ABSTRACT: The objective was to evaluate the animal production and ingestive behavior of the steers fed different supplements during the growth phase in Aruana grass, and the influence of this supplementation on production performance in feedlot phase. The treatments consisted of three supplements during the growing phase: mineral salt (0.12 g/kg of body weight - BW), low intake energy-protein supplement (1.26 g/kg of BW), and medium intake (3.76 g/kg of BW). Forage canopy characteristics, animal production, and animal behavior on pasture were evaluated in a completely randomized design with three replicates (paddocks). The titanium dioxide marker was used to determine the intake and apparent digestibility during the pasture phase. The production performance in feedlot was evaluated in a completely randomized design with eight replicates (animals). Twenty-four Aberdeen Angus steers (15 ± 1.5 months old; 364.8 ± 21.7 kg BW) were used. At the end of the growth phase the animals were confined and fed a single diet. Dry matter, crude protein, and neutral detergent fiber (NDF) contents of forage and intake were not influenced by the treatments. The average daily gain was higher for the medium intake supplement in pasture phase. The apparent digestibility of NDF (P = and chewing rate were higher for the medium intake supplement. The average daily gain and fat thickness of carcasses were higher for the medium intake supplement in the feedlot phase. The supplements of medium intake increase animal productivity during the growing phase on pastures and cattle’s finishing performance in intensive production systems.

RESUMO: O objetivo deste trabalho foi avaliar a produção animal e o comportamento ingestivo de novilhos alimentados com diferentes suplementos durante a fase de crescimento em capim Aruana, e a influência desta suplementação sobre o desempenho produtivo durante a fase de terminação em confinamento. Os tratamentos consistiram de três suplementos durante a fase de crescimento: sal mineral (0,12 g/kg do peso corporal - PC), suplemento energético-proteico de baixo consumo (1,26 g/kg do PC) e suplemento energético-proteico de médio consumo (3,76 g/kg do PC). As características do dossel forrageiro, a produção animal e o comportamento ingestivo em pastos de capim Aruana foram avaliados utilizando um delineamento inteiramente ao acaso com três repetições (piquetes). O marcador externo dióxido de titânio foi utilizado para determinar o consumo e digestibilidade aparente dos nutrientes na fase de pastagem. O desempenho em confinamento foi avaliado utilizando-se um delineamento inteiramente ao acaso com oito repetições (animais). Vinte e quatro novilhos Aberdeen Angus (15 ± 1,5 meses de idade; 364,8 ± 21,7 kg de peso corporal médio inicial) foram utilizados. Ao final da fase de recria, os animais experimentais foram confinados e alimentados com uma dieta única. Os teores de matéria seca, proteína bruta e fibra de detergente neutro (FDN) da forragem, bem como o consumo destas frações não foram alterados pelos tratamentos. O ganho médio diário foi superior para o suplemento de ingestão média na fase de pastagem. A digestibilidade da FDN e a taxa de ruminação na fase pastagem foram mais elevadas para o suplemento de média ingestão. O ganho médio diário e a espessura de gordura das carcaças foram mais elevados para o suplemento de ingestão média na fase de acabamento em confinamento. Suplementos de ingestão média aumentam a produtividade animal durante a fase de crescimento em pastagens e o desempenho em confinamento de bovinos provenientes de sistemas intensivos de produção.

ABSTRACT The objective of our study was to evaluate the effect of the use of legume (Arachis pintoi) or nitrogen fertilization on animal performance, characteristics of carcass and meat, and fatty acids profile of crossbred steers on Megathyrsus maximus cv. Aruana pasture, overseeded with temperate grasses. The experimental design was completely randomized, with three treatments and three replicates. The experiment was carried out from June to October (127 d). The treatments were: Low-N: 100 kg of N/ha; Medium-N: 200 kg of N/ha; and Legume: Arachis pintoi + 100 kg of N/ha. The pasture with higher nitrogen fertilization (N200) showed a more significant forage mass yield. The mixed grass with legumes presented a higher concentration of saturated fatty acids and saturated:unsaturated ratio in the meat. However, the grass pastures resulted in a higher content of unsaturated fatty acids in the meat. The other pasture variables, and characteristics of carcass and meat were not influenced by the treatments. The increase in nitrogen fertilization, from 100 to 200 kg/ha, and Arachis pintoi mixed with Aruana grass pasture overseeded with black oat and ryegrass does not affect the daily weight gain and the carcass and meat characteristics of the steers. The grass-legume mixture decreases the total concentration of unsaturated fatty acids in meat without influencing the concentration of polyunsaturated fatty acids.

ABSTRACT The purpose of this study was to evaluate the performance of beef cattle with two levels of energy-protein supplementation of low-consumption on African Bermudagrass pasture, overseeded in winter with oat and ryegrass, with or without irrigation. Twenty-four castrated Angus steers (11 months old and had an initial average of 220 kg body weight (BW)) were used in experimental area of 3.6 ha. The experiment was completely randomized in a 2×2 factorial design, with three replicates. The evaluation period was 249 days (July/2019 to March/2020). The treatments were: irrigated pasture with supplementation of 1 g/kg BW or 2.7 g/kg BW and non-irrigated pasture with 1 g/kg BW of supplement or 2.7 g/kg BW. The grazing method was continuous with a variable stocking rate. Irrigation provided pastures with better chemical composition in winter and spring. Irrigation increased the daily accumulation rate in winter (84.6 vs. 45.9 kg DM/ha/day), providing a greater stocking rate (1,702 vs. 1,385 kg/ha) and, consequently, body weight gain per hectare. Supplementation of 2.7 g/kg BW provided a greater stocking rate in winter (1,652 vs. 1,435 kg/ha) and spring (3,096 vs. 2,811 kg/ha), not changing in summer. The association of irrigation and supplementation of 2.7 vs. 1.0 g/kg BW improves the intake pattern by the animal in summer without changing productivity parameters. Irrigation increases productivity and the nutritional value of pasture with higher livestock production per area in periods of water deficit. The supply of 2.7 vs. 1.0 g/kg BW provides a greater stocking rate and body weight gain per hectare.

ABSTRACT The objective of this study was to evaluate the growth performance and meat quality of feedlot Aberdeen Angus steers fed high-concentrate diets with or without a natural feed additive composed of a mixture of yeasts and essential oils (EO). A completely randomized design with two diets (with or without natural feed additive) and 12 replicates was used. Twenty-four steers with initial shrunk body weight of 402.62±48.2 kg and average age of 18±2.0 months were used. Steers were fed ad libitum a diet containing 777.3 g of concentrate/kg dry matter (DM) and 222.7 g of corn silage/kg DM for 74 days. The mixture of yeast and EO was supplied at the rate of 10.0 and 0.117 g/animal/day, respectively. Average daily weight gain and feed efficiency in the adaptation period was greater in animals fed natural feed additive; however, there was no difference for the total experimental period. Dry matter intake, carcass weight, carcass yield, proportion of carcass bone, carcass muscle + fat:bone ratio, round thickness, and arm length were not altered by treatments. The inclusion of a natural feed additive in the diet increased the cooling loss (0.98 vs. 1.25%), proportion of carcass muscle (51.32 vs. 54.56%), carcass muscle:fat ratio (1.70 vs. 2.11%), leg length (68.79 vs. 70.71 cm), and arm perimeter (36.70 vs. 37.88 cm) and reduced the proportion of carcass fat (30.17 vs. 25.92%). Carcass length was greater in animals fed the diet with a natural feed additive. Meat color, texture, and marbling were not altered by treatments. The addition of natural feed additive to high concentrate diets does not alter the productive performance of feedlot Aberdeen Angus steers, although it can increase the proportion of lean meat of carcasses.

ABSTRACT The objective of this study was to investigate the effects of slaughter body weight (SW) on the performance, carcass characteristics, and meat quality of Jersey bulls in feedlots from weaning to slaughter. Eighteen Jersey bulls (125.7±15.9 kg; 5±0.6 months old) were used in the study. The treatments corresponded to three slaughter-weights: L360 – light weight, SW of 360 kg, M390 – medium weight, SW of 390 kg, and H420 – heavy weight, SW of 420 kg (n = 6/treatment); the animals were slaughtered at 368, 392, and 422 kg, respectively. The average daily gain was not influenced by SW. The M390 and H420 groups remained in feedlot, on average, 6 and 51 d longer, respectively, to reach a similar SW in relation to the L360 group. The increase in SW did not influence dry matter intake. However, the L360 group exhibited greater dry matter intake relative to body weight compared with the other two groups (29 vs. 26 g/kg). The increase in SW resulted in heavier and longer carcasses, with higher hot carcass yields. However, animals with greater SW had lower fat thickness. In addition, the increase in SW led to greater pistol cut, bone, and muscle weight for the carcasses. Although the meat color of Jersey bulls was darker in the H420 group, the meat was considered softer and more palatable by the consumer panel compared with the meat from the L360 group. The L360 group exhibited less fluid loss during thawing and cooking. Shear force measured by Warner Blatzer Shear was lower for H420. Animals slaughtered in the L390 group had an intermediate carcass weight, similar carcass yield, better cover fat and meat quality (color and shear) than animals slaughtered in the H420. Combining these factors with a shorter feedlot time compared with that of heavier animals, the SW of feedlot Jersey bulls is recommended at 390 kg.

RESUMO: Os efeitos da suplementação energética e da ervilhaca (Vica sativa L.) foram estudados para avaliar o perfil de ácidos graxos intramusculares de novilhos terminados em pastagens de aveia (Avena sativa L.). Foram avaliados 18 novilhos mestiços com 21 meses de idade. O experimento foi realizado em três tratamentos e seis repetições: pastagem de aveia (OA), pastagem de aveia + ervilhaca (OA + VET) e pastagem de aveia + suplementação (OA + SUP). A suplementação compreendeu a adição de fubá na dose diária de 1% do peso corporal dos animais. Os novilhos que receberam suplementação apresentaram maior teor lipídico no Longissimus lombar do que aqueles alimentados com OA + VET (1,25 contra 1,02%), enquanto aqueles alimentados com AO (1,15%) apresentaram valores intermediários. Os níveis de ácido linoléico conjugado foram maiores em novilhos alimentados com AO (0,57%) e OA + SUP (0,59%), enquanto a maior quantidade de ácidos graxos ômega-3 foi observada em animais alimentados com OA + VET (3,32%). Animais terminados em pastagens sem suplementação apresentaram menor proporção de n-6: n-3 (3,14). Novilhos terminados em pastagem de aveia com ervilhaca apresentaram gordura intramuscular mais saudável do que aqueles terminados com suplementação de milho moído, uma vez que apresentaram maior quantidade de PUFAs e melhor a relação n-6: n-3.

ABSTRACT: The effects of energetic supplementation and mixture vetch (Vica sativa L.) were studied to evaluate the intramuscular fatty acid profile of steers finished on oat (Avena sativa L.) pastures. Eighteen 21-month-old crossbred steers were evaluated. The experiment was carried out in three treatments and six repetitions: oat pasture (OA), oat pasture + vetch (OA + VET), and oat pasture + supplementation (OA + SUP). Supplementation comprised the addition of corn meal at a daily dose of 1% of the animals’ body weight. Steers receiving supplementation had higher lipid content in Longissimus lumborum than did those fed with OA + VET (1.25 vs 1.02%), whereas those fed with OA (1.15%) showed intermediate values. Conjugated linoleic acid levels were higher in steers fed OA (0.57%) and OA + SUP (0.59%), whereas the highest amount of omega-3 fatty acids was observed in animals fed OA + VET (3.32%). Pasture-finishing without supplementation resulted in a lower ratio of n-6:n-3 (3.14). Steers finished in oat mixture with vetch showed healthier intramuscular fat than did those finished with cornmeal supplementation; importantly, the higher the amount of PUFAs, the better n-6:n-3 ratio.

ABSTRACT This study was performed to determine and quantify the inherent auction factors that affect the selling price of beef calves (weanlings - from six to nine months old). Data on the selling price, location and month of the auction, genetic group, lot size live weight, and sex of animals were collected in 148 auctions from January 2004 to December 2014. A total of 4,312 lots corresponding to 48,588 calves were classified into seven genetic groups according to their phenotypic characteristics. The values were deflated using the General Price index (IGP-DI) inflation index and met the parametric assumptions. The selling price was standardized by the yearly median, assuming that its value corresponds to 100%, and the other values varied in their function. Path analysis quantified the direct and indirect effects of the variables taken as explanatory of the selling price, followed by regression analysis and Tukey test. Overall, the direct effect of the average weight was the highest (0.7), followed by sex (0.38). The smallest direct effect was the genetic group (−0.075). There was a growing exponential relationship between average weight of the lot and selling price and a decreasing ratio between price per kilo and the average weight of the lot (−0.0003 percentage points per kilogram). Males were generally 15.7% more valued than females. The British × Zebuine crossbreed was the most valued breed, followed by the British breed (8.9 and 3.6%, respectively). The highest premium was in November, followed by February (9.57 and 8.84%, respectively, compared with median year). The selling price increases linearly by 0.3284 percentage points for each additional animal in the lot. The average weight of the lot was found to be the most important variable in the formation of the selling price, followed by the sex of the animals.

Resumo Avaliaram-se os aspectos fermentativos e bromatológicos da silagem de cana-de-açúcar com adição de inoculante à base de Lactobacillus buchneri, associado ou não à adição de farelo de trigo (20%), de casca de soja (20%) ou à mistura de farelo de trigo (10%) + casca de soja (20%), utilizando delineamento inteiramente casualizado, com quatro repetições. Não foram observados efeitos significativos dos tratamentos sobre o pH da silagem, porém, observou-se temperatura mais elevada no tratamento contendo 10% de farelo de trigo + 10% de farelo de soja em relação aos tratamentos controle, CA e CCS20. A adição de fontes de carboidratos proporcionou aumento médio de 145,86 kg de MV/m3 nos valores de massa específica e, juntamente com a adição de inoculante biológico, recuperação de matéria seca em média 20,5% superior ao da silagem controle, além de elevar os teores de matéria seca em média 2,63% e de proteína bruta em 1,92%. Conclui-se que, isoladamente, a adição do inoculante biológico foi capaz apenas de reduzir as perdas do processo fermentativo em relação à silagem controle e que a adição de fontes de carboidratos, tanto casca de soja como farelo de trigo, melhora o valor nutritivo da silagem de cana-de-açúcar.

Abstract It was evaluated the fermentative and bromatological aspects of sugarcane silage with addition of Lactobacillus buchneri inoculant with or without the addition of wheat bran (20%), soybean hull (20%) or the mixture of wheat bran (10%) + soybean hull (20%), using a completely randomized design with four replicates. No significant effects of the treatments on the pH of the silage were observed, however, a higher temperature was observed in the treatment containing 10% of wheat bran + 10% of soybean meal in relation to the control treatment. The addition of carbohydrate sources provided an average increase of 145,86 kg of MV/m3 in the specific mass values and, together with the addition of biological inoculant, dry matter recovery averaged 20,5% higher than the control silage, in addition to increasing the dry matter contents in an average of 2,63% and crude protein in 1,92%. It is concluded that, in isolation, the addition of the biological inoculant was only able to reduce losses of the fermentative process in relation to the control silage and that the addition of carbohydrate sources, both soybean peel and wheat bran, improve the nutritive value of the cane silage.

ABSTRACT Our objective was to evaluate performance and fatty acid contents of the meat of Holstein veal fed in feedlots and slaughtered at four different pre-determined live weights (140, 180, 220, and 260 kg). Twenty-three non-castrated calves with initial average ages of 58 days and 57 kg live weight were used in this study. Average daily gain, dry matter intake, nutrient intake, cold carcass weight, cold carcass yield, scraps, and fat thickness improved with increasing slaughter weight. However, C18:0, C22:0, C18:2Trans10Cis12, C18:1n9Cis acids, sum of unsaturated fatty acids, and lipid content decreased with the increase in slaughter weight. Raising the slaughter weight of Holstein calves from 144 to 260 kg improves the performance of animals, mainly due to the increase in their intake capacity. However, this increase in slaughter weight does not result in significant changes in the fatty acid composition of the meat.

RESUMO: O objetivo deste trabalho foi avaliar o efeito da espessura de gordura subcutânea (EGS) nas características de carcaça e qualidade de carne em novilhos, com até 24 meses de idade, britânicos ou suas cruzas terminados no sistema de confinamento. Para isso foi utilizado o sistema de meta-análise com dados extraídos de 46 artigos publicados, totalizando 2,695 unidades experimentais. Foi encontrado que a GS influencia no aumento linear no peso de carcaça quente (PCC) e fria (PCF) e em seus rendimentos. Além disso as frações de osso decaem enquanto as frações de músculo e gordura aumentam em altos níveis de GS. Não foi encontrada diferença significativa, mas variáveis de qualidade de carne. Assim a GS apresenta influência direta em PCC, PCF e nos pesos e rendimento de osso, músculo e gordura da carcaça de novilhos castrados. Um valor uniforme de gordura subcutânea de 6,00 mm é capaz de padronizar uma qualidade de carcaça e de produtos aos consumidores.

ABSTRACT: The objective of this research was to examine the effect of subcutaneous fat thickness (SFT) on carcass characteristics and meat quality in 24-month-old British and crossbred British steers finished in feedlot systems. It was assessed using meta-analysis performed on data that was extracted from 46 published studies and comprising a total of 2,695 experimental units. We found that SFT was influenced by and increased linearly with hot carcass weights (HCWs) and cold carcass weights (CCWs) and their yields; moreover, the bone fraction decreased whereas the muscle and fat fractions increased with higher levels of SFT. No significant differences were detected in meat quality variables. Thus, SFT appeared to have a direct influence on HCW, CCW, and the weight and yield of bone, muscle, and fat of castrated steers. A uniform fat thickness level of 6.0 mm SFT was determined to be the standard of quality of carcasses and meat products for consumers.

Resumo O objetivo deste trabalho foi avaliar a eficiência biológica do sucedâneo em substituição ao leite, na fase de cria e recria de bezerros da raça Holandesa. O trabalho foi realizado na Universidade Tecnológica Federal do Paraná (UTFPR), Dois Vizinhos, entre maio de 2011 e abril de 2012. A pesquisa foi realizada com 32 animais, adotando-se o delineamento inteiramente casualizado com quatro tratamentos e oito repetições: 100% leite; 34% sucedâneo + 66% leite; 66% sucedâneo + 34% leite; e 100% sucedâneo. Os dados foram submetidos à analise de variância e de regressão a 5% de significância. Dentre as medidas morfométricas realizadas, apenas o ganho de perímetro torácico apresentou diferença significativa. A utilização de sucedâneo em substituição ao leite durante a fase de aleitamento apresentou uma resposta linear negativa para os níveis 100%, 66%, 34% sucedâneo, porém durante a fase de recria ocorreu um ganho compensatório dos animais submetidos aos tratamentos 34% e 66% sucedâneo. A utilização de 100% de sucedâneo na alimentação de bezerros holandeses na fase de cria não foi eficiente durante o aleitamento. Durante a fase de recria, a substituição parcial do leite por sucedâneo (66% sucedâneo + 34% leite) mostrou ser a opção mais eficiente, pois apresentou um ganho compensatório favorável.

Abstract The objective of this study was to evaluate the biological efficiency of the milk replacer in the substitution of whole milk for calves at the first months of age and at rearing fase. This study was conducted in Universidade Tecnológica Federal do Paraná (UTFPR), Campus Dois Vizinhos, from May 2011 to April 2012. This research was carried out on 32 animals, assigned in a completely randomized design with four treatments (100% whole milk, 34% milk replacer + 66% whole milk, 66% milk replacer + 34% whole milk and 100% milk replacer) and eight replications.The data were analyzed by analysis of variance and regression at 5% of significance. Regarding the morphometric measurements, only the gain of chest circumference presented significant difference. The use of milk replacer in the substitution of whole milk during pre-weaning phase showed negative linear response for levels 100%, 66%, 34% milk replacer, nevertheless during the post-weaning phase there was a compensatory gain for the animals fed with 34% and 66 % milk replacer. The use of 100% milk replacer for Holstein calves at pre-weaning phase was not efficient during lactation, althoug, during post-weaning phase, partial replacement of milk by milk replacer (66% + 34% milk replacer) was an efficient option because there was a favorable compensatory growth.

O objetivo deste experimento foi avaliar as características da carcaça de bezerros holandeses terminados em confinamento ou em pastagem com suplementação e abatidos com diferentes pesos de abate. Os animais confinados foram alimentados com volumoso e concentrado comercial, na proporção de 40:60, sendo a silagem de milho utilizada como volumoso. O delineamento experimental foi o inteiramente casualizado, em arranjo fatorial 2x4 (dois sistemas de terminação x quatro pesos de abate). Os animais foram abatidos à medida que atingiam os pesos de abate pré-determinados (140, 180, 220 e 260kg). O sistema de acabamento não teve influência sobre o peso e rendimento de carcaça quente e fria e as perdas de carcaça, mas os animais confinados apresentaram maior espessura de gordura. Animais confinados apresentaram melhor conformação, comparados com os terminados em pastagem. À medida que aumentou o peso de abate, houve crescimento linear para peso de carcaça quente e fria, rendimento de carcaça quente e fria, conformação, medidas métricas e peso dos cortes comerciais da carcaça. O percentual do corte traseiro decresceu com o aumento do peso de abate, enquanto que a espessura de gordura apresentou resposta quadrática. Os sistemas de abate apresentaram rendimento de carcaça semelhante. As características da carcaça melhoram com o aumento do peso de abate, mas, em percentagem, são semelhantes

Objetivou-se avaliar o comportamento ingestivo de bezerros Holandeses mantidos em dois sistemas de criação: confinamento ou a pasto. Foi observado o comportamento ingestivo de 11 bezerros machos, não castrados, com idade média inicial de 75 dias, sendo que seis foram confinados individualmente, consumindo dieta a base de silagem de milho e concentrado na proporção de 40:60 (com base na MS), e o restante, em pastagem de milheto (Pennisetum americanum) recebendo suplementação concentrada ao nível de 1,0% do peso vivo. As avaliações foram realizadas nos meses de novembro a fevereiro, das 8h às 18h. Bezerros confinados permanecem mais tempo (p < 0,05) em ócio, tanto na posição deitado, quanto em pé, enquanto que os animais a pasto permaneceram mais tempo em atividade de alimentação e ruminação. Animais confinados realizaram maior número de refeições diárias, porém de menor duração cada. Em ambos sistemas de criação, a atividade de ruminação é realizada preferencialmente na posição deitada, no entanto, o tempo de ruminação em pé é cerca de 1,4 vezes maior para os mantidos em pastagem. Animais mantidos em pastagem apresentam menor eficiência de ingestão de MS, maior número de bolos ruminados, sendo estes, ruminados em menor tempo e com menor número de mastigadas meríciclas.

This study evaluated the ingestive behavior of Hostein calves kept in two husbandry systems: feedlot or pasture. We examined the ingestive behavior of 11 male non-castrated calves, with average initial age of 75 days, six of which were individually penned, consuming corn silage and concentrate-based diet at a ratio of 40:60 (on a DM basis), and the remainder, on pearl millet pasture (Pennisetum americanum) receiving concentrate supplementation at 1.0% body weight. Evaluations were held from November to February, from 8:00 am to 6:00 pm. Feedlot calves stay longer (p < 0.05) in idle, both in lying and standing positions, while animals on pasture spent more time in eating and ruminating activities. Confined animals performed a higher number of daily meals, but of shorter duration each. In both production systems, rumination activity is preferably performed in lying position, however, rumination time in standing position is about 1.4 times longer for those kept on pasture. Animals kept on pasture show a lower efficiency of DM intake, greater number of ruminated boluses, which were ruminated for less time and with fewer cud chewings.

O objetivo deste estudo foi avaliar os órgãos internos e o trato digestório de novilhos e vacas de descarte 5/8 Charolês (Ch) 3/8 Nelore (Ne) e 5/8Ne 3/8Ch, terminados em confinamento. Foram utilizados 12 novilhos e 12 vacas de descarte, sendo cada categoria composta por seis animais 5/8Ch 3/8Ne e seis animais 5/8Ne 3/8Ch. A idade média dos animais ao final do período experimental foi de 23 meses para os novilhos e 68 meses para as vacas de descarte. Os animais foram terminados em confinamento até atingirem acabamento para o abate. A dieta alimentar continha relação volumoso:concentrado de 40:60 (base na matéria seca). O delineamento experimental foi o inteiramente casualizado, em um arranjo fatorial 2 x 2 (2 categorias x 2 grupos genéticos. Os dados foram submetidos à análise de variância pelo proc GLM, sendo as médias classificadas pelo teste "F" e os parâmetros com efeito significativo para interação entre categoria e grupo genético comparados pelo "teste t", a 5% de significância. Houve maior peso de abate (PAB) (509,67 contra 414,50 kg) e de corpo vazio (PCVZ) (433,01 contra 355,27 kg, respectivamente) para as vacas em relação aos novilhos. As vacas apresentaram maiores pesos absolutos para coração (1,62 contra 1,40 kg), fígado (7,07 contra 5,95 kg) e também para o conjunto de órgãos internos, total do trato digestório e sangue. Quando os pesos dos componentes foram expressos em porcentagem do PCVZ, os novilhos foram superiores no peso dos pulmões (1,08 contra 0,95%), baço (0,29 contra 0,22%), intestinos (2,04 contra 1,72%) e no total dos órgãos vitais (3,92 contra 3,63%). Quanto aos grupos genéticos, animais 5/8Ch 3/8Ne apresentaram maior peso absoluto de trato digestório. Não houve correlação entre o rendimento de carcaça com componentes não integrantes da carcaça expressos em peso absoluto. Vacas de descarte apresentam maior massa dos órgãos internos e do trato digestório que novilhos abatidos aos 24 meses, enquanto bovinos do grupo genético 5/8Ch 3/8Ne apresentam maior peso de compartimentos e do total do trato digestório em relação a bovinos 5/8Ne 3/8Ch.

The objective of this study was to evaluate the internal organs and digestive tract of two categories, steers and cull cows, from two genetic groups: 5/8 Charolais (Ch) 3/8 Nellore (Ne) and 5/8Ne 3/8Ch, finished in feedlot. We used 12 steers and 12 cull cows, being the categories compounded for six 5/8Ch 3/8Ne animals and six animals 5/8Ne 3/8Ch. The average age of animals at the end of the experimental period was 23 and 68 months for steers and cull cows, respectively. The animals were feedlot-finished until reaching finishing degree for slaughter. The experimental diet had a roughage:concentrate ratio of 40:60 (dry matter basis). The experimental design was completely randomized in a 2 x 2 (two categories and two genetic groups) factorial scheme. Data were submitted to analysis of variance by proc GLM, being the means classified by test "F" and the parameters with significant effects for interaction between genetic group and category compared by "test t", with 5% significance level. Slaughter weight (SW) (509.67 versus 414.50kg) and empty body weight (EBW) (433.01 versus 355.27kg, respectively) were higher for cows in relation to steers. The cull cows showed higher absolute weight for heart (1.62 versus 1.40 kg), liver (7.07 versus 5.95 kg) and for total internal organs, digestive tract and blood. When the components were adjusted for percentage of EBW the steers were superiors on lungs (1.08 versus 0.95%), spleen (0.29 versus 0.22%) intestines (2.04 versus 1.70%) and total internal organs weight (3.91 versus 3.60%). As genetic groups, 5/8Ch 3/8Ne animals showed higher absolute weight for digestive tract. The carcass dressing percentage and non-carcass components, in absolute weight, showed correlation. Cull cows showed higher weight for internal organs and digestive tract than steers slaughtered at 24 months, while cattle for genetic group 5/8Ch 3/8Ne showed higher weight for compartments and total of digestive tract in relation to 5/8Ne 3/8Ch bovines.

A disponibilização anual de genótipos de milho é grande, sendo necessária uma adequada avaliação desses genótipos para serem indicados para a produção de silagem. Objetivou-se avaliar as características bromatológicas da silagem produzida a partir de diferentes genótipos de milho, bem como, avaliar se a base genética ou a dureza dos grãos podem alterar a indicação de genótipos de milho para silagem. O experimento foi realizado na área experimental da Universidade Tecnológica Federal do Paraná, no delineamento blocos completos ao acaso, avaliando-se os 30 genótipos do ensaio Sul Super Precoce, organizado pela Embrapa. Avaliaram-se as características bromatológicas da silagem produzida com os diferentes genótipos, posteriormente eles foram agrupados segundo a base genética e a textura dos grãos. Verificou-se que os genótipos do ensaio Sul Super Precoce não podem ser diferenciados segundo a base genética ou a textura dos grãos para todas as características avaliadas. Porém, eles podem ser diferenciados pela matéria seca da silagem.

The annual availability of corn genotype is very large, requiring a proper assessment to be indicated for the production of silage. The aim of this study was to evaluate the chemical characteristics of corn genotypes for silage production, and assess whether the grain genetic basis or hardness may change the indication of corn cultivars for silage. The experiment was conducted at the experimental area of the Universidade Tecnológica Federal of Paraná, in the randomized block design, evaluating 30 genotypes of experiment Super Early South. It was evaluated the chemical characteristics of the genotypes and, after they were grouped according to the characteristics of genetic basis and of grain texture. It was found that the genotypes of the experiment South Super Early cannot be differentiated according to the genetic basis of grain and texture for all traits. However, they can be distinguished by the dry matter silage.