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Dairy cattle husbandry - Part 5

Appendix 1: Points to look for when buying an animal Age It is possible to guess the age of a cow by looking at its teeth. The milk incisors (cutting-teeth) are replaced by permanent incisors at fairly regular intervals, so you can estimate the age of a cow quite accurately until it is approximately 4 years old. | Appendix 1 Points to look for when buying an animal Age It is possible to guess the age of a cow by looking at its teeth. The milk incisors cutting-teeth are replaced by permanent incisors at fairly regular intervals so you can estimate the age of a cow quite accurately until it is approximately 4 years old. By this age it will have all its adult teeth. We stress that this gives only a rough indication however as different breeds change their teeth at different ages. As a guideline we include information on dental development for a Dutch milking cow see figure 16 the calf is born with 6 - 8 cutting-teeth incisors these are milk teeth 1 year and 3 months the cutting-teeth are hollow 1 year and 9 months the inner two teeth are replaced by two large teeth I1 2 years and 6 months the inner middle teeth are replaced I2 now four large teeth 3 years the next set of cutting teeth are replaced I3 3 years and 9 months the eye-teeth or canine-teeth I4 or C are replaced all the milk teeth have now been replaced. The cow now has four pairs of permanent incisors in the lower jaw. After this age we can only look at the wear of the chewing surface on the permanent incisors now. The ridges on top of the teeth which form a zig-zag line gradually become worn down until the surface is smooth. 5 years the cutting-teeth are beginning to show some wear beginning on the tongue side. 6 years the middle 2 incisors I1 have become flat 7 years the middle 4 incisors I1 and I2 are flat 8 years the middle 6 incisors I1 I2 I3 are flat 9 years all 8 incisors I1 I2 I3 and I4 are worn flat Appendix 1 Points to look for when buying an animal 71 Do not buy a cow that is older than 4-5 years for reproduction if you are not sure about her fertility. Appearance. Do not buy an animal with a disease. See for the checklist for general examination in Chapters 4 and 5. Figure 16 Teeth of cows at different ages Source Kroon 1922 . 72 Dairy cattle husbandry Appendix 2 How to handle cattle Animals react clearly