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.

This study evaluated the ingestive behaviour and performance of feedlot lambs fed saccharine sorghum and corn silages. Ten animals were randomly selected from a group of 32 uncastrated male Suffolk lambs. The four treatments consisted of diets with 50% of silage made from forage sorghum (BD 1615), two varieties of saccharine sorghum (BRS 506 and BRS 511), and corn (BRS 2223). Ingestive behaviour was observed by a scan sampling method using seven strategically positioned video cameras so as not to interfere with the usual animal behaviour. The animals were observed for three 48-hour periods at 15-day intervals, with a total of 144 hours of observation. Video recordings were then examined to identify the time spent in ruminating, eating, drinking water and idling. Times spent feeding or drinking water were not significantly affected by the treatments. Animals fed forage sorghum silage had higher neutral detergent fibre (NDF) intake (0.41 kg of NDF), thus spent more time ruminating (342 min/day). Rumination time was similar for the BD 1615 and BRS 506 silages and was 85 min/day greater than for the BRS 511 and BRS 2223 silages, which were similar. Average daily gain was greater for BRS 2223 (275 g/day) than for BRS 506 and BRS 511 silages, which were similar (196 g/day). Ingestive behaviour for BRS 511 was similar to that observed for BRS 2223. Ingestive behaviour for BRS 506 was similar to that observed for BD 1615. Average daily gain was related to intake and ruminating efficiency.

Objectives of this study were to evaluate effects of grazing tropical forage species and level of supplementation with grain on characteristics of lamb meat. Ninety-day-old lambs (n = 36) (22.54 ± 2.72 kg) were randomly assigned to a 2 x 3 factorial arrangement of pasture types (Aruana and Marandu) and levels of concentrate supplementation (0%, 1.5% and 3% of bodyweight). Water retention capacity, shear force, weight loss after cooking, pH, colour, and intramuscular lipid content of the meat were evaluated. A panel of 145 consumers evaluated the appearance, flavour, fat flavour, odour, and softness of the meat and provided an overall assessment. Supplementation at 3% of bodyweight reduced the luminosity of the meat. The appearance of meat from lambs that grazed Aruana grass was deemed preferable to that of meat from lambs that grazed Marandu grass. Total branched-chain fatty acids (BCFAs) were increased when grazing Marandu grass compared to Aruana grass. Lambs supplemented with concentrate had reduced BCFA/kg of meat and its content of both monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids were increased. Supplementation with concentrate at 1.5% and 3.0% of bodyweight increased n-6 PUFAs by 16.8% and 90.0%, decreased n-3 PUFAs by 49.7% and 35.9%, and thus increased the n-6/n-3 ratio by 135.0% and 183.8%, respectively. Lambs that were finished on grass without supplementation had a more healthful fatty acid profile and received better scores for flavour and global appreciation. To improve the quality of fatty acids in the meat, the pasture system is recommended.

Avaliaram-se as características quantitativas e qualitativas do sêmen de coelhos alimentados com uma ração referência e outra ração formulada com 79,83% de subprodutos de mandioca. Utilizaram-se 20 reprodutores da raça Nova Zelândia Branco, com idade média inicial de sete meses, alojados individualmente em gaiolas e distribuídos em delineamento experimental inteiramente ao acaso, com duas dietas e dez repetições. Realizaram-se dez colheitas de sêmen por animal durante seis meses. Avaliaram-se o volume de sêmen sem gel e volume de gel, cor do sêmen, pH, motilidade espermática progressiva, vigor espermático, concentração espermática, número de espermatozoides no ejaculado, espermatozoides normais, anormais e anormalidades primárias e secundárias. O volume de sêmen sem gel, o índice de normalidade, as anormalidades primárias e secundárias foram iguais (P>0,05) para os animais alimentados com a ração referência e a com subprodutos de mandioca. Os demais parâmetros do sêmen foram melhores (P<0,05) nos animais tratados com a ração com subprodutos de mandioca. Os resultados das características quali-quantitativas do sêmen dos coelhos da Raça Nova Zelândia Branco demonstram que é possível utilizar ração com 79,83% do volume da formulação com subprodutos de mandioca, na dieta de reprodutores, sem prejuízos nas características do sêmen, desde que observados os níveis reduzidos de taninos e ácido cianídrico.

The quantitative and qualitative rabbit semen characteristics fed with a reference diet and a diet formulated with 79.83% of cassava by-products were evaluated. 20 New Zealand White rabbit bucks, with initial average age of seven months were used, individually allocated and distributed in a completely ramdomized design, with two diets (treatments) and ten replications. The ten semen collections per animal were taken during six months. The evaluated parameters were: semen volume without gel and gel volume, color of semen, pH, spermatic progressive motility, spermatic vigor, spermatic concentration, spermatozoa number in the ejaculation, normal spermatozoa, abnormal and primary and secondary abnormalities spermatozoa. The semen volume without gel, the normal spermatozoa, primary and secondary abnormalities spermatozoa were similar (P>0.05) to the animals fed with cassava by-products diet and reference diet. Other semen parameters were better (P<0.05) in the animals fed with the cassava by-products diet. The results of the quali-quantitative characteristics of the semen from New Zealand White rabbits showed that it is possible to use diets containing 79.83% of inclusion of cassava by-products in the diet of rabbit bucks, without affecting semen characteristics, since we observed the reduced level of tannins and hydrocyanic acid.

Dois experimentos foram conduzidos com o objetivo de determinar a energia digestível da glicerina semipurificada vegetal e mista e o desempenho de coelhos em crescimento alimentados com dietas contendo os coprodutos. No ensaio de digestibilidade, foram utilizados 108 coelhos da raça Nova Zelândia Branco, com 45 dias de idade, distribuídos ao acaso em nove tratamentos (0, 4, 8, 12 e 16% de inclusão de glicerina vegetal e mista na dieta), com 12 repetições. Para o ensaio de desempenho, utilizaram-se 180 coelhos da raça Nova Zelândia Branco, dos 32 aos 70 dias de idade, distribuídos ao acaso em arranjo fatorial 2 x 4 (dois tipos de glicerina e quatro porcentagens de inclusão: 3, 6, 9 e 12%) mais uma dieta referência, com 10 repetições e dois animais por unidade experimental. Glicerinas vegetal e mista apresentaram energia digestível de 4.048 e 3.697kcal/kg MS, respectivamente. Entre 32 e 50 dias de idade dos coelhos, a dieta com 12% de glicerina mista prejudicou (P<0,05) o ganho de peso (32,14 g/dia), a conversão alimentar (3,57) e o custo por quilo de ganho de peso (R$ 2,08) em relação à dieta referência (39,42g/dia, 2,87 e R$1,69, respectivamente). Dos 32 aos 70 dias, o ganho de peso (30,11g/dia) e a conversão alimentar (3,99) dos animais que receberam 12% de glicerina mista na dieta foram piores (P<0,05) em relação aos da dieta referência (34,00g/dia e 3,65, respectivamente). Para as características de desempenho, dos 32 aos 70 dias, não foram verificadas diferenças (P>0,05) entre a inclusão de glicerina vegetal na dieta e a dieta referência, porém a maior viabilidade econômica (P<0,05) foi com 12% de inclusão (R$1,89 x R$2,15, respectivamente). A glicerina vegetal pode ser incluída em até 12% da dieta e a mista, em até 9%, diminuindo o custo de produção sem afetar o desempenho animal.

Two trials were conducted with the goal of determining the digestible energy of vegetal and mixed semi purified glycerin and the performance of growing rabbits fed with diets containing the byproducts. In the digestibility assay 108 New Zealand White rabbits, 45 days old, were used, assigned in a completely randomized design into nine treatments (0, 4, 8, 12 and 16% of glycerins inclusion), with 12 replications. The treatment with 0% of glycerin inclusion was considered the reference diet. In the performance assay, 180 New Zealand White rabbits, 32 to 70 days of age, were assigned to a completely randomized design into a 2 × 4 factorial arrangement (two types of glycerin and four percentages of inclusion: 3, 6, 9 and 12%) plus a reference diet and ten replications with two animals per experimental unit. Vegetal and mixed glycerin showed a digestible energy of 4,048 and 3,697 kcal/kg of dry matter, respectively. From 32 to 50 days of age, the diet with 12% of mixed glycerin affected (P<0.05) weight gain (32.14g/day), feed conversion (3.57) and cost per kilo of weight gain (R$2.08) in relation to the reference diet (39.42g/day, 2.87 and R$ 1.69, respectively). From 32 to 70 days, weight gain (30.11g/day) and feed conversion (3.99) of the animals fed with the diet containing 12% of mixed glycerin were worst (P<0.05) in relation to the reference diet (34.00 g/day and 3.65, respectively). Regarding characteristics of animal performance, from 32 to 70 days, no differences (P>0.05) were observed between the inclusion of vegetal glycerin in the diet and the reference diet, but better economic viability was verified (P<0.05) with the diet containing 12% of vegetal glycerin (R$1.89 x R$2.15, respectively). Vegetal glycerin can be included up to 12% in the diet and mixed up to 9%, reducing production cost without affecting animal performance.

Estudou-se a influência da fibra oriunda de diferentes fontes - feno de alfafa, polpa de cítrus e casca de soja - sobre o desempenho, coeficientes de digestibilidade, parâmetros sanguíneos e características da carne de coelhos submetidos às dietas experimentais. Os animais foram distribuídos em três tratamentos, que consistiram de: FA - ração-controle, com feno de alfafa; PC - substituição total do feno de alfafa por polpa de cítrus; e CS - substituição total do feno de alfafa por casca de soja. As diferentes frações da fibra advindas da polpa de cítrus e da casca de soja não influenciaram o desempenho dos animais aos 89 dias e mostram que esses ingredientes podem ser utilizados como substitutos do feno de alfafa na dieta de coelhos. A qualidade de fibra da polpa de cítrus reduziu os níveis séricos de triacilglicerol, colesterol e hemoglobina dos animais. A baixa quantidade de lignina em relação à celulose e à hemicelulose da casca de soja propiciou melhor coeficiente de digestibilidade dos nutrientes e maior maciez da carne, porém menor deposição proteica quando comparada com a dieta com polpa de cítrus.

The influence of fiber - alfalfa hay, citrus pulp, and soybean hulls - in diets of rabbits was studied on performance, digestibility coefficients, blood parameters, and meat characteristics. The animals were allotted into three treatments that consisted in: control diet, with alfalfa hay; total substitution of alfalfa hay by citrus pulp; and total substitution of alfalfa hay by soybean hulls. The different fiber fractions from citrus pulp and soybean hulls did not affect animal performance at the 89th day; thus, these ingredients can be used as substitute of alfalfa hay on diet of rabbits. Fiber quality of citrus pulp decreased blood triacylglycerol, cholesterol, and hemoglobin levels. Lower amount of lignin in relation to cellulose and hemicellulose of soybean hulls provided better nutrient digestibility coefficients and higher tenderness meat, however, lower protein deposition when compared with the citrus pulp diet.

Avaliaram-se a composição física da carcaça e a qualidade da carne de 22 novilhos contemporâneos, com média de idade de 22 meses, das raças Charolês ou Nelore, terminados em confinamento, e que receberam diferentes proporções de concentrado na dieta. A fração volumosa da dieta foi composta pelas silagens de milho e sorgo em partes iguais. Os animais foram distribuídos em três tratamentos constituídos por 35, 50 ou 65% de concentrado na matéria seca. Não houve efeito (P>0,05) da porcentagem de concentrado na dieta sobre a composição física da carcaça. A proporção de inclusão do concentrado influenciou (P=0,0013) positivamente a maciez da carne, aumentando em 0,026 pontos a cada ponto percentual de aumento do concentrado. As demais características qualitativas da carne não foram influenciadas (P>0,05) pelo aumento do concentrado na dieta. A carne dos novilhos Charolês apresentou textura mais fina, 4,15 x 3,14 pontos, foi mais macia, 6,85 x 5,71 pontos, mais suculenta, 7,17 x 5,77 pontos, e apresentou menor resistência das fibras ao cisalhamento, 3,79 x 5,79kgF. A carcaça dos novilhos Charolês apresentou maior deposição muscular, 65,5 x 61,5%, e a dos novilhos Nelore apresentou maior percentagem de gordura, 23,3 x 20,3%.

The physical compositionof carcass and meat quality of 22 Charolais (C) and Nellore (N) steers, feedlot finished and fed different levels of concentrate in the diet, were evaluated. The roughage fraction of the diet was made up by equal parts of corn and sorghum silages. The animals were distributed in three treatments constituted by 35, 50, or 65% of concentrate, in dry matter basis. Concentrate level did not affect carcass physical composition (P>0.05). Meat tenderness was positively affected (P=0.0013) by the concentrate level, increasing 0.026 points for each percent point increase of concentrate. The other meat qualitative characteristics were not affected by the concentrate level in the diet (P>0.05). Charolais steers showed meat with lighter color (4.44 x 2.89; P=0.0013), finer texture (4.15 x 3.14 points), better tenderness (6.85 x 5.71 points; P=0.0010), higher juiciness (7.17 x 5.77 points), lower Shear force (3.79 x 5.79kgf), and carcasses with higher muscle deposition (65.5 x 61.5%) in relation to N steers. Carcasses of Nellore steers showed higher fat percentage (23.3 x.20.3%).