There may be a soap opera going on in your barn. But this particular drama doesn’t involve people, it involves cows — the ones in group maternity or calving pens that see daily entry of cows into the pen.

Ken Nordlund likens the cow-to-cow social conflicts in this type of pen to the daytime drama that plays out on television. “There’s an entire world of soap operas that go on in barns every day,” says Nordlund, a veterinarian at the University of Wisconsin School of Veterinary Medicine.

Nordlund and colleagues Nigel Cook, Sheila McGuirk and Gary Oetzel have racked countless hours investigating and collecting on-farm data from group calving pens. What they found has convinced them that too much time in a daily-entry, group-calving pen derails fresh-cow health. Here’s why you should limit her stay to no more than two days.

Social disruption

“When we move cows, they have to reestablish rank,” Nordlund explains. In fact, cows need at least two to five days to acclimate to a new social environment. In pens that see daily entry of cows, this acclimation never really occurs, and that creates constant social turmoil, especially for subordinate cows.

The group calving pen — the “sea of straw” bedded pack so common on dairies — is a classic example of this. Extended stays in this type of pen “tend to be pretty hard on cows,” Nordlund says. And the effect of this stress is not limited to the pre-calving period; it extends into the cow’s next lactation.

Health disorders increase

The stress that results from constant social turmoil hurts subsequent cow health. Data from Nordlund’s own on-farm investigations show that when cows move into a group calving pen three to nine days before calving, it sets them up for health problems when they freshen.

“Our data suggest extended stays are almost always adversely related to health,” Nordlund says.

For example, on-farm data collected in 2003 by Oetzel show the rate of displaced abomasum doubled for cows that spent an average of seven days in a group calving pen.

You might speculate that those cows moved into the calving pen early because they were sick. “That simply wasn’t the case,” Nordlund says. There was no planned, early movement of “problem” cows into the calving pen.

That same on-farm investigation also showed plasma non-esterified fatty acid (NEFA) levels of the extended-stay cows exceeded the threshold of 0.4 milliequivalents (mEq) per liter. (Cows within two weeks to two days of calving should have NEFA levels less than 0.4 mEq per liter.) “This suggests to us that these cows are more at risk for fatty liver,” Nordlund adds.

And still more data show a negative effect of long maternity-pen stays on subsequent milk production and culling rate. (For more details, see “Short-stay advantages” on page 28.)

Not all pen moves are bad

Although a long stay in a group calving pen is bad, long stays in other pens may actually benefit cows. A good example of this is pens that see weekly entry of cows, such as the close-up or pre-fresh pen.

“The key difference is that daily entry pens create conditions of constant social turmoil,” Nordlund says. “Pens with infrequent additions of new cows have periods of social stability that make extended stays desirable.”

Nordlund points to a study published in the October 2001 Journal of Dairy Science. Although the focus of the study was not on pen stays, it shows a link between length of stay and future production. In particular, first-lactation cows that spent four days or less in the close-up pen produced significantly less milk in their subsequent lactation. Those animals produced anywhere from 2,845 to 4,920 pounds less milk over the course of their next lactation than cows that stayed five or more days in the close-up pen.

The bottom line: All pen stays are not created equal. However, the effect of a move into certain pens “appears to depend on the frequency of entry and departure from the pen,” Nordlund says. And in the case of a group calving pen, the consequences begin when the time between a cow’s entry and exit from the pen exceeds two days.

Pen Stays affect cow health

Extended stays in daily-entry calving pens: Bad for fresh-cow health.

Pre-fresh group pens that see daily entry of cows create constant social turmoil. Examples of these pens include group bedded-pack maternity pens or combined close-up/calving pens where new cows enter daily. Limit time spent in these pens to no more than two days.

Extended stays in stable calving pens: Good for fresh-cow health.

The “daily-entry” pen shown earlier has now been divided into three “all-in” pens that can create social stability. About 21 days before due date, move a group of close-up cows into one pen simultaneously. One week later, move the next group of close-up cows into the adjacent pen. That way, cows stay with the same group for the entire three weeks before calving.

Short-stay advantages

Cows that moved into a group maternity pen two days or less before calving produced more milk and were less likely to be culled by 60 days in milk than cows that spent more than two days in the pen.

 

Length of maternity pen stay

 

Outcome

 

Short 

(

 

Long

( 3+ days)

 

Advantage to

short stay

Number of calvings

 

112

 

182

 

 

Sold or dead by 60 DIM, %

 

3.6

 

9.3

 

2.6 X

 

ME milk at 1st test, lbs

 

20,777

 

20,205

 

+ 572 lbs

 


Extended stays in daily-entry calving pens: Bad for fresh-cow health.

Pre-fresh group pens that see daily entry of cows create constant social turmoil. Examples of these pens include group bedded-pack maternity pens or combined close-up/calving pens where new cows enter daily. Limit time spent in these pens to no more than two days.








Extended stays in stable calving pens: Good for fresh-cow health.

The "daily-entry" pen shown earlier has now been divided into three "all-in" pens that can create social stability. About 21 days before due date, move a group of close-up cows into one pen simultaneously. One week later, move the next group of close-up cows into the adjacent pen. That way, cows stay with the same group for the entire three weeks before calving.