Presentation is loading. Please wait.

Presentation is loading. Please wait.

Determining Age of Animals. Introduction The only accurate method of determining the age of an animal is to know its birth date. The only accurate method.

Similar presentations


Presentation on theme: "Determining Age of Animals. Introduction The only accurate method of determining the age of an animal is to know its birth date. The only accurate method."— Presentation transcript:

1 Determining Age of Animals

2 Introduction The only accurate method of determining the age of an animal is to know its birth date. The only accurate method of determining the age of an animal is to know its birth date. In the absence of birth information, use other criteria. In the absence of birth information, use other criteria. The examination of the animals teeth is the most widely employed method to determine age. The examination of the animals teeth is the most widely employed method to determine age. Remember Mr. McMillan? What did he talk about? Remember Mr. McMillan? What did he talk about?

3 Introduction The eruption date is the time that a tooth normally breaks the gum line. The eruption date is the time that a tooth normally breaks the gum line. It is more reliable than tooth wear for determining age. It is more reliable than tooth wear for determining age.

4 Introduction Tooth wear is subject to considerable variation. Tooth wear is subject to considerable variation. Aging an animal using only this criterion is often difficult. Aging an animal using only this criterion is often difficult. That is why many people say that this animal has the teeth of an animal that is ___ years old, rather than saying that the animal is ____ years old. That is why many people say that this animal has the teeth of an animal that is ___ years old, rather than saying that the animal is ____ years old.

5 Introduction Domestic animals develop two sets of teeth. Domestic animals develop two sets of teeth. –Deciduous teeth –Permanent teeth

6 Introduction Deciduous teeth, also known as baby teeth, are typically smaller and whiter than permanent teeth. Deciduous teeth, also known as baby teeth, are typically smaller and whiter than permanent teeth. Because young animals have much smaller jaws, there are always fewer deciduous teeth than there are permanent teeth. Because young animals have much smaller jaws, there are always fewer deciduous teeth than there are permanent teeth.

7 Introduction Age estimates of horses and ruminants are based on the appearance of the lower incisors and canine teeth. Age estimates of horses and ruminants are based on the appearance of the lower incisors and canine teeth. While the eruption dates of cheek teeth (premolars and molars) are more accurate, they are seldom used. While the eruption dates of cheek teeth (premolars and molars) are more accurate, they are seldom used. The upper permanent first premolars of horses are either absent or are small rudimentary teeth, called wolf teeth, which erupt at 5 to 6 months of age. The upper permanent first premolars of horses are either absent or are small rudimentary teeth, called wolf teeth, which erupt at 5 to 6 months of age.

8 Aging Horses The incisor teeth of horses differ from those of other domestic animals since they continually erupt (to a certain age) to prevent a deficit in length. The incisor teeth of horses differ from those of other domestic animals since they continually erupt (to a certain age) to prevent a deficit in length.

9 Diagram of the horse head and teeth

10 Aging Horses The following presents important dates for aging horses. Keep in mind that these are average ages and that variations occur in many instances. The following presents important dates for aging horses. Keep in mind that these are average ages and that variations occur in many instances. –1 week old Deciduous central incisors erupt Deciduous central incisors erupt –1 month old Deciduous intermediate incisors erupt Deciduous intermediate incisors erupt –8 months old Deciduous corner incisors erupt Deciduous corner incisors erupt

11 Aging Horses 2 ½ years 2 ½ years –Permanent central incisors erupt 3 ½ years 3 ½ years –Permanent intermediate incisors erupt 4 ½ years 4 ½ years –Permanent corner incisors erupt 4-5 years 4-5 years –Permanent canines erupt (males only) 6 years 6 years –cup gone from central incisors 7 years 7 years –cup gone from intermediate incisors 8 years 8 years –cup gone from corner incisors

12 Aging Horses Beyond eight years, age determination largely becomes a matter of speculation. Beyond eight years, age determination largely becomes a matter of speculation. To determine the animals age, use several features, such as the shape of the occlusal surface or the angle between the upper and lower incisors. To determine the animals age, use several features, such as the shape of the occlusal surface or the angle between the upper and lower incisors. The shapes of the occlusal surfaces begin oval, then change to round, triangular, and biangular, as the animal ages. The shapes of the occlusal surfaces begin oval, then change to round, triangular, and biangular, as the animal ages. The angle between the upper and lower incisors when viewed from the side becomes more acute as the horse ages. The angle between the upper and lower incisors when viewed from the side becomes more acute as the horse ages.

13 Teeth at age 3 ½ and age 20

14 Aging Cattle To determine age in cattle, the lower incisors must be examined because they do not have upper incisors. To determine age in cattle, the lower incisors must be examined because they do not have upper incisors. Several key dates aid in the estimation of an animals age. Several key dates aid in the estimation of an animals age.

15 Diagram of Cattle Teeth

16 Aging Cattle Less than – 1 year Less than – 1 year 1 ½ - 2 years 1 ½ - 2 years –First permanent incisors erupt 2 – 2 ½ years 2 – 2 ½ years –Second permanent incisors erupt

17 Aging Cattle 3 years 3 years –Third permanent incisors erupt 3 ½ - 4 years 3 ½ - 4 years –Last permanent incisors erupt 5 years 5 years –All permanent incisors show wear

18 Aging Sheep and Goats The lower incisors are also used in age estimations of sheep and goats. The lower incisors are also used in age estimations of sheep and goats. Because they develop teeth at about the same age, sheep and goats have similar eruption dates. Because they develop teeth at about the same age, sheep and goats have similar eruption dates.

19 Aging Sheep and Goats Less than 1 year Less than 1 year 1 – 1 ½ years 1 – 1 ½ years –First permanent incisors erupt 1 ½ - 2 years 1 ½ - 2 years –Second permanent incisors erupt

20 Sheep and Goat Teeth 2 ½ - 3 years 2 ½ - 3 years –Third permanent incisors erupt 3 – 4 years 3 – 4 years –Last permanent incisors erupt

21 Aging Dogs and Cats The permanent teeth of dogs and cats have all erupted by the time the animal is approximately six months of age. The permanent teeth of dogs and cats have all erupted by the time the animal is approximately six months of age. While the wear of teeth is somewhat accurate in large breeds of dogs, it is often misleading, and in smaller dog breeds and cats, it is seldom used. While the wear of teeth is somewhat accurate in large breeds of dogs, it is often misleading, and in smaller dog breeds and cats, it is seldom used. The best way to determine a dogs or cats age is to know its birth date. The best way to determine a dogs or cats age is to know its birth date.

22 Canine Teeth

23 Aging Dogs Deciduous Teeth (Puppy Teeth) Deciduous Teeth (Puppy Teeth) –Incisors: 3 – 4 weeks –Canines: 3 weeks –Premolars: 4 – 12 weeks –Molars: None Permanent Teeth (Adult Teeth) Permanent Teeth (Adult Teeth) –Incisors: 3 – 5 months –Canines: 4 – 6 months –Premolars: 4 – 6 months –Molars: 5 – 7 months

24 Aging Cats 2 – 4 weeks 2 – 4 weeks –Deciduous incisors coming in 3 – 4 weeks 3 – 4 weeks –Deciduous canines coming in 4 – 6 weeks 4 – 6 weeks –Deciduous premolars coming in on lower jaw 8 weeks 8 weeks –All deciduous teeth are in 3 ½ - 4 months 3 ½ - 4 months –Permanent incisors coming in 4 – 5 months 4 – 5 months –Permanent canines, premolars, and molars coming in 5 – 7 months 5 – 7 months –All permanent teeth in

25 Review What is the difference between deciduous and permanent teeth? What is the difference between deciduous and permanent teeth? Why is tooth wear not a reliable factor when trying to determine age? Why is tooth wear not a reliable factor when trying to determine age? What is the only accurate way to determine the age of an animal? What is the only accurate way to determine the age of an animal?


Download ppt "Determining Age of Animals. Introduction The only accurate method of determining the age of an animal is to know its birth date. The only accurate method."

Similar presentations


Ads by Google