However, aggressive feeding behavior, better termed intensive feeding behavior, is another issue. It's a trait to encourage in your cows. As you well know, the best-balanced ration is for naught if cows don't eat enough of it.

”Keeping cow feed intakes at maximum levels is a common problem for dairies, regardless of size," asserts Rick Grant, University of Nebraska nutrition specialist.

"We need to put cows in an environment that will allow them to fulfill their biological potential. A good feeding-management system promotes intense feeding behavior while ensuring cow comfort, non-disrupted feeding activity and normal social behavior."

To do that, you have to look at a number of herd factors, including adequate bunk space, cow groupings, feeding area design, social dominance and feeding competition.

”Cattle develop a social structure and there are varying degrees of dominance among cattle," Montana State University Associate Professor of Ranch Science Bok Sowell told attendees of the American Society of Animal Science National Meeting last summer. "We know that the social structure of cattle is pretty stable until there's a change."

Yet, dairies are all about change. Cows cycle through the barn at least twice per day for milking and they must contend with periodic activity-interrupters like herd health checks and manure management. And cows are grouped and regrouped socially according to age, lactation or production levels to fit human wishes.

Research shows, and you know from experience, there are several highly competitive times at the feed bunk -- when fresh feed is offered and when cows return from milking. "The maximum effect lasts for about 30 to 35 minutes after these activities," notes Grant. "In the case of cows returning from milking, have fresh feed available if at all possible. It's a tremendous opportunity to maximize feeding."

On-farm research in western New York indicates a spike in feeding activity occurs whenever feed is pushed up in front of cows, when fresh feed becomes available or after milking as cows are on their way back to freestalls.

The key is having plenty of feed available with ample bunk space. Whenever feed availability is limited, competition escalates and submissive cows suffer. 

"A review of all published research indicates that when bunk space is less than 8 inches per cow, it reduces eating time and dry matter intake," reveals Grant. "Bunk space between 8 and 20 inches per cow increases competition with variable effects on intake, and bunk space greater than 20 to 24 inches per cow has no measurable effect on intake."

Group Dynamics
After studying groups of cows from 50 to 200 cows per group, Grant says there are no noticeable problems with cow behavior in larger groups per se. "However, management decisions play more critical roles in larger groups," he observes. "Irregular feeding intervals, overcrowding, excessive walking required to and from the parlor or insufficient bunk space can become impediments to feeding behaviors."

Furthermore, grouping older cows with younger cows can contribute to faulty feed-intake levels. "When heifers were separated from older cows, eating time increased by 11.4%, meals per day increased by 8.5%, silage dry matter intake increased by 11.8%, lying time rose 8.8% and lying periods increased by 19%," reports Grant. "The extra time needed by younger cows to chew and process feed is an important consideration in your feeding strategy."

 Design Time
On-farm Nebraska observations revealed farms with the highest dry matter intake had alleys wide enough for two cows to comfortably walk in opposite directions behind the row of cows standing and eating at the feed line. "In those facilities with insufficient space, either because of poor barn design or overcrowding, normal movement of cows in the alley behind the feed manger disrupted eating activity, precipitated fights and interfered with intense, focused feed activity," says Grant.

He suggests the alley between the feeding and the first row of freestalls should be at least 14 feet wide to allow comfortable cow movement. Crossover alleys containing water tanks should also allow for easy cow passage without interfering with cows that are drinking.

Finally, be sure feed barriers or mangers provide free access to feed without risk of cow injury or discomfort. Studies conducted last year evaluated the effect of cow pressure exerted on self-locking feeders and the resulting effect on feeding activity and cow comfort.

Results indicate pressures less than 112 pounds have no effect on the cow, pressures of 112 to 225 pounds may have some effect and pressures exceeding 225 pounds may cause acute tissue damage. These measurements were taken as cows received feed and the ensuing reaching required to obtain feed beyond the cows' immediate eating area. Pressure built as cows tried to eat feed at the outer limits of their reach. "More importantly," stresses Grant, "cows gave up trying to reach feed after about 14 minutes."

The effect was more pronounced as manger width increased and feed could be pushed beyond cow reach.

"Feed accessibility may be the most important factor affecting you cow's ability to maximize feed intake," concludes Grant.