Perfil metabólico e desenvolvimento da glândula mamária de novilhas leiteiras sob manejo para crescimento compensatório

• Autor(a) principal: Costa, Patrícia Barcellos
• Data de Publicação: 2012
• Outros Autores: Queiroz, Augusto César de, Rodrigues, Marcelo Teixeira, Magalhães, André Luiz Rodrigues, Zorzi, Karina, Mello, Renius, Silva, Márcia Maria Cândido da, Alves, Nadja Gomes
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UFLA
• Texto Completo: http://repositorio.ufla.br/jspui/handle/1/42721
• topic: Ionóforo; Metabólitos sanguíneos; Realimentação; Restrição; Vacas; Ionophore; Blood metabolites; Realimentation; Restriction; Cows

The objective of this trial was to compare the effect of compensatory growth regime on the metabolic profile and mammary gland development of dairy heifers. Twenty Brown-Swiss heifers averaging 200 kg of body weight and five months of age were used in a completely randomized design with a 2 × 2 factorial arrangement. The treatments were arranged in a factorial arrangement (2 × 2) and the animals were randomly allocated in each one of the combinations. The factor 1 consisted of the feeding regime (conventional and compensatory growth) and the factor 2, of the use or not of ionophore (200 mg of monensin/animal/day). The animals in the conventional regime received ad libitum feeding, while those in the compensatory growth regime were submitted to a nutritional management with two different periods: period of energy restriction (90 days) and realimentation period (60 days). Heifers submitted to the compensatory growth regime showed larger concentration of plasma urea nitrogen and lower DNA:RNA ratio in the mammary gland. When period was analyzed, the levels of high density lipoprotein (HDL) increased in the realimentation period, while the urea N decreased. In addition to the alteration in the levels of urea N, the energy balance to which the heifers in compensatory growth were submitted increased the non-esterified fatty acids. Blood glucose levels reduced in the animals in compensatory growth during the realimentation period. Supplementation with ionophore results in lower concentration of non-esterified fatty acids during the realimentation period.