John Young
Executive Summary
The WA flock is at a historically low level, however, sheep profitability is at record highs so rebuilding the state flock is an industry priority. Minimising ewe losses is a necessary component of the flock rebuilding. As a result of the feed shortage and possible grain shortage with high prices likely due to demand for grain from the east coast, local farmers may be tempted to underfeed their ewes during the summer/autumn period. Awareness and good information regarding the cost of mis-managing ewe nutrition will help minimize this temptation.
Economic analysis carried out for the Lifetime Ewe Management package demonstrated that it was most profitable for farmers to join in CS 3 and lamb in CS 3 and not feed grain to gain condition. This recommendation was robust for the range of prices examined in 2011 and for a range of regions and a range of time of lambing. Prices have since increased to levels outside the range examined in the package, so the targets for CS during pregnancy may have changed.
To further inform farmers, consultants and the agribusiness sector of the importance of nutritional management of their ewe flock and to improve decision making around the commitment of funding for purchasing feed, this project has calculated the cost of increased ewe mortality.
Ewe mortality at lambing is closely correlated to ewe CS at lambing and ewes that have a poor recovery post-weaning in 2019 due to a shortage of feed will be at risk of elevated mortality at lambing in 2020 if CS slips during pregnancy.
The analysis was carried out using the MIDAS suite of wholefarm models. Two regional versions were used, and 2 times of lambing were evaluated in each region for the Merino-Merino flocks and just the earlier lambing for the flock mated to a terminal sire.
Three flock structures were evaluated for each region. Two were based on a self-replacing merino ewe flock mated to merino rams. The first, ‘bag lamb’, was selling wether lambs into the air freight market and the second, ‘export hogget’, was selling wether hoggets into the live export market. The third flock structure, ‘1st cross lamb’, was a merino ewe flock mated to a terminal sire with all progeny sold as finished lambs and ewe replacements bought in. The merino genotype evaluated in the analyses was a medium-fine merino, with reproduction based on the WA flock average.
The price scenario was based on output prices received in WA for the last 12 months with sensitivity analysis +/- 25% of the standard levels.
The results reinforce that the ewe is the powerhouse of the sheep enterprise and maintaining the productive base of the sheep flock in the current market conditions is highly profitable. Increased ewe mortality in the average WA flock reduces profitability by an average of $280 for M-M and $320 for M-TS per ewe lost. These results are based on current prices and the expectation that extra losses are likely to occur from the twin bearing ewes because these tend to be lower CS at lambing (unless scanned and differentially fed in late pregnancy). For the M-M ewes there is little difference in the value associated with variation in flock structure. In the flock selling ‘bag lamb’ an average ewe is $5/hd more valuable and a twin ewe is $8/hd more valuable than in the ‘export hogget’ flock.
There is little variation in value of ewes lost between regions, time of lambing, flock structure or wool price. However, there is variation between dry, single and twin bearing ewes, and variation due to meat prices. Twin bearing ewes are $60/hd more valuable than single bearing ewes and varying meat price up or down by 25% changes ewe value by approximately $55/hd.
The cost of increasing ewe deaths is the equivalent of the benefit of increasing ewe survival and these values represent the amount that could be spent on a ewe to prevent mortality. However, in practice it is only possible to target interventions to an ‘at risk’ group and therefore the breakeven expenditure for the group of ewes is the ‘value per ewe’ multiplied by the expected reduction in mortality. If the intervention is extra feeding, then there will be associated increases in production and these need to be quantified when determining profitability of the intervention.
Calculations were carried out to examine feeding levels during pregnancy. Scenarios were examined for ewes with varying condition score at joining and compared losing, maintaining and gaining condition during pregnancy. In all scenarios examined it was more profitable to maintain condition than allow the ewes to lose condition during pregnancy. The value ranged from $5 per ewe for single bearing ewes in CS 3 at joining up to $22.60 for a twin bearing ewe in CS 2 at joining. For single bearing ewes in CS 3 this is an 83% return on funds invested in supplementary feed and for the twin bearing ewes in CS 2 it is a 375% return on the funds.
Gaining condition during pregnancy increased profit above that achieved from maintaining the ewes if single bearing ewes were in CS 2 or for twin bearing ewes in any condition score. For single bearing ewes in CS 2 gaining 0.5 CS increased profit by $1.70, which is a 10% return on the funds invested in the extra supplementary feed. Feeding the twin bearing ewes in CS 2 to gain weight increased profit by $10.70 per ewe which is a 60% return on funds invested.
These results give confidence to farmers and financiers that it is a profitable investment to feed all ewes to maintain condition during pregnancy and to feed single bearing ewes below CS 2.5 to achieve CS 2.5 and to feed twin bearing ewes to achieve a CS between 3 and 3.5.
Furthermore, there is also a non-financial benefit associated with reducing ewe mortality, associated with animal welfare and farmer stress levels. These factors have not been included in this analysis but are relevant non-financial goals for farmers and society.