Data/hora: 05/06/2024 04:46:56

Provedor de dados: 	96	
País: 	Brazil	
Título: 	Intake, digestibility and nitrogen use efficiency in crossbred F1 Holstein × Zebu grazing cows	
Autores: 	Santos,Stefanie Alvarenga; Valadares Filho,Sebastião de Campos; Detmann,Edenio; Valadares,Rilene Ferreira Diniz; Ruas,José Reinaldo Mendes; Prados,Laura Franco; Amaral,Paloma de Melo; Mariz,Lays Débora Silva.	
Data: 	2012-04-01	
Ano: 	2012	
Palavras-chave: 	Brachiaria decumbens; Crossbreeding; Milk production; Performance.	
Resumo: 	The objective of this study was to evaluate intake, digestibility and nitrogen (N) compounds use efficiency in F1 Holstein × Zebu grazing cows. Eighteen crossbred cows (six Holstein × Gir, six Holstein × Guzerat, and six Holstein × Nellore) were used in the experiment, constituting three experimental treatments in simple random samples, under the same feeding conditions. At the estimation of individual intake at grazing, titanium dioxide was used for estimating fecal excretion and indigestible neutral detergent fiber, in order to determine pasture intake. There was effect of the lactation period on nutrient intake, except for the intakes of dry matter (DM), organic matter (OM) and total digestible nutrients (TDN) in % of body weight (BW), as well as those of non-fibrous carbohydrates (NFC), in kg. The digestibility coefficients of crude protein (CP), neutral detergent fiber corrected for ash and protein (NDFap) and the contents of TDN varied in function of the lactation period, whereas the coefficients of digestibility of DM, ether extract (EE) and OM did not present such effect. The total milk production projected at 305 days of lactation for Holstein × Gir cows was superior in relation to Holstein × Guzerat and Holstein × Nellore cows. The excretion of urea into urine and of urea N into the milk and the plasma presented quadratic behavior in function of the lactation period. The utilization of the genetic group from Holstein × Zebu grazing cows does not cause alterations in intake, nutrient digestibility or nitrogen use efficiency; however, there is variation in function of the lactation period. Holstein × Gir cows presented greater accumulated production during lactation and persistence, followed by Holstein × Guzerat and Holstein × Nellore cows.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982012000400027	
Editor: 	Sociedade Brasileira de Zootecnia	
Relação: 	10.1590/S1516-35982012000400027	
Formato: 	text/html	
Fonte: 	Revista Brasileira de Zootecnia  v.41 n.4 2012	
Fonte: 	info:eu-repo/semantics/openAccess