Silva Camila S da, Gama Marco A S, Silva Erick A M, Ribeiro Emília F, Souza Felipe G, Monteiro Carolina C F, Mora-Luna Robert E, Oliveira Júlio C V, Santos Djalma C, Ferreira Marcelo de A
Department of Animal Science, Federal Rural University of Pernambuco, Dom Manoel de Medeiros Street, Dois Irmãos, Recife 52171-900, Brazil.
Embrapa Southeast Livestock, Washington Luiz Road, Km 234, São Carlos 13560-970, Brazil.
Animals (Basel). 2023 Feb 6;13(4):568. doi: 10.3390/ani13040568.
We evaluated the performance, milk composition, and milk fatty acid profile of cows fed diets composed of cactus cladodes ( [Haw.] Haw), sugarcane bagasse and increasing levels of full-fat corn germ (FFCG). We hypothesized that ground corn can be effectively replaced by FFCG when cactus cladodes and sugarcane bagasse are used as forage sources. The cows were randomly distributed into two 5 × 5 Latin Squares and fed five diets in which ground corn was progressively replaced with full-fat corn germ (FFCG; 0%, 25%, 50%, 75%, or 100% of substitution). Adding FFCG to the diet increased milk production and milk fat content and reduced milk protein content. Overall, FFCG reduced the proportion of saturated FAs and increased mono- and polyunsaturated FAs in milk, including CLA isomers. In addition, activity indices of stearoyl-CoA desaturase were reduced by increasing levels of FFCG. We conclude that the substitution of corn for FFCG in diets based on cactus cladodes and sugarcane bagasse positively modifies the FA profile of milk and could add commercial value to milk products (e.g., CLA-enriched milk). In addition, the milk fat response indicates that the basal diet was favorable to the rumen environment, preventing the shift commonly associated with milk fat depression.
我们评估了以仙人掌茎片（[Haw.] Haw）、甘蔗渣和不同水平的全脂玉米胚芽（FFCG）组成的日粮喂养奶牛的生产性能、乳成分和乳脂肪酸谱。我们假设，当以仙人掌茎片和甘蔗渣作为饲料来源时，磨碎的玉米可以被全脂玉米胚芽有效替代。奶牛被随机分配到两个5×5拉丁方中，饲喂五种日粮，其中磨碎的玉米逐渐被全脂玉米胚芽（FFCG；替代率为0%、25%、50%、75%或100%）替代。向日粮中添加FFCG可提高产奶量和乳脂肪含量，并降低乳蛋白含量。总体而言，FFCG降低了乳中饱和脂肪酸的比例，增加了单不饱和脂肪酸和多不饱和脂肪酸的比例，包括共轭亚油酸异构体。此外，随着FFCG水平的提高，硬脂酰辅酶A去饱和酶的活性指数降低。我们得出结论，在以仙人掌茎片和甘蔗渣为基础的日粮中，用FFCG替代玉米可积极改变乳的脂肪酸谱，并可为乳制品（如富含共轭亚油酸的牛奶）增加商业价值。此外,乳脂肪反应表明基础日粮有利于瘤胃环境，可防止通常与乳脂肪降低相关的变化。
