Sunday, July 3, 2022

Ewe management enhances lamb survival

Simon Beamish and Farm Manager Shane Tilson still see a huge opportunity in improving lamb survival to sale on the Beamish properties.

Scanning is typically 195% to 200%, with survival to sale between 145% and 150%. They calculate lamb wastage by dividing the difference between their weaning and scanning percentages by the scanning percentage and multiplying that result by 100 (e.g. 200 – 150 = 50; 50 ÷ 200 = 0.25; 0.25 x 100 = 25%).

Their target for lamb wastage is 15%, but it has been as high as 25%. Simon and Shane are convinced the answer to weaning more live lambs lies in more intensive management of pregnant ewes and getting things right feeding-wise early in lactation. They accept that many natural hazards such as creeks and swampy areas exist throughout Awapai and Waitata, but still think 15% is realistic.

“One of our key strategies is more intensive condition management of ewes,” Shane says. “We have to get feeding and management right throughout the winter, but particularly during the last trimester of pregnancy and through to peak lactation. One of our biggest opportunities is in reducing the number of tail-end ewes as this is where huge losses can occur.”

Lighter ewes are assigned to the different mobs and managed differently in terms of mob size, feeding levels, the pasture species they graze, and the areas of the farm they are run on.

“If you have ewes in their different mobs all the time you have the ability to control where they are going and what they are doing.

“We recycle ewes back to another mob when they pick up, so the composition of the mobs is changing all the time.”

Shane believes that fluctuations in condition score from 2.5-3.0 result from management or feeding issues whereas a drop below 2.5 is an “individual sheep issue”.

“Individual ewes obviously lose weight for a number of reasons. Competition within the mob, teeth, internal parasites and sub-clinical animal health problems can all have an effect. If a group of ewes are light we may drench them, but only after we’ve analysed individual faecal egg counts and made a decision in conjunction with our animal health plan.”

The other big sheep management focus on Awapai has been the amount and quality of feed offered to all ewes in the last six weeks of pregnancy and the first two weeks of lactation.

“The higher the fecundity the greater the number of multiple lambs, including triplets, so the flock birthweight is lower and the newborn lambs more vulnerable. The amount and the quality of feed offered from late July to early September are critical, and pasture quality at this time goes back to cattle numbers and feed quality in the autumn.

“Ewes need plenty of high-energy, leafy feed in late pregnancy and early lactation. Our grazing residuals during this period are no lower than 1300kg DM/ha and we set-stock three weeks before lambing so that all ewes are fully fed. While we haven’t got it exactly right yet, we’re getting there.”

The Awapai team typically operate three mobs of commercial ewes, the “A, B and C” mobs, based purely on body condition score. Ewes are condition scored at least five times a year – a month before mating; when the rams are removed; before lambing; at docking; at weaning – and any other convenient time the sheep come through the yards.

Shane is adamant that condition scoring must be done properly. Both condition score and liveweights across the mobs are recorded and this data is presented at monthly meetings. The information now goes back six years and makes interesting reading.

“We condition score up the race, in there with the ewes,” Shane says. “It’s a hands-on procedure, not something that can be done properly on the drafting gate.”

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