title: Effect of indoor energy restriction level and management on beef production in Belgian Blue double-muscled cow-calf pairs.
abstract: One hundred and twenty-six cows were involved to investigate the impact of energy (E) restriction (100%, 90%, 80% and 70% of total energy requirements) during the indoor period and two calf management systems (CMS: suckling or rearing). An E restriction during the indoor period resulted in a loss of body weight, even for E100, which was compensated during the re-alimentation period, but body weight remained lower in suckling than in non-suckling cows. The cows yielded 213 full-term gestations and 8 abortions. Abortion was not affected by E (p = 0.187) or CMS (p = 0.804). Calving interval was neither affected by E (p = 0.775) but tended to be longer in suckled cows (p = 0.087). E reduced body weight and body condition score (BCS) at the end of the calving interval, while CMS only affected BCS. E70 resulted in a higher colostrum yield than E100 and E 90 but immunoglobulin content was not affected (p = 0.759). Cow culling was not affected by E or CMS. It increased from 12.9% to 22.2% and 32.5% for cows with a BCS at parturition lower than 1.5 or between 1.5 and 2.0, or higher than 2 respectively. Calf birth weight was neither affected by E or CMS, but there was an interaction between E and dam age (p = 0.050). Increasing the E restriction tended to reduce calf survival (p = 0.089). Performance of the surviving calves was not affected by E, but suckling calves gained faster than rearing calves (p < 0.001). Beef production by the cow-calf pair was not different between energy levels (p = 0.738), but it was 10.8% lower for E70 than for E100 cows. It is not appropriate to apply an E restriction of more than 10-20% for maximum cow reproductive traits and calf performance.
authors.affiliation: ILVO-Animal Sciences, Melle, Belgium. leo.fiems@ilvo.vlaanderen.be
authors.forename: L O
authors.initials: LO
authors.lastname: Fiems
authors.forename: S
authors.initials: S
authors.lastname: De Campeneere
authors.forename: J L
authors.initials: JL
authors.lastname: De Boever
authors.forename: W
authors.initials: W
authors.lastname: Van Caelenbergh
authors.forename: D L
authors.initials: DL
authors.lastname: De Brabander
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000822:Animal Husbandry / Q000379:methods*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001835:Body Weight; D002417:Cattle / Q000502:physiology*; D004032:Diet / Q000662:veterinary; D004734:Energy Metabolism; D005260:Female; D005508:Food Deprivation; D006799:Housing, Animal; D012098:Reproduction