Finishing Lambs in an Extremely Wet Spring

Recent reports from MLA and Auctions Plus have indicated that the current crop of new season lambs is running well behind previous years, with throughput in early spring back significantly on the same period over the past five years. As producers look to take advantage of the premiums on offer for well finished new season lambs, it is important to discuss what is driving the delay and what producers can do to get their lambs up to weight and into the market as soon as possible.

Anecdotal evidence from cattle and sheep producers across large swathes of NSW and Victoria suggests that liveweight gain over winter and early spring has been well below expectations. In some cases, despite the abundance of green feed available, there are reports of livestock even going backwards during winter. “There’s just no guts in the pasture this year”.

While there are several variables that may be affecting the growth of livestock throughout winter and spring, environmental and internal parasite burdens tend to get a lot of attention, and rightly so, however, assuming we have addressed these effectively, one factor that is often overlooked yet can be easily corrected and have just as much if not more of an impact on production, is nutrition.
To effectively correct production limiting nutritional deficiencies, it is important to understand where livestock are lacking in nutrition, even when feed is green and growing, and what actions to take in order to efficiently improve liveweight gain.

At first sight, results of plant tissue analysis from a range of pastures throughout NSW and Victoria are consistent with expectations of mineral, energy and protein levels (on a dry matter basis), in actively growing early spring pastures. This is usually more than adequate to support rapid lamb growth, however, also consistent in the samples tested were moisture levels of between 85 and 90%. In simple terms, animal nutrition is calculated on a moisture free basis known as “dry matter”, as all the nutrients important for animal production (mineral, energy, protein and vitamins) are located in the dry matter fraction of feeds. As intracellular moisture (water in the plant cells) of feed exceeds 85%, the elevated water content causes animals to feel full before they have consumed enough pasture to satisfy dietary requirements, i.e., they involuntarily reduce their “dry matter intake”, and in doing so, lower mineral, energy, protein and vitamin consumption. This effect increases exponentially as moisture levels of feed incrementally rise above 85%.

For example, in a normal season a 35kg lamb grazing rye grass (11.6MJ and 25% CP), may be able to consume 1.5kg of dry matter per day to achieve liveweight gain of around 280g/hd/day. By comparison, this year, due to the extremely wet conditions increasing the moisture content of pasture, the amount of dry matter consumed could be closer to 1.0kg/day and achieve an estimated liveweight gain of around 120g/hd/day. This is well below the growth rate we would associate with lambs grazing high quality rye grass.

To satisfy energy requirements, it is recommended to supplementary feed growing lambs with a high energy form of grain, like barley, at around 200g/hd/day. This will boost the energy level in the diet while still allowing the livestock to rely heavily on grazing. To balance the diet and achieve best results, it is recommended to pair the grain with a green feed mineral supplement like StockMins-Lamb Finisher.

StockMins-Lamb Finisher is a weatherproof, granular supplement designed to elevate the essential mineral, vitamin and trace element status of grazing livestock. It promotes greater feed conversion efficiency, energy metabolism and immune function to generate rapid growth on mineral, energy and protein deficient pastures, particularly, when paired with grain. StockMins-Lamb Finisher contains a unique combination of magnesium from four different sources, elevating availability, absorption and essentially the magnesium status of supplemented animals.

StockMins-Lamb Finisher is built with Bovatec®, to further boost liveweight gain, and feed conversion efficiency in sheep. In fact, numerous studies have shown Bovatec® to generate up to 14% extra growth in livestock grazing green feed1.

Ask the ANP team about how you can turbo charge your lamb finishing operation and get your lambs up to weight and into the market sooner.
JON MEGGISON 0412 048 055

StockMins-Lamb Finisher Product Summary:

1. Zoetis Data on File. ®Bovatec is a registered trademark of Zoetis.