Animal Husbandry: Feed Conversion Ratio Explained

Feed conversion ratio (FCR) is a measure of how efficient an animal converts feed mass to desired output. The desired output may be eggs for laying birds, milk for dairy cows and goat, meat for meat animals such as broilers, pigs, rabbits etc, wool for animals like sheep, goats, rabbits etc. FCR is the mass of feed eaten divided by the output over a given period of time.

Farmers desire a low FCR because it means that more output is produced with less feed. Therefore a low FCR means lower feed cost. A FCR of 2 means that to produce 1kg output (live weight gain, milk), the animal will consume 2kg of feed.

Factors Affecting FCR

1. Genetics: Some animals have the natural ability to produce more output from less feed than other animals of the same species. For example, dairy goat breeds can produce much more milk than the non-dairy breeds. Commercial egg laying hens can produce far more eggs than the local breeds.
2. Age: Young animals grow faster than adult animals, so they have lower FCR. A farmer can use this knowledge to increase profit by selling or processing his animals before they reach adult age. This is common with broilers which are sold or processed in just 6 weeks. Some catfish farmers will raise their fish for 3-3.5 months and then sell or smoke them. This way, they benefit from the fast growth rate and less feed cost.
3. Feed Quality: Animals that are fed a diet that meet their nutritional requirement will have lower FCR. Nutritional requirement varies with the age of the animal in question. For broilers, there are chick starter and broiler finisher. For layers there are chick starter, grower and then layers mash. More complex feeding for layers can also include developer and pre-lay rations. All these feed were formulated to satisfy nutrient requirements at different stages of growth.
4. Management Method: This has to do with the welfare of the animals. Are the animals well protected from high temperature, cold, rain etc? Do you feed them well? Do you have measures in place to protect the animals from infection? Animals under cold weather will eat more feed to keep warm and this will lead to higher FCR than when the weather is fair. All these and more can affect the FCR.

FCR of Different Farm Animals

The values given below are general values. For specific values you may have to conduct further research.

1. Cattle: It rangers from 5-20.
2. Pigs: Ranges from 3-3.2.
3. Sheep: For lambs (4 months), FCR is 4-5 on high concentrate rations, 5-6 on good quality forage and more than 6 on low quality forage. On straw ration, it can be as high as 40. FCR for older sheep (8 months) is higher than those for lamb.
4. Poultry: Ranges from 1-2.
5. Crickets: About 1.7.
6. Fish: Tilapia has 1.6-1.8. Catfish is 1.5-5
7. Rabbits: 5-3 on high grain diet, 3.5-4 on forage without grain.

Conclusion

Feed conversion ratio (FCR) measures the feed intake per unit output (eggs, meat, milk). The lower the FCR the lesser the feed cost. Animals with low FCR are efficient in converting feed to output. If you want to reduce your cost of production, always think of ways you can reduce the FCR.

Do you raise chickens? Click here to find out how herbs and plant extracts can help decrease your FCR and improve the health of your chickens.