A comparison of the economic results obtained by Holstein steer calves with different feedlot arrival body weights / Uma comparação dos resultados econômicos obtidos por bezerros Holstein com diferentes pesos vivos na entrada do confinamento

ABSTRACT: The study compared the economic results between five groups of Holstein steers with different arrival body weights (ABW) but similar ages in the feedlot. The average ABW were 105, 112, 117, 123 and 129 kg (30, 90, 87, 60, and 30 calves, respectively) with an age of 113 ± 1d. The calves were randomly distributed using an unbalanced design. The calves were weighed upon arrival at the feedlot and subsequently on days 112, 224, and 361 of the study. The calves were fed a steam- flaked corn-based diets. A receiving diet (2.21 Mcal of NEm/kg DM) was provided during the initial 112 days of feeding. From day 112 until harvest all steers received a finishing diet (2.27 Mcal of NEm/kg DM). Because two different diets were used, two partial (day 1 to day 112 and day 113 to day 361), and one full period (day1 to day 361) feeding periods were evaluated. Statistical differences between the final weights of all the groups were observed, which allowed a profit estimation, obtained by subtracting the purchase cost of calves plus the total feed cost from the revenue obtained from the sale of the steers. Overall weight gain and feed intake were higher with increased ABW, feeding efficiency was better for intermediate ABW groups (112 and 117 kg), with the calves with ABW of 112 kg being the most profitable (USD 15.8 more profit than the 117 Kg. group)

RESUMO: O estudo comparou os resultados econômicos entre cinco grupos de bezerros de raça holandesa com pesos vivos de chegada diferente, mas com idades semelhante em confinamento. Os pesos corporais médios de chegada foram 105, 112, 123 e 129 kg (30, 90, 87, 60 e 30 bezerros, respectivamente) com idade de 113 ± 1-d. Os bezerros foram distribuídos em um desenho não balanceado completamente aleatório. Os bezerros foram pesados da chegada ao confinamento e, posteriormente, nos dias 112, 22 e 361 do estudo. Os bezerros foram alimentados com dietas à base de milho floculado. A dieta de adaptação (2,21 Mcal de NEm / kg MS) foi fornecida durante os 112 dias iniciais de ração. Após 112 até o final do estudo todos os novilhos receberam a dieta de terminação (2,27 Mcal de NEm /kg MS). Diante do exposto, foram avaliados dois períodos parciais de alimentação e um período completo (1 a 112, 113 a 361 e 1 a 361 d, respectivamente). O lucro de cada grupo foi estimado subtraindo o custo de compra dos bezerros mais o custo total da alimentação da receita obtida com a venda dos novilhos. O ganho de peso geral e o consumo de ração aumentaram com o aumento do ABW, mas a eficiência alimentar foi melhor para os grupos intermediários ABW (112 e 117 kg), sendo os novilhos com ABW de 112 kg os mais lucrativos (USD 15, 8 a mais do que o grupo de 117 kg.)

A comparison of the economic results obtained by Holstein steer calves with different feedlot arrival body weights / Uma comparação dos resultados econômicos obtidos por bezerros Holstein com diferentes pesos vivos na entrada do confinamento

The study compared the economic results between five groups of Holstein steers with different arrival body weights (ABW) but similar ages in the feedlot. The average ABW were 105, 112, 117, 123 and 129 kg (30, 90, 87, 60, and 30 calves, respectively) with an age of 113 ± 1d. The calves were randomly distributed using an unbalanced design. The calves were weighed upon arrival at the feedlot and subsequently on days 112, 224, and 361 of the study. The calves were fed a steam- flaked corn-based diets. A receiving diet (2.21 Mcal of NEm/kg DM) was provided during the initial 112 days of feeding. From day 112 until harvest all steers received a finishing diet (2.27 Mcal of NEm/kg DM). Because two different diets were used, two partial (day 1 to day 112 and day 113 to day 361), and one full period (day1 to day 361) feeding periods were evaluated. Statistical differences between the final weights of all the groups were observed, which allowed a profit estimation, obtained by subtracting the purchase cost of calves plus the total feed cost from the revenue obtained from the sale of the steers. Overall weight gain and feed intake were higher with increased ABW, feeding efficiency was better for intermediate ABW groups (112 and 117 kg), with the calves with ABW of 112 kg being the most profitable (USD 15.8 more profit than the 117 Kg. group)

O estudo comparou os resultados econômicos entre cinco grupos de bezerros de raça holandesa com pesos vivos de chegada diferente, mas com idades semelhante em confinamento. Os pesos corporais médios de chegada foram 105, 112, 123 e 129 kg (30, 90, 87, 60 e 30 bezerros, respectivamente) com idade de 113 ± 1-d. Os bezerros foram distribuídos em um desenho não balanceado completamente aleatório. Os bezerros foram pesados da chegada ao confinamento e, posteriormente, nos dias 112, 22 e 361 do estudo. Os bezerros foram alimentados com dietas à base de milho floculado. A dieta de adaptação (2,21 Mcal de NEm / kg MS) foi fornecida durante os 112 dias iniciais de ração. Após 112 até o final do estudo todos os novilhos receberam a dieta de terminação (2,27 Mcal de NEm /kg MS). Diante do exposto, foram avaliados dois períodos parciais de alimentação e um período completo (1 a 112, 113 a 361 e 1 a 361 d, respectivamente). O lucro de cada grupo foi estimado subtraindo o custo de compra dos bezerros mais o custo total da alimentação da receita obtida com a venda dos novilhos. O ganho de peso geral e o consumo de ração aumentaram com o aumento do ABW, mas a eficiência alimentar foi melhor para os grupos intermediários ABW (112 e 117 kg), sendo os novilhos com ABW de 112 kg os mais lucrativos (USD 15, 8 a mais do que o grupo de 117 kg.)

Digestion and energy value of macerated sudangrass hay used in growing-finishing diets for feedlot cattle

Mechanical maceration enhances site and extent of digestion of low-moisture, low-quality forages. Four Holstein steers (172 ± 8 kg) with cannulas in rumen and proximal duodenum were used in 4x4 Latin square design to evaluate the process of mechanical maceration of sudangrass hay on the characteristics of ruminal and total tract digestion. Treatments consisted of a steam-flaked corn-based growing diet supplemented with 21 % forage (DM basis) as: i) wheat straw (Triticum aestivum, STRW), ii) sudangrass hay (Sorghum sudanense, SG), iii) macerated SG at intensity of 4,134 kPa (MAC600) and 4) macerated SG at intensity of 6,200 kPa (MAC900). All forages were ground to pass through a 3.8 cm screen before incorporation into complete mixed diets (21:79 forage to concentrate ratio). Maceration did not affect (p 0.17) on site and extent of OM, N and ADF, and DE of sudangrass supplemented diets. Characteristics of ruminal digestion of OM, ADF, starch, as well as, microbial efficiency (microbial N, g kg-1 of OM fermentad) and protein efficiency (nonammonia N, g g-1 of N intake) were not different (p 0.11) for wheat straw versus sudangrass supplemented diets. However, total tract digestion of OM, ADF, N, and DE diet were greater (p 0.05) for sudangrass than for wheat straw supplemented diets. Using the replacement technique, DE value of SG averaged 9.59 MJ kg-1, very close to the expected value given its chemical composition. Mechanical maceration did not enhance the feeding value of sudangrass hay. Increase the intensity of maceration from 4,134 to 6,200 kPa did not altered ruminal or total tract digestion of OM, NDF or energy value of processed hay

Digestion and energy value of macerated sudangrass hay used in growing-finishing diets for feedlot cattle

Mechanical maceration enhances site and extent of digestion of low-moisture, low-quality forages. Four Holstein steers (172 ± 8 kg) with cannulas in rumen and proximal duodenum were used in 4x4 Latin square design to evaluate the process of mechanical maceration of sudangrass hay on the characteristics of ruminal and total tract digestion. Treatments consisted of a steam-flaked corn-based growing diet supplemented with 21 % forage (DM basis) as: i) wheat straw (Triticum aestivum, STRW), ii) sudangrass hay (Sorghum sudanense, SG), iii) macerated SG at intensity of 4,134 kPa (MAC600) and 4) macerated SG at intensity of 6,200 kPa (MAC900). All forages were ground to pass through a 3.8 cm screen before incorporation into complete mixed diets (21:79 forage to concentrate ratio). Maceration did not affect (p 0.17) on site and extent of OM, N and ADF, and DE of sudangrass supplemented diets. Characteristics of ruminal digestion of OM, ADF, starch, as well as, microbial efficiency (microbial N, g kg-1 of OM fermentad) and protein efficiency (nonammonia N, g g-1 of N intake) were not different (p 0.11) for wheat straw versus sudangrass supplemented diets. However, total tract digestion of OM, ADF, N, and DE diet were greater (p 0.05) for sudangrass than for wheat straw supplemented diets. Using the replacement technique, DE value of SG averaged 9.59 MJ kg-1, very close to the expected value given its chemical composition. Mechanical maceration did not enhance the feeding value of sudangrass hay. Increase the intensity of maceration from 4,134 to 6,200 kPa did not altered ruminal or total tract digestion of OM, NDF or energy value of processed hay