Fecha/hora: 03/06/2024 05:50:00

Biblioteca(s): 	INIA La Estanzuela.	
Fecha corriente: 	12/10/2017	
Fecha de la última actualización: 	28/05/2018	
Autoria: 	SANTANA, A.; CAJARVILLE, C.; MENDOZA, A.; REPETTO, J.	
Afiliación: 	Universidad de la República (UdelaR)/ Facultad de Veterinaria; C. CAJARVILLE, Universidad de la República (UdelaR)/ Facultad de Veterinaria; ALEJANDRO FRANCISCO MENDOZA AGUIAR, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay; JOSE LUIS REPETTO CAPELLO, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay.	
Título: 	Combination of legume-based herbage and total mixed ration (TMR) maintains intake and nutrient utilization of TMR and improves nitrogen utilization of herbage in heifers.	
Año de publicación: 	2017	
Fuente/Imprenta: 	Animal , v. 11 n.4, p 616-624, 2017.	
DOI: 	10.1017/S1751731116001956	
Idioma: 	Inglés	
Notas: 	Article history: Received 18 September 2015 /7 Accepted 11 July 2016// First published online 11 October 2016.	
Contenido: 	Abstract: Diets combining herbage and total mixed rations (TMR) are increasingly used in temperate regions for feeding ruminants,
but little information is available regarding the effects on nutrient intake and digestion of this feeding management in beef cattle.
The aim of this study was to determine the effects of combining TMR (10% CP and 13% ADF), and legume-based herbage
(14% CP and 27% ADF) on intake, nutrient digestion, ruminal fermentation, microbial N flow and glucose and nitrogen
metabolism in heifers. The experiment was a 3 × 3 Latin square design replicated three times; each period lasted 18 days
(10 adaptation days and 8 measurement days). Nine cross-bred (Aberdeen Angus × Hereford) heifers (214 ± 18 kg) fitted with
permanent rumen catheters and housed in individual metabolic cages were assigned to one of three treatments: 24 h access to
TMR ( T), 24 h access to herbage ( H) or combined diets with 18 h access to TMR and 6 h access to herbage ( T + H). Data were
evaluated using a mixed model. Animals fed T+H ( TMR 71% and herbage 29%) diets tended to have a higher dry matter intake
as a proportion of their BW than animals fed T. The T+ H diet did not change ruminal fermentation (pH, N?NH3 and volatile fatty
acids) or the N metabolism relative to the T diet, but increased the glucagon concentration and altered glucose metabolism.
Conversely, animals fed T +H had increased purine derivatives excretion, increased N use efficiency for microbial protein synthesis
and decreased plasma urea and urinary N excretion relative to animals fed H diet. The use of combined diets led to consumption
of nutrients similar to a TMR diet, without reducing nutrient use and could improve N utilization compared with the
herbage-only diet.	
Palabras-Clave: 	FEEDING SYSTEMS; MEZCLA TOTAL RACION (TMR); MICROBIAL PROTEIN SYNTHESIS; MIXED DIETS; PARTIAL MIXED RATION; PASTURE; UTILIZACIÓN DE NUTRIENTES.	
Thesagro: 	Forrajes.	
Categoría del tema: 	--	
Registro original: 	INIA La Estanzuela (LE)	
Ejemplares: 	LE - (102241-1) - PXI - AP - DD -  -  -  - DIS