in diets

Crude glycerol in diets for Nile tilapia in the fattening stage

“…Therefore, the substitution of corn by crude glycerol is feasible and does not affect the efficiency of feed utilization of the Nile tilapia in the fattening stage. Studies with the same species, at different stages, also showed the noneffect of glycerol on the FCR values (Neu et al, 2012b(Neu et al, , 2013Costa et al, 2015;Meurer et al, 2016). Fish survival was not influenced by the inclusion of crude glycerol in diets (Table 2), which agrees with the results of Li et al (2010), Neu et al (2013), Gonçalves et al (2015), Costa et al (2015), and Meurer et al (2016).…”

“…Studies with the same species, at different stages, also showed the noneffect of glycerol on the FCR values (Neu et al, 2012b(Neu et al, , 2013Costa et al, 2015;Meurer et al, 2016). Fish survival was not influenced by the inclusion of crude glycerol in diets (Table 2), which agrees with the results of Li et al (2010), Neu et al (2013), Gonçalves et al (2015), Costa et al (2015), and Meurer et al (2016). However, lower survival of Nile tilapia fingerlings fed increasing levels of dietary glycerol was found by Neu et al (2012b); nonetheless, it should be noted that in this cited research, the mean experimental temperature was 21.4°C, which is below the level of thermal comfort (25 to 32ºC) for this species (El-Sayed & Kawanna, 2008), while in the present study the temperature was 26ºC.…”

“…Other studies also found no variation for the growth parameters of juvenile Nile tilapia, when up to 100 g kg -1 glycerol (Neu et al, 2013), or 150 g kg -1 glycerol (Costa et al, 2015) was added to their diets, namely in the final mean weight and in weight gain. Up to 110 g kg -1 glycerol can be included in diets of Nile tilapia in the post larvae stage, without affecting the final weight, according to Meurer et al (2016). However, it is important to note that glycerol effects were observed on Nile tilapia performance in other growth stages.…”

“…Glycerol has been proved to be a good alternative feed that can be used as source of energy for omnivorous fish (Li et al, 2010;Neu et al, 2013;Balen et al, 2014;Costa et al, 2015Costa et al, , 2017Moesch et al, 2016), in the meantime, the use of glycerol in the fattening stage of fish, as Nile tilapia, has not been sufficiently studied yet.…”

Hepatic Glycerol Metabolism-Related Genes in Carnivorous Rainbow Trout (Oncorhynchus mykiss): Insights Into Molecular Characteristics, Ontogenesis, and Nutritional Regulation

“…The inclusion of glycerol in aquafeeds has been mainly investigated in the omnivorous fish Nile tilapia (Oreochromis niloticus), showing that growth performance, voluntary feed intake, and protein efficiency could be affected depending on the inclusion level (Gonçalves et al, 2015). However, low inclusion levels of glycerol in this species (3-6%) did not alter growth performance, protein efficiency ratio, survival rate, lipid deposition, or hepatosomatic and viscerosomatic indexes compared to fish fed a diet without glycerol (Meurer et al, 2012(Meurer et al, , 2016Neu et al, 2013;Moesch et al, 2016). Another study in Nile tilapia has shown that this species is capable of metabolizing dietary crude glycerol into lipids, proteins, and/or carbohydrates, as well as into CO 2 , to provide energy (Da Costa et al, 2017).…”