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A comparison of the USDA ossification-based maturity system to a system based on dentition
T E Lawrence1, J D Whatley, T H Montgomery
1Division of Agriculture, West Texas A&M University, Canyon 79016-0001, USA.
Journal of Animal Science
|July 24, 2001
Summary
Comparing USDA bone ossification and incisor count for cattle maturity, this study found no statistical link. Incisor count may offer a more accurate method for sorting beef carcasses into consistent age groups.
Area of Science:
- Animal Science
- Meat Science
- Agricultural Science
Background:
- Cattle maturity assessment is crucial for meat quality and grading.
- Current USDA system relies on subjective evaluation of skeletal and lean maturity.
- Alternative methods, like dentition-based assessment, warrant investigation for improved accuracy.
Purpose of the Study:
- To evaluate the relationship between the USDA bone ossification-based maturity system and a system based on the number of permanent incisors in cattle.
- To determine the accuracy of each system in classifying cattle age at slaughter.
- To identify potential biases in the current USDA maturity classification.
Main Methods:
- Two studies involving commercially fed cattle were conducted.
- Cattle maturity was assessed using both USDA bone ossification criteria and the number of permanent incisors.
- Statistical analysis, including Kappa tests, was used to compare the two systems.
Main Results:
- No statistical relationship was found between the dentition- and skeletal ossification-based maturity systems.
- Dentition-based maturity agreed with ossification/lean maturity for a low percentage of carcasses (12.8% in Exp. 1, 27% in Exp. 2).
- Cattle with multiple permanent incisors were often misclassified into younger age categories by the USDA system, with males being more prone to misclassification.
Conclusions:
- The number of permanent incisors appears to be a more objective and potentially accurate method for determining physiological maturity in cattle compared to the current USDA system.
- The USDA bone ossification/lean maturity system may misclassify cattle into younger age groups, particularly those with more permanent incisors.
- Utilizing incisor count could lead to more consistent sorting of beef carcasses into less variable age groups, improving grading accuracy.
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