Feed efficiency of pen fed Hereford, Angus X Hereford and Friesian X Hereford cows

Graham, J.F.; Clark, A.J.

Proceedings of the Australian Society of Animal Production 17: 405

1988


Accession: 001594767

Download citation:  
Text
  |  
BibTeX
  |  
RIS

Article/Abstract emailed within 1 workday
Payments are secure & encrypted
Powered by Stripe
Powered by PayPal

Abstract
The effect of genotype and feeding level on feed efficiency for maintenance was examined during pregnancy and lactation in Hereford (H X H), Aberdeen-Angus X Hereford (A X H) and Friesian X Hereford (F X H) cows (n = 41) calving in autumn of 1985 and 1986. Cows were fed at 3 levels (maintenance (M), M x 1.25 and M x 0.75) during the final 8 weeks of pregnancy and 2 levels (M plus feed for 4 kg or 8 kg milk/cow daily) during the first 8 weeks of lactation. Daily feed allowances were calculated using the 24-h fasted liveweights (FLW) of each cow at the start of each feeding period and adjustments made for stage of pregnancy and milk production. Metabolizable energy of feed was calculated from digestibility in vitro. Maintenance energy (MEm) was calculated using the formula MEm = intake energy - energy used for pregnancy or milk production +or- energy of liveweight change (LWC) (assuming constant efficiencies between genotypes of feed use for foetal growth, LWC and milk production). There was no significant effect of genotype on MEm during pregnancy or lactation but maintenance efficiency tended to decrease as feeding level increased.