What’s the trick for fresh green pick?

March 2020

Lou Baskind - District Veterinarian

“Green pick” is the name given to the very young, very short grass that is the first to emerge when the plant starts growing after rainfall. It is tempting when we see this beautiful bright green stuff to feel like we can relax a bit, sit back and watch the livestock grazing naturally like they are supposed to.

So what is the problem? Well, for one – it’s so short they can only grab a small bite in each mouthful. This means they have to graze long hours and long distances each day to get enough feed. This is what is referred to as “chasing the green pick”. This chasing comes at a high cost – the calories used in the walking and grazing activity can exceed the calories taken in. Secondly - green pick is very high in water content. So with each mouthful of it, the animal is taking in about 80% water and only about 20% nutrients like energy and protein. This means they cannot eat enough of it to meet their needs. The result of this is that animals can lose weight or “go backwards” quickly. For animals with high nutritional demands, such as young growing animals or reproductive females, this weight loss can be quite dramatic. This rapid movement of food through the gut can also allow a build-up of dangerous bacteria called clostridium, which can kill animals with a disease known as Pulpy Kidney.

This rapidly growing pasture is imbalanced in vitamins and minerals, and may also accumulate toxins and poisons, especially after a drought. It’s not only the grass that’s growing - the conditions have been perfect for the germination of other potentially toxic plants and weeds. And, if clovers are a strong part of the pasture mix, they can be responsible for causing bloat.

So how do we keep the stock in good health in these seemingly terrifying circumstances?

• Provide roughage. Unlike in a normal summer, we don’t have any mature taller plants which livestock can eat to get their roughage. Their only feed in the pasture is the short green pick. It is important they are provided with a source of roughage like a quality hay. Once you provide the hay you must monitor your stock. If they are not self-selecting a combination of roughage and green grass you will have to implement a more intensive approach. Yarding them overnight with hay and then letting them out later in the day after they have filled up on roughage, or use small paddocks or temporary fencing to force consumption of the roughage along with the green pick.
• Vaccinate for clostridial diseases. All ruminants on fresh green pick should have a booster of a 5-in-1 vaccine if they haven’t been vaccinated in the last 3 – 6 months.
• Provide minerals including sodium, calcium and magnesium. Magnesium is very important for breeding cows and ewes. These can be provided as dry licks or lick blocks for convenience, or the extra conscientious livestock manager can treat the hay or pasture with the magnesium. The DPI website has information on rates and methods of application.
• Monitor animals carefully. Keep an eye on body weight, any unusual behaviours such as agitation, or changes in gait such as stiffness or staggering. If you notice anything unusual, first quietly yard the animals and provide a low quality non-green hay. Then contact your vet or LLS District Vet for advice.

The period of highest risk is the first six weeks from the emergence of the green pick.