14 Nov When the Rain Comes
Many parts of Australia are experiencing or have just experienced what is being called a ‘once in a generation drought’ and Graziers are waiting with bated breath for drought breaking rain.
After extended periods of drought it is great to have moisture in the air and to hear, smell and see the rain, showers and storms. However, there is a significant risk to stock during the immediate period following enough rain to generate a short green pick. This ‘green’ drought can often be harder on your stock than the actual ‘dry’ drought.
One of the main issues that arises after the first rain event is that any green feed that starts to shoot will prove a real temptation for cattle and sheep and they will often end up chasing the green pick. Some of the worst stock losses can occur in this situation due to livestock that already have depleted energy reserves using up a lot of their energy chasing the new growth that they won’t be able to eat enough of to meet their energy requirements. It is important that feeding livestock over the weeks following a break in the drought be carefully planned and supervised to avoid stock losses.
Be prepared for several weeks to go by after useful rain is received before there is sufficient pasture available to meet livestock nutrient requirements. This is due to the high moisture and lack of fibre in the green shoot and stock won’t be able to consume enough feed to meet their daily dry matter requirements. In addition, lush green fodder can pass too quickly through the rumen causing scours and reducing the absorption of important nutrients. During these first few weeks you might find that stock will stop eating supplements to chase green grass and to avoid this issue confining animals to holding paddocks and continuing to supplementary feed with roughage and protein supplement is the best option until there is adequate paddock feed available.
Livestock should be carefully transitioned onto lush green fodder and should never be introduced for the first time when hungry. Instead, ensure that stock have been provided a source of fibre such as hay, straw, whole cottonseed or any available roughage before introducing to green feed. Fresh, green grass is significantly high in sugars and has the potential to cause an ‘acidosis’ type situation that results in a decrease in rumen pH, similar to what can occur when ruminants consume grain without adequate fibre.
Rapidly growing, lush green pasture and forage crops can have excessive amounts of some nutrients such as potassium for example and can be very limiting in others like magnesium. Livestock that are grazing these plants in their vegetative growth stages can be prone to developing conditions such as scours, bloat and grass tetany, issues that can once again lead to stock deaths.
Once you have safely transitioned your livestock onto sufficient green pasture don’t forget that there is still a need to balance existing mineral deficiencies and supplementation should focus on the most limiting nutrient. During times when there is adequate energy and protein being supplied in green pasture, mineral supplementation will become a priority via the delivery of a low dose broad spectrum mineral supplement. If you know your country is deficient in phosphorus, then times of green feed is the best to concentrate on phosphorus. If you are going to have stock grazing forage sorghum or ticks and fly are a constant issue, then supplementing with extra sulphur may be of benefit. Magnesium is also a key mineral for areas where stock are grazing improved pastures, ryegrass and other cereals to help prevent grass tetany.
Lush green feed is an important, cheap resource for farmers and if managed correctly some significant production results can be achieved. The early introduction of a quality supplements such as MegaMin Mineral Blend, MegaMin Extra Phos 8, MegaMin Extra Sulphur and MegaMin Extra Magnesium and providing animals with effective fibre and allowing rumen microbes time to adjust to feed changes can help animals to become much healthier and more productive from the onset of grazing lush green feed.
AgSolutions’ Field Advisors can be contacted by calling 1800 81 57 57 and are always willing to help you with any livestock supplementation enquiries and advise on how to choose the right product for the right time.