Evaluation of mating systems involving five breeds for integrated beef production systems: I. Cow-calf segment.
J Anim Sci
; 70(3): 689-99, 1992 Mar.
Article
em En
| MEDLINE
| ID: mdl-1563995
ABSTRACT
Deterministic computer models were used to simulate the cow-calf segment of an integrated production system. Angus, Charolais, Hereford, Limousin, and Simmental breeds were included in three mating systems pure-breeding (PB) or two- (2R) or three-breed (3R) rotational crossbreeding. Breed data were taken from the literature. Herds were evaluated over the production year. Sires represented breed averages and were available from sources outside their herds, and 100 replacement heifers were saved annually. Females in 3R had the highest average energy requirements (8,144 Mcal of ME.cow-1.yr-1) and production costs ($322.31.cow-1.yr-1), and PB females had the lowest average requirements (7,748 Mcal of ME.cow-1.yr-1) and costs ($313.2.cow-1.yr-1). Purebred systems were the least biologically and economically efficient (64.9 Mcal of ME/kg of steer equivalent, $2.35/kg of steer equivalent), respectively, and 3R systems were the most efficient (56.6 Mcal of ME/kg of steer equivalent, $1.95/kg of steer equivalent). On average, 3R systems were more efficient biologically and economically than 2R systems. However, some 2R systems were as efficient as some 3R systems. Crossbred combinations containing Angus and(or) Hereford ranked more biologically and economically efficient than other breed combinations. Conversely, British purebreds ranked more biologically efficient, whereas Continental purebreds ranked more economically efficient.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cruzamento
/
Bovinos
/
Cruzamentos Genéticos
Tipo de estudo:
Health_economic_evaluation
Limite:
Animals
/
Pregnancy
Idioma:
En
Revista:
J Anim Sci
Ano de publicação:
1992
Tipo de documento:
Article