RESUMO: O objetivo foi avaliar o efeito dos níveis de fertilização nitrogenada na produtividade e no valor nutritivo do BRS Kurumi quando manejado em diferentes alturas de resíduos durante os períodos seco e chuvoso do ano. O capim foi manejado em três alturas de resíduos (20, 35 e 50 cm) em associação com três níveis de fertilização com nitrogênio (0, 100 e 200 kg N/ha/ ano), durante o período seco e chuvoso do ano. Quando a altura do capim de cada parcela atingiu 80 cm, o Kurumi foi cortado nas alturas de resíduos pré-estabelecidas. Cerca de 89% da produção de MS foi observada durante o período chuvoso. A altura do resíduo de 35 cm juntamente com doses de 100 ou 200 kg N/ha/ ano, e a altura do resíduo de 20 cm, com dose de 100 kg N/ha/ ano foram os tratamentos que apresentaram maior produção de MS durante o período chuvoso. Não foram observadas diferenças na produção de MS entre os tratamentos testados durante o período da seca. O Kurumi cultivado no período da seca apresentou maior teor de fibra em detergente neutro e menor digestibilidade. O Kurumi manejado com alturas de resíduo de 20 e 35 cm e fertilizado com 100 kg N/ha apresentou os maiores valores de eficiência de utilização do nitrogênio aplicado. Recomenda-se a utilização de 20 ou 35 cm de altura do resíduo e 100 kg de N/ha/ ano para obter maior produção de biomassa e nutrientes, qualidade nutricional e eficiência no uso do nitrogênio.

ABSTRACT: The objective was to evaluate the effect of nitrogen fertilization levels on productivity, and nutritional value of BRS Kurumi managed at different residue heights during rainy and dry periods of the year. The pasture was managed in three residue heights (20, 35, and 50 cm) and three nitrogen fertilization levels (0, 100, and 200 kg N/ha/year) during the rainy and dry seasons. When the height of the grass of each plot reached 80 cm, the Kurumi was cut manually at the pre-established residue heights. Around 89% of the dry matter (DM) production was observed during the rainy season. The residue height of 35 cm together with doses of 100 or 200 kg N/ha/year, and the residue height of 20 cm, with a dose of 100 kg N/ha/year were the treatments that had the highest DM production during the rainy period. No differences in DM production were observed between tested treatments during the dry period. The Kurumi cultivated during the dry period had the highest content of neutral detergent fiber and lowest digestibility. The Kurumi managed with residue heights of 20 and 35 cm and fertilized with 100 kg N/ha had the highest values of efficiency of utilization applied nitrogen. The use of 20 or 35 cm of residue height and 100 kg of N/ha/year is recommended to obtain greater biomass production and nutrients, nutritional quality, and nitrogen use efficiency.

Resumen El objetivo de la presente investigación fue evaluar el efecto de diferentes niveles de suplementación concentrada (0 %, 1,5 %, 3,0 %, en relación con el peso vivo) y dos especies forrajeras como Megathyrsus maximus cv. Aruana y Brachiaria brizantha cv. Marandú en el rendimiento del quinto cuarto en corderos Suffolk. En total, 36 corderos machos enteros fueron distribuidos en 12 piquetes de 32 m × 32 m. Los animales recibieron sal y agua ad libitum durante el experimento, así como su correspondiente ración concentrada ofrecida diariamente a las 8:00 a. m. Un puntaje de condición corporal de 2,5 a 3,0 fue utilizada como parámetro para la faena. El diseño fue completamente al azar en un arreglo factorial 3 × 2 (tres niveles de suplementación y dos tipos de pasturas). Se evaluó el peso corporal vacío (PCV), consumo de materia seca (CMS), ganancia de peso diario (GPD), componentes del quinto cuarto (CQC), tracto gastrointestinal y víscera roja, blanca y verde. El PCV, CMS, GPD y CQC fueron influenciados (p < 0,05) por los niveles de suplementación concentrada y tipos de pasturas, menores para animales sin suplementación en pastura Marandu. Asimismo, la cabeza, las patas, la sangre, el corazón, el hígado, el riñón, la víscera roja y la grasa omental e interna fueron inferiores (p < 0,05) en animales sin suplementación. Rumen retículo (lleno y vacío) y víscera blanca (lleno y vacío) fueron independientes del nivel de suplementación y tipos de pasturas. La no suplementación concentrada provoca menor desarrollo de los principales órganos vitales del cordero, más aún en pastura Marandú.

Abstract The objective of the present investigation was to verify the effect of different levels of concentrate supplementation (0 %, 1.5 %, 3.0 % in relation to live weight) and two forage species such as Megathyrsus maximus cv. Aruana and Brachiaria brizantha cv. Marandu in fifth quarter performance in Suffolk lambs. In total, 36 entire male lambs were distributed in 12 pickets of 32 m × 32 m. The animals received salt and water ad libitum during the experiment and the concentrated ration offered daily at 08:00 AM. Body condition score of 2.5 to 3.0 was used as parameters for slaughter. The design was completely randomized in a 3 × 2 factorial scheme (three levels of supplementation and two types of pasture). Empty body weight (EBW), dry matter intake (DMI), daily weight gain (DWG), fifth quarter components (FQC), gastrointestinal tract and red, white and green viscera were evaluated. EBW, DMI, DWG and FQC were influenced (P < 0.05) by the levels of concentrated supplementation and types of pastures, lower for animals without supplementation in Marandu pasture. Likewise, head, foot, blood, heart, liver, kidney, red viscera, omental and internal fat were lower (P < 0.05) in animals without supplementation. Rumen reticulum (full and empty) and white viscera (full and empty) independent of the level of supplementation and types of pasture. The non-concentrated supplementation causes less development of the main vital organs of the lamb, even more in Marandu pasture.

RESUMO: Esta pesquisa foi realizada com o objetivo de se avaliar a produtividade da biomassa e valor nutricional da silagem e do feno provenientes do consórcio entre o capim-Tamani e diferentes espécies de leguminosas. Para as características produtivas das diferentes culturas consorciadas, adotamos o delineamento de blocos ao acaso, para avaliação da interação dos consórcios com técnicas de conservação usamos esquema fatorial 5 x 2 (cinco consórcios e duas técnicas de conservação). Os tratamentos foram o capim-Tamani em monocultura, e o consórcio de capim-Tamni associado a crotalária, soja, feijão-caupi ou feijão-guandu. As plantas foram semeadas em fileiras alternadas, com espaçamento de 45 cm. As técnicas de conservação foram silagem pré-secada (520 g / kg de MS) e feno (870 g / kg de MS). Avaliamos a produção de biomassa de gramínea e leguminosa, a altura do dossel, a composição química e a digestibilidade in vitro da matéria seca (ivDMD). Não houve diferenças na produção total de biomassa entre os consórcios e o monocultivo de capim-Tamani. Os tratamentos consorciados com feijão-caupi e soja tiveram maior participação de leguminosas na mistura, promovendo aumento no teor de proteína bruta e ivDMD da silagem pré-secada e feno. A silagem pré-secada e o feno tinham a mesma composição química, embora a silagem pré-secada apresentou maior ivDMD do que o feno. Concluímos que o consórcio de capim-Tamani com soja ou feijão-caupi manteve a produtividade da biomassa total e melhorou o valor nutricional da silagem pré-secada e do feno.

ABSTRACT: This research evaluated the biomass productivity and nutritional value of the haylage and hay from intercropping between Tamani grass and different legume species. For the productive characteristics of the different intercrops, we adopted a randomized block design, for evaluation of the combination of intercropping and conservation technic we used 5 x 2 factorial scheme (five intercrops and two types of conservation techniques). The treatments were Tamani grass as monoculture, and the intercrops of Tamani grass with crotalaria, soybean, cowpea, or pigeon pea. The conservation techniques were haylage (520 g/kg of DM) and hay (870 g/kg of DM). Plants were sown in alternate rows, with 45 cm of spacing between the rows. The parameters evaluated were grass and legume biomass production, canopy height, and haylage and hay chemical composition, and in vitro dry matter digestibility (ivDMD). There were no differences in the total biomass production between the intercrops and TA grass monoculture. The treatments intercropped with cowpea and soybean had the highest legume participation in the mixture, promoting an increase in crude protein and ivDMD content of haylage and hay. Haylage and hay had the same chemical composition, although haylage had higher ivDMD than hay. We concluded that intercropping Tamani grass with soybeans or cowpea maintained total biomass productivity and improved the nutritional value of haylage and hay.

ABSTRACT The aim of the present meta-analytical study was to evaluate the effect of glycerol in the diet on the productive performance, nutrient digestibility and the characteristics of the carcass and meat of fattening goats. A systematic review was made using the Google Scholar, ScienceDirect and SciELO databases. Keywords such as crude glycerine, intake, goat, kids, carcass, meat quality were used. As inclusion criteria of the scientific articles, the presence of a control treatment (0% glycerol) and at least a percentage of glycerol in the diet, data regarding the digestibility of nutrients, productive response, characteristics of the carcass and meat and glycerol level in crude glycerin were considered in papers published between 2014 and 2019. In total, 56 articles were selected, of which 11 met the inclusion criteria. Given the heterogeneity or amplitude of the glycerol levels, the levels were grouped: 0, 1.27-4.38 and 6.40-9.60% of glycerol based on the dry matter of the diet. Normality, variance and regression analyses were performed from the data of each variable within each level of glycerol in the diet. The high variation of glycerol levels in crude glycerine was evidenced. Glycerol up to 9.60% in the diet does not compromise digestibility, consumption, main characteristics of the carcass and goat meat.

RESUMEN El objetivo del presente estudio meta-analítico fue evaluar el efecto del glicerol en la dieta sobre el comportamiento productivo, digestibilidad de nutrientes y las características de la canal y carne de cabras en engorde. Se hizo una revisión sistemática utilizando las bases de datos de Google Scholar, ScienceDirect y SciELO. Palabras clave como crude glycerin, intake, goat, kids, carcass, meat quality fueron utilizados. Como criterios de inclusión de los artículos científicos se consideraron la presencia de un tratamiento testigo (0% de glicerol) y por lo menos un porcentaje de glicerol en la dieta, datos referentes a la digestibilidad de los nutrientes, respuesta productiva, características de la canal y carne y nivel de glicerol en la glicerina bruta en trabajos publicados entre 2014 y 2019. Se seleccionaron 56 artículos, de los cuales 11 reunieron los criterios de inclusión. Ante la heterogeneidad o amplitud de los niveles de glicerol, los niveles fueron agrupados: 0, 1.27-4.38 y 6.40-9.60% de glicerol en base a la materia seca de la dieta. Análisis de normalidad, variancia y de regresión fueron realizadas a partir de los datos de cada variable dentro de cada nivel de glicerol en la dieta. Se evidenció la alta variación de los niveles de glicerol en glicerina bruta. Glicerol hasta 9.60% en la dieta no compromete la digestibilidad, consumo, principales características de la canal y carne de cabra.

ABSTRACT Objective. To evaluate the quantitative characteristics of the carcass and chemical composition of the meat of purebred Santa Inês (SI) lambs and crosses with Dorper (DO-SI) or Texel (TX-SI), finished in feedlot or semi-feedlot, through a meta-analysis. Materials and methods. Virtual databases such as Google Scholar, Science Direct and Scielo were used to select scientific articles published from 2000 to 2019. Keywords such as genotype, lambs, carcass characteristics and meat quality, both in Spanish, Portuguese and English were used as criteria for the inclusion of articles. From each genetic group were evaluated: animal performance, quantitative characteristics of the carcass, carcass cuts and chemical composition of the meat. These variables were included in the analysis from 37 scientific articles. Results. Final body weight, hot carcass weight, cold carcass yield and muscle percentage do not differ between the different genetic groups evaluated. DO-SI lambs showed higher dry matter intake, daily weight gain, loin eye area and loin percentage. Chemical composition was not influenced by the genetic groups. Conclusions. In a tropical and subtropical environment, purebred lambs SI finished in feedlot or semi-feedlot have quantitative characteristics of the carcass and chemical composition similar to DO-SI and TX-SI lambs.

RESUMEN Objetivo. Evaluar las características cuantitativas de la canal y composición química de la carne de corderos puros Santa Inés (SI) y cruces con Dorper (DO-SI) o Texel (TX-SI), terminados en confinamiento o semiconfinamiento, mediante un meta-análisis. Materiales y métodos. Bases de datos virtuales como Google Scholar, Science Direct y Scielo fueron utilizados para seleccionar los artículos científicos publicados desde el año 2000 a 2019. Palabras clave como genotipo, corderos, características de la canal y calidad de la carne, tanto en idioma español, portugués e inglés fueron utilizadas como criterios de inclusión de los artículos. De cada grupo genético, fueron evaluados: desempeño animal, características cuantitativas de la canal, cortes de la canal y composición química de la carne. Todos fueron incluidos en el análisis proveniente de 37 artículos científicos. Resultados. Peso corporal final, peso de la canal caliente, rendimiento de la canal fría y porcentaje de músculo no difieren entre los diferentes genotipos evaluados. Corderos DO-SI presentaron mayor consumo de materia seca, ganancia diaria de peso, área de ojo de lomo y porcentaje de lomo. Composición química no fue influenciada por los genotipos. Conclusiones. En ambiente tropical y subtropical, corderos puros SI terminados en confinamiento o semiconfinamiento presentan características cuantitativas de la canal y composición química similar a los corderos de cruces DO-SI y TX-SI.

Resumo: O objetivo deste trabalho foi avaliar o desempenho produtivo e as características da carcaça de cordeiros alimentados com silagens de diferentes tipos de sorgo e milho. Foram utilizados 32 cordeiros machos, da raça Suffolk. O delineamento experimental foi inteiramente casualizado, com quatro tratamentos (silagens) e oito repetições (animais). Foram testadas silagens de sorgo forrageiro GrandSilo, sorgo sacarino BRS 506, sorgo sacarino BRS 511 e milho híbrido duplo BRS 2223. Os cordeiros alimentados com silagens de sorgo apresentaram menor consumo diário de matéria seca que os alimentados com silagem de milho. A dieta contendo silagem de milho proporcionou ganho de peso 27% superior ao dos tratamentos com as demais silagens. A digestibilidade in vivo não diferiu entre as diferentes silagens. Os cordeiros alimentados com silagem de milho apresentaram os menores rendimentos de carcaça quente e fria, de 44,71 e 42,62%, respectivamente, enquanto os que consumiram silagem de sorgo BRS 506 apresentaram os maiores rendimentos de carcaça quente e fria, de 46,90 e 44,78%. O maior consumo e o melhor desempenho dos animais alimentados com silagem de milho não foi suficiente para incrementar a produção e o rendimento de carcaça. Os cordeiros alimentados com silagem de sorgo sacarino BRS 506 apresentam maior eficiência de conversão da silagem em carcaça.

Abstract: The objective of this work was to evaluate the productive performance and carcass traits of lambs fed silages of different types of sorghum and corn. Thirty-two uncastrated male Suffolk lambs were used. The experimental design was completely randomized, with four treatments (silages) and eight replicates (animals). Silages of the GrandSilo forage sorghum, BRS 506 saccharine sorghum, BRS 511 saccharine sorghum, and the BRS 2223 double-grain corn hybrid were tested. The lambs fed sorghum silages had a lower daily dry matter intake than those fed corn silage. The diet containing corn silage led to 27% greater weight gain, when compared with the treatments with the other silages. In vivo digestibility did not differ among the different silages. Lambs fed corn silage showed the lowest hot and cold carcass yields of 44.71 and 42.62%, respectively, whereas those that consumed BRS 506 sorghum silage showed the highest hot and cold carcass yields of 46.90 and 44.78%. The greater intake by and the better performance of the animals fed corn silage was not enough to enhance production and carcass yield. Lambs fed BRS 506 saccharine sorghum silage have higher efficiency in the conversion of silage into carcass.

Resumo: O objetivo deste trabalho foi avaliar quatro variedades de sorgo sacarino (Sorghum bicolor)quanto à produtividade, à composição química das partes da planta e à qualidade do processo de ensilagem. As variedades de sorgo sacarino utilizadas foram BRS 506, BRS 508, BRS 509 e BRS 511. O experimento foi dividido em dois ensaios, que avaliaram: produção, composição morfológica e qualidade nutricional das variedades sacarinas; e qualidade do processo fermentativo e valor nutricional das silagens das variedades sacarinas. Das variedades testadas, a BRS 509 e a BRS 511 foram as que apresentaram maiores produções de matéria seca (MS) total. A variedade BRS 508 apresentou o maior coeficiente de digestibilidade in vitro da planta inteira (70,65% da MS). Durante a ensilagem, a variedade BRS 509 foi a que apresentou menor perda de MS (8,87%). A maior produção de efluentes foi observada para BRS 506 e BRS 508, com produção de 521,87 e 393,16 kg Mg-1 de MS ensilada, respectivamente. A variedade BRS 511 é a mais indicada em razão dos melhores resultados de produção e de qualidade nutricional da planta. Em relação ao processo de ensilagem, a BRS 509 apresenta as menores perdas fermentativas e o maior valor nutritivo da silagem.

Abstract: The objective of this work was to evaluate four cultivars of saccharine sorghum (Sorghum bicolor) regarding productivity, chemical composition of plant parts, and quality of the ensiling process. The tested varieties of saccharine sorghum were BRS 506, BRS 508, BRS 509, and BRS 511. The experiment was divided into two trials, which assessed: production, morphological composition, and nutritional quality of the saccharine varieties; and fermentation quality and nutritional value of the silage produced from the saccharine varieties. Of the tested varieties, BRS 509 and BRS 511 showed the highest total dry matter (DM) production. The BRS 508 variety presented the highest in vitro digestibility of the whole plant (70.65% DM). During ensiling, the BRS 509 variety showed the lowest DM loss (8.87%). The highest effluent production was observed for BRS 506 and BRS 508, with yields of 521.87 and 393.16 kg Mg-1 ensiled DM, respectively. The BRS 511 variety is the most recommended because of the best results for plant production and nutritional quality. Regarding the ensiling process, BRS 509 presents the lowest fermentation losses and the highest nutritional value of silage.

The objectives of this study were to determine the chemical composition of vegetable and mixed crude glycerin and digestible energy to and evaluate different inclusion levels in rabbit feeding. A total of 108 rabbits were used in the digestibility assay, assigned in a completely randomized design into nine treatments, one reference diet plus eight test diets, where the glycerin types were included at levels of 4, 8, 12 and 16%, replacing the reference diet roughage. In the performance assay, 180 rabbits were assigned to a completely randomized design into a 2 × 4 factorial arrangement (two types of glycerin and four levels of inclusion: 3, 6, 9 and 12%) plus a reference diet and ten replications. The vegetable and mixed crude glycerin showed digestible energy of 5,099 and 4,953 kcal/kg of dry matter, respectively. Although feed intake decreased linearly with the growing inclusion of both kinds of glycerin during both evaluated periods (from 32 to 50 and 32 to 70 days), performance losses occurred only with the inclusion of vegetable crude glycerin. The inclusion of mixed crude glycerin up to 12% allowed similar animal performance to the reference diet up to 50 days, unlike vegetable crude glycerin, for which inclusions over 6% in the diet resulted in poorer performance compared with that obtained with the reference diet. In the total period, differences were not observed for live weight or weight gain of the animals fed both glycerin types. Carcass weight decreased linearly with the inclusion of both glycerin types, with lower values compared with the reference diet only for the two highest levels of glycerin inclusion. Mixed crude glycerin can be included up to the maximum level studied (12%), while vegetable glycerin can be added up to 6% in the diet of growing rabbits.

A total of 70 five-month-old female New Zealand White rabbits were assigned in a completely randomized design, over three reproductive cycles, with two treatments: a reference diet and a half-simplified diet containing 79.83% cassava byproduct. The study evaluated body weight and feed intake of does, feed cost, number and total body weight of kits at kindling and weaning per female during three cycles, number and percentage of mortality/female/cycle, and weight gain of kits from birth to weaning. No interaction was observed between the diets and among the reproductive cycles for any evaluated characteristics. The body weight of does at the moment of weaning was similar in both groups for all three reproductive cycles. However, does fed the half-simplified diet had lower feed intake during the three reproductive cycles and, consequently, more reproductive flaws. The number of kits at weaning, body weight of kits at kindling and weaning, weight gain of kits from birth to weaning, and total body weight of kits at weaning were lower for the group of does fed the half-simplified diet and, consequently, there was a higher number and percentage of dead kits in this group. The total numbers of kits at kindling and weaning and total body weight of kits at birth during all three reproductive cycles were similar between the groups; however, total body weight of weaning rabbits was higher for the animals receiving the reference diet. It is possible to conclude that although the use of the half-simplified diet decreases the reproductive performance of does, it reduces feed cost per kg of body weight by 23.63% compared with the reference diet, proving to be a viable nutritional option for rabbit production.

Dois experimentos foram realizados para determinar o valor nutritivo da silagem de grãos úmidos de milho (SGUM) e avaliar os efeitos da substituição gradativa do milho seco das rações pela SGUM sobre o desempenho e características quantitativas de carcaça de coelhos, no período de 36 a 70 dias de idade. No ensaio de digestibilidade, foram utilizados 22 coelhos da raça Nova Zelândia Branco, com 50 dias de idade, alojados individualmente em gaiolas de metabolismo, em delineamento inteiramente ao acaso, com dois tratamentos e 11 repetições. Os valores da matéria seca digestível, proteína bruta digestível, energia bruta digestível, fibra em detergente neutro digestível, fibra em detergente ácido digestível e amido digestível da SGUM foram, respectivamente, 94,42%; 7,94%; 3973kcal kg-1, 6,74%; 2,61% e 68,73%. No experimento de desempenho, foram utilizados 110 coelhos, distribuídos em um delineamento inteiramente casualizado, com cinco tratamentos, 11 repetições e dois animais por unidade experimental. Os tratamentos consistiram de uma dieta referência e outras quatro com 25, 50, 75 e 100% de substituição do milho pela SGUM, com base na matéria seca do milho incluído na dieta referência. Não foram observadas diferenças entre os tratamentos no desempenho, tanto no período de 36 a 50 dias como no período total do experimento, de 36 a 70 dias de idade. Nenhuma diferença foi observada no peso e rendimento de carcaça entre os tratamentos. Diante dos resultados, a SGUM substitui eficientemente o milho seco em dietas para coelhos.

Digestibility and performance experiments were carried out to evaluate the nutrients digestibility coefficients of high moisture corn silage (HMCS) and the gradative replacing (0, 25, 50, 75 and 100%) of dry grain corn by HMCS on performance and carcass yield of growing rabbits from 36 to 70 days old. In the digestibility experiment 22 rabbits were used allocated on a completely randomized design, with two treatments and 11 replicates. The values of digestible dry matter, digestible crude protein, digestible crude energy, digestible neutral fiber detergent, digestible acid fiber detergent and digestible starch were, respectively, 94.42%; 7.94%; 3973kcal kg-1; 6.74%; 2.61% and 68.73%. In the performance experiment, 110 rabbits were allocated on a completely randomized design, with five treatments, 11 replications and two rabbits per experimental unit. The HMCS replaced the dry grain corn in levels of 0, 25, 50, 75 and 100%, on dry matter basis. No differences were observed on performance in the period from 36 to 50 and the period from 36 to 70 days old. No difference was observed also on weight and carcass yield. The results showed that the HMCS replaces efficiently the dry grain corn in rabbit diets.

Este trabalho teve por objetivo estudar a influência da fibra oriunda de diferentes fontes (feno de alfafa, farelo de linhaça e farelo proteinoso de milho) sobre o desempenho, coeficientes de digestibilidade e características da carne de coelhos em crescimento. Os animais foram distribuídos em um delineamento inteiramente casualizado com três tratamentos e oito repetições, sendo uma ração referência e duas rações testes: FA - ração controle, com feno de alfafa; FL - substituição total do feno de alfafa por farelo de linhaça e FP - substituição total do feno de alfafa por farelo proteinoso de milho. Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste Duncan (P<0,05). A maior quantidade de hemicelulose e a baixa capacidade de hidratação das dietas FA e FP proporcionaram maior peso vivo dos animais aos 89 dias (2123 e 1934 g, respectivamente) contra 1797 g da dieta FL e melhor coeficiente de digestibilidade da MS e MO (média de 80,80 para MS e 81,76% para MO, respectivamente) em relação à dieta FL (73,86 e 75,84%, respectivamente). A dieta FP apresentou maior coeficiente de digestibilidade para a FDN (56,59%) contra a média de 33,11% para as demais dietas. A força de cisalhamento foi menor para a carne dos animais alimentados com FA e FP (1,90 e 1,63 kgf) em comparação com a FL (2,33 kgf) (P<0,05), o que indica carne mais macia. O farelo proteinoso de milho proporcionou peso vivo dos animais aos 89 dias semelhante ao do feno de alfafa. O farelo de linhaça, pela grande quantidade de fibra solúvel e alta capacidade higroscópica, prejudicou o desempenho dos animais e a maciez da carne.

The objective of this paper was to study the influence of fiber fractions from different sources (alfalfa hay, linseed bran and corn gluten meal) on performance, digestibility coefficients and meat characteristics of growing rabbits. The animals were distributed into a completely randomized design with three treatments and eight replications, with one reference and two test diets: AH- control diet, with alfalfa hay; LB- total substitution of alfalfa hay by linseed bran and GM- total substitution of alfalfa hay by corn gluten meal. The data were submitted to variance analysis and the averages were compared by Duncan test (P<.05). The largest amount of hemicellulose and the low hydration capacity of the diets AF and GM proportioned greater animals live weight at 89 days of age (2123 and 1934 g, respectively) versus 1797 g of the animals fed with the diet LB and better digestibility coeficients of DM and OM (average of 80.80 for DM and 81.76% for OM, respectively) in relation to diet LB (73.86 and 75.84%, respectively). The diet GM showed a higher digestibility coefficient of NDF (56.59%) against the average of 33.11% for the other diets. The shear force was lower for meat from animals fed with AH and GM (1.90 and 1.63 kgf) compared to LB (2.33 kgf) (P<.05), which indicates meat tenderness. The corn gluten meal proportioned live weight to the animals at 89 days of age similar to the alfalfa hay. The linseed bran, due to large amount of soluble fiber and high hydration capacity, impaired animal performance and meat tenderness.