A.L.C.C. Borges

Concentrados protéicos para bovinos: 1. Digestibilidade in situ da matéria seca e da proteína bruta

This work aimed to determine the in situ rumen digestibility of dry matter (DM) and crude protein (CP) using 10 protein sources. Potential degradabilities of DM and CP of soybean meal, cottonseed meal, castorbean meal and palmist coconut meal were high (around 100%), however due to higher fractional degradation rates of soybean meal (10%) and lower for cottonseed meal (4%), castorbean meal (DM:3%, CP:1.2%) and palmist meal (1.7%), the effective degradability (ED) of soybean was significantly higher despite the rates of passage, showing this protein source has the highest ruminal nitrogen availability (from 86% to 63%, as rate of passage increased from 2 to 8%). Gluten meal is a low rumen degradable protein source (ED of CP: 16% for 0.05 passage rate). Among protein sources of animal origin, the highest potential CP degradability was observed for meat and bone meal (75.5%), followed by fish meal I (58.5%), feather and viscera meal (52.3%), and blood meal (36.7%). The highest ED for a passage rate of 5% was observed for meat and bone meal (51%), followed by fish meal I (41%), feather and viscera meal (40%) and blood meal (33%). Fish meal II showed very low rumen degradability with only 22% of CP disappearance at 48 hours of incubation.

Qualidade das silagens de três híbridos de sorgo ensilados em cinco diferentes estádios de maturação

Three hybrids of sorghum with medium height (BR700, BR701 e MASSA 03) for silage production were evaluated. Hybrids were harvest at five different maturation stages. Dry matter content, pH, ammonia nitrogen, crude protein, fibrous fractions, in vitro dry matter digestibility and organic acids were determined in silage. A completely randomized block design with three replicates was used. The treatments consisted in a factorial arrangement 5x3 (maturation stages x hybrids). The means were compared by SNK test (P<0.05). Dry matter content and pH values increased with the maturation stage; pH values were always lower than 4.09. No effects of maturation stage of the plant on ammonia nitrogen, fibrous fractions and in vitro dry matter digestibility were found. Organic acids contents suggested that the fermentation inside the silo was enough for preservation of the forage.

A calorimetry system for metabolism trials

An indirect calorimetry system for rapid determination of CO2 and CH4 production and O2 consumption to estimate heat production of animals was built at Escola de Veterinaria da Universidade Federal de Minas Gerais, Brazil. Procedures for determination of correction and calibration factors for gas analyzers and the whole system, using standard test gases were described. In addition, a metabolic trial was performed to evaluate heat production of lambs fed ad libitum. It is concluded that the system is suitable for heat production determinations in small and medium size animals.

Silagem de sorgo de porte baixo com diferentes teores de tanino e de umidade no colmo. III- Quebra de compostos nitrogenados

Four hybrid forage sorghums with different tannin concentrations and moisture in the stem were ensiled in laboratory silos made of PVC tubes. The silos were opened 1 (P2), 7 (P3), 14 (P4), 28 (P5) e 56 (P6) days after ensiling, in order to evaluate fermentation patterns and others parameters. Twenty-four treatments were used, with four repetitions each: 4 hybrids (T1=moist stem/low tannin, T2=not moist stem/low tannin, T3=not moist stem/high tannin, T4= moist stem/high tannin) and with six periods, since the forages before ensiling were also studied. Dry matter content (DM), crude protein (CP), ammonia nitrogen (N-NH3) and tannin were determined. Data were evaluated by analysis of variance, with mean separation achieved using Tukey statistical test. All sorghums had N-NH3 production during the fermentation, which was lower in high tannin sorghums. The N-NH3 concentrations were lower than those in the literature. High tannin sorghums had higher dry matter contents.

Degradabilidade in situ da cana-de-açúcar tratada ou não com óxido de cálcio, em novilhas leiteiras Holandês x Gir

In situ degradability of sugarcane in natura or added to different levels of calcium oxide (CaO) in fed diet, 0.0; 0.5; 1.0 and 2.0% for 24 h in five Holstein x Gyr heifers, fitted with a rumen cannula.The parameters of rumen degradation of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were estimated by adjusting non-linear model to data degradation, and used the parameters obtained in regression analysis, linear and quadratic performed according to the level of inclusion of calcium oxide in diets.The potential and effective degradability, as well as the degradation rates of DM and OM were lineraly enhanced with the increasing of the CaO levels in diet. The increasing levels of CaO in sugarcane diets offered to Holstein x Gyr dairy heifers lead to a linear enhancement of in situ degradability of DM and OM, but does not affect the in situ degradability of fiber fractions.

Uso do óxido crômico e do LIPE® na estimativa do consumo de matéria seca por bezerros de corte

Six male and six female calves, seven-month-old, averaging 168kg bw, grazing on Brachiaria decumbens, were used in a split plot design to compare the efficacy of two external markers: chromic oxide (Cr2O3) and purified and enriched lignin (LIPE®) simultaneously dosed once a day to predict dry matter intake (DMI). For both, Cr2O3 and LIPE®, no differences in DMI according to gender were observed. Comparing the efficacy of the two markers to predict fecal output and pasture intake, the estimates obtained with chromic oxide were lower. Forage DMI, total DMI, DMI as percentage of body weight, and DMI in relation to metabolic weight were: 2.03 and 4.50kg; 2.71 and 5.18kg; 1.62 and 3.10%, and 58.10 and 111.32g/kg bw0.75 for Cr2O3 and LIPE®, respectively. These results suggest that estimates obtained from LIPE® were more appropriate to the dry matter requirements and performance of the calves.

Padrão de fermentação da silagem de cinco genótipos de sorgo

Foram utilizados cinco genotipos de sorgo de colmo seco, sendo dois hibridos comerciais (Volumax e BR 700) e tres novos hibridos experimentais desenvolvidos pela Embrapa Milho e Sorgo (0249341, 0249317 e 0249339), com o objetivo de determinar, no material original e em sete tempos de abertura subsequentes a ensilagem (1, 3, 5, 7, 14, 28 e 56), as porcentagens de materia seca, proteina bruta, nitrogenio amoniacal em relacao ao nitrogenio total, pH e carboidratos soluveis em alcool. Os valores de materia seca dos materiais originais foram semelhantes aos das silagens em todos os dias de abertura. Os valores de materia seca das silagens variaram entre 26,03 e 41,13% com media 32,65%. Os valores de proteina bruta foram menores no 56° dia de abertura comparados aos dos materiais originais. A degradacao dos carboidratos soluveis foi intensa ate o quinto dia de fermentacao. Os valores de nitrogenio amoniacal foram baixos e estaveis ate o 28° dia pos-ensilagem, com pequeno aumento no 56° dia e a variacao neste ultimo periodo foi de 2,01 a 3,66%. Os valores de pH variaram de 3,69 a 4,52 e sua estabilizacao se deu no quinto dia pos-ensilagem. De maneira geral, os hibridos avaliados apresentaram potencial para serem utilizados na forma de silagem.

Consumo e digestibilidade aparente da matéria seca, da proteína bruta e da energia de silagens de quatro genótipos de sorgo (Sorghum bicolor (L.) Moench) por ovinos

The nitrogen balance, the consumption and the apparent digestibility of dry matter, crude protein and the energy of the silages of four genotypes of sorghum were evaluated. The consumption of dry matter and crude energy did not differ among the hibrids. The largest apparent digestibility of dry matter, crude energy and the consumption of digestible dry matter and energy, were observed for BR601 genotype. The largest consumption of crude protein, was observed for BR700 and the smalest for AG2002 genotypes (P<0.05). The largest apparent digestibility of protein was observed for BR601 and the smalest one for BR701 (P<0.05) genotype. The consumption of digestible protein was larger for BR601 and BR700. All treatments showed positive nitrogen balance and did not differ among them.

Consumo e digestibilidade aparente das frações fibrosas de silagens de quatro genótipos de sorgo (Sorghum bicolor (L.) Moench) por ovinos

Intake and digestibility of silage fibrous fractions of four genotypes of sorghum were evaluated in sheep. The higher intake of NDF was observed for hybrid silages BR701 and BR601 (P<0.05), and hybrid BR700 did not differ from the others. BR601 showed the highest digestibility of NDF and BR700 the lowest (P<0.05). The highest intake of digestible NDF was observed in BR601 (P<0.05) and BR700 and AG2002 showed the lowest. BR700 had the highest ADF intake and AG2002 the lowest (P<0.05). Digestibility of ADF was superior in hybrids BR601 and BR700 when compared to AG2002 (P<0.05). The highest intake of digestible ADF was observed in BR700 and the lowest in AG2002. Cellulose intake was the highest in BR700 and the lowest in AG2002(P<0.05). No differences on digestibilities of cellulose among the hybrids were found, but the intakes of digestible cellulose were superior in BR700, BR701 and BR601 (P<0.05). The animals fed on BR601 showed the highest consumption of hemicellulose but there were no differences among digestibilities of hemicellulose intakes. The highest intake of lignin was observed for animals fed on hybrid BR700 sorghum silage and the lowest for those fed on BR601 and AG2002 silages (P<0.05).

Evaluation of the infrared spectroscopy method for the quantification of NANOLIPE marker in feces of dairy cattle

LIPE® is an external marker obtained from lignin isolated from Eucaliptus grandis and enriched with phenolic groups that is used to estimate dry matter intake and digestibility (Saliba et al., 2003). Recently, methodological improvements in obtaining LIPE® led to the production of a newer and better version of this marker. Its particles have now reached the nano scale and for this reason it was called NANOLIPE (Saliba et al., 2012). The Fourier Transform Infrared Spectroscopy (FT-IR) is used for the quantification of NANOLIPE in feces. However, one of the key points to ensure the quality of the results is to assess the linearity of the calibration curves used in the determinations (Thompson, 2005). Therefore, the aim of this study was to statistically evaluate the linearity of the FT-IR method in quantifying NANOLIPE in feces of dairy cattle.