Redalyc.Apparent digestibility of energetic ingredients by pirarucu juveniles, Arapaima gigas (Schinz, 1822)

ABSTRACT. An understanding of feed ingredient digestibility for the pirarucu is a fundamental step in the development of feeds that promote proper growth of the specie while in captivity. A digestibility trial was conducted with four treatments in triplicate (corn starch, corn, rice bran and wheat bran) to evaluate the digestibility of dry matter, gross energy, crude protein and amino acids by the pirarucu. We used indirect methodology with the inclusion of chromium oxide at 0.1% in the feeds. In total, 18 juveniles were used, with an average live weight of 235 ± 36 g. The sampled juveniles were trained to consume the feeds prior to testing. The corn and cornstarch presented the best apparent digestibility coefficients (ADCs) of dry matter, with 76.37% and 70.66%, respectively, followed by rice bran (46.23%) and wheat bran (45.13%). The best ADCs of crude protein were observed in corn (93.44%) and cornstarch (90.94%) compared to rice bran (68.23%) and wheat bran (68.58%). There was no significant difference in the ADC of gross energy; the values ranged from 47.10% for corn starch to 40.10% for corn. The corn and corn starch presented the best ADCs for all the amino acids evaluated, followed by rice bran and wheat bran

Performance of juvenile mojarra supplied with feed containing varying levels of crude protein

ABSTRACT The growth of the Brazilian aquaculture has stimulated the development of the productive chain of native species, including marine environment. The objective of this study was to evaluate the growth performance of juvenile mojarra fish (Diapterus rhombeus) fed diets containing different concentrations of crude protein (32, 36, 40 and 44 g 100 g-1). The 80 juvenile mojarra (7.2±1.5 g) were kept in 16 circular tanks (150 L). The study design used was completely randomized with four treatments and four repetitions. The fish were fed four times a day. At the end of the experiment (60 days) the final weight, feed intake, weight gain (WG), feed:gain ratio (FGR), protein efficiency rate (PER), energy efficiency rate, specific growth, survival rate and, body composition were evaluated. It was verified significant effect of protein level on the WG, with the best value at the level of 38.20 g 100 g-1 of crude protein. For FGR, the best estimated value occurred with 38.06 g 100 g-1 of crude protein, similar to that reported for the PER (38.91 g 100 g-1). The other performance parameters and body composition were not influenced by crude protein levels. Diet crude protein concentrations between 38.06 and 38.91 g 100 g-1 provide the best performance indices for juvenile mojarra

Digestibility of animal and vegetable protein ingredients by pirarucu juveniles, Arapaima gigas

ABSTRACT The objective of this study was to determine the apparent digestibility coefficients of energy, protein, and amino acids in protein ingredients by pirarucu juveniles. A test was conducted with six protein ingredients: meat and bone meal, fish meal, hydrolyzed feather meal, poultry by-product meal, soybean meal, and corn gluten meal. Three repetitions were used for each tested ingredient. A reference feed was used with 430 g kg−1 crude protein and 19.63 kJ g−1 gross energy. The test feeds consisted of the replacement of 30% of the reference feeds with the test ingredients. Chromium oxide was added to the feeds at 1 g kg−1 as an external marker. Eighteen juveniles with an average weight of 235±36 g were used. The best apparent digestibility coefficients of protein were found for fish meal, followed by the poultry by-product meal and meat and bone meal. However, except for gluten, all the tested ingredients presented protein digestibilities above 0.70. The crude energy apparent digestibility coefficient was higher for animal ingredients, above 0.75, than for vegetable ingredients, which presented values below 0.60. Pirarucu efficiently uses the protein from the tested ingredients, regardless of origin. However, it has a preferential ability to use the energy from animal ingredients

Performance and economic analysis of the production of Nile tilapia submitted to different feeding management

The productive performance and the variable cost of production were evaluated for different feeding strategies for tilapia during the production cycle. A sample of 2,000 juvenile tilapia was distributed (23.55 ± 2.38 g) into five treatments and with four repetitions as follows: C (feed consumption to apparent satiety), R20 (beginning feed restriction when fish reached an average weight of 20 g), R200 (beginning feed restriction when fish reached an average weight of 200 g), R400 (beginning feed restriction when fish reached an average weight of 400 g) and R600 (beginning feed restriction when fish reached an average weight of 600 g). The fish were given extruded commercial feed containing 34% crude protein until they reached a weight of 200 g, at which time they received feed containing 32% crude protein. Monthly biometrics were performed in order to determine the food restriction starting point, which was one day of restriction followed by six feeding days. The following parameters were evaluated: water quality, productive performance variables, the variable costs of production and excreted nitrogen. The results were subjected to analysis of variance, and the means were compared using Tukey’s test (5% significance). No statistical differences were observed in final weight, weight gain, feed consumption, feed conversion or survival. The fish from the R20 treatment had the lowest variable cost of production (g fish-1) and the lowest nitrogen excretion into the water. This suggests that feed restriction from the early stages of life does not compromise the productive performance and contributes to reducing the variable costs and the quantity of nitrogen excreted into the environment. Thus, a one-day per week feed restriction strategy can be applied from the earliest stages of life without compromising the productive performance or body composition of Nile tilapia. This strategy can also reduce variable costs of production by means of reducing relative labour and feed costs. </p

Digestibility and performance of juvenile Nile tilapia fed with diets containing forage palm

O suprimento das necessidades nutricionais de forma econômica é essencial para o sucesso de qualquer produção animal. A palma forrageira é uma cactácea bem adaptada as regiões semi-áridas, sendo comumente utilizada na alimentação de ruminantes, entretanto estudos com peixes são escassos. Objetivou-se avaliar a digestibilidade de farelos de cinco cultivares de palma forrageira (Opuntia fícus) para juvenis de tilápia nilótica e posteriormente o desempenho dos juvenis recebendo níveis crescentes da cultivar com melhor coeficiente de digestibilidade aparente da proteína bruta (CDAPB) (75,2%). No experimento de digestibilidade foram utilizados 90 juvenis de tilápia nilótica masculinizadas (com peso médio de 6,02 ± 0,65 g), para determinar os coeficientes de digestibilidade aparente da matéria seca (CDAMS), energia bruta (CDAEB) e proteína bruta dos cultivares (Orelha de onça, Miúda, Gigante, Comum e IPA 20). O delineamento experimental foi inteiramente casualizado (DIC) com cinco tratamentos e três repetições. No experimento de desempenho 300 juvenis de tilápia nilótica masculinizados (peso médio de 1,39 ± 0,12 g) receberam rações com diferentes níveis de inclusão (0, 72, 144 e 216 g Kg-1) do farelo de palma-cultivar IPA 20, em um DIC com quatro tratamentos e cinco repetições. Foram observadas diferenças significativas (P < 0,05) para o CDAMS e o CDAPB entre os tratamentos. As cultivares que apresentaram maiores CDAMS foram a IPA 20 (41,75%), Orelha de onça (36,41%) e Gigante (32,59%). Para o CDAPB a melhor cultivar foi a IPA 20, com 75,2%, seguida da Orelha de onça (61,5%) e Miúda (56,1%). Quanto ao desempenho, a inclusão do farelo de palmacultivar IPA 20 na proporção de 113 g kg-1 promove os melhores valores de ganho de peso e de peso final para juvenis de tilápia nilótica.Supplying the nutritional needs of animals in an economical way is essential to the success of any type of production. The forage palm is a cactaceae well-adapted to semiarid regions and commonly used in the feeding of ruminants. However, studies assessing its use in fishes are scarce. We aimed to evaluate the digestibility of bran from five different forage palm cultivars (Opuntia fícus) in juvenile Nile tilapia and the development of juveniles when receiving increasing levels of the cultivar with the best apparent digestibility coefficient of crude protein (ADCCP) (75.2%). We used 90 masculinized juvenile Nile tilapia (with an average weight of 6.02 ± 0.65 g) in the digestibility experiment to determine the apparent digestibility coefficients of dry matter (ADCDM), crude energy (ADCCP), and crude protein of the cultivars (Orelha de onça, Miúda, Gigante, Comum, and IPA 20). The experimental design was completely randomized (CRD) with five treatments and three repetitions. In the development experiment, 300 masculinized juvenile Nile tilapia (with average weight of 1.39 ± 0.12 g) received feed with different inclusion levels (0, 72, 144, and 216 g Kg-1) of IPA 20 palm bran in a CRD with four treatments and five repetitions. We observed significant differences (P < 0.05) for ADCDM and ADCCP between the treatments. The cultivars that presented the highest ADCDM were IPA 20 (41.75%), Orelha de onça (36.41%), and Gigante (32.59%). For ADCCP, the best cultivar was IPA 20 with 75.2%, followed by Orelha de onça (61.5%), and Miúda (56.1%). As for the performance, the inclusion of IPA 20 palm bran at a rate of 113 g/kg-1 provided the best values in terms of weight gain and final weight in juvenile Nile tilapia