Effect of Fermented Rice Bran used as Feed Ingredient on Apparent Digestibility Coefficient of Tilapia (Oreochromis niloticus) Feed

This study aimed to investigate the effect of fermented rice bran used as a feed ingredient on the apparent digestibility coefficient (ADC) of tilapia feed. The fermentation process was conducted under aerobic conditions using 2% Aspergillus niger for 24 hours. Moreover, three different types of feed were prepared with 3 replicates and these include treatment A (reference feed), B (unfermented rice bran feed), and C (fermented rice bran feed). These treatments were provided for the tilapia for 30 days. Meanwhile, the tilapia used had an average weight of 5 g/fish and reared using a recirculation system with a density of 16 fish/aquarium. The results showed that the value of ADCenergy (78.11%) in treatment C was significantly highest (P<0.05) compared to other treatments, while the lowest was in treatment B with 72.24%. The values of ADCdry matter (67.56%) and feed efficiency (64.20%) in treatment C were also higher (P<0.05) compared to treatment B with 57.02% and 54.74% respectively. However, there was no significantly difference (p>0.05) in the value of ADCprotein, ADClipid, and SGR among the treatments. These results indicate the rice bran fermented using A. niger is potential to be used as a raw material ingredient for tilapia feed.

ADDITION OF Aurantiochytrium sp. MEAL IN THE DIET AFFECTS IMMUNITY AND THERMAL SHOCK RESISTANCE OF THE PACIFIC WHITE SHRIMP

This paper reports the evaluation of digestibility, immunological parameters, and resistance to thermal shock at low temperature in Litopenaeus vannamei fed diets with diferent Aurantiochytrium sp. meal additions (0; 0.5; 1 and 2%). First, the apparent digestibility coefficient of the ingredient was determined. The digestibility of the microalgae meal was high for protein (74.90%); around 60% for lipids, and for docosahexaenoic fatty acid (DHA) it was 55.61%. After, shrimp rearing with the feed additive was carried out in a clear water system, containing 25 shrimp (initial weight: 4.89 ± 0.27 g) per 400 L tank. Feeding occurred four times a day. After a three-week period, immunological parameters were evaluated and thermal shock was performed. Animals fed 0.5% and 2% of the microalgae Aurantiochytrium sp. showed higher survival to thermal shock. In immunological analyses, the serum agglutiniting titer was higher (p <0.05) in the 0.5 and 2% additions of the microalgae meal, and the phenoloxidase activity (PO) was higher in the 1% addition (p <0.05). It is concluded that there is good utilization of the nutrients of Aurantiochytrium sp. meal by L. vannamei and its addition to the diet (0.5 and 1%) increased shrimp resistance to thermal shock.

Replacement of fish meal with defatted and fermented soybean meals in pompano Trachinotus blochii (Lacepède, 1801) diets

This study was conducted to examine the effects of the replacement of fish meal with defatted and fermented soybean meals on the growth performance, apparent nutrient digestibility, bile acid levels, and digestive enzyme activity of pompano Trachinotus blochii (Lacepède, 1801). Four diets were formulated to replace 40% of fish meal with defatted soybean meal (SBM), SBM fermented by Bacillus subtilis TH2 (FSBM1) or SBM fermented by B. subtilis B3 (FSBM2). The diets are denoted as follows: FMD (fish meal-based diet, used as a Control), SBMD (fish meal replaced by SBM diet), FSBM1D (fish meal replaced by FSBM1 diet), and FSBM2D (fish meal replaced by FSBM2 diet). Thirty fingerling pompanos with an initial body weight of 15.3 ± 0.3 g were allocated to each of eight indoor polyvinyl chloride tanks (500 L capacity), with two replicate tanks per dietary treatment. For 8 weeks, fish were hand-fed the experimental diets to apparent satiation twice daily. The final body weight, weight gain, specific growth rate, and feed conversion ratio of fish fed SBMD and FSBM1D were significantly inferior to those in fish fed FMD (P<0.05). These parameters were not significantly different between the FSBM2D and FMD experimental groups (P>0.05). Fish fed SBMD showed significantly lower plasma total cholesterol, whole body lipids, intestinal total bile acids and lipase activity than those fed FMD, whereas no significant differences were observed among fish fed FSBM1D, FSBM2D, and FMD. Trypsin activity and protein apparent digestibility coefficient were not significantly affected by the experimental diets. However, lipid apparent digestibility coefficient was significantly lower in fish fed SBMD and FSBM1D rather than FMD. There was no significant difference in lipid apparent digestibility coefficient between the FMD and FSBM2D experimental groups. The results indicated that SBM decreased bile acid levels, lipase activity, lipid digestibility, and growth performance in pompano fish. These parameters were increased by the inclusion of B. subtilis B3 fermented SBM in the diet, thus suggesting that fermentation of SBM with B. subtilis B3 may be an effective way to improve bile acid levels, lipase activity, lipid digestibility, and growth performance of pompano fed an SBM-based diet.

Apparent nutrient digestibility of carbohydrate (corn) in Cirrhinus mrigala under the influence of chromium chloride hexahydrate

A feeding trial was carried out to assess the effect of dietary chromium supplementation on apparent nutrient digestibility coefficient (%) of gelatinized and non-gelatinized corn in Cirrhinus mrigala fingerlings for 90 days. Using various levels of chromium chloride hexahydrate six test diets designated as T1 (G/0.0 Cr2Cl3.6H2O mg Kg-1), T2 (NG/0.0 Cr2Cl3.6H2O mg Kg-1), T3 (G/0.2 Cr2Cl3.6H2O mg Kg-1), T4 (NG/0.2 Cr2Cl3.6H2O mg Kg-1), T5 (G/0.4 Cr2Cl3.6H2O mg Kg-1) and T6 (NG/0.4 Cr2Cl3.6H2O mg Kg-1) were prepared. Results showed highest apparent digestibility coefficient (ADC) of nutrients dry matter, crude lipid and gross energy in test diet T5 that was gelatinized and supplemented with chromium 0.4 mg/Kg while, for crude protein higher value of nutrient digestibility was recorded in T3 test diet (G/0.2 Cr2Cl3.6H2O mg/Kg). It was concluded that chromium supplementation with gelatinized corn in fish (Cirrhinus mrigala) diet can improve the nutrients digestibility more efficiently.

Apparent digestibility in marine mutton snapper juveniles and digestive activity of enzymes

The marine species of snapper, Lutjanus analis, has carnivorous eating habits and with potential for cultivation. The aim of this study was to evaluate the apparent digestibility coefficient (CDA) of mutton snapper, and to evaluate its enzymatic profile after feeding with vegetable and animal protein sources. CDA was the indirect method of fecal collection, using chromic oxide as a biological marker. Eight hundred fish, with an average weight of 28.0 ± 2.58 g, were acclimated for 15 days in a net tank (2 m³), ​​and installed in the same collection environment. The acclimatization of 54 fish was carried out in digestibility aquariums (200 L), and the collection of feces started. For mutton snapper, the supply of octopus flour improves (P <0.05) the digestibility of dry matter (CDAMS, 67.17%), crude protein (CDAPB, 90.9%) and crude energy (CDAGE, 78, 8%). Regarding the digestibility of lipids (CDAL), anchovy flour has more (P <0.05) digestible lipids (78.1%), followed by the tested ingredients, fish meal (72.4%) and flour octopus (69.7%). Apparent digestibility of dry matter, crude protein and crude energy were low (P <0.05) for shrimp meal and soybean meal. Mutton snapper fed with octopus flour has higher digestibility coefficients, suggesting this ingredient for species. All diets caused low amylase activity in juveniles, and lipase and alkaline protease activities were higher with the inclusion of broadband anchovy flour and octopus flour, respectively.

GARLIC POWDER IN RATIONS FOR NILE TILAPIA

The This study evaluated the effect of levels of garlic powder (0.0, 1.0, 2.0 and 3.0 g.kg-1) added to diets for Nile tilapia on animal performance, villi height and diet digestibility. The rations consisted of pellets and tilapia and were fed to apparent satiation for 60 days. 120 fish, with initial average weight of 4.20 ± 0.4 g, were masculinized and distributed in 24 aquariums of 70L in a randomized design consisting of four treatments and six replications in a closed circulation system with constant aeration. 240 fishes was used for feces collected by an indirect method (Guelph modified system) and estimation of coefficients of apparent digestibility using 0.5 g.kg-1 of chromic oxide as an inert indicator incorporated into the ration. No significant differences in performance related to organ weight, the hepato-somatic index, the viscero-somatic fat index and villi height were observed. However, the apparent digestibility coefficient of rations was negatively affected by the addition of garlic powder. Garlic powder as an additive in rations for Nile tilapia did not provide positive effects as a growth promoter and worsened the digestibility of nutrients among the tested treatments.

Digestibility of Insect Meals for Nile Tilapia Fingerlings

Insects are a valuable source of nutrients for fish, but little is known about their nutritional value for Nile tilapia fingerlings. To evaluate the nutritional value and energy apparent digestibility coefficient (ADC) of five insects for Nile Tilapia male fingerlings, 900 fish were distributed in 18 fiberglass conic tanks, in a completely randomized design, with six dietary treatments (control, Nauphoeta cinerea meal (NCM) (Blattodea), Zophobas morio larvae meal (ZMM) (Coleptera), Gromphadorhina portentosa meal (GPM) (Blattodea), Gryllus assimilis meal (GAM) (Orthoptera) and Tenebrio molitor larvae meal (TMM) (Coleptera)) and three replicates (tanks), each containing 50 fish. The control diet had no insect meal included and the other five treatments comprised 80% commercial diet and 20% test ingredient with 0.1% chromic oxide as an inert marker. TMM presented a higher ADC for dry matter, protein, corrected protein and chitin than to other treatments (p < 0.01). GPM presented the highest ADC for lipids (p < 0.01). In general, the TMM presented better ADC of nutrients and energy and all the insect meals evaluated are potential feed for Nile tilapia fingerlings.