ABSTRACT. The objective of this study was to evaluate the fermentation profile and nutritional value of Marandu grass silage (Urochloa brizantha (Hoschst.Ex. A. Rich) R. D. Webster cv. Marandu Syn. Brachiaria brizantha (Hochst. Ex A. Rich) Stapf cv. Marandu} with different levels of inclusion of dehydrated banana peel. The experiment was conducted in a completely randomized design with marandu grass with five levels of dehydrated banana peel (0, 10, 20, 30 and 40% of natural matter) with eight replicates. The data collected were submitted to analysis of variance and, when the "F" test was significant, the inclusion levels of the pre-dried banana peel were analyzed utilizing orthogonal polynomials and linear and quadratic regression models. The mean values of N-NH3 were adjusted to the linear regression model (p < 0.01), while the pH values had the lowest value of 4.3 with the inclusion of 15% of banana peel. The mean values of the gas loss (PG, P = 0.01) and the dry matter recovery (RMS; P = 0.01) were adjusted to the quadratic regression model, with a minimum point of 16.15% for losses and 21% as the maximum point for dry matter recovery. The rate of degradation potential degradability of the dry matter (SD; P = 0.74) did not vary with the inclusion of the banana peel. The potential degradability standardized at 2, 5 and 8% was adjusted to the regressive linear regression model (p < 0.01), and for each percentage point of inclusion of the banana peel, there was a reduction of 0.23, 0.14 and 0.10%, respectively. The inclusion of 10 to 20% dehydrated banana peel in the marandu grass silage improves the fermentation profile and the nutritional value of the silage. ABSTRACT Urochloa Hoschst.Ex. HoschstEx Hoschst (Hoschst.Ex A Rich R D cv Syn Hochst. Hochst (Hochst 0, 0 (0 20 3 40 replicates F "F significant predried pre dried models NNH3 NNH N NH3 NH N-NH p 0.01, 001 0.01 , 01 43 4 4. 15 PG, PG (PG RMS (RMS 1615 16 16.15 21 SD (SD 0.74 074 74 2 8 023 23 0.23 014 14 0.1 010 0.10% respectively 1 Hoschst.Ex ( 00 0.0 161 16.1 0.7 07 7 02 0.2 0. 0.10 16.

ABSTRACT The objective of this study was to evaluate the effects of wilting times and application of an enzymatic-bacterial inoculant on the fermentative profile and nutritional characteristics of BRS capiaçu grass silage in a semi-arid region. Four wilting times treatments (control, 6, 24, and 30 h), with or without the addition of an enzymatic-bacterial inoculant, were analyzed as a split-plot completely randomized design with eight replications. Parameters of the rumen degradability test were analyzed using a split-plot completely randomized block design with four replications. There was no interaction between wilting times and inoculant application on pH, ammoniacal nitrogen (NH3-N), and aerobic stability of BRS capiaçu silage. Aerobic stability was reduced by 1.2 h for every 1-h increase in wilting time. Inoculant application reduced the pH values by 2.59% and extended the aerobic stability of the silage by 19 h. There was a significant interaction of wilting times and inoculant application on the levels of malic, succinic, lactic, and acetic acids. Inoculant application increased the contents of dry matter, ash, crude protein, insoluble neutral detergent fiber, and total carbohydrates by 3.63, 6.13, 7.73, 6.39, and 9.97% compared with non-inoculated silages, respectively. Wilting times for up to 30 h and application of enzymatic-bacterial inoculant improves the fermentative profile and chemical composition and reduces dry matter losses of silage of BRS capiaçu grass harvested at 100 days of regrowth.

ABSTRACT The objective was to evaluate the effects of maturity at harvest and row spacing on fermentative profile, aerobic stability, and nutritional value of biomass sorghum (BRS 716) silage. The experiment was conducted using a split-plot completely randomized block design with three row spacings (45, 70, and 90 cm) and four maturities at harvest (70, 100, 130, and 160 days) and eight replications. Polyvinyl chloride silos of known weight measuring 50 cm length and 10 cm diameter were used for silage production. Dry matter and total carbohydrate contents of the silage increased linearly, whereas crude protein and ash decreased linearly with maturity at harvest. Row spacing did not influence pH, ammoniacal nitrogen (N-NH3), gas and effluent losses, and dry matter recovery of silage. The concentrations of malic, succinic, and acetic acids and ethanol responded quadratically to maturity at harvest. The levels of neutral detergent fiber, lignin, and indigestible neutral detergent fiber increased linearly with maturity at harvest. Ruminal degradation kinetics of dry matter of biomass sorghum silage was not influenced by row spacing. BRS 716 biomass sorghum should be planted at 70-cm row spacing and harvested at 160 days for silage production based on fermentative profile, dry matter losses, and nutritional characteristics.

ABSTRACT. The aim of this study was to evaluate the addition of macauba palm cake (Acrocomia aculeata) on the chemical composition, fermentation and aerobic stability of elephant grass silages (Pennisetum purpureum). The experiment was performed in a completely randomized design with four replicates. The treatments were composed of six levels of macauba palm cake (0, 6, 12, 18, 24, 30%) as additive to elephant grass silage. Dry matter and ethereal extract content of the silage increased linearly with the inclusion of the additive. Addition levels of 15.54% would provide 35% of dry mass, and the limit of 7.00% of ethereal extract in the silage could be obtained with 10.47%. The neutral detergent fiber content reduced linearly from 68.97 to 52.59%, but lignin increased linearly from 6.56 to 7.70%. There was a reduction of 0.17% in the ammoniacal nitrogen content for each 1% of cake. The minimum value of dry matter losses (1.33%) was estimated to the inclusion level of 23.70%. The aerobic stability increased with inclusions between 18 and 24% of cake. The use of levels between 10 and 15% of macauba palm cake are sufficient to optimize dry matter and ethereal extract contents of the silages and to provide a high aerobic stability with minimum losses.

ABSTRACT The objective of this study was to evaluate the effect of quantitative feed restriction level on nutrient intake and digestibility, nitrogen balance, efficiency and feeding behavior, and productive performance of F1 Holstein × Zebu cows in late lactation. Sixty F1 Holstein × Zebu cows were used at the stage of late lactation (183.0±17.5 days of lactation) and with initial body weight (BW) of 499±30 kg. The experimental arrangement adopted was the completely randomized design, with five feed restriction levels (3.39, 2.75, 2.50, 2.25, and 2.00% of BW) and twelve cows as replicates for each treatment. The roughage:concentrate ratio was of 75:25 in the total dry matter of the diet. The restriction of dietary supply from 3.39 to 2.0% of BW linearly reduced dry matter intake by 51.74%. The restriction in diet supply linearly increased dry matter digestibility in 13.76%. For each 1% BW restriction in the diet supply for the animals, there was a linear reduction of 3 h in feeding time. Restriction in diet supply of crossbred cows from 3.39 to 2.0% of BW reduced milk production by 24.84%. For each 1% restriction on supply, 2.17 L of milk were not produced. Milk production corrected to 3.5% fat was not altered with the feed restriction. Final BW decreased 41 kg for each percentage unit of diet restriction. Feed efficiency increased 28.72% with feed restriction. For F1 Holstein × Zebu cows in the late lactation, the restriction of dietary supply up to 2.0% of body weight decreases nutrient intake, nitrogen balance, rumination time, and milk production; however, it improves nutrient digestibility and feed efficiency of the animals.

Objetivou-se por meio deste estudo avaliar as características estruturais, produtivas e o valor nutritivo do capim-Tifton 85 adubado com duas doses de nitrogênio em quatro idades de rebrota. Foi utilizado delineamento em blocos casualizados seguindo esquema fatorial 4 x 2, com 4 idades de rebrota (28, 35, 42 e 49 dias) e duas doses de nitrogênio (100 e 300 kg ha-1) com seis repetições, totalizando 48 unidades experimentais de 25 m² (5x5m) cada. O critério de blocagem foi à variação na área experimental. A produção de matéria seca incrementou linearmente, em média 56.4%, à medida que avançou a idade de rebrota de 28 para 49 dias (P<0,01). Entre as doses de N, houve aumento de 17.2% na produção de matéria seca quando adubado com 300 kg ha-1 de nitrogênio. A altura das plantas (P<0,01), assim como o número de folhas vivas (P<0,01), número de folhas expandidas (P<0,01) e o comprimento final da folha (P<0,01) aumentaram linearmente com o avanço da idade corte. A adubação do capim Tifton 85 com 100 kg ha-1 de N, manejado a cada 35 dias melhora a produção de matéria seca, características estruturais e valor nutricional da forragem para corte e/ou pastejo.

The objective of this study was to evaluate the structural, productive and nutritional value of Tifton 85 grass fertilized with two nitrogen doses at four regrowth ages. The experimental design was a randomized block in a factorial 4 x 2, with four regrowth ages (28, 35, 42 and 49 days) and two levels of nitrogen (100 and 300 kg ha-1) in six replicates, totaling 48 experimental units, of 25 m² (5x5m) each. The blocking criterion was the variation in the experimental area. Dry matter production increased linearly, on average 56.4%, as the regrowth age increased from 28 to 49 days (P<0.01). Among the N rates, there was a 17.2% increase in dry matter yield when fertilized with 300 kg / ha of nitrogen. The height of the plants (P <0.01), as well as the number of live leaves (P <0.01), number of expanded leaves (P <0.01) and the final leaf length (P <0.01) increased linearly with the advancement of cut age. Fertilization of Tifton 85 grass with 100 kg ha-1 of N, managed every 35 days improves the dry matter production, structural characteristics and nutritional value of forage for cutting and / or grazing.

RESUMO. Objetivou-se com este trabalho avaliar as características agronômicas e o valor nutricional das silagens de genótipos de milheto. O plantio foi realizado em blocos casualizados, com cinco repetições por genótipo. A produção de matéria verde para os genótipos ADR 500 e CMS 01 foram superiores e semelhantes entre si, com 40,16 e 41,36 t ha (p > 0,05). Não houve diferença significativa para a produção de matéria seca, e a média foi de 9,93 t ha (p > 0,05). As silagens mostraram-se semelhantes (p > 0,05) em relação ao pH, Aw e N-NH3/NT, apresentando valores de 3,92; 0,97 e 7,64%, respectivamente. Não foram encontradas diferenças significativas (p > 0,05) em relação à composição bromatológica das silagens dos diferentes genótipos, sendo observados médios de 30,74% de matéria seca; 10,21% para proteína bruta; 58,69% para fibra em detergente neutro e (p > 0,05). A média da digestibilidade da matéria seca foi de 59,90%. Com base no valor nutricional e na digestibilidade das silagens de milheto, os cinco genótipos apresentam-se adequados à produção de silagem com potencial para o norte de Minas Gerais

ABSTRACT. The objective of this study was to assess agronomic characteristics and nutritional values of silages of millet genotypes. Planting was done in randomized blocks, with five replicates per genotype. Green matter yield for genotypes ADR 500 and CMS 01 was higher and similar to each other, with 40.16 and 41.36 t ha (p > 0.05). There was no significant difference for dry matter yield, with the mean being 9.93 t ha (p > 0.05). The silages were similar (p > 0.05) as to pH, Aw and N-NH3/TN, presenting values of 3.92, 0.97 and 7.64%, respectively. There were no significant differences (p > 0.05) concerning the bromatological composition of the silages of the different genotypes, with a mean of 30.74% of dry matter, 10.21% for crude protein and 58.69% for neutral detergent fiber (p > 0.05). The dry matter digestibility mean stood at 59.90%. Based on the nutritional values and digestibility of the millet silages, the five genotypes are suitable for silage production, with potential for the North of Minas Gerais.

RESUMO. Objetivou-se avaliar as características estruturais, produtivas e nutricionais da palma forrageira (Nopalea cochenillifera Salm Dyck. cv. Miúda/Doce) sob cinco doses de nitrogênio e duas orientações de plantio. Utilizou-se um delineamento em blocos casualizados em esquema fatorial de 5 x 2, sendo cinco doses de nitrogênio (0, 150, 300, 450 e 600 kg de N ha-1), e duas orientações de plantio (Norte/Sul e Leste/Oeste), com três repetições. Com exceção das espessuras de cladódio secundário (p = 0,04) e terciário (p = 0,02), as características morfométricas da palma forrageira não foram influenciadas pelas doses de nitrogênio (p > 0,05), sendo a média da altura de 120 cm e área do cladódio primário, secundário e terciário de 160,9; 208,0 e 158,4 cm², respectivamente. A aplicação de adubo nitrogenado, nas condições de sequeiro e doses avaliadas não afetou a produtividade de massa verde (PMV; p = 0,56), de massa seca (PMS; p = 0,74) e o teor de matéria seca (MS; p = 0,72), sendo as médias de 276,0 t ha-1, 43,2 t ha-1 e 15,7%, respectivamente. O incremento das doses de nitrogênio não melhora a maioria das características morfométricas e nem a PMS da palma forrageira Miúda aos 730 dias após o plantio.

ABSTRACT. This study aimed to evaluate the structural, productive and nutritional characteristics of cactus pear (Nopalea cochenillifera Salm Dyck. cv. Miúda/Doce) under five nitrogen doses and two planting orientations. A randomized block design in a 5 x 2 factorial scheme was used in the scheme: five nitrogen doses (0, 150, 300, 450 and 600 kg of N ha-1), and two planting orientations (North/South and East/West), with three replicates. Except for the thickness of the secondary (p = 0.04) and tertiary cladodes (p = 0.02), the morphometric characteristics of the cactus pear were not influenced by the nitrogen doses (p > 0.05). The mean height was 120 cm, the areas of the primary, secondary and tertiary cladodium were 160.9; 208 and 158.4 cm², respectively. The application of nitrogen fertilizer, in the dry conditions and doses evaluated, did not affect the production of green matter (PGM, p = 0.56), dry matter (PDM, p = 0.74) and dry matter content (DM, p = 0.72), with averages of 276 t ha-1, 43.2 t ha-1 and 15.7%, respectively. The increase of the nitrogen doses does not improve the majority of the morphometric characteristics or the dry matter yield of the cactus pear cv. Miúda at 730 days after planting.

Objetivou-se avaliar o efeito e o melhor nível de inclusão de glicerina bruta na ensilagem de capim Tifton 85 (Cynodon dactylon) sobre os parâmetros fermentativos e a composição química da silagem. Os tratamentos consistiram de silagem de capim Tifton 85 (controle) e silagem de capim Tifton 85 com quatro níveis de inclusão de glicerina bruta (1, 5, 10 e 15% de inclusão na matéria natural) durante a ensilagem. Utilizou-se um delineamento inteiramente casualizado sendo quatro tratamentos mais o controle com cinco repetições. Foi verificado que a inclusão de 1%, 5%, 10% e 15% de glicerina bruta diminuiu 18%, 18%, 20% e 22% o valor de pH em relação a silagem controle (5,0), respectivamente. A inclusão de 15% de glicerina bruta na silagem de capim Tifton 85 aumentou 4,3% o teor de carboidratos totais, 67,4% o teor de extrato etéreo e 17,7% o teor de nutrientes digestíveis totais em relação à silagem controle. A utilização de 15% de glicerina bruta na matéria natural de capim Tifton 85 durante a ensilagem melhora o perfil fermentativo e as características nutricionais da silagem.

This study aimed to evaluate the effect and the best level of crude glycerin inclusion in grass ensiling Tifton 85 (Cynodon dactylon) on fermentative parameters and silage chemical composition. Treatments consisted of Tifton 85 grass silage (control) and silage Tifton 85 grass with four levels of inclusion of crude glycerin (1, 5, 10 and 15% inclusion in natural matter) during ensiling. A completely randomized design with four treatments more control with five replications was used. It has been found that the inclusion of 1%, 5%, 10%, 15% crude glycerin decreased by 18%, 18%, 20% and 22%, the pH value compared to the control silage (5.0), respectively. The inclusion of 15% crude glycerin in silage Tifton 85 grass increased by 4.3% in total carbohydrate, 67.4% in the ether extract and 17.7% in the total digestible nutrient content compared to control silage. The use of 15% crude glycerin in the natural field of Tifton 85 grass during ensiling enhances the fermentation profile and the nutritional characteristics of silage.

RESUMO. Objetivou-se com este estudo avaliar as perdas fermentativas e o valor nutricional das silagens de capim-elefante com níveis crescentes de inclusão da casca de banana desidratada. O experimento foi conduzido em delineamento inteiramente casualizado, com seis tratamentos e quatro repetições, sendo silagem exclusiva de capim-elefante e cinco níveis de inclusão da casca de banana à silagem de capim-elefante - 5; 10; 15; 20 e 25%, sendo adicionada com base na matéria natural. A adição da casca de banana na ensilagem reduziu linearmente (p < 0,05) o pH, nitrogênio amoniacal e as perdas do processo fermentativo. Ademais, a inclusão da casca de banana aumentou de forma linear (p < 0,05) a matéria seca e os carboidratos não fibrosos. Já a fibra em detergente neutro e em detergente ácido reduziu linearmente com inclusão da casca de banana (p < 0,05), mas não houve alteração na digestibilidade in situ da matéria seca. A inclusão de casca de banana desidratada na ensilagem do capim-elefante reduz as perdas do processo fermentativo com resultados mais consistentes no nível de 25% de inclusão, entretanto, reduz o valor nutricional por detrimento da qualidade fibrosa e proteica.

ABSTRACT. The aim of this study was to evaluate the fermentative losses and nutritional value of elephant grass silages with the increasing of inclusion levels of dehydrated banana peel. The experiment was conducted in a completely randomized design, with six treatments and four replications, being the silage exclusively from elephant grass, and five levels of inclusion of banana peel to the elephant grass silage, as the following - 5; 10; 15; 20 and 25%, being added based on natural matter. The addition of the banana peel in the silage reduced linearly (p < 0.05) the pH, the ammoniacal nitrogen and the losses of the fermentative process. In addition, the inclusion of banana peel increased linearly (p < 0.05) the dry matter and non-fibrous carbohydrates. On the other hand, the neutral detergent fiber and the acid detergent fiber were linearly reduced with the inclusion of the banana peel (p < 0.05), but there was no change in the dry matter digestibility in situ. The inclusion of dehydrated banana peel in elephant grass silage reduces the losses of the fermentation process with more consistent results at the 25% inclusion level, however, it reduces the silage nutritional value due to fibrous and protein quality.

RESUMO. Objetivou-se avaliar as características nutricionais e qualidade das silagens de cinco genótipos de sorgo, sendo eles: Volumax, AG2005E, Qualimax, BRS610 e AG2501. O estudo foi conduzido na fazenda experimental da Unimontes, situada no município de Janaúba-MG.Os tratamentos foram distribuídos em blocos ao acaso com quatro repetições. Os dados foram submetidos às análises de variância e para a comparação das médias foi utilizado o teste de Scott-Knott ao nível de significância de 5% de probabilidade. Os valores de pH variaram entre 3,93 e 4,10. Os genótipos diferiram entre si em todas as características nutricionais avaliadas (p < 0,05). Para a fibra em detergente ácido foi encontrado diferença entre os genótipos avaliados, AG2501 (35,66%), Volumax (34,89%), AG2005E (34,53%), Qualimax (32,39%) e BRS610 (33,60%). A alta participação da lignina foi verificada para todos os genótipos, exceto o Volumax (4,14%). Todas as silagens encontraram-se dentro da faixa recomendada de 50 a 65% para digestibilidade in vitro da matéria seca, sendo classificadas como de boa qualidade, no entanto somente o genótipo AG2005E atendeu aos requisitos de nitrogênio para uma fermentação microbiana, com 7,06% de proteína bruta.

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.

RESUMO. Objetivou-se determinar e mensurar os ácidos fenólicos em quatro variedades de cana-de-açúcar (RB 855536, RB 765418, SP 80-1842 e SP 80-1816) na forma in natura e ensilada, bem como avaliar a influência destes ácidos sobre a degradabilidade in situ da matéria seca e fibra em detergente neutro. O delineamento experimental foi inteiramente casualizado em esquema fatorial. Para a fração da matéria seca (MS), as variedades RB 855536 e SP 80-1842 tiveram médias 17,80% superior em relação às demais. As variedades SP 80-1842 e RB 855536, não diferiram entre si (p > 0,05) com média de degradabilidade efetiva da MS de 33,70%. Para a silagem, os maiores teores de ácido p-cumárico foram constatados na variedade RB 855536 que foi 24,64% superior às variedades RB 765418 e SP 80-1842 (média de 12,75%) e 52,60% à variedade SP 80-1816 (média de 8,02%), sendo que para a forma in natura, as variedades não diferiram entre si (p > 0,05), média de 8,86%. A silagem da variedade SP 80-1816 apresentou teor de ácido ferúlico 40,82% superior às demais variedades, média 4,63%. A verificação das concentrações dos ácidos fenólicos p-cumárico e ferúlico não são suficientes para justificar o efeito da ação microbiana sobre as variedades estudadas nas diferentes formas de processamento.

ABSTRACT. This study aimed to determine and measure the phenolic acids in four varieties of sugarcane (RB 855536, RB 765418, SP 80-1842 and SP 80-1816) as fresh and ensiled, and assess the influence of these acids on in situ degradability of dry matter and neutral detergent fiber. The experimental design was completely randomized in a factorial design. For the fraction of dry matter (DM), varieties RB 855536 and SP 80-1842 had average 17.80% higher compared to others. The SP80-1842 and RB 855536 varieties did not differ (p > 0.05), with an average of DM effective degradability of 33.70%. For silage, the highest levels of p-coumaric acid were found in the variety RB 855536, which was 24.64% higher than the varieties RB 765418 and SP 80-1842 (average 12.75%) and 52.60% of the variety SP 80-1816 (average 8.02%), since for the in natura form, varieties did not differ between each other (p > 0.05), and had an average of 8.86%. Silage variety SP 80-1816 has ferulic acid content 40.82% higher than the other varieties, with an average of 4.63%. The examination of the concentrations of phenolic acids p-coumaric and ferulic are not sufficient to justify the effect of microbial action on the varieties studied in different forms of processing.

RESUMO Objetivou-se avaliar a cinética da fermentação e taxas de degradação de gramíneas do gênero Cynodon estimadas pela técnica semi automática de produção de gases in vitro. As forrageiras utilizadas foram: Coastcross, Tifton 85 e Tifton 68. As leituras de pressão foram realizadas nos tempos: 0, 2, 4, 6, 8, 10, 12, 15, 19, 24, 30, 36, 48, 72 e 96h. A degradabilidade da matéria seca (DMS) foi obtida pela porcentagem de matéria seca (MS) remanescente após 0, 6, 12, 24, 48 e 96h de fermentação. A gramínea Tifton 85 apresentou uma produção total de gases superior (p <0,05). Maiores taxas de fermentação ocorreram no tempo inicial de fermentação decrescendo (p <0,05) com o avançar do tempo. As gramíneas Tifton 85 e Tifton 68 apresentaram valores superiores (p <0,05) de fração solúvel, insolúvel potencialmente degradável, insolúvel, degradabilidade potencial e efetiva da matéria seca em relação à gramínea Coastcross. Maior produção de gases durante a incubação in vitro da matéria seca foi observada para o capim Tifton 85.

ABSTRACT The present study aimed to evaluate the fermentation kinetics and degradation rates of Cynodon grasses estimated by semi-automated technique of in vitro gas production. The forages were: Coastcross, Tifton 85 and Tifton 68. Pressure readings were taken at 0, 2, 4, 6, 8, 10, 12, 15, 19, 24, 30, 36, 48, 72 and 96 hours. Dry matter degradability (DMD) was obtained by the percentage of dry matter (DM) remaining after 0, 6, 12, 24, 48 and 96 hours of fermentation. Tifton 85 showed a higher total gas production (p <0.05). Higher fermentation rates were found at the beginning of fermentation followed by subsequent reduction (p <0.05) over time. Tifton 85 and Tifton 68 showed higher values (p < 0.05) for soluble fraction, potentially degradable insoluble fraction, insoluble fraction, potential and effective degradability of dry matter in relation to Coastcross grass. Higher gas production during in vitro incubation of dry matter was observed for Tifton 85 g.

RESUMO Objetivou-se avaliar as características agronômicas de genótipos de sorgo e o valor nutricional das silagens produzidas. Foram utilizados 15 genótipos de sorgo. O plantio foi realizado em blocos casualizados com três repetições por genótipo num total de 45 (quarenta e cinco) parcelas. Avaliaram-se as características agronômicas, nutricionais e qualidade da silagem. Houve diferença entre os genótipos para todas as características analisadas, com exceção dos teores de nitrogênio indisponível em detergente ácido (NIDA), proteína indisponível em detergente ácido (PIDA) e atividade de água (aw). Avaliando os parâmetros, com exceção dos genótipos 1016013, 1016025, 1016037, 1016039, Volumax, BRS 610, que apresentaram teor proteico abaixo de 7 %, os demais estão aptos a serem utilizados para a ensilagem, pois possuem um bom perfil de fermentação e digestibilidade in vitro da matéria seca; no entanto, o genótipo SF 15 é o mais favorável para a produção de silagem, devido à sua menor participação na fração de fibra em detergente neutro.

ABSTRACT 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.

RESUMO Objetivou-se avaliar consumo, digestibilidade, comportamento ingestivo e produção de leite de vacas F1 Holandês x Zebu alimentadas com dietas contendo casca de banana seca ao sol com ou sem adição de agentes químicos durante o processo de secagem. Utilizou-se dois quadrados latinos 4 x 4, compostos por quatro dietas, quatro animais e quatro períodos experimentais. As dietas foram formuladas para ser isoprotéicas, com relação volumoso:concentrado de 75:25. Os tratamentos consistiram de 20% de inclusão da casca de banana seca com ou sem adição de 2% de calcário ou 2% de óxido de cálcio, em substituição à silagem de sorgo, além da dieta sem casca de banana. Foram utilizadas oito vacas com 80 ± 10 dias de lactação ao início do experimento, que teve duração de 72 dias, divididos em quatro períodos de 18 dias, com 14 dias de adaptação e quatro dias de coleta de amostras e dados. A casca de banana com óxido de cálcio reduziu os tempos de ruminação e mastigação total e o número de bolos ruminados por dia. Todavia, não alterou as eficiências de alimentação e ruminação da MS e FDN. A utilização da casca de banana seca ao sol em 20% da dieta não altera produção de leite, com produção média de 16,88 kg de leite com 3,5% de gordura.dia-1. Entretanto, reduz a digestibilidade da MS e dos nutrientes, podendo limitar o ganho de peso dos animais. A utilização de aditivos na secagem da casca de banana não melhora o consumo e produção de leite.

SUMMARY The study purpose was to evaluate the intake, digestibility, ingestive behavior and milk production of F1 Holstein x Zebu cows fed with diets containing dried banana peel in the sun with or without addition of chemical agents during the drying process. We used two Latin squares 4 x 4, composed of four diets, four animals and four experimental periods. The diets were formulated to be isonitrogenious with forage to concentrate ratio of 75: 25. Treatments consisted of 20% inclusion of dried banana peel with or without addition of 2% of limestone or 2% of calcium oxide, replacing the sorghum silage, apart from free banana peel diet. Were used eight cows with 80 ± 10 days in milk at the beginning of the experiment, which lasted 72 days, divided into four periods of 18 days with 14 days for diet adaptation and four days of sampling and data collection. The banana peel with calcium oxide decreases rumination time, the total chewing time and the number amounts ruminated per day. However, it didn’t change the feed and rumination efficiencies of DM and NDF. The utilization of dried banana peel in the sun in 20% of the diet doesn’t alter milk yield, with average production of 16.88 kg of milk with 3.5% of fat.day-1. However, reduces DM and nutrients digestibility, which may limit the weight gain of the animals. The use of additives in banana skin drying does not improve the consumption and production of milk.