Carcass, meat quality traits, and economic analysis of Nellore bulls fed with finishing feedlot diets containing mechanically processed corn silage.

Effects of mechanical processing (MP) of corn silage and its inclusion in feedlot diets on carcass and meat quality traits of Nellore (Bos indicus) were analyzed. Seventy-two bulls aged approximately 18 months and with an initial average body weight of 392.8 ± 22.3 kg were used. The experimental design was a 2 × 2 factorial arrangement, considering the concentrate-roughage (C:R) ratio (40:60 or 20:80), MP of silage and their interactions. After slaughter, hot carcass weight (HCW), pH, temperature, backfat thickness (BFT), and ribeye area (REA), yields of meat cuts (tenderloin, striploin, ribeye steak, neck steak, and sirloin cap), meat quality traits and economic analysis were evaluated. A lower final pH was found in the carcasses of animals consuming diets containing MP versus unprocessed silage (pH = 5.81 versus 5.93). Carcass variables (HCW, BFT, and REA) and meat cut yields were not affected by treatments. The C:R 20:80 increased the intramuscular fat (IMF) content by approximately 1%, without affecting moisture, ash, and protein contents. Meat/fat color (L*, a* and b*) and Warner-Bratzler shear force (WBSF) were similar among treatments. The results indicated that the MP of corn silage in finishing diets can provide better carcass pH results in Nellore bulls, without negatively influencing carcass weight, fatness, and meat tenderness (WBSF). The IMF content of meat was slightly improved using a C:R 20:80 and lower total costs per arroba produced (3.5%), daily costs per animal/day (4.2%), and cost per ton of feeds (5.15%) were found with MP silage.

Valor nutritivo do capim-xaraés em três intensidades luminosas / Nutritive value of xaraés palisade grass in three light intensities

Este trabalho teve como objetivo avaliar o valor nutritivo e a força de cisalhamento da cultivar de Urochloa brizantha (syn Brachiaria brizantha) cv Xaraés submetida a três intensidades luminosas e quatro cortes. O experimento foi conduzido na FMVZ - Unesp de Botucatu, com delineamento experimental em blocos ao acaso, sendo os tratamentos: luminosidade natural, redução de 30% e 60% de luz, com quatro cortes e três repetições. As análises realizadas foram: composição bromatológica, digestibilidade e a força de cisalhamento. Não houve diferença na digestibilidade entre os tratamentos em nenhum dos cortes, mas a qualidade forrageira foi influenciada pelos níveis de intensidade de luz, tendo o tratamento com 60% de redução de luminosidade apresentado maiores concentrações de proteína bruta e cinzas, menores teores de fibra em detergente neutro, hemicelulose, celulose e força de cisalhamento. Em relação aos cortes estudados, o primeiro teve o menor intervalo de corte e produziu forragem com qualidade superior em comparação ao último, pois obteve menor teor de fibra em detergente ácido, lignina, hemicelulose, celulose e consequente menor força de cisalhamento. Portanto, a redução de 60% de luminosidade é benéfica à qualidade e à força de cisalhamento da cultivar Xaraés.(AU)

This study aimed to evaluate the nutritive value and shear strength of the Xaraés grass (Urochloa brizantha) under the three intensities of light and four cuts. The experiment was conducted at FMVZ - UNESP, Botucatu, with a randomized block design, with the following treatments: natural luminosity, 30% and 60% light reduction, with four cuts and three replications. The analyzes were bromatological composition, digestibility, and shearing strength. There was no difference in digestibility between the treatments in any of the cuts, forage quality was influenced by the light intensity levels, and the treatment with 60% of light reduction produced higher concentrations of crude protein and ash, lower levels of neutral detergent fiber, hemicellulose, cellulose and shear strength. According to the studied cuts, the first one had the lowest cut interval and produced superior forage compared with the last one, as it obtained lower fiber content in acid detergent, lignin, hemicellulose, cellulose and consequent lower shear force. Therefore, the reduction of 60% of luminosity is beneficial to the quality and shear force of the Xaraés palisade grass.(AU)

Padrão de deslocamento de bovinos Nelore em sistemas integrados de produção agropecuária / Displacement patterns of Nellore cattle in integrated crop livestock system

The objective of this study was to characterize the displacement patterns of Nellore cattle in areas of crop livestock and crop livestock forest integration systems with density of 196 and 448 eucalyptus ha-1. Paddock maps were drawn from satellite images of the experimental area. In each evaluated system there was one trained observer, that on the paddock map recorded the place the animals stayed every 10 minutes. The exploration of the area by the animals was observed for 12 hours, starting at 6 a.m. and ending at 6 p.m. The displacement of the animals in the ILP system during the evaluation was bigger than the ILPFs systems, resulting in greater exploration of the area, this fact was due the presence of trees that, for the animals resembled fences, limiting the exploration of the paddock in ILPFs. In the ILPF with higher density of trees, this behavior was more evident. In the period from 10:10 a.m. to 14:00 p.m. the displacement of the animals was decrease by the high temperatures in all systems, although it was more effective in the ILP system. It is concluded that the displacement of cattle is influenced by the presence and density of arboreal component integrated crop livestock system.(AU)

In vivo ultrasound and biometric measurements predict the empty body chemical composition in Nellore cattle.

Evaluation of the body chemical composition of beef cattle can only be measured postmortem and those data cannot be used in real production scenarios to adjust nutritional plans. The objective of this study was to develop multiple linear regression equations from in vivo measurements, such as ultrasound parameters [backfat thickness (uBFT, mm), rump fat thickness (uRF, mm), and ribeye area (uLMA, cm2)], shrunk body weight (SBW, kg), age (AG, d), hip height (HH, m), as well as from postmortem measurements (composition of the 9th to 11th rib section) to predict the empty body and carcass chemical composition for Nellore cattle. Thirty-three young bulls were used (339 ± 36.15 kg and 448 ± 17.78 d for initial weight and age, respectively). Empty body chemical composition (protein, fat, water, and ash in kg) was obtained by combining noncarcass and carcass components. Data were analyzed using the PROC REG procedure of SAS software. Mallows' Cp values were close to the ideal value of number of independent variables in the prediction equations plus one. Equations to predict chemical components of both empty body and carcass using in vivo measurements presented higher R2 values than those determined by postmortem measurements. Chemical composition of the empty body using in vivo measurements was predicted with R2 > 0.73. Equations to predict chemical composition of the carcass from in vivo measurements showed R2 lower (R2< 0.68) than observed for empty body, except for the water (R2 = 0.84). The independent variables SBW, uRF, and AG were sufficient to predict the fat, water, energy components of the empty body, whereas for estimation of protein content the uRF, HH, and SBW were satisfactory. For the calculation of the ash, the SBW variable in the equation was sufficient. Chemical compounds from components of the empty body of Nellore cattle can be calculated by the following equations: protein (kg) = 47.92 + 0.18 × SBW - 1.46 × uRF - 30.72 × HH (R2 = 0.94, RMSPE = 1.79); fat (kg) = 11.33 + 0.16 × SBW + 2.09 × uRF - 0.06 × AG (R2 = 0.74, RMSPE = 4.18); water (kg) = - 34.00 + 0.55 × SBW + 0.10 × AG - 2.34 × uRF (R2 = 0.96, RMSPE = 5.47). In conclusion, the coefficients of determination (for determining the chemical composition of the empty body) of the equations derived from in vivo measures were higher than those of the equations obtained from rib section measurements taken postmortem, and better than coefficients of determination of the equations to predict the chemical composition of the carcass.

Influence of feeding differentiation on the age at onset of puberty in Brazilian Bergamasca dairy ewe lambs / Influência da diferenciação alimentar na idade à puberdade em cordeiras da raça Bergamácia Brasileira

The objective of the study was to evaluate body growth and age at onset of puberty on lambs fed two specific diets for low and high growth rates. A herd of 20 Brazilian Bergamasca lambs was divided in two groups (n= 10) and kept confined throughout the experimental period, two animals of the same treatment/pen. Two phases were established: Phase 1, from 90 days of age until the onset of puberty; and Phase 2, from puberty onset up to 1 year old. For Phase 1, two distinct diets were formulated, being: Treatment A, which was formulated to obtain an average daily gain of approximately 150g; and Treatment B, for an average daily gain of about 250g. In Phase 2, a balanced, equal diet was provided to both groups. Every 14 days, the animals were weighed and given average daily gain, average daily dry matter intake and body condition score. From the 5th month of age on, in each group, a vasectomized male was used to detect estrus, establishing age at puberty onset and estrus interval for each lamb. Blood samples were collected every 28 days to determine plasma growth hormone concentration. Treatment B lambs gained more weight and had higher body condition score (P<0.05) and there was no difference for age at puberty onset and plasma growth hormone levels (P>0.05) between treatments. It was found that both treatments showed satisfactory performances. Thus, treatment A may be indicated as a reasonable feeding system to achieve positive responses on confined ewe lambs during growth phase.

O objetivo do estudo foi avaliar o crescimento corporal e idade de início da puberdade em cordeiras sob duas dietas específicas para taxas de crescimento baixas e altas. Um rebanho de 20 cordeiras Bergamácia Brasileira foi dividido em dois grupos (n= 10) e mantido confinado em todo período experimental, sendo dispostos dois animais do mesmo tratamento/baia. Duas fases foram estabelecidas: Fase 1, a partir de 90 dias de idade até o início da puberdade, e Fase 2, a partir do início da puberdade até 1 ano de idade. Para a fase 1, duas dietas distintas foram formuladas, sendo: Tratamento A, formulada para obter um ganho de peso diário de aproximadamente 150g; e Tratamento B, para um ganho de peso médio diário de cerca de 250g. Na Fase 2, uma dieta equilibrada idêntica foi fornecida para ambos os grupos. A cada 14 dias, os animais foram pesados e calcularam-se o ganho médio diário, o consumo médio diário de matéria seca e escore de condição corporal. A partir do quinto mês de idade, em cada grupo, um macho vasectomizado foi usado para detectar estro, estabelecendo a idade de início da puberdade e estro para cada cordeira. As amostras de sangue foram coletadas a cada 28 dias para determinar a concentração plasmática de hormônio do crescimento. Cordeiras do tratamento B ganharam mais peso e tiveram maior escore de condição corporal (P<0,05), mas não houve diferença de idade para o início da puberdade e para os níveis plasmáticos de hormônio do crescimento (P>0,05). Verificou-se que os tratamentos A e B apresentaram desempenhos satisfatórios. Assim, o tratamento A pode ser indicado como um sistema de alimentação para alcançar respostas positivas em cordeiras submetidas ao confinamento durante a fase de crescimento.

Nutritional value of high moisture corn silage in the diet of Holstein cows / Valor nutritivo da silagem de grãos úmidos de milho na alimentação de vacas da raça Holandesa

Five Holstein cows were distributed in a 5x5 latin square design to assess the effect of replacement levels of dry ground corn grain (DGCG) by high moisture corn silage (HMCS) on intake, total nutrient digestibility and plasma glucose, according to the following treatments: 1) 100% DGCG; 2) 75% DGCG and 25% HMCS; 3) 50% DGCG and 50% HMCS; 4) 25% DGCG and 75% HMCS; 5) 100% HMCS. The experiment lasted 70 days, divided into five phases of 14 days each. The digestibility was obtained using chromic oxide (Cr2O3) as the indicator. Fecal samples were collected twice daily and blood samples were collected on the last day of each period before the first meal (0h) and 2h, 4h, 6h and 12h after the meal. There was no effect (P>0.05) on the intake of dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF) and starch. The total apparent digestibility of DM, crude protein (CP), NDF and ADF were not affected (P>0.05) by the treatments, as well as the plasma glucose concentration. However, there was a decreased linear effect (P<0.05) for the protein intake and increased linear effect (P<0.05) for starch digestibility, as the level of HMCS was increased in the diets...

Cinco vacas da raça Holandesa foram distribuídas em quadrado latino 5x5 com o objetivo de se avaliar o efeito de níveis de substituição do grão seco de milho (GSM) pela silagem de grãos úmidos de milho (SGUM) sobre consumo, digestibilidade total dos nutrientes e glicose plasmática, o que constituiu os tratamentos: 1) 100% GSM; 2) 75% GSM e 25% SGUM; 3) 50% GSM e 50% SGUM; 4) 25% GSM e 75% SGUM; 5) 100% SGUM. O período experimental durou 70 dias, divididos em cinco fases de 14 dias. A digestibilidade foi obtida utilizando-se óxido crômico (Cr2O3) como indicador. Foram colhidas amostras fecais duas vezes por dia, bem como amostras de sangue no último dia dos períodos, antes da primeira refeição (zero hora), duas, quatro, seis e 12 horas após a refeição. Não houve efeito (P>0,05) sobre o consumo de matéria seca (MS), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e amido. A digestibilidade aparente total da MS, a proteína bruta (PB), a FDN e a FDA não foram afetadas (P>0,05), assim como a concentração de glicose plasmática. Houve efeito linear decrescente (P<0,05) para consumo de PB e linear crescente (P<0,05) para digestibilidade do amido, à medida que se aumentou a inclusão de SGUM...

Capacidade funcional em cavalos de salto suplementados com linhaça / Functional capacity of jumping horses supplemented with linseed

Objetivou-se avaliar a suplementação com linhaça, como fonte do ácido graxo ômega-3, sobre a capacidade funcional de cavalos de salto. Foram utilizados seis equinos distribuídos em dois quadrados latinos 3x3 balanceados. Os grupos experimentais consistiram em níveis crescentes de linhaça (na forma de farinha e óleo de linhaça na proporção de 75:25, respectivamente), resultando nos tratamentos de 0 (controle), 60 e 120g/cavalo/dia de linhaça. Os cavalos foram suplementados por período de 30 dias. A atividade física consistiu em trabalho para salto no nível de equitação fundamental. As variáveis funcionais mensuradas foram índice de claudicação (IC), comprimento da passada e biometria da articulação metacarpofalangeana - MCF (circunferência e ângulo de flexão). Observou-se efeito significativo da suplementação com linhaça, independentemente da dosagem, sobre o IC. Ainda, o fornecimento de 120g de linhaça/cavalo/dia aumentou o comprimento da passada dos cavalos ao trote (P<0,05) e promoveu redução de 0,5cm na circunferência da articulação MCF (P<0,05) em comparação ao grupo controle. A suplementação de cavalos de salto com 120g/dia de linhaça promoveu maior comprimento da passada ao trote e redução de edema na articulação metacarpofalangeana, melhorando suas capacidades funcionais...

The objective of this study was to evaluate the supplementation of linseed as an omega-3 fatty acid supplier on the functional capacity of jumping horses. 6 horses disposed in two 3 x 3 balanced Latin squares were used. The treatments consisted of increasing levels of linseed mixed with flour and linseed oil in a ratio of 75:25, respectively, resulting in 0g (control), 60g and 120g on a daily basis per horse. The horses were supplemented for 30 days. Physical activity was jumping at riding class level. The functional parameters measured were lameness index, stride length and joint metacarpophalangeal (MCP) biometry (circumference and flexion angle). A significant linseed supplementation effect for doses of 60 and 120g was observed on the lameness index. Feeding 120g of linseed increased stride length while trotting (P<0.05). An increment of 0.5cm on MCP circumference was found in horses that received the control diet when compared to those horses that consumed 120g of linseed. Thus, supplementation of jumping horses with 120g/day of linseed promoted greater stride length at a trot and reduced swelling in the metacarpophalangeal joint, improving their functional capabilities...