Age is an important part of livestock trading as many markets have age limits.
Age of beef cattle at slaughter is strongly related to tenderness and meat colour.
Counting the number of permanent incisor teeth is the most common method of determining
age in cattle.
(MSA grading uses bone ossification, which is assessed on the carcase in the meat works.
Obviously this method cannot be used on live animals.)
Cattle, like many animals, start life with baby or milk teeth. From about two years of age
these teeth are replaced with permanent teeth. Permanent teeth erupt in pairs starting with
the centre pair.
A tooth is considered to have ‘erupted’ when it has broken through the gum.
A pair is considered to have ‘erupted’ when the first tooth of a given pair has broken through the gum.
Figure 1. This is a 6 tooth animal. There are four obvious permanent teeth and two more either side
breaking the gum. Note that you count the permanent teeth on the lower jaw. The upper jaw has no teeth
– only a dental pad.
The age of an animal is often referred to by the number of permanent teeth. An animal with only milk
teeth is
called a ‘milk tooth’, an animal with 2 permanent teeth is a ‘2 tooth’ and so on until they have a full set
of 8 permanent teeth when they are said to be an ‘8 tooth’ or ‘full mouth’.
The range in age at teeth eruption is enormous. It varies from beast to beast due to individuality,
breed, nutrition and climatic influences. Cattle that exhibit early sexual maturity (puberty) have teeth
eruption at younger ages than late maturing cattle. British-bred cattle have tooth eruption at younger
ages than Brahman cross cattle.
Table 1. A guide for estimating the age (in months) of cattle by dentition
Teeth | Breed | Average age (months) at eruption | Range in age at eruption (months) |
---|---|---|---|
2 tooth | British cattle Brahman cross | 24 26 | 21-27 23-29 |
4 tooth | British cattle Brahman cross | 31 33 | 26-36 28-38 |
6 tooth | British cattle Brahman cross | 38 41 | 32-44 35-47 |
8 tooth | British cattle Brahman cross | 46 51 | 39-54 43-58 |
From this table you can see that a beast with four permanent incisor teeth could be as young as 26 months
or as old as 38 months.
Despite this inaccuracy, dentition (or teeth counting) is still a useful way to assess cattle age.
Below are visual representations of cattle dentition, courtesy of AUS-MEAT Limited.
0 tooth
2 tooth
4 tooth
7 tooth
8 tooth
Article Credit:http://futurebeef.com.au
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