The New Zealand dairy industry is a seasonal production system, requiring cows to calve annually to begin lactation. With an average herd replacement rate of approximately 22%, a large proportion of calves born each year are surplus to dairy replacement requirements (DairyNZ, 2021; Ministry of Primary Industries, 2022). As the industry seeks to move away from the current surplus calf model, there is an increasing need to develop profitable and sustainable pathways for these non-replacement calves. This raises an important question: how can greater value be created from surplus calves to improve both industry profitability and resource utilisation?
This project investigates the potential for genetic improvement in feed efficiency as a possible solution. The dairy industry faces a challenge of maximising the productivity and profitability of excess calves. To combat this, an increasing proportion of dairy cows are mated to beef sires. Improving feed efficiency of these sires and therefore the resulting progeny through genetic selection, can offer a promising solution. Enabling animals to convert feed into production more effectively while reducing production costs and environmental impacts.
A review of the literature was conducted to determine current knowledge and research available on feed efficiency, as well as identify opportunities for further development.
Trial data comprising of 371 animals, all tested using the same Vytelle SENSE feed efficiency facility, was analysed. Animals displayed normally distributed variation for Residual Feed Intake with a mean of 0.00 ± 0.68 with a range of 4.02. The trial results support findings from the literature, animals with improved feed efficiency consume less feed and have an ability to maintain growth and production.
Semi structured interviews were conducted on 17 industry stakeholders from a range of positions in the supply chain. Open-ended questions were asked to explore the motivations and barriers influencing beef on dairy strategies currently in place in New Zealand and Australia. As well as the potential for new growth in this space through the incorporation of feed efficiency and the implications of this on the wider industry.
Key Findings include:
The benefits of feed efficiency are achieved when animals maintain the same average daily weight gain but consume lower than average dry matter intake per day. Bringing the cost of production down on a per kg of liveweight basis. Feed efficient animals are therefore more profitable even if growth rates are similar.
Modelling conducted indicates that reducing the mean Average Daily Dry Matter Intake (ADDMI) of New Zealand’s beef on dairy population by one kilogram of dry matter per animal per day could result in annual feed cost savings of approximately $51 million, while also freeing up enough feed to support an additional 87,500 animals.
Feed efficiency traits are heritable; improvements are permanent and can be transferred across generations.
There is sufficient variation in feed efficiency within the population to enable effective selection to occur.
A strong correlation between improved feed efficiency and a reduction in enteric methane production enables feed efficiency to potentially be implemented as a methane mitigation strategy.
Recommendations
- Further Research is required to: Develop a robust genomic model, to further investigate the possibility of utilising wearable technologies to record proxy traits, and to develop a better understanding of the linkage between feed efficiency to enteric methane production
- Industry education to demonstrate the value of improved feed efficiency and increase awareness of feed efficiency traits
- Develop a supply chain initiative for strategic sire selection
- Position feed efficiency as a dual-purpose productivity and emissions reduction trait
- Strengthen vertical integration and incentive signals
Emma Owen
