Effect of dietary crude protein degradability and corn processing on lactation performance and milk protein composition and stability
العنوان: | Effect of dietary crude protein degradability and corn processing on lactation performance and milk protein composition and stability |
---|---|
المؤلفون: | G.C. Ferreira, C. M. M. R. Martins, Marcos André Arcari, Carlos Augusto Fernandes de Oliveira, Marcos Veiga dos Santos, Bruna Gomes Alves, Katiéli Caroline Welter, D.C.M. Fonseca, Francisco Palma Rennó |
المصدر: | Repositório Institucional da USP (Biblioteca Digital da Produção Intelectual) Universidade de São Paulo (USP) instacron:USP |
بيانات النشر: | American Dairy Science Association, 2019. |
سنة النشر: | 2019 |
مصطلحات موضوعية: | Rumen, animal structures, Starch, Lactose, Zea mays, 03 medical and health sciences, chemistry.chemical_compound, Animal science, Latin square, ANÁLISE DE ALIMENTOS PARA ANIMAL, Casein, Lactation, Genetics, medicine, Animals, Dry matter, 030304 developmental biology, 0303 health sciences, Ethanol, 0402 animal and dairy science, food and beverages, 04 agricultural and veterinary sciences, Milk Proteins, Animal Feed, 040201 dairy & animal science, Diet, Milk, medicine.anatomical_structure, chemistry, Cattle, Female, Animal Science and Zoology, Composition (visual arts), Dietary Proteins, Food Science |
الوصف: | The present study aimed to evaluate the effect of crude protein degradability and corn processing on lactation performance, milk protein composition, milk ethanol stability (MES), heat coagulation time (HCT) at 140°C, and the efficiency of N utilization for dairy cows. Twenty Holstein cows with an average of 162 ± 70 d in milk, 666 ± 7 kg of body weight, and 36 ± 7.8 kg/d of milk yield (MY) were distributed in a Latin square design with 5 contemporaneous balanced squares, 4 periods of 21 d, and 4 treatments (factorial arrangement 2 × 2). Treatment factor 1 was corn processing [ground (GC) or steam-flaked corn (SFC)] and factor 2 was crude protein (CP) degradability (high = 10.7% rumen-degradable protein and 5.1% rumen-undegradable protein; low = 9.5% rumen-degradable protein and 6.3% rumen-undegradable protein; dry matter basis). A significant interaction was observed between CP degradability and corn processing on dry matter intake (DMI). When cows were fed GC with low CP degradability, DMI increased by 1.24 kg/d compared with cows fed GC with high CP degradability; however, CP degradability did not change DMI when cows were fed SFC. Similar interactions were observed for MY, HCT, and lactose content. When cows were fed GC diets, high CP degradability reduced MY by 2.3 kg/d, as well as HCT and lactose content, compared with low CP degradability. However, no effect of CP degradability was observed on those variables when cows were fed SFC diets. The SFC diets increased dry matter and starch total-tract digestibility and reduced β-casein (CN) content (% total milk protein) compared with GC diets. Cows fed low-CP degradability diets had higher glycosylated κ-CN content (% total κ-CN) and MES, as well as milk protein content, 3.5% fat-corrected milk, and efficiency of N for milk production, than cows fed high-CP degradability diets. Therefore, GC and high-CP degradability diets reduced milk production and protein stability. Overall, low CP degradability increased the efficiency of dietary N utilization and MES, probably due to changes in casein micelle composition, as CP degradability or corn processing did not change the milk concentration of ionic calcium. The GC diets increased β-CN content, which could contribute to reducing HTC when cows were fed GC and high-CP degradability diets. |
تدمد: | 0022-0302 |
URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::921d82fd440942a8a74a1339390f77c4 https://doi.org/10.3168/jds.2018-15553 |
حقوق: | OPEN |
رقم الأكسشن: | edsair.doi.dedup.....921d82fd440942a8a74a1339390f77c4 |
قاعدة البيانات: | OpenAIRE |
تدمد: | 00220302 |
---|