To determine the feed conversion ratio (FCR) for the sheep, we need to follow a systematic approach. The FCR is a measure of the efficiency with which animals convert feed into body mass. It is calculated using the formula:
[ \text{Feed Conversion Ratio (FCR)} = \frac{\text{Total Feed Consumed (kg)}}{\text{Weight Gain (kg)}} ]
Step-by-Step Calculation
- Determine the Weight Gain:
- Initial weight of the sheep = 25 kg
- Final weight of the sheep = 45 kg
-
Weight gain = Final weight - Initial weight
[
\text{Weight Gain} = 45 \, \text{kg} - 25 \, \text{kg} = 20 \, \text{kg}
]
-
Total Feed Consumed:
-
The total feed consumed during the period is given as 60 kg.
-
Calculate the Feed Conversion Ratio:
- Now, we can substitute the values into the FCR formula:
[
\text{FCR} = \frac{\text{Total Feed Consumed}}{\text{Weight Gain}} = \frac{60 \, \text{kg}}{20 \, \text{kg}} = 3
]
- This means the FCR is 3:1, which can be expressed as 3:1.
Conclusion
The correct answer is
C. 3 : 1.
Explanation of Other Options
-
Option A: 1 : 1: This would imply that for every 1 kg of feed consumed, the sheep gained 1 kg of weight. This is incorrect because the sheep gained 20 kg while consuming 60 kg of feed, indicating a much less efficient conversion.
-
Option B: 1 : 2: This suggests that for every 2 kg of feed, the sheep gained 1 kg of weight. This is also incorrect as it would imply a total weight gain of only 30 kg if 60 kg of feed were consumed, which does not match the actual weight gain of 20 kg.
-
Option D: 4 : 1: This would mean that for every 4 kg of feed, the sheep gained 1 kg of weight. This is incorrect as it would imply a total weight gain of only 15 kg if 60 kg of feed were consumed, which again does not match the actual weight gain of 20 kg.
Summary
- The feed conversion ratio (FCR) measures the efficiency of feed conversion into body mass.
- The weight gain of the sheep was calculated as 20 kg.
- The total feed consumed was 60 kg.
- The FCR was calculated as 3:1, indicating that 3 kg of feed was required for every 1 kg of weight gain.
Revision Points
- FCR is calculated using the formula: ( \text{FCR} = \frac{\text{Total Feed Consumed}}{\text{Weight Gain}} ).
- Always ensure to calculate the weight gain accurately by subtracting the initial weight from the final weight.
- Understand that a lower FCR indicates better feed efficiency, while a higher FCR indicates poorer efficiency.
- Review the definitions and implications of different FCR values to better understand animal nutrition and growth efficiency.