Our research aims to:
- Address the gap between the current average 6-week In-Calf rate of 66% and the industry target of 78%
- Improve herd reproduction through better genetics by identifying new traits for cow fertility
- Determine the timing and causes of poor conception rates, and identify approaches to improve oocyte quality and embryo survival
- Characterise on-farm mortality and culling at different cow life stages in NZ dairy herds
- Develop new measures of cow longevity/survival related to good health and robustness, leading to accelerated genetic improvement in this trait
- Determine strategies that improve transition cow health by optimising metabolic, mineral or immune status
- Identify management solutions that improve reproduction by accelerating recovery of a healthy uterus after calving.
What have we found so far?
Inefficiencies currently cost the sector more than $1.5 billion per annum (p.a.). Through delivery of innovative solutions, we estimate $550 million p.a. can be recovered
Pre-mating cycling rates are important. The chance of conception increases by:
18% with each cycle before mating
13% with each extra week before mating read more
21% of cows are removed from the herd each year. 60-80% of removals are involuntary or avoidable
Blood BHBA* levels alone are not a good indicator of sub-clinical ketosis or underperformance in a pasture-based system read more
*β-hydroxybutyrate
Herds with low 6-wk In-Calf rates will obtain greater benefits from using High Fertility BV bulls than herds with high 6-wk In-Calf rates read more
High-Fertility Breeding Value (Fert BV) heifers reach puberty 25kg lighter and 21 days earlier than Low-Fertility BV heifers.
High-Fert BV cows had substantially greater 3-week submission rates, resulting in ~30% higher 6-week in-calf rates during first and second lactations read more
On average, 25% of cows have an unhealthy uterus one month before mating, which reduces cow fertility. This can range from 5-65% in individual herds read more
The main reasons cows are removed from the herd often arise from issues during the transition period:
- Reproduction 37%
- Udder Health 11%
- Health Disorders 31%
- Low production 8%
Feeding starch vs fibre to early lactation cows (if fed the same amount of energy) does not affect reproductive performance read more
Most pregnancy losses occur in the first week after breeding read more
This programme is funded by NZ dairy farmers through DairyNZ Inc. and by the Ministry of Business, Innovation and Employment (MBIE), with additional funding from AgResearch and in-kind support from LIC and Fonterra.
Research partners
This programme involves a multi-disciplinary team of research collaborators led by DairyNZ. The core team involves: AbacusBio, AgResearch, Cognosco (a division of Anexa Animal Health Centre), Massey University, Monash University, New Zealand Animal Evaluation Limited, Queensland University of Technology, University of Auckland, University of Queensland, VetEnt, VetSouth and Victoria University of Wellington.
