ABSTRACT: This study was designed to simulate productive and economic losses due to the withdrawal of antibiotic growth promoters (AGP) from pig diets. Articles that compared diets with AGP (AGP+) or without AGP (AGP–) for pigs were collected from electronic databases and the performance results were entered in a database. A meta-analysis was performed following the sequence: graphical analysis, correlation, and variance-covariance. The performance results observed in the meta-analysis, feed cost, and AGP costs were used to build equations to estimate the economic effect of withdrawing AGP. The database comprised 81 scientific articles containing 103 experiments totalizing 42,923 pigs. Avilamycin (24.7 %) was the most frequent AGP in the database, followed by Colistin (15.4 %), Tiamulin (11.7 %), Tylosin (8.0 %), Lincomycin (9.4 %), and Bacitracin (5.4 %). Weight gain (p < 0.05) increased in AGP+ diets during post-weaning (6.5 %). However, there was no effect of AGP on weight gain of growing-finishing pigs. There was better (p < 0.05) feed conversion in pigs fed AGP+ diets in all rearing phases. Weight gain and feed conversion improved (p < 0.05) with the addition of Avilamycin, Bacitracin, and Tylosin. AGP withdrawal in the post-weaning phase increased feed costs by US$ 0.86 per animal and in growing-finishing phase the increase was US$ 3.11. Thus, pigs fed AGP+ diets have a better performance than pigs fed AGP- diets and the withdrawal of AGP increases feed costs.

ABSTRACT. The aim of this study was to evaluate the effect of conjugated linoleic acid (CLA) supplementation in diets with different energy levels in broiler performance. Birds were offered a starter (1-21 d), grower (22-35 d) and finisher (36-42 d) diets; wherein soybean oil was replaced by CLA. The study consisted of a 3 × 2 factorial arrangement with two CLA levels (0 and 1%) and three energy levels (3050, 3100 and 3150 ME kg-1 diet). During the grower and finisher periods, birds were fed diets with same energy level and CLA supplementation was maintained the same. Growth performance was assessed weekly, and carcass and cuts yield were assessed at 42d. Interaction effect of CLA by energy level was observed in broiler performance and carcass yield throughout the study (p > 0.05). During the overall period (1-42 d) broiler performance was not affected by CLA (p > 0.05).However, CLA supplementation (1%) decreased weight gain (p < 0.05) at 21d, regardless of energy level, with no effects on feed intake and feed conversation rate (p > 0.05). The increase in dietary energy was not able to compensate the negative effect on growth performance of broilers supplemented with 1% CLA at the starter period.

ABSTRACT: The effects of mycotoxins on the productive performance of growing pigs and broilers were evaluated using meta-analytical approach. Two databases were constructed: (1) Broilers, with information collected from 51,497 birds and published in 158 scientific papers from 1980 to 2016; and (2) Pigs, with information collected from 7,743 animals and published in 72 scientific papers from 1980 to 2015. The meta-analyses were performed independently for each specie, following three sequential analyses: graphical, correlation, and variance-covariance. Broilers and pigs challenged by mycotoxins reduced (p < 0.05) feed intake by 9 and 6 %, weight gain by 15 and 11 %, and feed efficiency by 6 and 4 % compared with non-challenged animals, respectively. Aflatoxins were the most studied mycotoxins in both databases. Birds and pigs challenged by aflatoxins reduced (p < 0.05) feed intake by 10 and 8 %, growth by 15 and 11 %, and feed efficiency by 6 and 7 % compared to non-challenged animals, respectively. In both databases, variation on growth performance due to mycotoxins showed a linear relationship (p < 0.05) with the feed intake variation caused by the challenge. The intercepts of the regression-based equations were different from zero and negative, which may indicate that mycotoxins altered the maintenance requirements in challenged animals. In conclusion, both broilers and growing pigs show losses in performance responses and worse nutritional efficiency when challenged by mycotoxins.

ABSTRACT We evaluated the effects of a protease supplementation on the growth performance and intestinal health of broilers. Cobb chicks (392; 1-42 d) were divided into four treatments (seven replicates of 14 birds each). There were two feed formulations: a standard diet (SD) and a low crude protein and digestible amino acids diet (Low CP&AA). The two diets were either supplemented (+P) or not (−P) with a protease (Jefo Protease; 1.25 g kg−1). Performance was evaluated by feeding phases (1-7, 8-21, 21-35, and 35-42 d). On day 28, ileum samples were analyzed by a morphometric index for histological alterations (I See Inside Scoring System – ISI). Broilers fed the Low CP&AA had a poor feed conversion ratio (FCR); however, the addition of the protease to the Low CP&AA positively affected FCR and body weight gain and promoted a performance similar to the group fed SD−P. Birds fed diets supplemented with the protease presented the best ISI morphological index, mainly as a result of the low number of alterations regarding the lamina propria, epithelial thickness, and enterocyte proliferation. It is possible to conclude that the enzyme improves feed conversion and lamina propria, epithelial thickness, and proliferation of enterocytes index of broiler chickens when added to a standard diet or with a low crude protein and digestible amino acids diet.

ABSTRACT The present study evaluated the effect of variation in the amount of total dietary fiber (TDF) in sow diets, provided from 74 to 114 days of gestation, on the digestibility of nutrients and energy during gestation, as well as productivity and metabolism during gestation and lactation. Thirty-three sows were used in a randomized experimental design. The amounts of TDF in three treatment diets were 156, 223, and 282 g kg−1. The daily intake of nutrients and energy was similar for all diets the entire period of gestation, differing only in the volume of ration consumed, which was 2.1, 2.2, and 2.4 kg day−1 (days 74 to 90) and 2.5, 2.6, and 2.8 kg day−1 (days 91 to 111) for the 156, 223, and 282 g kg−1 TDF diets, respectively. During gestation, the increase in TDF resulted in a significant linear decrease in the digestible energy and apparent total tract digestibility of dry matter, gross energy, crude protein, non-fibrous carbohydrates, and organic matter. During gestation, blood concentrations of protein and globulins exhibited a quadratic response to the amount of TDF in the diet, whereas cholesterol exhibited a significant linear increase. The productivity and reproductive performance of the sows during gestation and lactation or the birth weight of the piglets were not affected by the amount of TDF, but the average daily weight gain of the litter during nursing increased linearly with increasing levels of dietary fiber. Increasing the amount of TDF reduces the digestibility of nutrients and energy, without affecting the performance of the sows during gestation and lactation or that of the piglets at birth and increasing TDF during gestation improves the weight gain of piglets during lactation.

Resumo Dois experimentos foram conduzidos para avaliar a bioequivalência de uma fonte comercial de fosfatidilcolina (Biocholine®) como alternativa ao cloreto de colina e as exigências de colina de frangos de rápido desempenho. No Experimento I, 672 frangos foram alimentados com quatro níveis de Biocholine® (0, 100, 200 ou 300 mg/kg) e três níveis de colina (200, 400 ou 600 mg/kg) supridas pelo cloreto de colina entre 4 e 28 dias de idade. No Experimento II, 462 frangos receberam dietas suplementadas com 0, 200, 400, 600 ou 800 mg/kg de colina através do cloreto de colina. Em ambos os experimentos, as dietas foram à base de arroz branco, farelo de soja e glúten de milho. No Experimento I, as aves alimentadas com cloreto de colina apresentaram maior consumo de ração em relação àquelas alimentadas com Biocholine®. Ambas as fontes de colina melhoraram linearmente a conversão alimentar entre 15 e 28 dias, mas as curvas apresentaram diferentes inclinações, mostrando que uma unidade de Biocholine® foi equivalente a 2,52 unidades de colina suprida na forma de cloreto de colina. No Experimento II, a suplementação de colina apresentou efeito quadrático sobre o ganho de peso sem afetar a conversão alimentar. As exigências de colina para ganho de peso foram 778, 632 e 645 mg/kg para as fases de 1-7, 1-35 e 1-42 dias de idade, respectivamente.

Abstract Two experiments were carried out to evaluate the bioequivalence of a commercial phosphatidylcholine source (Biocholine™) as an alternative to choline chloride and the choline requirements of broilers of a fast-growth strain. In Experiment I, 672 broilers were fed four Biocholine™ levels (0, 100, 200, or 300 mg/kg) and three choline levels (200, 400, or 600 mg/kg) supplied as choline chloride between 4 and 28 days (d) of age. In Experiment II, 462 broilers received diets supplemented with 0, 200, 400, 600 or 800 mg/kg choline as choline chloride. In both experiments, diets were based on white rice, soybean meal, and corn gluten. In Experiment I, birds fed choline chloride presented higher feed intake than those fed Biocholine™. Both choline supplements linearly improved feed conversion ratio (FCR) between 15 and 28 d, but the curves presented different slopes, showing that one unit (U) of Biocholine™ was equivalent to 2.52 U of choline supplied as choline chloride. In Experiment II, the supplementation of choline had a quadratic effect on weight gain (WG) but did not affect FCR. Choline requirements for WG were determined as 778, 632, and 645 mg/kg for 1-7, 1-35, and 1-42 d of age, respectively.

ABSTRACT This study was conducted to evaluate the effects of dietary metabolisable energy (ME: 3.25, 3.40, 3.55, or 3.70 Mcal kg−1) and weaning weight (WW: light 4.0±0.7 kg, and heavy: 6.3±0.6 kg) on productive response and energy utilization of weaned piglets. Sixty-four male piglets were housed in 32 metabolic cages (two animals per cage) during the first 14 d postweaning. At day 15, only one animal per cage was kept until day 28. Body composition, energy, and nutrient deposition rates and energy utilization efficiency were measured through a comparative slaughter procedure. Piglets with light WW had a poorer feed conversion ratio and lower weight gain and feed intake when expressed per live weight. Increased ME led to greater daily fat deposition in the empty bodies (defined as weighted mean of the carcass + organs + blood, no intestinal content), while light WW piglets had a reduced protein deposition. Light WW piglets increased heat production with increased ME, but no effect was seen for the heavy WW piglets. By contrast, heavy WW piglets increased empty body gross energy as ME increased, while no influence was observed on light WW piglets. Increasing dietary energy levels did not contribute to the subsequent growth performance of piglets that were lighter at weaning. The lack of interaction between weaning weight and dietary ME content on growth performance does not support the hypothesis that light piglets at weaning do not exhibit compensatory growth because of limitations in energy intake.

ABSTRACT An experiment was performed to evaluate the effect of the incubation system ― multiple-stage (MS) and single-stage (SS) ― on the characteristics at hatching, intestinal morphology, metabolism, and performance of Cobb-500 chickens from 1 to 40 d of age. A total of 1,968 fertile eggs were incubated in two setters under commercial conditions. Birds hatched in SS were longer than those hatched in MS, and the females had higher relative intestinal weight compared with males. However, at hatching, there were no differences in BW and yolk-free body mass from incubation system or sex. In the period from 1-40 d, the birds hatched in SS were heavier, had higher weight gain and better adjusted feed conversion, without differences in feed intake and feed conversion. This result is due mainly to MS females, which always, although in some periods only numerically, exhibited worse responses than the other treatment, lowering the average MS bird performance. Sex influenced the duodenal villi height in chickens at 0 d; females showed larger villi than males. Moreover, the birds hatched in SS had deeper crypts than those hatched in MS. At 7 d, because males had higher feed intake, the differences in duodenal villi height found at hatching disappeared, leaving only a gender effect on jejunum crypt depth: females showed deeper crypts. As regards the metabolism coefficients of nutrients from 5 to 7 d, females were more efficient in metabolizing energy and showed higher apparent metabolizable energy corrected for nitrogen values than males, with no differences caused by the incubation system. The best incubation conditions are obtained with the single-stage system, based on the improved broiler performance (2.98%), especially in the females (5.04%).

ABSTRACT In similar conditions of food handling and genetics, there are large differences in the final productivity of farms, resulting from inherent factors of the production system. This fact predisposes the need of studies on optimizing the rearing conditions of the farms, in order to verify the main limitations for the producers. Therefore, the present study aims to generate predictions of the swine productivity in the finishing phase, using variables related to their profiles and the production results achieved. 107 farmers belonging to a swine cooperative were considered in the study, located in 47 counties at the Taquari valley region, Brazil. Predictions were generated through the aid of neural networks, and the findings show that Artificial Neural Networks (ANN) can predict the productivity variables Feed Conversion, Mortality and Average Daily Gain for the proposed case.

RESUMO Estudou-se a via de fornecimento de cloreto de sódio (NaCl) – água ou ração – sobre o desempenho de frangos de corte, consumo de água, desenvolvimento dos órgãos, metabolizabilidade da matéria seca (MMS), retenção de nitrogênio (RN), energia metabolizável aparente corrigida para nitrogênio (EMAn), matéria seca das excretas (MSex) e composição de carcaça. Foram utilizados 120 frangos da linhagem Ross 308, distribuídos em três tratamentos com quatro repetições de 10 aves cada, num delineamento completamente casualizado. De um a sete dias de idade foram submetidos a três formas de suplementação de NaCl (0,47% de Na): 100% na ração; 50% na ração e 50% na água (50% ração:50% água); e 100% na água. Durante o período de oito a 21 dias as aves receberam uma dieta única, com NaCl via ração. De um a sete dias não houve diferença no Consumo de Água, Consumo de Ração e Ganho de Peso; porém, NaCl via água proporcionou melhor CA do que por ambas as vias (p < 0,07). Aos 21 dias de idade não foram observadas diferenças significativas no desempenho, no peso relativo do coração, fígado e moela e no comprimento relativo do intestino. Não houve resposta à via de fornecimento para EMAn e MSex em pintos de quatro a sete dias de idade; no entanto, as aves que receberam o NaCl via água de bebida, exibiram menor MMS e RN (p < 0,05) no mesmo período. Conclui-se que o NaCl pode ser adicionado tanto na ração quanto na água, sem ocasionar prejuízos ao desempenho produtivo dos frangos de corte na fase pré-inicial.

SUMMARY It was investigated the way to provide NaCl -by water or feed- on performance, water intake, organs development, dry matter metabolizability (DMM), nitrogen retention (NR), apparent metabolizable energy corrected for nitrogen (AMEn), dry matter of excreta (DMEx) and carcass composition (CC) of broilers. One hundred twenty one-day-old male Ross 308 distributed in three treatments with four replications of ten birds each, in a completely randomized design, were subjected to three ways to supply NaCl (0.47% of Na): 100% in diet, 50% in diet and 50% in water (50:50), and 100% in water during the pre-starter period (one to seven days). During the starter period (eight to 21 days) the birds received a unique diet, with NaCl in diet. From one to seven days, there were no significant differences on water intake, feed intake and weight gain; but NaCl in water provided better feed conversion than in both ways (p < 0.07). At 21 d, there were no significant differences in performance, relative weight of heart, liver and gizzard, and relative length of intestine. There was no response to supply way for AMEn and DMEx in chicks from four to seven days; however, birds receiving NaCl via drinking water, exhibited lesser DMM and NR (P < 0.05) in the same period. It was concluded that NaCl can be added in both feed and water to pre-starter chicks.

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.

Trata-se de um estudo de metabolizabilidade em frangos de corte Cobb, para testar os benefícios do processamento térmico por infravermelho no farelo de arroz integral (FAI) em diferentes tempos (0, 6, 8 e 10min). O experimento foi realizado através do método de substituição, em que 20% de uma dieta referência (DR) a base de milho e farelo de soja foi substituída pelos FAIs processados em diferentes tempos. Usou-se um delineamento experimental completamente casualizado com 5 tratamentos e 10 repetições de uma ave. Entre 21 e 28 dias de idade das aves, foi feita a coleta total de excretas, com 4 dias de adaptação às dietas e 3 de coleta. A dieta com FAI 6min teve melhor aproveitamento em relação às demais e foi a única que não piorou os coeficientes de metabolizabilidade em relação à DR. Na comparação da metabolizabilidade dos ingredientes isolados, não houve diferenças estatísticas. Porém, conforme aumentou o tempo de processamento, diminuiu a solubilidade e a metabolizabilidade da proteína. O processamento térmico por infravermelho não foi capaz de melhorar a metabolizabilidade do FAI para frangos de corte.

This is a study of metabolizability in broilers Cobb, to test rice bran infrared (RB) thermal processed at different times (0, 6, 8 and 10min). It was used a reference diet (RD) based on corn and soybean in which 20% of RB was included. The experiment design was completely randomized, with 5 treatments and 10 replicates. Each replicate was a 21 day old bird. After 4 days of diet adaptation, total excreta was collected, during 3 subsequent days. Diet with RB processed at 6 was better used than the others, the only one that did not differ from RD. Comparing RB processing times, there were no significant difference between them, regarding digestibility. Processing time was negatively related to protein solubility and protein metabolizability. Infrared heat processing was not able to improve FAI metabolizability for broilers.

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.

Estudou-se o uso do ácido butírico (AB) e da fitase em dietas de suínos na fase de crescimento, variando no nível de cálcio. O experimento foi subdivido no tempo em dois períodos de 17 dias, sendo três de adaptação e 14 de mensurações. Em cada período, foram utilizados 16 suínos machos castrados, com peso de 24,6±0,7kg no primeiro e 43,2±1,77kg no segundo período. As dietas diferiam no nível de cálcio (0,5 ou 0,72%), de AB (0 ou 0,3% de butirato de sódio 84%) e de fitase (0 ou 500 FTU kg-1, fitase de origem bacteriana derivada de Escherichia coli). O delineamento foi em blocos casualizados (períodos), em decomposição fatorial 2x2x2, com quatro repetições. Foram avaliadas a digestibilidade aparente dos nutrientes e da energia bruta e o balanço de Ca e P. O AB melhorou a digestibilidade da proteína bruta, mas, de forma individual ou em combinação com a fitase, não aumentou a retenção de minerais. A fitase aumentou a retenção de P, reduzindo sua excreção fecal e urinária. O menor nível de Ca na dieta proporcionou maior retenção de Ca e menor retenção de P, em decorrência do aumento da excreção de P na urina (P<0,0001). Apesar de ter melhorado a digestibilidade protéica, o AB não aumentou a retenção de minerais, nem teve efeito aditivo ao uso de fitase, enquanto que a fitase apresentou efeito positivo para retenção de P.

It was studied the use of butyric acid (BA) and phytase in growing pigs diets, varying calcium level. The experiment was divided into two periods of time, of 17 days, with 3 days of adaptation and 14 of measurements. In each period, it was used 16 barrows weighing 24.6±0.7kg in the first and 43.2±1.77kg in the second. Diets were different in calcium level (0.5 or 0.72%), AB (0 or 0.3% sodium butyrate 84%) and phytase (0 or 500FTU kg-1 phytase of bacterial origin derived from Escherichia coli). The experimental design was in randomized blocks (periods), decomposed in 2x2x2 factorial, with four replications. It was evaluated the apparent digestibility of nutrients, gross energy and balance of Ca and P. AB improved crude protein digestibility, but individually or in combination with phytase did not increase minerals retention. Phytase increased P retention by reducing urinary and fecal excretion. The lowest diet calcium level provided higher Ca retention and lower P retention as a result of increased P excretion in urine (P<0.0001). Despite improving protein digestibility, AB did not increase mineral retention and didn't have an additive effect with the use of phytase, while phytase had positive effect on retention of P.

O objetivo deste trabalho foi comparar o método de substituição com o de análise de regressão, na determinação do valor nutricional do farelo de arroz desengordurado, em dietas para suínos, nas fases de crescimento e terminação. Foram conduzidos dois ensaios de digestibilidade com 16 suínos machos castrados na fase de crescimento, com peso vivo inicial de 50,0±3,1 kg, e 16 suínos machos castrados na fase de terminação, com peso vivo inicial de 95,0±3,8 kg, alojados em gaiolas metabólicas. Utilizou-se o delineamento inteiramente casualizado com quatro tratamentos - 0, 15, 30 e 45% de substituição da dieta-referência por farelo de arroz desengordurado - e quatro repetições, com um animal como unidade experimental. A análise de regressão foi mais precisa para estimar o valor nutricional do farelo de arroz desengordurado do que o método de substituição. Por esta análise, os coeficientes de digestibilidade aparente da matéria seca, matéria orgânica, proteína bruta e o valor de energia metabolizável do farelo de arroz desengordurado foram, respectivamente: 57,7, 64,8, 56,6% e 2.429 kcal kg-1, na fase de crescimento, e 57,7, 64,7, 62,6% e 2.233 kcal kg-1, na fase de terminação.

The objective of this work was to compare the substitution method and the regression analysis method to determine the nutritional value of defatted rice bran in diets for swines at growing and finishing phases. Two digestibility bioassays were carried out with 16 barrows with initial body weight of 50.0±3.1 kg, in the growing phase, and 16 barrows with initial body weight of 95.0±3.8 kg, in the finishing phase, housed in metabolic cages. A completely randomized design was used with four treatments - 0, 15, 30 and 45% of substitution of the reference diet by defatted rice bran - and four replications, with one animal as the experimental unit. The regression analysis was more accurate than the method of substitution to assess the nutritional value of defatted rice bran. Throught this analyse, the apparent digestibility coefficients of dry matter, organic matter, crude protein and metabolizable energy of defatted rice bran were, respectively, 57.7, 64.8, 56.6% and 2,429 kcal kg-1 on growing phase, and 57.7, 64.7, 62.6% and 2,233 kcal kg-1 on finishing phase.