Physicochemical Composition and Fatty Acid Profile of Goat Kids’ Meat Fed Ground-Corn-Grain Silage Rehydrated with Different Additives

SIMPLE SUMMARY: Corn is one of the most produced grains in the world, being the primary energy concentrate used in animal feeding due to its nutrition quality and high cultivation potential, which make it the main source of starch in the diets of ruminant animals. We compared three different moisture additives to conserve rehydrated corn-grain silage, namely water, cactus mucilage, and whey, and replaced ground corn (GC) with rehydrated corn-grain silage in the finishing of kids’ diet. Cactus pear cladode mucilage was a more efficient moisture additive than water and whey for ground-corn silage. Thus, it is recommended to replace ground corn with rehydrated corn-grain silage with mucilage (RCSmucilage) in 415 g/kg because it provides better animal performance than ground corn (GC)—along with having a similar intake and digestion to it—due to better conservation of the silage at a lower cost when compared to commercial additives. ABSTRACT: 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 Δ(9)desaturase (C16) were higher (p = 0.027) in goat kids fed with GC and RCSmucilage, and Δ(9)desaturase (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.