Elisangela Minati Gomide

Planos nutricionais com a utilização de aminoácidos e fitase para frangos de corte mantendo o conceito de proteína ideal nas dietas

This study was carried out to evaluate the performance and characteristics of carcass of broiler chickens fed diets with reduced levels of CP, available P (aP) and Ca, supplemented with phytase and amino acids. The growth phases evaluated were: Phase1, 1 - 21 days old, phase 2, 22 - 42 days old. A completely randomized design was used, with the treatments constituted of five nutritional plans (NP), with six replicates of 25 birds each. The nutritional plans were: NP1 - basal ration (21.4% CP - phase 1) + basal ration (19.3% CP - phase 2); NP2 = basal ration (phase 1) + ration with 18% CP (phase 2); NP3 = basal ration (phase 1) + ration with 16% CP (phase 2); NP4 = ration with 19% CP (phase 1) + ration with 16% CP (phase 2) and NP5 = ration with 17% CP (phase 1) + ration with 16% CP (phase 2). Except for basal ration, it was reduced the level of aP for 0.34% and 0.30% in the phases 1 an 2, respectively, and Ca to 0.80 and 0.70% in the phases 1 and 2, respectively , and in theses diets were added 500 FTU of phytase/ kg of ration. The NP4 and NP5 affected the bird performance. The bird fed NP2 and NP3 showed performance similar to those which was fed NP1, while birds that were fed PN4 and PN5 remained unchanged. The carcass and breast yield were not influenced by the nutritional plans. The birds fed basal diets in the two rearing phases (NP1) showed higher yield of thigh + drumstick. There was increase of the abdominal fat when the birds were fed NP3, 4 and 5. In conclusion, is possible to reduce the protein of the ration up to 16% in the phase 2, supplemented with phytase and amino acids, since the ration of the phase 1 be formulated with recommended nutritional levels.

Effect of ph and temperature on the activity of phytase products used in broiler nutrition

The activity of three commercial microbial phytase (Aspergillus oryzae, A. niger, and Saccharomyces cerevisae) products used in broiler nutrition was determined at different pH (2.0 to 9.0) and temperature (20 to 90°C) values. Enzymatic activity was determined according to the reaction of the phytase with its substrate (sodium phytate), in four replicates, and was expressed in units of phytase activity (FTU). A. oryzae phytase exhibited optimal activity at pH 4.0 and 40°C, but its absolute activity was the lowest of the three phytases evaluated. A. niger phytase exhibited maximal activity close to pH 5.0 and 45 o C, whereas S. cerevisae phytase presented its highest activity at pH close to 4.5 and temperatures ranging between 50 and 60°C. It was concluded that A. niger and S. cerevisae phytase products exhibited the highest absolute activities in vitro at pH and temperature values (pH lower than 5.0 and 41 o C) corresponding to the ideal physiological conditions of broilers, which would theoretically allow high hydrolysis rate of the phytate contained in the feed.

Rações com níveis reduzidos de proteína bruta, cálcio e fósforo com fitase e aminoácidos para frangos de corte

In performance and metabolism trials, diets with reduced levels of crude protein, calcium and available phosphorus on the performance, carcass characteristics, tibia ashes, balance and retention of nitrogen and phosphorus of broiler chickens in phase from 8 to 21 and 8 to 35 days were evaluated. In each phase, 30 and 25 birds per experimental unit were used in the performance assay and five and three in the metabolism assay, respectively, in a completely randomized experimental design, with six replications. Treatments consisted of diet with 21% crude protein without phytase (control), formulated with nutritional levels recommended on the Brazilian tables, and diets with 21, 20, 19 and 18% crude protein with phytase (8 to 21 days) and from 8 to 35 days, the control diet had 20% crude protein without phytase (control), and others diets with 20, 19, 18, 17% crude protein, with phytase. In the diets with phytase (80 g of Ronozyme NP(M) phytase per ton of diet), the level of available phosphorus was reduced in 0.15 and the calcium in 0.30 percentage points in relation to the control diet. No effect was observed with the reduction of nutrients on feed intake, weight gain, or feed conversion in either phase or for the study of carcass characteristics to the 35 days. However, higher abdominal fat percentage was observed when the broilers were fed diet with lower protein level. The excretion of nitrogen and phosphorus decreased when birds received diets with reduced levels of these nutrients. Ash percentage in the tibia was not influenced by treatments. It is possible to reduce protein level, available phosphorus, and calcium of the diets in up to 3, 0.15 and 0.30 percentage points when the diets are supplemented with phytase and amino acids, respectively.

Nitrogen, calcium and phosphorus balance of broilers fed diets with phytase and crystalline amino acids

Objetivou-se, com este trabalho, avaliar o efeito de racoes com reduzidos teores de proteina bruta (PB) e fosforo disponivel (Pd), suplementadas com fitase e aminoacidos, para frangos de corte na fase de crescimento (14 a 21 dias) e terminacao (35 a 42 dias de idade) sobre o balanco de nitrogenio, potassio e fosforo. Foram utilizados 90 pintos Cobb, distribuidos em um delineamento inteiramente casualizado com tres tratamentos e seis repeticoes, com cinco e tres aves por unidade experimental nas fases inicial e de crescimento, respectivamente. As racoes foram formuladas para conterem niveis reduzidos de PB e Pd (19 e 17% de PB na fase de crescimento, com 0,34% de Pd e 18 e 16% de PB na fase de terminacao, com 0,30% de Pd) e suplementadas com aminoacidos e 500 FTU de fitase/kg de racao Essas racoes foram, entao, que foram comparadas a uma racao controle (21% de PB e 0,46% de Pd para fase de crescimento e 19% de PB e 0,40% de Pd para fase de terminacao). A reducao da PB em quatro unidades percentuais reduziu a excrecao, e aumentou a retencao de nitrogenio, mostrando que a fitase nao interferiu no balanco de nitrogenio ao serem incluidos aminoacidos cristalinos nas racoes. A excrecao de potassio diminuiu em dietas com PB reduzida, mas esta reducao em excesso diminuiu a retencao deste elemento, exceto na fase de retirada. Conclui-se que racoes contendo niveis reduzidos de PB, calcio e fosforo, suplementadas com fitase e aminoacidos, sao eficientes em diminuir o poder poluente das excretas de frangos de corte.

Efeito da idade de corte na performance de três forrageiras do gênero Cynodon

O experimento foi conduzido em area do Departamento de Zootecnia da Universidade Federal de Lavras, de novembro do 2000 a maio de 2001, com o objetivo de avaliar a performance de tres cultivares do genero Cynodon em quatro idades de corte (28, 42, 56 e 70 dias) quanto ao rendimento e valor nutritivo. As cultivares estudadas foram Coastcross (Cynodon dactylon (L.) Pers. cv. Coastal x Cynodon nlemfuensis Vanderyst var. robustus), Tifton 68 (Cynodon spp) e Tifton 85 (Cynodon spp). Os tratamentos foram estabelecidos sob delineamento em blocos ao acaso, esquema de parcelas subdivididas, com cinco repeticoes; sendo as cultivares de gramineas (= tratamentos) alocadas nas parcelas e as idades de corte nas subparcelas. Observou-se que, independentemente das cultivares estudadas, a producao de MS, com o avanco do estadio de maturidade, cresceu de forma quadratica (2,15 a 11,09 t/ha), atingindo pontos maximos de producao aos 70 dias. Os teores de PB apresentaram uma correlacao negativa linear com a idade de corte, decrescendo de 17,18 a 11,04% de PB aos 28 e 70 dias de crescimento, respectivamente. Por outro lado, o teor de FDN apresentou correlacao positiva com a idade de corte, sofrendo incrementos com o avanco da idade de corte. Ja os coeficientes de DIVMS diminuiram de forma quadratica com o avanco da idade, variando de 65,11 a 51,50% aos 28 e 70 dias, respectivamente. Conclui-se que independente da cultivar de graminea, a melhor idade de corte ocorre entre 35 a 48 dias, momento em que ha um bom rendimento e valor nutritivo da forragem.

Content of plasmatic glycerol and activity of hepatic glycerol kinase in broiler chickens fed diets containing different sources and concentrations of glycerine

The objective of this study was to evaluate the effect of three sources of glycerine (crude glycerine from soya bean oil - CGSO, mixed crude glycerine from frying oil and lard--MCG, and a semipurified glycerine from soya bean oil--SPGSO) in four concentrations in the diet (17.5, 35.0, 52.5 and 70.0 g of each type of glycerine per kg of feed) on the levels of plasmatic glycerol and the activity of the hepatic enzyme glycerol kinase in broilers of 22-35 days old (experiment I) and 33-42 days old (experiment II). The highest (p < 0.05) plasmatic glycerol level was detected in broilers fed diet containing CGSO. Independent of the source, increasing the concentration of glycerine led to a linear increase (p < 0.05) in the plasmatic glycerol concentration. In experiment I, all the diets containing glycerine resulted in increased concentrations of plasmatic glycerol, in relation to the control diet without glycerine. However, in experiment II, only the diet containing 17.5 g of CGSO per kg of feed and the diets formulated with any of the three types of glycerine in the inclusion concentrations of 35, 52.5 and 70 g/kg of feed resulted in higher plasmatic glycerol levels than those observed in the control broilers. The source of glycerine influenced the glycerol kinase activity only in experiment II, where the use of CGSO in the diet increased the enzyme activity. For both experiments, the glycerol kinase activity increased with the inclusion of glycerine in the diet. In conclusion, based on the absence of saturation of the glycerol kinase activity for the three glycerine sources and for both rearing periods evaluated, the broilers can metabolize the glycerol (at the level of the phosphorylation of the glycerol to glycerol-3-phosphate in the liver) present in the glycerine when the diet is supplemented with up to 70 g of glycerine per kg of feed.

Diets with reduced levels of nutrients supplemented with phytase and amino acids for broilers

Um experimento de desempenho e outro de metabolismo foram conduzidos simultaneamente com frangos de corte de 22 a 35 dias de idade, avaliando-se cinco dietas em seis repeticoes. A dieta controle, sem fitase, continha 19% de proteina bruta (PB); 0,412% de fosforo disponivel (Pdisp) e 0,824% de calcio (Ca). As demais dietas foram suplementadas com fitase e formuladas com 0,262% de Pdisp e 0,524% de Ca, tendo o teor de PB variado em 19 ate 16%. No ensaio de desempenho, 750 aves foram utilizadas, avaliando-se o desempenho, o teor de cinzas na tibia e rendimentos de carcaca, cortes e gordura abdominal, aos 35 dias de idade. O ensaio de metabolismo foi realizado com 90 aves, determinando-se a energia metabolizavel aparente, corrigida pelo balanco de nitrogenio e o coeficiente de metabolizabilidade da materia seca (CMMS) das racoes, e tambem o balanco e retencao de nitrogenio (N) e fosforo (P). As dietas nao influenciaram o desempenho, teor de cinzas na tibia e os rendimentos de carcaca, peito e coxa + sobrecoxa. Entretanto, as aves alimentadas com a racao contendo 16% de PB apresentaram maior teor de gordura abdominal. As racoes com 19% de PB apresentaram menor valor energetico e CMMS. A retencao de N e P foi maior nas aves que receberam as racoes com reduzidos teores de PB e fitase. Portanto, quando a racao de frangos de corte e suplementada com fitase e aminoacidos e possivel reduzir a PB, Pdip e Ca em ate 16; 0,262 e 0,524%, respectivamente.

Níveis de cálcio e fósforo disponível em rações com fitase para frangos de corte nas fases pré-inicial e inicial

Two independent experiments, one in pre-starter phase (1 to 7 days) and the other in the starter phase (8 to 21 days of age), were carried out with broilers to evaluate levels of calcium and available phosphorus (aP) in diets supplemented with 500 units of phytase activity/kg of diet. Each experiment consisted of a performance and a metabolic assay, and was conducted in a factorial schedule (3 × 4) + 1, with three aP levels (0.42, 0.37, 0.32% in the pre-starter phase and 0.39, 0.34, 0.29% in the starter phase), four calcium levels (0.94, 0.84, 0.74, 0.64% in the pre-starter phase and 0.88; 0.78, 0.68, 0.58% in the starter phase) plus a control diet. The control corresponded to the only diet without phytase and contained 0.47% of aP and 0.94% of calcium (pre-starter phase) or 0.44% of aP and 0.88% of calcium (starter phase). In the performance assays, at 7 and 21 days of age the feed intake, weight gain, feed conversion and the ash content in the tibia were evaluated. In the metabolic assays the apparent metabolizable energy corrected for nitrogen balance (AMEn) of the feed, and dry matter digestibility coefficients (DMDC) were determined. Calcium levels influenced the feed intake, AMEn and DMDC in the prestarter phase, and in the starter phase they influenced bone ash, AMEn and DMDC. The aP levels influenced the content of tibia ash, AMEn and DMDC in the pre-starter phase, and bone ash and DMDC in the starter phase. By adding 500 units of phytase activity/kg of diet, it is possible to reduce, respectively, the calcium and aP levels to 0.64% and 0.37% in the prestarter phase, and to 0.58% and 0.29% in the starter phase, since this reduction does not cause a negative effect on performance or bone mineralization of broilers in the evaluated periods.Dois experimentos independentes, um na fase pre-inicial (1 a 7 dias) e outro na fase inicial (8 a 21 dias de idade), foram realizados com frangos de corte para avaliar niveis de calcio e fosforo disponivel (Pdisp) em racoes suplementadas com 500 unidades de atividade de fitase/kg de racao. Cada experimento constou de um ensaio de desempenho e outro de metabolismo e foi conduzido em esquema fatorial (3 × 4) + 1, sendo tres niveis de Pdisp (0,42; 0,37; 0,32% na fase pre-inicial e 0,39; 0,34; 0,29% na fase inicial), quatro niveis de calcio (0,94; 0,84; 0,74; 0,64% na fase pre-inicial e 0,88; 0,78; 0,68; 0,58% na fase inicial) mais uma racao controle. O controle correspondeu a unica racao sem fitase e continha 0,47% de Pdisp e 0,94% de calcio (fase pre-inicial) ou 0,44% de Pdisp e 0,88% de calcio (fase inicial). Nos ensaios de desempenho, aos 7 e aos 21 dias de idade, foram avaliados o consumo de racao, o ganho de peso, a conversao alimentar e o teor de cinzas na tibia. Nos ensaios de metabolismo, determinaram-se a energia metabolizavel aparente corrigida pelo balanco de nitrogenio (EMAn) das racoes e os coeficientes de digestibilidade da materia seca (CMMS). Na fase pre-inicial, os niveis de calcio influenciaram o consumo de racao, a EMAn e o CMMS e, na fase inicial, afetaram o conteudo de cinzas osseas, a EMAn e o CMMS. Os niveis de Pdisp influenciaram o teor de cinzas na tibia, a EMAn e o CMMS na fase pre-inicial e as cinzas osseas e o CMMS na fase inicial. Adicionando 500 unidades de atividade de fitase/kg de racao, e possivel reduzir, respectivamente, os niveis de calcio e Pdisp para 0,64% e 0,37% na fase pre-inicial e 0,58% e 0,29% na fase inicial, pois essa reducao nao tem efeito negativo sobre o desempenho e a mineralizacao ossea dos frangos de corte nessas fases.

Reduction in the protein level and addition of oil in diets for finishing pugs under different temperatures

The objective of this study was to evaluate the effect of reducing the crude protein (CP) with the use of amino acids in diets with the same amount of calories anddifferent levels of soybean oil (SO) for finishing pigs kept in two different ambient temperatures. A total of 120 barrows (initial weight of 68.0±1.9 kg) were utilized for the experiment. The design was of randomized blocks in a 2 × 3 × 2 factorial arrangement (two levels of CP, 16.2 and 13.7%; three levels of SO, 1.5; 3.0 and 4.5%; and two ambient temperatures, 19 and 31 oC), totaling twelve treatments with five replicates for thirty days. The heat reduced feed intake (FI) of the animals, regardless of the levels of CP and SO used, and reduced weight gain (WG) in diets with reduced CP and SO or higher SO. The increased level of CP and SO improved feed conversion (FC) when the animals were kept in thermoneutral environment and given a diet with higher protein content. The reduction in CP increased FI only in the thermoneutral environment. In the heat, WG increased in diets with higher levels of SO, without influencing FC. The manipulation of diet and temperature did not affect most carcass traits. The SO reduced backfat thickness (BT) only in diets with high CP and animals kept in thermoneutral environment. The reduction of CP increased the BT only in diets with high content of SO, both in hot and thermoneutral environments. Heat reduces FI and the inclusion of SO does not improve performance or carcass characteristics in these conditions. The reduction in CP improves WG only in diets with high oil content; however, it increases BT. In thermoneutral environment, increasing the SO is beneficial for performance and carcass characteristics, except when diets with reduced CP are used. The reduction in CP improves performance only in diets with low oil content.

Activity of fungal phytases stored in two ways in response to the period of storage at room temperature

Two distinct experiments were conducted simultaneously with phytases of Aspergillus oryzae and A. niger for determining enzyme activity in response to storage period (up to 180 days at room temperature - RT). In the first experiment, enzymes were stored as they were acquired (pure form) and the activity was measured periodically during 180 days of storage at RT. In the second experiment, the phytases were incorporated to a supplement containing vitamins, minerals, and amino acids; and then this supplement was stored at RT up to 180 days, so that every 30 days of storage was collected one aliquot from each replicate for determining enzymatic activity. In conclusion, the phytase activity is affected by storage duration. To ensure 80% of the initial activity, the phytases of A. oryzae and A. niger can be stored in the pure forms for up to 53 and 135 days at RT, respectively. However, if the phytases of A. oryzae and A. niger are incorporated to a supplement containing vitamins, minerals, and amino acids then the storage period at RT should not exceed 67 and 77 days, respectively.