Effects of rumen-protected choline supplementation on metabolic and performance responses of transition dairy cows

Autor(es)

Leiva, T. ^[1] ; Cooke, R. F. ^[2] ; Brandao, A. P. ^[1] ; Marques, R. S. ^[2] ; Vasconcelos, J. L. M. ^[1]

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ, Dept Anim Prod, BR-18168000 Botucatu, SP - Brazil

^[2] Oregon State Univ, Eastern Oregon Agr Res Ctr, Burns, OR 97720 - USA

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF ANIMAL SCIENCE; v. 93, n. 4, p. 1896-1904, APR 2015.
• Citações Web of Science: 13

Resumo

The objective of this experiment was to compare metabolic and milk production parameters in dairy cows supplemented and nonsupplemented with rumen-protected choline (RPC) during the transition period. Twenty-three nonlactating, multiparous, pregnant Holstein cows were ranked by BW and BCS 21 d before expected date of calving and immediately were assigned to receive (n = 12) or not receive (control; n = 11) RPC until 45 d in milk (DIM). Cows supplemented with RPC received (as-fed basis) 50 and 100 g/d of RPC (18.8% choline) before and after calving, respectively. Before calving, cows were maintained in 2 drylot pens according to treatment with ad libitum access to corn silage, and individually they received (as-fed basis) 3 kg/cow daily of a concentrate. Upon calving, cows were moved to 2 adjacent drylot pens according to treatment, milked twice daily, offered (as-fed basis) 35 kg/cow daily of corn silage, and individually received a concentrate formulated to meet their nutritional requirements after milking. The RPC was individually offered to cows as a topdressing into the morning concentrate feeding. Before calving, cow BW and BCS were recorded weekly, and blood samples were collected every 5 d beginning on d - 21 relative to expected calving date. Upon calving and until 45 DIM, BW and BCS were recorded weekly, individual milk production was recorded daily, and milk samples were collected once a week and analyzed for fat, protein, and total solids. Blood samples were collected every other day from 0 to 20 DIM and every 5 d from 20 to 45 DIM. Based on actual calving dates, cows receiving RPC or control began receiving treatments 16.8 +/- 1.7 and 17.3 +/- 2.0 d before calving, respectively. No treatment effects were detected (P >= 0.18) on postpartum concentrate intake, BW and BCS, or serum concentrations of cortisol, beta-hydroxybutyrate, NEFA, glucose, and IGF-I. Cows supplemented with RPC had greater (P <= 0.01) mean serum haptoglobin and insulin concentrations compared with control. Cows supplemented with RPC had greater (P < 0.01) milk protein, total solids (P < 0.01), and milk fat concentrations (P = 0.09) compared with control. No treatment effects were detected (P >= 0.43) for milk yield parameters, such as fat-corrected or solids-corrected milk yield. In conclusion, supplementing RPC to transition dairy cows increased haptoglobin and insulin concentrations and benefited milk composition. (AU)

• Processo FAPESP: 12/25390-3 - Efeito da densidade nutricional da dieta e suplementação com cromo nas concentrações séricas de glicose, insulina, ácidos graxos não esterificados, triacilglicerol e IGF-1, em vacas de leite lactantes
• Beneficiário: Tiago Leiva
• Modalidade de apoio: Bolsas no Brasil - Mestrado