Sheep Ultrasound Pregnancy Diagnosis

Since 2002 the Department of Agriculture has been able to offer a Ewe Ultrasound Pregnancy Diagnosis (scanning) to farmers. Pictured right is Veterinary Officer, Zoe Luxton, pregnancy scanning sheep.

Worldwide, scanning is used as an important management tool. It allows producers to relatively accurately predict lambing percentage. These results are then used to alter or fine-tune management practises relating to nutrition, health and pasture use. This practise has therefore fitted neatly into the Farm Improvement Programme.

The scanning information can also be utilised as a financial forecasting tool: i.e. cash flow budgets, enabling better estimates of income and expenses.

The most basic way to use scanning as a management tool is to determine which ewes are pregnant and which ewes are not. This allows you to:

• Feed accordingly – while non-pregnant ewes should not be allowed to fall away completely (they will never get pregnant next season if they do), there is no point having a mob of mostly dry ewes on your swedes or re-seeds. Keeping the pregnant ewes in good condition  means they can feed and raise lambs successfully and be in good enough condition to then get pregnant again next year. Ewes in good condition have a better chance of keeping lambs alive and maximising growth rates.

• See what your conception rates are compared to lambs born or lambs marked. If your conception rate (number of ewes getting pregnant) is 70% for example but your lamb marking percentage is 50% - where are you losing that 20%? Are the ewes aborting the pregnancies? Are the lambs being born but dying before marking due to poor nutrition?

• See if any particular ewes are consistently not producing a lamb. These barren ewes should be culled.

A step further will be to identify and separate any ewes carrying multiple pregnancies. Ewes carrying twins need a bit more energy in the last stages of pregnancy and during lactation or they may suffer twin lamb disease – which can be fatal.

Having your ewes in while scanning is another good opportunity to body condition score them, ewes in poor condition could be separated and receive different nutrition.

The table below shows yearly fluctuations in the number of ewes scanned and number of farms utilising the service. Whilst the weather has had a significant part to play in these figures, ultimately it has been farmer choice. The 2009 figures show a pleasing increase in farms scanning their ewes.  

                      * Incomplete data

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Falkland Islands Government