Extending Livestock Feed Supplies:
Feed Processing and Salt Supplemented Intake
1. Feed Processing
Grain Processing
Feed is often the largest cost in livestock production, making grain processing an important factor in feed efficiency and profitability.
- Processing Benefits: Rolling or grinding grain typically improves feed efficiency in cattle by 10–15% over feeding whole grain.
- Oats: Minimal benefit from processing.
- On-Farm Processing: Dry rolling and coarse grinding fracture kernels, increasing surface area for rumen microbes.
- Pelleting: Improves handling and mixing, and can increase feed efficiency by 5–10%, but the economic return often does not offset additional processing costs.
Forage Processing
Grinding roughage has value primarily when feed quality is low.
- High-quality forage: Little or no benefit from grinding.
- Low-quality roughage or straw: Grinding through a 1.3 cm (½ inch) or larger screen improves consumption, utilization, and rate of gain.
- Nutrient Balancing: Ground forages require appropriate protein, mineral, vitamin, and energy supplementation.
- Management Note: Finely chopped or ground hay increases risk of digestive disturbance and bloat. Ration changes must be gradual.
2. Regulating Grain Intake Using Salt
Self-feeding grain supplements on pasture is an effective method to extend feed supplies and ensure timid animals receive their share. Salt can be used to limit intake, though individual tolerance varies.
Factors Affecting Salt Intake
- Forage availability and palatability
- Salt content of water and forage
- Adaptation to salt
- Supplement palatability
As cattle adapt, salt content typically must be increased to maintain intake control. Cattle consume more salt-limited supplements when forage is scarce or poor quality. Adequate water is critical—cattle on salt mixes drink 50–75% more water, approximately 5 gallons additional per pound of salt.
Salt Toxicity
Salt toxicity is rare when water is available; lethal doses for mature cattle range from 1.8–2.3 kg (4–5 lb) of salt.
3. Using Salt Intake
Table 1. Estimated Salt Intake of Cattle Fed Salt‑Limited Supplements
Animal Weight |
Animal Weight |
Average Daily Salt Intake |
Average Daily Salt Intake |
Daily Salt Intake Range |
Daily Salt Intake Range |
kg |
lb |
grams |
lb |
grams |
lb |
136 |
300 |
227 |
0.5 |
136–272 |
0.3–0.6 |
227 |
500 |
272 |
0.6 |
227–318 |
0.5–0.7 |
318 |
700 |
318 |
0.7 |
272–409 |
0.6–0.9 |
409 |
900 |
409 |
0.9 |
318–500 |
0.7–1.1 |
500 |
1100 |
500 |
1.1 |
364–591 |
0.8–1.3 |
591 |
1300 |
591 |
1.3 |
409-682 |
0.9-1.5 |
Table 2. Daily Feed Consumption Expected with Various Salt Concentrations
Salt Intake / Day |
Feed Type |
Unit |
12% Salt |
16% Salt |
20% Salt |
30% Salt |
40% Salt |
227 g (0.5 lb) |
Total Feed |
kg |
1.9 |
1.4 |
1.1 |
0.7 |
0.5 |
lb |
4.2 |
3.1 |
2.5 |
1.7 |
1.2 | ||
Nonsalt Feed |
kg |
1.7 |
1.2 |
0.9 |
0.5 |
0.3 | |
lb |
3.7 |
2.6 |
2.0 |
1.2 |
0.7 | ||
272 g (0.6 lb) |
Total Feed |
kg |
2.3 |
1.7 |
1.4 |
0.9 |
0.7 |
lb |
5.0 |
3.8 |
3.0 |
2.0 |
1.5 | ||
Nonsalt Feed |
kg |
2.0 |
1.5 |
1.1 |
0.6 |
0.4 | |
lb |
4.4 |
3.2 |
2.4 |
1.4 |
0.9 | ||
318 g (0.7 lb) |
Total Feed |
kg |
2.6 |
2.0 |
1.6 |
1.1 |
0.8 |
lb |
5.8 |
4.4 |
3.5 |
2.3 |
1.7 | ||
Nonsalt Feed |
kg |
2.3 |
1.7 |
1.3 |
0.7 |
0.5 | |
lb |
5.1 |
3.7 |
2.8 |
1.6 |
1.1 | ||
409 g (0.9 lb) |
Total Feed |
kg |
3.4 |
2.5 |
2.1 |
1.4 |
1.0 |
lb |
7.5 |
5.6 |
4.5 |
3.0 |
2.2 | ||
Nonsalt Feed |
kg |
3.0 |
2.1 |
1.6 |
1.0 |
0.6 | |
lb |
6.6 |
4.7 |
3.6 |
2.1 |
1.3 | ||
500 g (1.1 lb) |
Total Feed |
kg |
4.2 |
3.1 |
2.5 |
1.7 |
1.2 |
How to Use the Tables
- Identify expected salt intake in Table 1 based on cattle weight.
- Locate that salt intake on the left column of Table 2.
- Read across to the non-salt feed row.
- Select the salt percentage that yields the desired grain intake.
Example
Goal: Feed 2.7 kg (6 lb) of grain per day to 500 kg (1100 lb) cows.
- Table 1: 500 kg cattle consume ~500 g (1.1 lb) salt/day on restricted supplements.
- Table 2: At 500 g salt intake, a 16% salt mixture yields ~2.7 kg (6 lb) non-salt feed.
Result: Feed a supplement containing 16% salt and 84% grain. Minor adjustments may be needed to fine‑tune intake.
4. Management Precautions for Salt‑Limited Supplements
- Provide plenty of clean water.
- Use coarse, plain white salt only—do not use trace mineralized salt due to toxicity risk at high intake.
- Grain should be coarsely ground or cracked and mixed with salt of similar particle size to prevent separation.
- Ensure adequate pasture or hay so cattle are not forced to overconsume supplement.
- For cattle unfamiliar with supplements:
- Start with a 50:50 or 60:40 salt-to-grain mix to prevent overeating.
- Gradually reduce salt to achieve desired intake.
- Young cattle may require a 1-week training period with daily hand‑fed, salt‑free supplement.
- Note: These intake values do not apply if Rumensin is used, as it independently limits consumption.