Relationship between performance, metabolic profile, and feed efficiency of lactating beef cows

Autor(es)

Souza, Luana Lelis ^[1] ; Zorzetto, Mariana Furtado ^[1] ; Terra Ricci, Tulio Jose ^[1] ; Canesin, Roberta Carrilho ^[1] ; Dias e Silva, Nhayandra Christina ^[2] ; Negrao, Joao Alberto ^[3] ; dos Santos Goncalves Cyrillo, Joslaine Noely ^[1] ; Zerlotti Mercadante, Maria Eugenia ^[1]

Afiliação do(s) autor(es)

^[1] Ctr Avancado Pesquisa Bovinos Corte, IZ, Sertaozinho, SP - Brazil

^[2] Univ Jose do Rosario Vellano UNIFENAS, Alfenas, MG - Brazil

^[3] Univ Sao Paulo, Fac Zootecnia & Engn Alimentos, Pirassununga, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: TROPICAL ANIMAL HEALTH AND PRODUCTION; v. 51, n. 7, p. 2045-2055, SEP 2019.
• Citações Web of Science: 0

Resumo

Twenty-seven Nellore cow-calf pairs were submitted for feed efficiency testing. The animals were weighed every 21 +/- 5 days to obtain metabolic body weight (BW0.75) and average daily gain (ADG). Subcutaneous fat thickness (SFT; at 20, 83, 146, and 176 days post-calving); milk yield and components (63, 85, and 151 days); levels of glucose, cholesterol, triglycerides, beta-hydroxybutyrate, albumin, urea, creatinine, calcium, phosphorus, magnesium, insulin, and cortisol (15, 41, 62, and 124 days); and ingestive behavior were evaluated. Residual feed intake was calculated for the first stage (RFI1; 21 to 100 days post-calving) and the second stage of lactation (RFI2; 100 to 188 days post-calving), and the cows were classified based on RFI1 as most efficient (RFI1 < 0) and least efficient (RFI1 > 0). Negative RFI1 cows consumed 1.3 kg/day of dry matter, or 9.77%, less than positive RFI1 cows. Most- and least-efficient cows did not differ in terms of subcutaneous fat thickness traits and milk yield or energy-corrected milk (ECM). Glucose (P = 0.0785), triglycerides (P = 0.0795), and phosphorus (P = 0.0597) concentrations were higher in the first stage of lactation in most-efficient cows. Maternal characteristics such as calf weight at birth and at 205 days and ADG were similar in most- and least-efficient cows. The most-efficient cows are more economic as they consume less feed for the same level of production. (AU)

• Processo FAPESP: 15/02066-4 - Avaliação fenotípica da eficiência alimentar e produtiva, e do perfil metabólico de matrizes nelore
• Beneficiário: Maria Eugênia Zerlotti Mercadante
• Modalidade de apoio: Auxílio à Pesquisa - Regular