André Oliveira Casali

Influence of incubation time and particles size on indigestible compounds contents in cattle feeds and feces obtained by in situ procedures

The aim of this work was to evaluate the effects of in situ incubation time and particles size on the estimates of indigestible fractions of dry matter (iDM), neutral detergent fiber (iNDF), and acid detergent fiber (iADF) in cattle feeds and feces. Samples of corn grain, wheat bran, corn silage, elephant grass, sugarcane, signal grass hay, corn straw, and feces obtained from cattle fed high and low concentrate diets were used. The samples were ground through 1 mm, 2 mm, and 3 mm screen sieve and put in 4 × 5 cm non-woven textile bags (20 mg DM/cm² of surface). The samples were divided in three groups, being each group incubated in the rumen of a crossbred heifer. The incubation procedure was conducted three times with the change of groups among animals. The following incubation times were used: 0, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216, 240, and 312 hours. The contents of iDM, iNDF, and iADF were evaluated sequentially in each bag. The degradation profiles were interpreted by a non-linear logistic model. The particles size did not influence the estimates of iNDF and iADF. However, the particles size altered the rumen degradation dynamic rates of DM for corn silage and corn grain; of NDF for sugarcane, corn silage, and corn straw; and ADF for sugarcane. For those samples, the particle size has been positively associated with the incubation time necessary to estimate the indigestible fraction. Incubation times of 240 hours for DM and NDF, and 264 hours for ADF were suggested for obtaining more accurate estimates of indigestible fractions. The use of 2 mm particle size can increase the precision of estimates.

Estimation of fibrous compounds contents in ruminant feeds with bags made from different textiles

The aim of this work was to evaluate the contents of in situ indigestible neutral detergent fiber (iNDF) and the fibrous particles lost in aqueous environment in some ruminant feeds by using bags made with different textiles. The physical structure of the textiles was also observed. Wheat bran (WB), soybean hulls (SH), corn silage (CS), and signal grass hay (SGH) samples were used. The bags used for rumen incubation were made of nylon (50 µm); F57 (Ankom®); and non-woven textile (NWT -100 g/m²). The feed samples were ground (1 mm) and conditioned in bags (4 × 5 cm) (six bags of each feedstuff/textile), in a ratio of 20 mg of dry matter/cm2 of surface. The bags were incubated in the rumen of a cow fed with corn silage (70%) and concentrate (30%) for 144 hours. After that, the bags were removed, cleaned with running water and treated with neutral detergent. The residue was assumed as iNDF. The iNDF contents in WB, SH and CS were similar for F57 and NWT, but lower values were obtained when nylon was used For the SGH samples, all textiles produced different results, and the lowest contents were obtained with nylon. The fibrous particle losses in the aqueous environment were evaluated by cleaning the bags in warm running water (39oC) (10 bags/textile). The loss of fibrous particles was significant for nylon. This loss was considered the cause of lower iNDF contents obtained by using nylon textile, since the microscopic evaluation did not show the occurrence of ruptures during incubation or neutral detergent extraction.

Produção e qualidade da forragem de capim-marandu fertiirrigada com dejetos líquidos de suínos

Esta pesquisa foi realizada com o objetivo de avaliar os efeitos da fertilizacao com dejetos liquidos de suinos (DLS) nas caracteristicas agronomicas e bromatologicas da forragem de capim-marandu. Foram avaliados a produtividade de MS, o perfilhamento, o percentual de MS, PB, FDN e FDA e a digestibilidade in vitro da MS (DIVMS). Adotou-se o delineamento em blocos casualizados, com nove tratamentos (adubacoes) e quatro repeticoes. Os tratamentos sao descritos a seguir: T1 - uso de calcario; T2 - adubacao com 100, 40 e 60 kg/ha de N P K; T3 - 180 m3 de DLS/ha 1x/ano; T4 - 180 m3 de DLS/ha 2x/ano); T5 - 180 m3 de DLS/ha 3x/ano; T6 - 180 m3 de DLS/ha 4x/ano; T7 - 180 m3 de DLS/ha 5x/ano; T8 - 180 m3 de DLS/ha 1x/ano (in natura); T9 (testemunha) - fermentacao do DLS utilizado nos tratamentos 1, 2, 8 e 9 por, no minimo, 45 dias. As medias foram comparadas pelo teste Scott-Knott. Na calagem, utilizou-se alcario dolomitico na proporcao de 3 t/ha e, na adubacao quimica, 100, 40 e 60 kg/ha de N, P2O5 e K2O nas formas de sulfato de amonia supersimples e cloreto de potassio. Os cortes foram realizados a cada 45 dias. O numero de perfilhos/m2, a produtividade de MS e a qualidade da forrageira foram maiores com a utilizacao de DLS em dose unica nos primeiros cortes. As forrageiras dos tratamentos 3, 4, 8 e 9 apresentaram maiores teores de PB nos primeiros cortes, com medias de 9,6 a 13,7%. Os maiores teores de FDN foram obtidos no segundo corte (medias de 61,4 a 68,6%) e os menores de FDA foram encontrados com DLS 2x/ano e 5x/ano no primeiro corte (medias de 21,2 a 23,4%). Os tratamentos 3, 4 e 8 proporcionaram os maiores coeficientes de DIVMS no primeiro corte, com medias de 69,0 a 71,8%.

Uso de diferentes aditivos em silagem de capim-elefante

Objetivou-se avaliar o uso de diferentes aditivos na ensilagem de Capim-Elefante. O delineamento experimental foi o inteiramente casualizado. Os tratamentos foram: T1(capim-elefante), T2 (capim-Elefante + 7% polpa citrica), T3 (capim-elefante + 7% raspa de batata), T4 (capim-elefante + 7% milho desintegrado com palha e sabugo MDPS), T5 (capim-elefante + 7% farelo de trigo), T6 (capim-elefante + aditivo biologico). Os tratamentos com aditivos secos (T1; T3; T4 e T5) apresentaram maiores valores de materia seca diferindo estatisticamente (p 0,05) entre os tratamentos, variando de 3,87 (T1) a 4,04 (T3). Houve diferenca significativa (p<0,05) para perda de gases, sendo maior nos tratamentos T2 e T5. Os demais tratamentos nao diferenciaram estatisticamente entre si. A perda por efluentes foi maior no tratamento T6 (57,30 kg/Ton. de MV). Para Proteina Bruta o tratamento T5 apresentou maior porcentagens e o tratamento T1 foi o de menor teor. Os tratamentos T1 (69,79% FDN) e T6 (70,52% FDN) apresentaram maiores valores de FDN. Os tratamentos T4 e T3 obtiveram menores valores de FDN. Quanto aos valores de FDA, os tratamentos T1 e T6 apresentaram maiores valores de FDA e os tratamentos T3 e T4 apresentaram menores valores. Para os valores de DIVMS variaram de 56,04% (T1) a 71, 13% (T3). A silagem de Capim Elefante sem aditivos e/ou com aditivo biologico utilizado neste experimento nao apresentou melhoria em sua qualidade.

Qualidade bromatológica das silagens de cana-de-açúcar (Saccharum officinarum L.) aditivadas com raspa de batata

Potato scrapings were mixed with sugarcane (Sacharum officinarum L.) in the silage. Sugarcane was havested manually after a leveling cut had been done at a height of 10 cm from the soil surface. The mixtures of sugarcane and potato scrapings were made in the following ratios of natural matter: 100% and 0%; 93% and 7%; 86% and 14%; 79% and 21%; and 72% and 28% of sugarcane and potato scrapings, respectively. The plants were chopped into 2-3 cm particles and ensiled for 30 days in 10 cm wide x 40 cm high “PVC” silos. The following variables of the silage were evaluated: percentage of dry matter (DM), pH values, gas lossses, effluent losses, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and in vitro digestibility of dry matter (IVDDM). The experimental design used was the completely randomized with four replications. The sugarcane silages added with potato scrapings exhibited higher percentages of DM and CP, higher values of pH, increase in the IVDDM, and a lower percentage of loss of gases, loss of effluent, NDF and ADF in dry matter with increasing levels of replacement. It was concluded that the dry potato scrapings added to the sugarcane in silage improved the chemical and nutritional characteristics of the silages.

Bromatologic quality of sugarcane (Sacharum officinarum L.) silages supplemented with potato scrapings.

Potato scrapings were mixed with sugarcane (Sacharum officinarum L.) in the silage. Sugarcane was havested manually after a leveling cut had been done at a height of 10 cm from the soil surface. The mixtures of sugarcane and potato scrapings were made in the following ratios of natural matter: 100% and 0%; 93% and 7%; 86% and 14%; 79% and 21%; and 72% and 28% of sugarcane and potato scrapings, respectively. The plants were chopped into 2-3 cm particles and ensiled for 30 days in 10 cm wide x 40 cm high “PVC” silos. The following variables of the silage were evaluated: percentage of dry matter (DM), pH values, gas lossses, effluent losses, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and in vitro digestibility of dry matter (IVDDM). The experimental design used was the completely randomized with four replications. The sugarcane silages added with potato scrapings exhibited higher percentages of DM and CP, higher values of pH, increase in the IVDDM, and a lower percentage of loss of gases, loss of effluent, NDF and ADF in dry matter with increasing levels of replacement. It was concluded that the dry potato scrapings added to the sugarcane in silage improved the chemical and nutritional characteristics of the silages.

Bromatologic quality of sugarcane (Sacharum officinarum L.) silages added with potato scrapings

Potato scrapings were mixed with sugarcane (Sacharum officinarum L.) in the silage. Sugarcane was havested manually after a leveling cut had been done at a height of 10 cm from the soil surface. The mixtures of sugarcane and potato scrapings were made in the following ratios of natural matter: 100% and 0%; 93% and 7%; 86% and 14%; 79% and 21%; and 72% and 28% of sugarcane and potato scrapings, respectively. The plants were chopped into 2-3 cm particles and ensiled for 30 days in 10 cm wide x 40 cm high “PVC” silos. The following variables of the silage were evaluated: percentage of dry matter (DM), pH values, gas lossses, effluent losses, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and in vitro digestibility of dry matter (IVDDM). The experimental design used was the completely randomized with four replications. The sugarcane silages added with potato scrapings exhibited higher percentages of DM and CP, higher values of pH, increase in the IVDDM, and a lower percentage of loss of gases, loss of effluent, NDF and ADF in dry matter with increasing levels of replacement. It was concluded that the dry potato scrapings added to the sugarcane in silage improved the chemical and nutritional characteristics of the silages.