Dr. Hugh Chester-Jones
Animal Scientist, SROC

Neil Broadwater
Regional Extension Educator-Dairy
Neil Broadwater, Regional Extension Educator-Dairy

May 20, 2005

“Feeding management as a consistent process is not new. It was extolled in the Henry and Morrison Feeds and Feeding textbooks nearly 100 years ago. Technological advances have not diminished its importance.” Those words are quoted from a paper by Dr. Robbi Pritchard, Dept. of Animal and Range Sciences, South Dakota State University presented at the 9th National Dairy Calf and Heifer Conference in Sioux Falls, SD, in late March, which we both attended.

Bunk management seems so simple. Just deliver the planned amount of feed into the bunk that has been balanced for the dairy heifer group, stand back, and watch them eat and grow. However, most producers who raise heifers know it is more complicated than that. Bunk management can be greatly neglected by not paying attention to that final important step of feeding – the nutrient and energy intake by the dairy animal. Dr. Pritchard states that “the objective of good bunk management is to ensure that daily nutrient requirements are met, that over-consumption of rapidly fermentable carbohydrates by individuals is avoided, and that feed wastage is minimized.” Efforts need to be concentrated on the two most important keys to good bunk management: Improved Feed Efficiency and Reduced Daily Feed Costs.

Here are some important considerations for proper feed bunk management for dairy heifers:

• Feed delivered to the bunk must be uniform from one end of the bunk to the other or the dairy animals end up with an inconsistent diet. The consistency of delivering the proper quantity and quality of feed and at the proper times on a day to day basis is vital. Every dairy farm should have a standard operating procedure (SOP) on how the TMR is mixed and how the different heifer groups are fed. The goal of using an SOP for bunk management is to remove any variation, and to develop consistency and accuracy. Consistency can lead to significant performance improvement in raising dairy replacement heifers.
• It is important to take some time to watch all the animals as they eat. Are they all diving into the feed or are some backing away from it? Is there competition at the feed bunk?
• Check feed bunks before the next feeding. A shortage of feed at the bunk restricts dry matter intake which causes poor performance. Too much feed is a waste and costs money. What the heifer leaves at the bunk should be analyzed to determine if something in the ration or a feeding strategy needs to change. Taking samples of the feed refusal from different areas of the bunk and sending them to a forage testing laboratory can help compare nutrient profiles to the fresh bunk mixture.
• Adopt a system of scoring the feed bunk. Scoring bunks should be done the same time each day. Feed bunk scoring can help spot problems in forage dry matter, forage quality, or ration problems. Different bunk scoring systems can be used. Dr. Pritchard at SDSU uses a bunk scoring system with three categories and also uses codes. The system includes: ‘0’ – clean bunk; ‘½’ – small amount of feed scattered throughout the bunk; ‘1’ – sufficient carryover feed to completely cover the bottom of the bunk (< 1” deep). Codes used include an ‘R’ for coarse feed particles remain; an ‘F’ denotes the presence of fines; ‘WB’ means that out of condition feed must be removed from the bunk. An alternative bunk scoring system developed by Pat Hoffman (2003) at the University of Wisconsin is as follows:

• Make sure there is adequate bunk space to allow all heifers access to fresh feed and to be able to observe those that may be off feed. In 1999, Penn State researchers studied feed bunk length for heifers of varying sizes. They found that a reduction in feed bunk length significantly affected the feeding behavior of the heifers within a group.
• Proper feed bunk space allows heifers to be in a harmonious housing environment that allows them to achieve the body weight gains and skeletal growth necessary to achieve first calving-age goals of between 22 and 24 months of age.

• In a Michigan study, it was concluded that old feed should be removed at least once a day. Smooth surfaces are easier to clean, and avoid mold and odor formations.
• Consider how errors in nutrient delivery can occur and try to avoid them. There can be errors in the nutrient composition assigned to feed ingredients. There can be incorrect amounts of ingredients added to the TMR. There can be an error in the nutrient analysis of feed ingredients resulting from poor sampling technique on the farm, infrequent feed sampling and testing, or inaccurate laboratory analysis. Scale error can occur and the calibration of scales should be done routinely. Undermixing or overmixing can cause incorrect ration delivery.

In conclusion, managing the feeding process on a consistent basis on the farm is not new. Even with today’s technologies, it involves attention to detail, everyday. With good bunk management, feed efficiency is improved, there is the assurance of meeting the nutrient needs of the dairy animals being fed, feed wastage is kept to a minimum, and feed costs are under greater control.