Leafy, The Right Choice for Silage Production
Our Schlessman RFS leafy hybrids have been selected for their superior performance. Yield is high. Stress tolerance is high. Fiber is more
digestible than grain hybrids. Kernels are less vitreous, more floury than dual purpose or BMR hybrids and the starch content of leafies is more digestible.
The range in NDFd at 24 hours in dual purpose hybrids is 40 – 48% and with leafies that range is 48 – 56%. Starch digestion at 7 hour values with dual purpose varieties have been measured at 45 – 55%, while leafies results are 60 – 75% digestible starch.
The total package of digestible fiber and starch combined with high yield makes leafy the best product for digestible carbohydrates that produce milk on a per acre basis.
Leafies have 2 or more additional leaves above the ear than nonleafies. As the ear height of leafy varieties is lower, the amount of less digestible stalk below the ear versus more digestible stalk above the ear, is dramatically different from normal leaf number high ear hybrid. Sugar content in leafies at silage harvest stage is high, leading to rapid fermentation. Leafies have been selected to have lower test weight kernels that mature slowly relative to the maturing and drying of the non-ear parts.
This leads to best kernel digestion, easier kernel breakage in processing and preservation of longer pieces of fiber for rumen mat fermentation. Slower ear drying also leads to a longer period of time that leafies stay in the target harvest moisture range – incredible insurance value for getting in the silo in difficult weather times.
Time to hold silage in the silo before you feed is a serious consideration. The dual purpose and BMR hybrids all recommend a minimum of 4 to 6 month storage before feeding because of their very vitreous kernels. Longer storage means fermentation acids act on kernel components to increase starch availability. With the softer kernel texture of leafy hybrids, starch availability or digestibility is already high after one month fermentation. It does improve with time in the silo. But starch is so digestible that many growers, who have switched to leafy, say milk production goes up when they switch from year old dual purpose silage to new crop leafy after only 2 to 4 weeks in the silo.
The leafy silage product is fresh smelling, the fiber content and its digestibility mean the cow eats a lot. The fiber structure promotes adequate cud chewing to buffer rumen acids and seems to retain smaller particles in the rumen to be digested by rumen bugs into digestion products that the cow makes milk from.
When selecting lines for silage, some of the traits we are looking for include being dependable, high yielding, having a relatively long period during which quality silage can be harvested, producing food which produces milk and helping to maintain cow health in high corn silage rations. Additionally, these lines must have excellent stalk flexibility, high grain content, controlled leafy characteristics, high starch digestibility and good fiber digestibility.
Much of the focus on dairy feeding research has been on forage as it relates to intakes, digestion, milk production, reproduction and health of dairy cows. Corn silage is made up of fiber and kernels. Kernels are made of predominantly starch, some oil, protein and fiber. The digestibility of starch is not considered as a variable quantity in any of the dairy formulas currently in use. Yet farmers, nutritionists and veterinarians all know that cows don’t digest all of the starch in corn silage. Some kernel pieces are seen in the cows’ manure.
In summing things up, grain breeding ideas are largely opposite of what a corn variety should be for corn silage production to make the best milk