ON FARM SHEEP FEEDBASE f The facts onflushing Providing ewes with “We found increases of up to 33 Gervaise said the reproductive nutritional supplementation additional lambs scanned per 100 ewes response to increased nutrition prior to joining – known joined, but more generally in the range from green feed appeared to be as flushing – can improve of 10–30 additional lambs scanned per independent of live weight at joining. lambing percentages through 100 ewes joined. “It appears to be similarly independent an increase in ovulation rate. “The ewes only needed to be on green of condition score,” she said. While research has shown this feed (minimum of 350kg/DM/ha) for a “The opportunity cost of flushing to be the case, how it plays out week before joining, and a week into ewes on green feed versus finishing on farm using typical grazing joining, for the benefits to show up. lambs or growing out weaners is a management and available feed “The largest influence on increasing factor that needs to be considered is less well known. reproductive efficiency from short or before joining. For example, if there’s long‑term flushing on green fed was a lower available feedbase due to MLA worked with Agriculture Victoria to through having more ewes producing seasonal conditions, then it could be establish 32 Producer Demonstration twin foetuses. more profitable to flush ewes than Sites to investigate the impact of short finish lambs.” and long‑term flushing with green feed “Overall, there were more pregnant or lupins, compared to ewes grazing ewes at some sites, but this was less of Lupins were also shown to be effective dry pasture. an influence on reproductive efficiency.”for flushing ewes and increasing While a short flush (two weeks total) reproduction rates, but lupins can be Trials were conducted between 2013 difficult to obtain in some areas and and 2017 on farms in Victoria, NSW was found to be adequate to increase tend to be less cost effective compared and SA. More than 22,000 crossbred, reproductive rates, Gervaise said to available green feed. ■ composite and Merino ewes were conception and reproductive rates were included in the study and were joined not negatively affected when ewes between late December and March for grazed lucerne for the entire joining RESEARCH IN autumn/winter lambing. period (long flush). REVIEW Gervaise Gaunt, Agriculture Victoria, “Further work would be needed to said an important component of the determine when grazing lucerne PROJECT NAME project was that it used whatever green throughout joining is a feasible and Participatory research evaluating feed (lucerne, rape, millet or green economic option,” she said. and demonstrating the impact of pasture) was available on farm. The green feed (particularly lucerne) benefits were clear at most sites. “However, grazing lucerne should on sheep conception be avoided if fungal disease is “Short‑term flushing with green present or if the lucerne is stressed RESEARCH ORGANISATIONS feed provides a strong likelihood of by aphid attack, as it can produce a Agriculture Victoria, MLA achieving impressive reproductive chemical called coumestan (a type of FUNDING ORGANISATIONS benefits compared to ewes grazing dry phytoestrogen) that can have an impact Agriculture Victoria, MLA pasture,” Gervaise said. on ewe fertility.” GOAL To demonstrate and validate scientific research investigating the impact of short and long‑term flushing with green feed (including lucerne) using grazing management ‘typical’ to that farm DURATION 2013–2017 Gervaise Gaunt Agriculture Victoria P: 02 6030 4571 E: gervaise.gaunt@ecodev.vic. gov.au mla.com.au/greenflush Short‑term flushing of ewes using any green feed can significantly increase reproductive ratesagriculture.vic.gov.au and search by increasing the number of twins born. Photo: Gervaise Gaunt ‘diseases of lucerne’ 30