A Sheep Profit Extension Programme

Good feeding management is the key to achieving optimum ewe condition score and high lamb growth rates.

Beef and Lamb NZ have started an issues based extension programme called “Farming for Profit”, and in Marlborough the most recent field day has been based around two issues: summer and autumn ewe management with the objective of producing as many lambs as possible at tailing; and improving post-weaning lamb growth rates.

Facilitator Greg Sheppard says that there are huge opportunities for farmers to improve profitability by attention to management detail in both these areas using the right tools and financial drivers.

“One of the issues in Marlborough is very dry summers, so ewes are often not in good enough condition at mating to achieve a high lambing result,” says Greg.

“Nationally the average growth rate of lambs is 80 – 100 grams per day, but we know that lambs can grow upwards of 300 g per day under the right conditions, so there is great potential for farmers to improve lamb performance.”

Summer and autumn ewe management

• Ensure sufficient body condition at mating, a score of 3.5 or better,

• Offer ewes a rising plane of nutrition from at least 10 days prior to tupping until the end of the first cycle

• Ewes in poor condition probably need drenching prior to mating but it is important to know what worms are present and any resistance issues and drench appropriately. Faecal egg counts are very useful.

• Understand the relationship between ewe body weight and body condition score – you could have a 70 kg ewe with a large frame with a condition score of only 2.5, whereas another ewe with body weight of 50 kg and a smaller frame and could have a body condition score of 3.5 or 4.0

• Draft out the top end of the ewe flock and put them on maintenance rations

• Understand the difference in maintenance feeding levels depending on the live weight of the ewe, for a 70 kg ewe the maintenance is about 1.1 kg of dry matter per day whereas for a 50 kg ewe it is about 1.0 kg per day

• Ewes that need to be fed preferentially should be on pasture that has a cover of at least 1200 kg DM/ha

• Toxoplasmosis and Campylobacter – vaccinate if present in the flock

• Don’t shear ewes within two weeks of mating or rams within six weeks of mating – the stress will adversely affect fertility.

• Assess ewe body condition at weaning and draft off the poor ones for preferential feeding that so that they achieve the body condition score target at the next mating

Improving the growth rate of lambs

• RAM selection — choosing the breeder not only on the basis of EVB for lamb weaning weight but also for the eight-month weight

• Decide what proportion of the flock you can afford to mate to a terminal sire – the lower the lambing % the lower the proportion.

• Weigh lambs at weaning

• Analyse the kill sheets from the works and sale dockets and dates to get understanding of what sort of growth rates have been achieved in the past. If you know the weaning weight and date and the works/sale weights you can calculate the average growth rate over that period to establish a benchmark. That will indicate the opportunity for improvement, eg. if the past average growth rate is 110g per day and you know that it is possible to get that up to 185g per day just on grass then there is the potential for an extra 75 g per day. Over 20 days that means 1.5 kg extra at $3.50 per kg over the whole lamb crop.

• Reduce stress factors as much as possible – make good decisions on shearing and yarding of stock for drenching, and the conditions under which these actions happen

• Drench when necessary taking into account the worms present and any drench resistance

• Understand the nutritive value of pastures and crops. In summer although the grass may look green and nutritious the quality drops markedly after day 14 because of increased lignin content, so having fast grazing rotations is important to maximising lamb growth rate.

• Ensure lambs don’t graze pasture below 1200 kg per hectare

• Clover content is crucial – dead clover has an ME of about 12 whereas dead grass has an ME of about 7

• The energy content of summer crops is far superior to summer pasture.

• Know what stocking rate your farm can support over the summer to achieve the results you are after. Too often farmers have more stock on than they can manage properly.

• Consider the financial dynamics of the season. They vary from year to year and what was profitable two years ago will not necessarily be the most profitable option right now. Assess the current market and seasonal climatic conditions then develop an appropriate strategy to maximise their returns eg. if lamb prices are high it may be cost effective to feed lambs supplements such as meal.

• Use long-term weather forecasts, price predictions, current sales and any other information you can get. There are many tools available for farmers.

• The faster the lamb grows more efficient feed conversion is and the more options you have or marketing that lamb in terms of sale date or weight.

Sheep farmer Richard Gorman has found that the key to success with both ewes and lambs is achieving high feed quality and quantity and feeding at the right time.

“I am very pleased with the lamb growth rates this year. We’ve had good feed right through from midwinter and pre-lambing to lambing and post lambing growth. It has been a cooler season than usual but our lambs have done well and we work hard at giving them better quality feed and keeping the ewes in good condition,” says Richard.

“Improved ewe condition has been the result of more attention to detail on feeding, growing more feed of high quality and ensuring that the sheep get it at the right time – quality and quantity of feed and grazing management. It’s the same for lamb growth.”

“Feed quality improvement amounts to grazing awareness, understanding what good quality feed is, achieving higher percentage of clover, and having forage crops to feed over winter so that the hill country can get away. That results in higher covers at lambing and allows the feed to stay ahead of the sheep. If you graze it too hard in winter, covers are too low and the stock will never perform.”

Richard grows annual ryegrasses and brassicas for winter feed, and has 40ha of lucerne for summer feed.