| | Recognizing and managing body condition of beef cows will add value to all cow/calf operations. Winter feed costs vary significantly, depending on body condition of cows in the fall, and fat cows will cost less to feed than thin cows. Depending on feed costs and cow size, one body condition score on a cow going into the winter season can mean an extra cost or savings of $35-60/cow.
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The research
From 1997 to 2000, Alberta Agriculture, the University of Alberta and industry conducted a winter-feeding trial to look at the effect of fall body condition on winter feed requirements of beef cows. In 1997/98, 196 pregnant beef cows were fed daily in pens of 4. In 1998/99, 50 pregnant beef cows were housed in individual pens and fed every second day. And in 1999/00, 60 pregnant beef cows were housed in individual pens and were fed every second day.
In the fall of each year, the cows were weighed, body condition scored (BCS) on the 5 point Canadian scale and then given ultra sound to assess backfat. The cows were then selected to receive one of three treatments:
- "thin" cows, BCS average of 2.3, were fed to gain condition,
- "moderate" cows, BCS average of 3, were fed to maintain condition, and
- "fat" cows, average BCS of 3.6, were fed to lose condition.
The feeding programs were set up to target a BCS at calving of 3 out of 5, which previous research established as the most productive BCS for a mature cow at calving. The trial lasted between 110 and 120 days each year, with the cows returning back to cooperating producers for the April calving season.
Results:
Table 1. Physical Changes in BW and BCS over the 3-year period
 | Thin | Moderate | Fat |
| Start BCS | 2.3 | 3.0 | 3.6 |
| End BCS | 3.0 | 3.1 | 3.3 |
| Change | +0.70 | +0.1 | -0.3 |
| Start weight, lbs | 1196 | 1289 | 1379 |
| End weight, lbs. | 1363 | 1403 | 1455 |
| Change (ADG), lbs | +167 (1.46) | +114 (1.00) | +76 (0.68) |
| Start backfat (mm) | 2.4 | 4.0 | 7.1 |
| End backfat (mm) | 6.1 | 4.9 | 7.0 |
| Change | +3.7 | +0.9 | -0.1 |
Table 2. Summary of rations fed over the 3-year period (lbs DM/head/day)
 | Year 1* | Year 2* | Year 3* |
Straw | Silage | Straw | Silage | Barley | Silage | Barley |
| Thin | 7.9 | 16.9 | 4.1 | 18.6 | 3.8 | 17.4 | 10.8 |
| Moderate | 7.7 | 16.0 | 7.8 | 17.9 | 1.8 | 19.8 | . |
| Fat | 6.8 | 13.9 | 8.3 | 15.1 | 0.0 | 18.4 | . |
*Year 1 - Barley silage and barley straw fed daily,
Year 2 -Alf/grass silage, barley straw and barley grain fed every second day,
Year 3 - barley silage, barley straw and barley grain fed every second day
Conclusions
The economic effects of this trial are shown in Table 3. Feed costs were calculated on a per-cow per-day basis and on per-1000 lbs of cow/day basis. This second calculation removes the variable of cow weight at the start of the trial, leaving body condition score as the only variable.
Costs are shown using two sets of feed prices. The 1997 to 2000 feed cost is calculated using actual average feed prices during the trial and may better reflect the economics of body condition management during an average year. The 2002 feed cost is calculated using average feed prices at the start of the 2002/03 feeding season, and these costs reflect the economics during a drought year.
Table 3. Feed Cost Summary Using 1997-2000 and 2002 Feed Prices
 | $/cow/day | $/1000 lbs of cow/day |
1997-2000 | 2002 | 1997-2000 | 2002 |
| Thin (2.3) | 1.15 | 2.06 | 0.96 | 1.72 |
| Moderate (3) | 0.88 | 1.70 | 0.68 | 1.32 |
| Fat (3.6) | 0.75 | 1.47 | 0.55 | 1.07 |
| Cost to feed thin over fat | $0.40 | $0.59 | $0.41 | $0.65 |
*1997-2000 feed prices: silage - $32/tonne as fed, straw - $32/tonne as fed, barley - $3.00/bus as fed.
2002 feed prices: silage - $60/tonne as fed, straw - $77/tonne as fed, barley - $4.00/bus as fed.
Industry often asks for a dollar value for body condition. Using the 2002 difference in feed cost/1000 lbs of cow/day between thin and fat cows of $0.65, body condition score difference of 1.3 at the start of the trial and a time frame of 115 days in the calculations, the value of one body condition score for the 2002/03 feeding season is $58. Using the 1997-2000 data, one BCS is worth $36. This $36 could be considered as a baseline for years when weather and feed prices are not as extreme.
This data also has implications for the amount of feed needed. Over the three years, thin cows required 26.5 lbs dry matter (DM)/day, whereas the fat cows only required 21 lbs DM/day, a difference of 5.5 lbs DM/day. Looking at Year 3 data only, where the difference in DM consumption was almost 10 lbs per cow per day, fall body condition can have very significant effect on feed and roughage needs.
Management
The above calculation suggests that one condition score can be valued at $58. This conclusion applies to 1000 pounds of cow and only for the duration of the trial, the first 115 days of the winter feeding season. The potential effect may be greater if the data were applied to the entire winter-feeding season and on larger cows.
The bottom line is that management of fall body condition of beef cows has economic value and can reduce roughage needs. For example, a producer with 150 cows could see returns from body condition management totaling over $25,000.
Management programs that increase fall body condition in beef cows include pasture management, early weaning and creep feeding. Other benefits from gains in body condition score are opportunities to go to skip a day feeding program, reduction or elimination of bedding needs, improved conception post-partum and improved colostrum levels at the start of calving. Either way you slice it managing body condition of beef cows will add value to all cow/calf operations.
Christoph E. Weder, Beef Specialist, AAFRD, Spirit River
and
Trevor Yurchak, Beef Specialist, AAFRD, Athabasca |
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