The objective was to assess agronomic characteristics of sorghum genotypes and nutritional values of produced silage. A total of 15 sorghum genotypes were used. Planting was carried out through a randomized-block design with three replications per genotype, totaling forty-five (45) plots. Agronomic and nutritional characteristics, besides the quality of the silage, were assessed. There were differences between genotypes for all characteristics analyzed, with the exception of levels of acid detergent unavailable nitrogen (ADUN), acid detergent unavailable protein (ADUP) and water activity (aw). The assessment of the parameters, except for genotypes 1016013, 1016025, 1016037, 1016039, Volumax and BRS 610, which presented protein level below 7%, showed that the other genotypes can be used for silage production, since they have a good profile of fermentation and in vitro dry matter digestibility; however, genotype SF15 is the most favorable one for silage production due to its little participation in the neutral detergent fiber fraction.

The objective was to select sorghum genotypes for silage production using its chemical characteristics. The experiment was carried out in the facilities of Embrapa Maize and Sorghum in Sete Lagoas, state of Minas Gerais, to evaluate the agronomic characteristics, and nutritional quality of silage of twelve sorghum genotypes. We used a randomized block design with three replications. In relation to the production of green matter, the genotypes SF15 Volumax and BR610 stood out (52.07; 48.00 and 41.87 ton ha-1). Regarding pH, genotypes 1015339, 1015347, 1016007, SF15, BRS655, Volumax and BR610 averaged 3.68. All genotypes were similar considering the nutritional value, ammonia nitrogen and water activity. The genotypes SF15, Volumax and BRS610 showed the highest productivity per area, representing the best options for silage production.

ABSTRACT. This study evaluated the nutritional characteristics of hay of nineteen hybrids between sorghum and Sudan grass. The experimental design was a randomized block with nineteen treatments and three replications. The chemical characteristics of the respective hays were analyzed 52 days after sowing and 45 and 49 regrowth days. Data were analyzed by analysis of variance, and when the F test was significant, the treatment means were compared by the Scott and Knott test at 5%. Genotypes 1013026 and 1014020 showed similar dry matter content. As for ether extract content, the highest values ranged from 2.20 to 2.66%. Higher values of minerals were observed in hybrids 1013026 and 1011005. In relation to crude protein, higher content values were reported for hybrids 1013021 and 1013020 (14.59 and 15.47% CP). When evaluating the neutral detergent fiber content, lower values varied between 56.05 and 57.07% for hybrids 1013016 and 1011009. Considering the content of acid detergent fiber, values ranged from 32.70 to 35.78%. Values of dry matter digestibility were higher than 50%. All hybrids provide quality hay, however the hybrid 1014019 showed the best nutritional value.

ABSTRACT. This study aimed to evaluate the nutritional characteristics and quality of silages of five sorghum genotypes, namely: Volumax, AG2005E, Qualimax, BRS610 and AG2501. The study was conducted at the Experimental Farm Unimontes, in the municipality of Janaúba, state of Minas Gerais. The treatments were distributed in a randomized block design with four replicates. Data were tested by analysis of variance and means were compared by Scott-Knott test at a significance level of 5%. The pH values ranged from 3.93 and 4.10. Genotypes differed in all studied nutritional characteristics (p < 0.05). For the acid detergent fiber, differences were detected between the genotypes, AG2501 (35.66%), Volumax (34.89%), AG2005E (34.53%), Qualimax (32.39%) and BRS610 (33.60%). The high participation of lignin was verified in all genotypes except for Volumax (4.14%). All silages were within the recommended range 50-65% for in vitro dry matter digestibility and classified as having good quality, however only the AG2005E genotype met nitrogen requirements for microbial fermentation, with 7.06% crude protein.

This study aimed to evaluate in situ degradability and degradation kinetics of DM, NDF and ADF of silage, with or without tannin in the grains. Two isogenic lines of grain sorghum (CMS-XS 114 with tannin and CMS-XS 165 without tannin) and two sorghum hybrids (BR-700 dual purpose with tannin and BR-601 forage without tannin) were ensiled; dried and ground silage samples were placed in nylon bags and introduced through the fistulas. After incubation for 6, 12, 24, 48, 72 and 96 hours, bags were taken for subsequent analysis of fibrous fractions. The experimental design was completely randomized with 4 replicates and 4 treatments and means compared by Tukey's test at 5% probability. As for the DM degradation rate, silage of CMS-XS 165 without tannin was superior. Silages of genotypes BR 700 and CMS-XS 114 with tannin showed the highest values of indigestible ADF (59.54 and 43.09%). Regarding the NDF, the potential degradation of silage of CMS-XS165 line without tannin was superior. Tannin can reduce ruminal degradability of the dry matter and fibrous fractions.Degrabilidade in situ da matéria seca e fração fibrosa da silagem de sorgo RESUMO. Objetivou-se avaliar a degradabilidade in situ e a cinética de degradação da MS, FDN e FDA das silagens, com presença e ausência de tanino nos grãos. Foram utilizadas, duas linhagens isogênicas de sorgo granífero (CMS-XS 114 com tanino e CMS-XS 165 sem tanino) e dois híbridos de sorgo (BR-700 duplo propósito com tanino e BR-601 forrageiro sem tanino). Amostras de silagens secas e moídas foram colocadas em sacos de náilon e introduzidas nas fístulas dos bovinos. Após períodos de incubação de 6, 12, 24, 48, 72 e 96 h, os sacos foram removidos para análises posteriores das frações fibrosas. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repetições e quatro tratamentos e as médias comparadas pelo teste de Tukey em nível de 5% de significância. Quanto à taxa de degradação da MS, a silagem da linhagem CM-SXS 165 sem tanino foi superior. As silagens dos genótipos BR 700 e CMS-XS 114 com tanino apresentaram os maiores valores de fração indigestível da fração FDA (59,54 e 43,09%). Para a FDN, observou-se que o potencial de degradação da silagem da linhagem CMS-XS 165 sem tanino foi superior. A presença do tanino pode reduzir a degradabilidade ruminal, da matéria seca e das frações fibrosas.Palavras-chave: alimento conservado, forragem, tanino, valor nutricional.License information: This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Ŷ =35.8463 (1-e 0.04*t ); R 2 = 0.9970 Ŷ = 71.5607 (1-e 0.01*t ); R 2 = 0.9780 Ŷ = 50.0286 (1-e 0.02*t ); R 2 = 0.9750 Ŷ = 59.4826 (1-e 0.02*t ); R 2 = 0.9940