RESUMO
Rumen-protected fat (RPF) was produced in the 1st experimental stage through melt-emulsification technique using buriti oil (BO) as core, at concentrations of 10% (BO10), 20% (BO20), and 30% (BO30) (w/w), and carnauba wax (CW) as encapsulant material. After obtention and characterization, protected fat microspheres were tested in a 2nd experimental stage on the sheep' diet using six castrated 2-year-old male Santa Ines with initial weight 48.9 ± 5.23 kg, fistulated in rumen and distributed in a double Latin square design with 3 treatments × 3 periods, to evaluate rumen pH, temperature, protozoal count, and blood parameters. There was no difference (P > 0.05) among RPF microspheres for microencapsulation yield. However, microencapsulation efficiency increased (P < 0.05) with BO addition ranging from 36 to 61.3% for BO10 and BO30, respectively. The inclusion of BO10 in the sheep's diet did not affect the ruminal dry matter degradability (DMD) of BO over time (P > 0.05); however, BO20 and BO30 had higher (P < 0.05) DMD values than BO10. No significant differences were observed among RPF for rumen pH and temperature (P > 0.05). There was an increase (P < 0.05) in the protozoal population in the rumen environment due to the microencapsulated BO30 inclusion. There was also increase (P < 0.05) in serum albumin, cholesterol, aspartate aminotransferase (ALT), and gamma-glutamyltransferase (GGT), and a reduction (P < 0.05) in serum triglycerides of the sheep when RPF microspheres increased in the diet. Melt-emulsification proved to be a good technique for microencapsulation of buriti oil into the carnauba wax matrix. RPF from buriti oil protected into carnauba wax is recommended for sheep diet because it increases energy density, without adverse effects on the protozoal populations and blood serum metabolites from the bypass effect in the rumen.
Assuntos
Dieta , Rúmen , Animais , Masculino , Ração Animal/análise , Dieta/veterinária , Suplementos Nutricionais , Digestão , Fermentação , Rúmen/metabolismo , OvinosRESUMO
The effects of the replacement of dry ground corn (GC) with corn-grain silage rehydrated with water (RCSwater), cactus pear mucilage (RCSmucilage), and whey (RCSwhey) on the growth, physicochemical composition, and fatty acid profile of goat kids' meat were investigated. Thirty-two crossbred goat kids (16.4 ± 2.50 kg initial weight) were assigned in a randomized block design with four treatments and eight repetitions. The NDF intake of goat kids fed with RCSmucilage was higher in comparison to RCSwater and RCSwhey (p = 0.0009). The dietary replacement of GC by RCSmucilage increased the final weight (p = 0.033) and meat-cooking losses (p = 0.0001) of kids. The concentrations of oleic (p = 0.046), 11,14-eicosadienoic (p = 0.033), and EPA (p = 0.010) were higher in the meat of kids fed with RCSmucilage and RCSwhey, and the α-linolenic concentration was higher (p = 0.019) for animals feeding with RCSmucilage. Meat from kids fed with RCSwhey presented the lowest ∑SFA and the highest ∑MUFA. In contrast, the ∑PUFA (p < 0.012) was higher for goats fed with RCSwater. The ∑ω3 (p < 0.0001) was higher in animals fed with RCSmucilage and RCSwhey. Desirable fatty acids were higher (p = 0.044) in animals fed with RCSmucilage and RCSwhey, and the atherogenicity (p = 0.044) and thrombogenicity (p < 0.0001) indexes were lower for goats fed the RCSwhey diet. The enzymatic activities of Δ9desaturase (C16) were higher (p = 0.027) in goat kids fed with GC and RCSmucilage, and Δ9desaturase (C18) was higher (p = 0.0497) when goats were fed with RCSmucilage and RCSwhey. Elongase activities were higher (p = 0.045) in goat kids fed with GC and RCSwater. The total replacement of GC by RCSmucilage is recommended in the diet of goat kids due to improvements in the weight gain and proportion of desirable fatty acids in the meat. In addition, RCSmucilage promoted better conservation of the silage at a lower cost when compared to commercial additives.