Thin Cows? A Pre-breeding Nutritional Push Helps

By: Kris Ringwall, Beef Specialist

Spring was mellow this year. There was some cold weather, but more dry than wet
weather, which was good for calving. Calf losses should be minimal, while
keeping in mind that a 4 percent calf death rate is not abnormal. Even when the
weather is good, the calving season has some good and bad days.

Not all of the calves will survive, even with the most pristine management.
However, this is a good time to evaluate each calf loss and ask what else could
have been done. Be sure to make a note of it for next year. That being said, the
breeding season will soon be here, so next year’s calving note is not that
futuristic.

Are the cows ready? Attention needs to turn to the cows and ponder if they are
ready for breeding. Winter effects will vary, but for those cows that used up
some conditioning during the cold winter, spring feed is critical to meet
lactation needs, as well pending reproductive needs.

A quick review of typical winter impacts on cattle should start in November as
the calves and cows part ways. The cows quit lactating and generally will gain
some weight prior to winter. Most cows are in midgestation, so the demands of
pregnancy are minimal. Also, fall or crop aftermath grazing provides good
nutrition that lets the cows start the winter gaining weight.

The cows will do fine during November, December and January, and ideally will
gain 1.5 pounds per day. Typically, the cows will weigh in at 1,400 to 1,500
pounds, depending on the genetics involved in the cow herd, and we hope they
will have a body condition score of 5 or 6.

Even if the cows are smaller or larger, the key is the body condition score.
Regardless of size, the body condition score should be 5 or 6. In other words, a
producer should see some flesh on wintered cows. If these conditions are met,
then the cows were conditioned for calving.

Why the discussion of winter cow conditioning now? It’s because cows that are
fed well prior to calving will rebreed much better than those that are not.
Producers need to reflect back on winter feeding to assess potential problems
during the breeding season adequately.

A simple ration of 30 pounds of hay (adjusted to the size of the cow,
approximately 1.8 to 2.2 percent of body weight), which primarily is made of
good grass hay and approximately 20 percent alfalfa, would have been good last
winter.

The hope is that these same nutritional inputs during calving will maintain the
cows. However, once calved, cows need extra inputs. The change in the weight of
the cow and condition score post-calving is a function of the birth of the calf,
subsequent lactation or milk production, and environmental effects.

Associated calving weight loss easily could be 90-plus pounds of calf (average
birth weight) and, according to work done at Oklahoma State University, 20
pounds or more of uterus and placental membranes and almost 2 gallons of
placental fluid. Total calving weight loss alone could be 130 pounds or more.

Are these cows maintaining their actual weight and condition once calved? If
not, nutritional adjustments need to be made to assure adequate future breeding.
These adjustments should not be delayed because every day of lost weight means a
delayed onset of the breeding season.

Not untypical, what was once a herd of 1,400- to 1,500-pound cows is now a herd
of 1,200- to 1,300-pound cows that are looking a bit thinner. The loss of calf
weight and weight associated with birthing is not a nutritional concern, but the
loss of actual cow body weight is. If cows lose 50 to 80 pounds of actual body
weight following calving, in terms of total cow weight, the cows may have lost
almost 5 percent of their body weight. Various studies have indicated that one
body condition score is equal to 60 to 80 pounds of actual weight, thus the loss
of condition.

Now is the time for a managerial time-out. From a producer perspective, he or
she needs to review the current status of the cow herd and contemplate how to
get the cows to regain their lost weight. Following calving, increasing feed
amounts by 10 to 20 percent will help the cows maintain and regain body weight
prior to grass turnout and achieve a suitable body condition for breeding.

Cows that are losing weight or thin prior to breeding means delayed breeding and
open cows next year. Check with the herd nutritionist to make sure the current
nutritional protocol is meeting needs of your cows. Cows will lose weight if
they are milking more than predicted, the environment has been rougher than
thought or simply not enough feed is being fed.

Do not wait because poor conditioning impacts breeding.

May you find all your ear tags.