Data/hora: 22/09/2024 19:00:24

Biblioteca(s): 	Embrapa Pantanal.	
Data corrente: 	22/01/2015	
Data da última atualização: 	24/03/2016	
Autoria: 	BAILEY, J. C.; TEDESCHI, L. O.; MENDES, E. D. M.; SAWYER, J. E.; CARSTENS, G. E.	
Afiliação: 	J. C. BAILEY, Department of Animal Science, Texas A&M University, College Station; L.O.TEDESCHI, Department of Animal Science, Texas A&M University, College Station; EGLEU DIOMEDES MARINHO MENDES, CPAP; J. E. SAWYER, Department of Animal Science, Texas A&M University, College Station; G. E. CARSTENS, Department of Animal Science, Texas A&M University, College Station.	
Título: 	Technical note: evaluation of bimodal distribution models to determine meal criterion in heifers fed a high-grain diet.	
Ano de publicação: 	2012	
Fonte/Imprenta: 	Journal of Animal Science, v. 90, n. 8, p. 2750-2753, aug. 2012.	
DOI: 	10.2527/jas2011-4634	
Idioma: 	Inglês	
Conteúdo: 	Meals are clusters of feedbunk visit (BV) events that are differentiated from the next meal by a nonfeeding interval that is longer compared with the nonfeeding intervals within a meal. The longest nonfeeding interval considered to be part of a meal is defi ned as the meal criterion. The objective of this study was to determine which combination of 2 probability density functions [(PDF): Gaussian normal (G), Weibull (W), Log-Normal, Gamma, and Gumbel] used in a bimodal distribution model had the best fit of nonfeeding interval data collected in beef heifers. Feeding behavior traits (572,627 total BV events) were measured in 119 heifers fed a high-grain diet (3.08 Mcal ME/kg DM), using a GrowSafe system for 66 d. The frequency and duration of BV events averaged 75 ± 15 events/d and 73.0 ± 22.3 min/d, respectively. The bimodal PDF combinations were fi tted to the log10-transformed interval lengths between BV events for each animal, using R mixdist package (2.13). The Akaike Information Criterion (AIC) was used to assess goodness of fi t of the 25 bimodal PDF combinations. The PDF model with the least AIC value was selected as the best fi t for each individual. A x2 analysis of the selected best PDF distribution across individuals revealed that 78.2% of the heifers best fi t were G-W or W-W PDF models. The likelihood probability estimates were calculated from the average AIC deviation of each model from the standard G-G model. The G-W likelihood probability estimate was greater (P = 0.001) than the W-W combination (0.997 vs. 0.727). Our analysis indicated the G-W model had a statistically better fi t and is most likely the best approach to defi ne meal criterion in beef heifers fed high-grain diets.	
Palavras-Chave: 	Meal criterion.	
Thesagro: 	Bovino; Gado; Nutrição animal.	
Thesaurus Nal: 	beef cattle; feeding behavior.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Pantanal (CPAP)	
Exemplares: 	CPAP - (59235-1) - UPC - AP - PP - SP18031 -  - 18031 - DIS