Journal cover Journal topic
Archives Animal Breeding Archiv Tierzucht
Journal topic

Journal metrics

Journal metrics

  • IF value: 0.991 IF 0.991
  • IF 5-year value: 1.217 IF 5-year
    1.217
  • CiteScore value: 2.0 CiteScore
    2.0
  • SNIP value: 1.055 SNIP 1.055
  • IPP value: 1.27 IPP 1.27
  • SJR value: 0.425 SJR 0.425
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 28 Scimago H
    index 28
  • h5-index value: 13 h5-index 13
Supported by
Logo Leibniz Institute for Farm Animal Biology Logo Leibniz Association
Volume 58, issue 1
Arch. Anim. Breed., 58, 127–135, 2015
https://doi.org/10.5194/aab-58-127-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
Arch. Anim. Breed., 58, 127–135, 2015
https://doi.org/10.5194/aab-58-127-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.

  26 Mar 2015

26 Mar 2015

Biological efficiency profiles over the lactation period in multiparous high-producing dairy cows under divergent production systems

S. A. Ross1, M. G. G. Chagunda1, C. F. E. Topp1, and R. Ennos2 S. A. Ross et al.
  • 1Scotland's Rural College (SRUC), Edinburgh, UK
  • 2School of Biological Sciences, University of Edinburgh, Edinburgh, UK

Abstract. The study examined variation in energetic-efficiency profiles among production systems and cow parities. Further, the correlation between cows' body condition score (BCS) and energetic efficiency over the lactation period was determined. Biological efficiency was defined using four measures of production efficiency and two measures of energetic efficiency. The following were measures of energetic efficiency: the net energy intake required to produce 1 kg milk solids (NEin / MS) and the proportion of net energy utilized for milk production after accounting for maintenance (NElact / (NEin- NEm)). Seven years of data were gathered from a total of 595 Holstein-Friesian cows in a long-term genetics × feeding–management interaction project. Two feeding regimes – High forage (HF) and Low forage (LF) – were applied to each of two genetic lines (Control (C) and Select (S)), giving four dairy production systems: Low Forage Control (LFC), Low Forage Select (LFS), High Forage Control (HFC) and High Forage Select (HFS). LFS was the most efficient system using all measures. Variation in the rate and scale of change at which the cows' energetic efficiency declined over lactation was significantly different (P < 0.001) amongst different dairy production systems and parities. Loss of efficiency over the lactation period was lower in Select cows than in Control cows and increased with parity. The trajectory of energetic-efficiency profiles was influenced by cow genetic line, and yet the level of the efficiency profile was influenced by the feeding regime. There was a strong relationship between BCS and energetic efficiency. Continued in situ monitoring of cows' biological efficiency may enable optimal management of dairy systems.

Download
Citation