Daily Live Weight Gain (ADG) in beef cattle is the most basic indicator of performance. The ADG value reflects the combined effect of genetic potential, nutritional quality, health status and environmental conditions. In this article, ADG calculation methods, target values, affecting factors and its relationship with feed conversion ratio (FCR) are discussed in the light of current literature.
Economic Importance
Each 100 g/day increase in ADG can shorten the fattening period by 15-20 days and reduce feed costs by 8-12%. Optimal ADG is the key to profitable livestock management (Owens et al., 1995).
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Calculate ADG1. What is ADG and How is it Calculated?
ADG refers to the average daily live weight gain of the animal in a certain period. It is calculated with a simple formula, but accurate measurement and interpretation is critical.
ADG Calculation Formula
ADG (kg/day) = (Final Weight - Initial Weight) / Number of Days
Example: If an animal starting at 250 kg reaches 430 kg in 120 days:
ADG = (430 - 250) / 120 = 1.50 kg/day
1.1 Accurate Weighing Protocol
The reliability of ADG calculation depends on correct weighing technique. Intestinal fullness differences can affect weighing results by 3-8% (Lofgreen & Garrett, 1968).
- Weighing before feeding in the morning
- Same time for every weighing
- Minimum 12 hours of fasting (shrink)
- Calm, stress-free environment
- Calibrated scale
- Weighing average for 2 consecutive days
- Weighing after feeding
- Weighing at different times
- Weighing under stressful conditions
- Uncalibrated scale
- Single day weighing value
- Weighing during illness
2. Target ADG Values
2.1 Targets by Race and Gender
| Category | Target ADG (kg/day) | Acceptable Range | Description |
|---|---|---|---|
| Meat breed male (Angus, Hereford) | 1.4-1.6 | 1.2-1.8 | High genetic potential |
| Meat breed female | 1.2-1.4 | 1.0-1.5 | 10-15% lower than men |
| Combined breed male (Simental, Limousin) | 1.3-1.5 | 1.1-1.7 | Good muscle development |
| Dairy breed male (Holstein) | 1.1-1.3 | 0.9-1.4 | Longer fattening time |
| Native race (Native Black, Gray Steppe) | 0.8-1.0 | 0.6-1.1 | low genetic potential |
| Hybrid (F1) | 1.2-1.4 | 1.0-1.5 | Heterosis advantage |
Important Note
Very high ADG (>1.8 kg/day) is not always a desired situation. Extremely rapid growth, metabolic disorders (acidosis, liver abscess), skeletal problems and excess fat increase the risk (Owens et al., 1998).
2.2 ADG by Fattening Period
| Fattening Period | Live Weight (kg) | Expected ADG | Ration Features |
|---|---|---|---|
| Adaptation (0-21 days) | 200-250 | 0.8-1.0kg/day | High roughage, low concentrate |
| Growth (22-90 days) | 250-350 | 1.2-1.5 kg/day | Gradual increase in concentrate |
| Completion (90-150 days) | 350-500 | 1.4-1.7 kg/day | High energy finishing ration |
3. Feed Conversion Ratio (FCR)
3.1 What is FCR?
Feed Conversion Ratio (FCR) shows the amount of feed consumed for 1 kg of live weight gain. Lower FCR means more efficient feed utilization.
FCR Calculation Formula
FCR = Total Feed Intake (kg) / Total Live Weight Gain (kg)
Example: If 1080 kg of feed was consumed for 180 kg weight gain:
FCR = 1080 / 180 = 6.0 kg feed/kg live weight gain
3.2 Target FCR Values
| Category | Target FCR | Acceptable | Poor Performance |
|---|---|---|---|
| Intensive fattening (concentrate-based) | 5.5-6.5 | 6.5-7.5 | >8.0 |
| semi-intensive fattening | 6.5-7.5 | 7.5-8.5 | >9.0 |
| pasture based fattening | 8.0-10.0 | 10.0-12.0 | >12.0 |
3.3 Relationship between ADG and FCR
There is an inverse relationship between ADG and FCR. Higher ADG is generally associated with better (lower) FCR because the proportion of feed used for production increases while the living fraction feed requirement remains constant (NRC, 2016).
1.5
kg/day ADG
FCR: 5.8
excellent performance1.2
kg/day ADG
FCR: 6.8
Medium performance0.9
kg/day ADG
FCR: 8.5
low performance4. Factors Affecting ADG
4.1 Genetic Factors
The heritability (h²) of ADG is between 0.30-0.45, meaning that 30-45% of ADG is determined by genetic factors (Koots et al., 1994).
- Race: Meat breeds > Dairy breeds
- Gender: Male > Female (10-15%)
- Heterosis: 5-10% advantage in hybrids
- Individual variation: 20-30% within the same race
- Energy density: The most critical factor
- Protein quality: Importance of bypass protein
- Rough/concentrate ratio: optimal balance
- Feed quality: digestibility
4.2 Environmental and Management Factors
| factor | Optimal Condition | Effect on ADG |
|---|---|---|
| temperature | 5-20°C (thermoneutral) | Heat stress: -15-25% |
| shelter area | 6-8 m²/head (closed) | Insufficient space: -5-10% |
| feed area | 60-75cm/head | Insufficient: -10-15% |
| group size | 10-20 heads/lot | Large groups: -5-8% |
| health status | disease free | Respiratory disease: -20-40% |
5. Compensatory Growth
Compensatory growth is when animals that were undernourished for a period grow faster than normal when they switch to adequate nutrition. This phenomenon can be used strategically in livestock planning (Ryan, 1990).
Compensatory Growth Advantages
- Feed efficiency: During the compensation period, FCR improves by 10-20%
- Carcass quality: Less fat, more muscle
- Cost: Roughage in the cheap period, concentrate in the expensive period
- Limitation: Severe restraint can cause permanent damage
6. ADG Monitoring and Evaluation
6.1 Tracking Protocol
- Input weighing: At the beginning of fattening (shrunk weight)
- Intermediate weighings: Every 28-30 days
- Output weighing: Before cutting (shrunk weight)
- Feed consumption: Daily or weekly recording
- Health records: Illness, treatment, death
6.2 Checklist in Case of Low ADG
If ADG is Below Target, Check:
- Is the diet energy density sufficient?
- Is the feed quality (mold, spoilage) good?
- Is the feed area sufficient?
- Is water access and quality appropriate?
- Is there subclinical disease?
- Has the parasite load been checked?
- Is there heat stress?
- Is there social stress (hierarchy)?
7. Economic Evaluation
ADG is one of the most important determinants of livestock profitability. High ADG reduces fixed costs by shortening fattening time and increases capital turnover.
Livestock Break-Even Analysis
Perform profitability analysis with your ADG and FCR values:
Breakeven Calculator8. Resources
- Koots, K. R., et al. (1994). Genetic parameters for growth traits of beef cattle. Canadian Journal of Animal Science, 74(2), 293-302.
- Lofgreen, G. P., & Garrett, W. N. (1968). A system for expressing net energy requirements and feed values for growing and finishing beef cattle. Journal of Animal Science, 27(3), 793-806.
- NRC. (2016). Nutrient Requirements of Beef Cattle (8th ed.). National Academies Press.
- Owens, F. N., et al. (1995). Review of some aspects of growth and development of feedlot cattle. Journal of Animal Science, 73(10), 3152-3172.
- Owens, F. N., et al. (1998). Acidosis in cattle: A review. Journal of Animal Science, 76(1), 275-286.
- Ryan, W. J. (1990). Compensatory growth in cattle and sheep. Nutrition Abstracts and Reviews, 60(9), 653-664.