Associate Professor Geoff Hinch
University of New England
Tel: 02 6773 2202
The aim of this project is to develop practical management, selection and genetic technologies that improve reproductive efficiency and that are rapidly adopted by 'early majority type' producers, or in other words, successful, pragmatic enterprises that are seeking safe incremental improvement to their business. Increasing reproduction rate on farm is potentially difficult or complex since there is no single, easy to implement strategy that will deliver most of the benefits. The focus in the first two years was to identify the nature and extent of the lamb and weaner survival problem, to review current knowledge on management practices to improve survival, to undertake primary market research to determine solutions to improve lamb and weaner survival that may be compelling for different producers, to develop messages and information products and establish delivery channels and processes to reach priority target groups. The focus of the project in year five will be:
a) Ongoing National implementation of a series of adoption strategies targeted at producers who have already shown some interest in reproduction by adopting
pregnancy scanning. This includes (i) Generic communications to raise awareness of opportunities to improve reproduction rate by genetic improvement, ewe lifetime
selection and nutritional management, and ensuring that this project’s strategies are included with other industry initiatives such as Making More from Sheep and AWI/MLA producer networks; (ii) Engagement of pregnancy scanners and their clients that account for more than 40% of the national ewe flock and have expressed a willingness to collaborate with this project; and (iii) Intensive support for high impact producers to adopt practice change through short course-small group training approaches (Lifetime Ewe Management and High Performance Weaners).
b) Ongoing data collection from Information Nucleus flocks to allow new trait identification for reproductive parameters (particularly lamb survival) and to report on the results of postgraduate research related to improving reproductive efficiency. The project will work closely with Project 1.1. and Project 4.1. to assist with analysis and interpretation of data from the Information Nucleus flocks (and other sources) related to reproduction and to identify potential ewe, lamb and weaner traits to target for selection to improve reproduction efficiency and fitness, both in current and future generations in different environments. The project will also undertake an analysis of relationships between reproductive success of ewe lambs and liveweight change in the diverse range of genotypes of different seasonality, from both with the Information Nucleus and other industry flocks.
The business case for Project 1.2 is based on delivery of Outcome 2 (Improved animal welfare and increased reproduction rates) and part of Outcome 1 (Improved sheep management and decision making). These will be addressed by improved management and selection of ewes, lambs and weaners and is expected to result in 10% increase in net reproduction rates and/or productivity in more than 20% of Australian ewes. This equates to an extra one million lambs per year reaching productive use - slaughter or first shearing. The business case relates largely to an industry practice change target, which is reflected in the emphasis on practice change rather than research.
The last 20 years has seen a steady decline in the size of the national sheep flock, exacerbated by poor seasonal conditions and modest wool prices and attractive returns from prime lamb production. At the same time, there has been a steady increase in the number of lambs slaughtered even as the sheep flock has fallen. Improving reproduction rate is an important pathway to maintaining a sustainable and viable sheep industry that can also lead to improvements in profitability for some enterprises. The average number of lambs weaned per 100 ewes joined has remained at around 75 to 80 over this period. It is estimated that about 25% of lambs born do not survive to weaning and a further 5 to 10% of those that survive die in the 12 months after weaning. This equates to about 10 million lambs and weaners lost each
year and this represent a major cost in lost production to industry and a potential animal welfare threat. Increases in reproduction rate can be delivered through increasing fertility, increasing litter size and improving the consistency of performance between years within a ewe’s lifetime. Management practices such as improving nutrition at key times to 'at risk' animals can significantly reduce these losses but they have not been adopted on a large scale. It is clear that many of the management technologies and practices that have been promoted have not represented compelling propositions to a significant proportion of the target audience.
In addition to management interventions there are other options to increase the reproduction rate of sheep. This includes ewe lifetime selection or using pregnancy scanning information to cull low performing ewes from the flock and extend the life of high performing ewes. This project will use parameters derived from analysis of existing data sets to expand computer selection models to identify selection criteria that will increase reproductive performance within the current generation, taking account of other production traits, liveweight or condition score and previous reproductive performance. This project will also take advantage of the unique
opportunity presented by the Information Nucleus Flock to identify ’indicator’ traits linked to reproductive fitness and develop new ways to genetically improve the flock for reproduction rate.