Data/hora: 23/09/2024 03:22:21

Biblioteca(s): 	Embrapa Pecuária Sul.	
Data corrente: 	06/12/2022	
Data da última atualização: 	06/12/2022	
Autoria: 	MARÍN GÓMEZ, A.; LACA, E. A.; BALDISSERA, T. C.; PINTO, C. E.; GARAGORRY, F. C.; ZUBIETA, A. S.; BREMM, C.; BINDELLE, J.; CARVALHO, P. C. de F.	
Afiliação: 	ALEJANDRA MARÍN GÓMEZ, Federal University of Rio Grande do Sul; EMILIO A. LACA, University of California; TIAGO CELSO BALDISSERA, EPAGRI; CASSIANO EDUARDO PINTO, EPAGRI; FABIO CERVO GARAGORRY, CPPSUL; ANGEL S. ZUBIETA, Federal University of Rio Grande do Sul; CAROLINA BREMM, Federal University of Rio Grande do Sul; JERÔME BINDELLE, Liège University; PAULO CÉSAR DE FACCIO CARVALHO, Federal University of Rio Grande do Sul.	
Título: 	Determining the pre-grazing sward height of Kikuyu grass (Cenchrus clandestinus - Hochst. ex Chiov.) for optimizing nutrient intake rate of dairy heifers.	
Ano de publicação: 	2022	
Fonte/Imprenta: 	PLos One, v. 17, n. 7, e0269716, July 2022.	
DOI: 	https://doi. org/10.1371/journal.pone.0269716	
Idioma: 	Inglês	
Conteúdo: 	Understanding the grazing process and animal response to sward structures (e.g., sward height) is key to setting targets for efficient grazing management. We hypothesized that the short-term intake rate (STIR) of dry matter (DM) and digestible organic matter (OM) by dairy heifers is maximized with Kikuyu grass (Cenchrus clandestinus?Hochst. ex Chiov.) of intermediate sward heights. The treatments consisted of five pre-grazing sward heights (10, 15, 20, 25, and 30 cm) randomly assigned to two of ten paddocks. The experimental design included two measurements of each paddock at different periods and times of day. Three Holstein heifers (440 ± 42 kg body weight) were used to determine the STIR, which was estimated using the double-weighing technique with correction for insensible weight losses. The bite mass (BM), bite rate (BR), sward structural characteristics, and nutritional value of herbage samples were assessed. The data were analyzed using mixed models with a factorial arrangement of five sward heights, two times of day, and two evaluation periods. The sward height of Kikuyu grass that maximized both STIRs was approximately 20 cm. The STIR of the DM was 30% and 15% lower than the maximum in the shortest and tallest swards tested, respectively. In swards shorter than 20 cm, the STIR was lower because the BM decreased with sward height, whereas in those greater than 20 cm, the lower BM and STIR of DM was explained by a decrease in bulk density and bite volume. The top stratum was composed mainly of highly digestible leaf blades with similar nutrient content across sward heights; therefore the STIR of digestible OM was also maximized at 20 cm. Hence, the optimal pre-grazing sward height of Kikuyu grass should be managed at 20 cm under rotational stocking systems to maximize nutrient intake rate of dairy heifers.	
Thesagro: 	Gado Leiteiro; Pastagem.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Pecuária Sul (CPPSUL)	
Exemplares: 	CPPSUL - (14957-1) - UPC - AP - DD -  -  -  - DIS