Options for Limited Forage Inventories

Posted: September 15, 2016

The hit and miss rain this past summer in Pennsylvania has left dairy producers with reduced forage inventories. Corn for silage within fields and farm is extremely variable in regards to plant height and corn grain fill. This will provide many challenges to the nutritionist in formulating rations that will remain consistent over time.

Production Perspective

The other challenge is extending the forage inventory until the next harvest window. The time is now to plan on how much forage is available and what alternative feeds would supplement the diet without breaking the bank.

Pennsylvania is fortunate to have a food industry where there is usually an ample supply of by-product feeds. There are other by-products that feed mills purchase on a routine basis that can also be used to extend forage inventories. The key is to match the right by-product with the forage ration. Checking the starch, fiber and their digestibilities in corn silage will be essential. Hay-crop forages may vary greatly from each cutting and affect the contribution of fiber and protein to the diet. There are several criteria to examine when selecting an alternative feed that best compliments the ration for the particular animal group.

Energy is the most limiting nutrient for the high producing lactating cow. If corn silage yielded well but starch levels are low (<30% on a dry matter basis), then feeds such as bakery waste (i.e. cookie or candy meal), liquid sugar, or other cereal grains might make a good fit. Supplementing additional starch alone does not always result in improved milk production. The better strategy is to diversify the carbohydrate profile with starch and sugars. Ingredients that provide some additional fat like chocolate or candy waste would help improve energy levels.

If total forage inventory is limited and added fiber is needed to balance the cows’ requirements, there are several options.  High fiber by-products include apple pomace, beet pulp, brewer’s grain, whole cottonseed, cottonseed hulls, and distiller’s grain to name a few. Each have their individual nutrient contents and recommended inclusion levels. Working with a nutritionist to evaluate what is the best option is highly recommended.

A costly mistake when evaluating feeding options is to make a decision based solely on the unit price ($/ton). The issue is only one side of the equation is being considered.  Evaluate a commodity’s potential by examining what it is contributing to the diet, how much is being fed, its cost per pound and the effect on milk income.  Penn State’s extension dairy business management team has been focused on income over feed cost for many years because it assesses how a ration change is impacting BOTH the milk income and feed expense. Other considerations include the consistency of the feed, palatability, ease of handling, and availability.

Implementing good feed management practices also helps fine-tune tight inventories. Maintain realistic refusals, keep feed pushed-up to cows, test dry matters weekly, monitor animal performance and follow standard operating procedures to help minimize feed wastage. The goal for 2016-2017 is keeping a tight rein on all aspects of the dairy operation.

Action plan for improving milk income.


Calculate forage inventory through May 2017 and September 2017 to determine rations that can be fed to all animal groups and where alternative feeds may fit.


  • Step 1: Meet with the dairy's nutritionist to calculate current forage inventories.   
  • Step 2: Have the nutritionist formulate rations for all animal groups and calculate monthly usage including the appropriate shrink from storage and feed out. Calculate the number of months feed will be available.
  • Step 3: Based on the inventory assessment, evaluate various alternative feed sources for the animal groups. Investigate the use of a by-product as a commodity and the possibility of locking in a price.    
  • Step 4: Evaluate the rations through the Penn State cash flow program to examine the impact on the operation's breakeven cost of production.   

Economic perspective

Monitoring must include an economic component to determine if a management strategy is working or not. For the lactating cows income over feed costs is a good way to check that feed costs are in line for the level of milk production. Starting with July's milk price, income over feed costs was calculated using average intake and production for the last six years from the Penn State dairy herd. The ration contained 63% forage consisting of corn silage, haylage and hay. The concentrate portion included corn grain, candy meal, sugar, canola meal, roasted soybeans, Optigen (Alltech product) and a mineral vitamin mix. All market prices were used.

Also included are the feed costs for dry cows, springing heifers, pregnant heifers and growing heifers. The rations reflect what has been fed to these animal groups at the Penn State dairy herd. All market prices were used.

Income over feed cost using standardized rations and production data from the Penn State dairy herd.

August 2016 IOFC
Note: August's PSU milk price: $17.31/cwt; feed cost/cow: $5.58; average milk production: 79 lbs.

Feed cost/non-lactating animal/day.

August 2016 Feed Costs

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Options for Limited Forage Inventories

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Contact Information

Virginia A. Ishler
  • Extension Dairy Specialist
Phone: 814-863-3912