Growth, blood metabolites and hormones in calves fed diets with different amounts of energy and protein during the pre- or post-weaning periods
We investigated the effects of diets differing in energy and protein concentrations given during pre- and post-weaning on hormone and metabolite levels in association to parameters of growth. Sixteen Aberdeen Angus calves four-day-old were allocated in individual pens during 105 days in a randomized...
| Autores: | , , , , , , , |
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| Formato: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2012 |
| País: | Argentina |
| Recursos: | Consejo Nacional de Investigaciones Científicas y Técnicas |
| Repositorio: | CONICET Digital (CONICET) |
| Idioma: | inglés |
| OAI Identifier: | oai:ri.conicet.gov.ar:11336/19859 |
| Acesso em linha: | http://hdl.handle.net/11336/19859 |
| Access Level: | acceso abierto |
| Palavra-chave: | CALVES EARLY WEANING ENERGY GROWTH HORMONES METABOLITES PROTEIN https://purl.org/becyt/ford/4.2 https://purl.org/becyt/ford/4 |
| Resumo: | We investigated the effects of diets differing in energy and protein concentrations given during pre- and post-weaning on hormone and metabolite levels in association to parameters of growth. Sixteen Aberdeen Angus calves four-day-old were allocated in individual pens during 105 days in a randomized complete design. Animals consumed ad libitum various diets differing in proportion of energy and protein (A: 80% of concentrate, 20% alfalfa hay; B: 60% concentrate, 40% of alfalfa hay; C: 40% concentrate, 60% alfalfa hay, and D: 20% concentrate, 80% alfalfa hay). Also, calves consumed milk substitute up to 60-day-old day. Serum growth hormone and cortisol levels were not altered with diet changes (P > 0.05) neither during the pre- nor the post-weaning periods. Plasma insulin concentration average daily intake, glucose and thyroid hormone levels, and concentrations of ammonia nitrogen and propionic acid were greater (P < 0.01) for diets having higher than lower energy and protein levels during the post-weaning but not during the pre-weaning period. These results suggest inclusion of higher amounts of concentrate in the diet of weaned calves. |
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