ABSTRACT The objective of this paper was to investigate the availability of betaine present in fine wheat bran (FWB) in diets for growing pigs. We used thirty crossbred intact males, housed individually in metabolic cages and distributed in a randomized block design, with five treatments and six replicates. Blocks consisted of two periods of 15 days. Average initial body weights were 32.00±1.30 and 44.90±1.32 kg, in the first and second periods, respectively. Treatments were modified only at the level of methionine plus cysteine (Met+Cys) required and the Met+Cys sources, consisting of a negative control (NC), formulated with 80% of Met+Cys requirements, and four positive controls (PC): PCMet - NC supplemented with 1.2 g kg−1 of DL-methionine; PCBet - NC supplemented with 0.9 g kg−1 of anhydrous betaine; PCFWB - diet formulated with FWB; and PCFWB+Met - PCFWB supplemented with 1.0 g kg−1 of DL-methionine. No differences were observed on performance-related variables or on the digestibility coefficient of dry matter. Conversely, the digestibility coefficient of crude energy was lower when pigs were fed FWB and could be associated to the higher fiber content of FWB feeds. Digestible energy of feeds was higher for FWB diets, while the metabolizable energy of FWB diets did not differ from PCMet and PCBet. Nitrogen intake and apparent absorption were lower when pigs were fed FWB, but nitrogen retention, protein utilization, and biological value of the feed protein were the same among PC treatments, indicating that nitrogen from diets was used by pigs with the same efficiency, and is supported by no differences in performance-related variables. The FWB composition showed 12 g of betaine kg−1, which is available to maintain nitrogen retention and performance.

O objetivo do presente trabalho foi avaliar o valor nutricional e energético de subprodutos do arroz, na presença ou não de fitase, para suínos em crescimento. Foram utilizados 36 suínos machos, castrados, alojados em gaiolas metabólicas individuais. Realizou-se a coleta total de fezes e urina em dois períodos de dez dias: cinco de adaptação e cinco de coleta. Utilizou-se o delineamento de blocos ao acaso, tendo-se considerado o período de coleta como bloco, com cinco tratamentos e sete repetições. Duas dietas controle (com e sem fitase - Fit) foram utilizadas nos cálculos de digestibilidade, a última para avaliar a influência da enzima na digestibilidade da energia dos ingredientes teste. A dieta controle foi substituída em 30% pelos subprodutos testados: farelo de arroz desengordurado (FAD) com ou sem Fit e farelo de arroz desengordurado desfitinizado (FADD). O uso de fitase na dieta controle não influenciou na digestibilidade da energia do FAD+Fit. Comparado ao FAD+Fit, o farelo de arroz desengordurado desfitinizado apresentou mais EM e proteína digestível, mas menos P e Ca digestíveis. A suplementação de fitase melhorou a utilização do P e Ca do FAD e aumentou a digestibilidade da energia e da proteína. O FAD sem fitase apresentou os menores coeficientes de digestibilidade para todas as respostas. Energia metabolizável, proteína, fósforo e cálcio digestíveis do FAD, FAD+Fit e FADD foram, respectivamente, 2.140; 2.288 e 2.519kcal kg-1; 79,25; 92,41 e 107,10g kg-1; 1,62; 3,41 e 2,11g kg-1 e 2,80; 3,79 e 2,90g kg-1.

The objective of this study was to evaluate nutritional and energetic value of rice by-products, with or without phytase, using growing pigs. Thirty-six male pigs were housed in individual metabolic cages. Total collection of feces and urine was carried out in two periods of ten days: five days for adaptation and five days for collection. A randomized blocks design was used, considering the sampling period as a block, with five treatments and seven replicates. Two control diets (with and without phytase - Phy) were used in the digestibility calculations, the latter in order to evaluate the enzyme influence on energy digestibility of the tested ingredients. The control diet was replaced by 30% of one of the ingredients: defatted rice bran (DRB) with and without Phy and dephytinised defatted rice bran (DDRB). The use of Phy in the control diet did not influence DRB+Phy energy digestibility. Relative to DRB+Phy, dephytinised defatted rice bran had higher contents of ME and digestible protein but lower digestible P and Ca. Phy supplementation increased Ca and P utilization of DRB and improved energy and protein digestibility. The DRB without Phy showed the lowest digestibility coefficients for all responses. Metabolizable energy, digestible protein, phosphorus and calcium of DRB, DRB+Phy and DDRB were respectively, 2140, 2288 and 2519kcal kg-1; 79.25, 92.41 and 107.10g kg-1; 1.62, 3.41, and 2.11g kg-1 and 2.80, 3.79 and 2.90g kg-1.

O objetivo deste trabalho foi avaliar o valor nutricional e energético de subprodutos do trigo, em dietas para suínos em crescimento, e obter equações de predição da energia metabolizável. Foram utilizados 36 suínos machos, castrados, alojados em gaiolas metabólicas individuais. Realizou-se a coleta total de fezes e urina em dois períodos de dez dias: cinco para adaptação e cinco para coleta. Utilizou-se o delineamento de blocos ao acaso, tendo-se considerado o período de coleta como bloco, com seis tratamentos e seis repetições. A dieta referência foi substituída em 30% por um dos subprodutos testados: farinheta, farelo fino, farelo de trigo, farelo grosso e farelo grosso moído; este último usado para avaliar a influência da granulometria na digestibilidade. A fibra bruta foi a variável que proporcionou a melhor estimativa da energia metabolizável. O farelo fino foi superior em energia digestível e metabolizável, em comparação ao farelo grosso moído. O farelo grosso moído apresentou os menores coeficientes de digestibilidade, e a diminuição de seu diâmetro geométrico médio não aumentou a digestibilidade dos nutrientes e da energia. Entre os subprodutos avaliados, a farinheta apresenta maior energia digestível, energia metabolizável e proteína digestível, o que mostra elevado potencial para utilização em dietas para suínos em crescimento.

The objective of this work was to evaluate nutritional and energy values of wheat by‑products in diets for growing pigs, and to obtain prediction equations for metabolizable energy. Thirty‑six male pigs were housed in individual metabolic cages. Total collection of feces and urine was carried out in two periods of ten days: five days for adaptation and five days for collection. A randomized complete block design was used, considering the sampling period as a block, with six treatments and six replicates. The reference diet was replaced by 30% of one of the tested by‑products: wheat middlings, fine wheat bran, common wheat bran, coarse wheat bran, and ground coarse wheat bran; the latter was used to evaluate the influence of particle size on digestibility. Crude fiber was the variable that provided the best estimate of metabolizable energy. Fine wheat bran was superior in terms of digestible and metabolizable energy, when compared to coarse wheat bran. Ground coarse wheat bran showed lower digestibility coefficients, and the reduction in its average geometric diameter did not increase nutrient availability. Among the evaluated by‑products, wheat middlings have higher digestible energy, metabolizable energy, and digestible protein, showing high potential use in diets for growing pigs.