Título:	Age-month factors mature equivalente factors for three yield traits for non-registered and registered cattle.
Autor:	DURAES, M. C. KEOWN, J. F.
Afiliación:	MARCUS CORDEIRO DURAES, CNPGL; JEFFREY F. KEOWN, UNIVERSITY OF NEBRASKA.
Año:	1991
Referencia:	Revista Brasileira de Genética, v. 14, n. 3, p. 713-728, 1991.
Descripción:	Agc-momh adjustment factors for registered and non-registered cows were estimated for milk, fat and protein yields. Records used in analysis considered 419,860 lactation records of Holstein cows freshening from 1983 to 1985 in nine states of the Mid-West region of the United States: Arkansas, Illinois. Jowa, Kansas, Missouri, Nebraska, North Dakota, Oklahoma and South Dakota. The mixed model used todescribe the data contained fixed effects due to an overall mean, age-month of calving for non-registered andmgjstcled cows, the herd-year; and as random effects, cow and error terms. There were 30 age groups by 12 months of freshening for a total of 720 age-month estimates for each of the three traits. The ratio ofdze/dzc = 13/12 based on a repeatability of .48 for milk yield was used. Results showed a definitive age by month interaction. Age is more important for younger cows while month effects assumed more importance for mature cows. Multiplicative age-month adjustment factors were developed and are presented along with plots of the age-month factors for milk, fat and protein yield. Factors differed for the three yield traits. Milk and fat factors were larger than the corresponding factors for protein. There wasa general trend for factors from non-registered to be larger than those from registered cows for same ageand months of calving.
Thesagro:	Bovino Idade Leite Raça
NAL Thesaurus:	age cattle
Palabras clave:	Dairy Holandesa PC-PO Fatores Ajustamento
Tipo de Material:	Artigo de periódico
Acceso:	openAccess
Aparece en las colecciones:	Artigo em periódico indexado (CNPGL)