How to Determine Age in Small Ruminants Based on Tooth Structure? Age Determination from Teeth in Sheep and Goats
How to Determine Age in Small Ruminants Based on Tooth Structure? Age Determination from Teeth in Sheep and Goats
Prepared by: Anadolu Birlik Domestic and International Sacrifice Services Inc.Subject: Approximate Age Determination in Sheep and Goats Based on Tooth StructureContent Type: Informative / Livestock and Sacrifice GuideUpdate Date: August 11, 2026
One of the most practical methods for determining the age of sheep and goats is by examining the mouth, especially the incisors in the lower jaw. If the animal's date of birth or reliable farm records are available, these records are given priority. However, in cases where records are not available or cannot be verified, the transition of teeth from deciduous to permanent teeth is an important indicator in approximately determining the animal's age.
The Ministry of Agriculture and Forestry also states that properly kept farm records provide definitive results in determining the age of animals; in the absence of records, tooth development is an important method of age determination.
Which Teeth Are Examined in Small Ruminants?In sheep and goats, the lower incisors in the front part of the mouth are evaluated for age determination.
Small ruminants do not have front incisors in their upper jaw. Instead, the upper jaw has a hard dental cushion. The lower incisors help with cutting grass and consuming feed. In sheep, a total of 8 lower incisors are the primary area used for age determination.
These teeth are initially milk teeth. As the animal grows, the milk teeth are replaced by larger and stronger permanent incisors.
The basic logic of age determination in sheep and goats can be thought of simply as follows:
Milk teeth → First pair of permanent teeth → Second pair of permanent teeth → Third pair of permanent teeth → Fourth pair of permanent teeth
This change generally allows us to track the animal's age between approximately 1-4 years. However, since the timing of tooth eruption can vary depending on breed, nutrition, environment, and the animal's developmental status, age determination from teeth does not provide a precise birth date.
Sheep Age Chart Based on Dental Structure Approximate Age Condition of Teeth General Assessment 0–1 year 8 primary incisors Permanent incisors have not yet changed 1–1.5 years 2 permanent teeth replace the 2 primary teeth in the middle First pair of permanent teeth emerges Around 2 years 4 permanent incisors Second pair has also changed Around 3 years 6 permanent incisors Third pair has changed Around 4 years 8 permanent incisors All front incisors are permanent; “full mouth” appearance 5 years and older Wear and spacing of permanent teeth Age can only be estimated approximately Advanced age Significant wear, breakage, or loss of teeth “Broken mouth” appearance may occurThese ages are approximate values. The New Mexico State University sheep age determination guide states that pairs of permanent incisors emerge approximately at 1, 2, 3, and 4 years of age respectively; however, this timing can vary by approximately 6 months.
How to Tell if a Sheep is 1 Year Old?When the animal reaches approximately 1 year of age, the two deciduous incisors in the exact center of the lower jaw begin to change.
The narrow and small deciduous teeth are replaced by two larger, wider, and more prominent permanent incisors.
Therefore, the presence of:
2 permanent + 6 deciduous teeth in the animal's mouth
is consistent with an animal around 1 year old.
The eruption of the first pair of permanent teeth usually occurs between 12–18 months.
How to Identify a 2-Year-Old Sheep?During the second year, the second pair of deciduous incisors also changes and becomes permanent.
In this case, the lower front section of the animal shows:
4 permanent + 4 deciduous teeth
This appearance is typical for a sheep approximately 2 years old.
However, it is not accurate to say "exactly 24 months old" based solely on the number of teeth. Because there can be individual differences in the timing of tooth replacement.
How to Identify a 3-Year-Old Sheep?With the replacement of the third pair of incisors with permanent teeth:
6 permanent + 2 deciduous teeth
the appearance is formed.
This condition is generally seen in sheep around 3 years old.
How to Identify a 4-Year-Old Sheep?Around 4 years of age, the last pair of deciduous incisors are replaced by permanent teeth.
Thus, all 8 incisors in the lower jaw are permanent teeth.
This appearance is called "full mouth" in animal husbandry.
How to Estimate Age from Teeth After 5 Years?Since all permanent incisors have erupted after 4 years of age, simply asking "how many permanent teeth are there?" is no longer sufficient.
After this stage, the following characteristics are evaluated:
Degree of tooth wear,Increased spacing between teeth,Shortening of teeth,Loosening of teeth,Broken or fallen teeth,Gum recession,Changes in the animal's feed consumption.As wear and spacing increase in older sheep, an approximate estimate of age can be made. However, it is not possible to determine the exact age from teeth alone at this stage. South Dakota State University Extension also states that after the age of 4, age can be approximately assessed based on wear, spacing, and damage to the teeth.
What Does "Broken Mouth" Mean? In sheep and goats, especially those of advanced age, excessive wear, breakage, or loss of some incisors can occur.
In animal husbandry, this condition is referred to as "broken mouth."
However, the presence of a single broken tooth does not directly mean the animal is old. A true assessment of broken mouth should consider the overall condition of the teeth, wear, gaps, and changes in other teeth.
Age Determination in Goats Based on Tooth StructureIn goats, age determination primarily involves evaluating the transition of the lower jaw incisors from deciduous to permanent teeth.
Generally:
Approximately 1 year: First pair of permanent incisors,Approximately 2 years: Second pair,Approximately 3 years: Third pair,Approximately 4 years: Fourth pair and complete permanent incisor structure.This method is largely applied similarly in sheep and goats. The Alabama Cooperative Extension System also reports that in sheep and goats, one pair of deciduous incisors is replaced by permanent teeth each year until the age of four.
How to Check the Age of a Sacrificial Small Livestock by Checking its Teeth? There's an important distinction here:
Estimating an animal's biological age is not the same as evaluating the age requirement for the sacrifice ritual.
In Türkiye, the Ministry of Agriculture and Forestry's guides on sacrifices state that for sheep to be sacrificed, it is sufficient for them to be older than 6 months in terms of appearance and as developed as their mother or an adult ewe.
For goats, it is stated that they must have reached one year of age to be sacrificed. These points are also included in the Ministry's current information on sacrifices.
Therefore, especially when choosing a sacrificial animal:
The question "How many teeth does it have?" alone is not sufficient.
The animal's species, age, ear tag information, records, and whether it meets the necessary conditions for a sacrificial animal should be evaluated together.
Why Does Determining Age by Teeth Not Give Definitive Results?Tooth change is an important biological indicator, but it is not a birth certificate.
Factors that can affect the timing of tooth eruption and replacement include:
Breed,Nutrition,Genetic structure,Animal's growth rate,Environmental conditions,Raising conditions.
New Mexico State University states that the timing of permanent tooth eruption can vary by approximately six months.
Therefore, for example, the presence of two permanent incisors suggests that the animal is approximately one year old or older; however, a definitive conclusion such as "exactly 365 days old" cannot be drawn solely by looking at the teeth.
How to Check the Age of an Animal When Buying?When buying small ruminants, instead of simply opening the animal's mouth and counting its teeth, multiple pieces of information should be considered together as much as possible.
1. Check the Ear Tag NumberIt is important to check the official registration information using the animal's ear tag number.
The Ministry of Agriculture and Forestry states that information such as the animal's species, breed, gender, age, and vaccination information can be accessed via the ear tag number through the TARIMCEBİMDE application.
2. Examine the teethThe incisors in the lower jaw should be checked for:
Whether they are deciduous or permanent,How many pairs of permanent teeth are present,The state of wear,Whether there are any broken or missing teeth.
3. Look at the animal's overall developmentDental assessment should not be considered independently of the animal's overall body development.
4. Rely on recordsIf reliable birth and farm records are available, these are a stronger indicator of age than approximate estimates made from teeth. The Ministry of Agriculture and Forestry also considers well-maintained farm records as essential information for age determination.
Short Age Reminder ChartWhen checking the front incisors in sheep and goats, the following chart provides a practical reminder:
All deciduous teeth → Less than 1 year old / approximately 1 year old
2 permanent incisors → Approximately 1 year old
4 permanent incisors → Approximately 2 years old
6 permanent incisors → Approximately 3 years old
8 permanent incisors → Approximately 4 years old
Significant wear, spacing, and fractures in 8 permanent teeth → Approximate assessment for 5 years and older
This chart is an approximate age determination guide and does not replace the official birth date.
Conclusion: Teeth are the Most Practical Indicator of Age in Small Ruminants, But Not the Only CriterionIn sheep and goats, the incisors at the front of the lower jaw are an important indicator of age determination. The replacement of deciduous teeth with permanent teeth, one pair per year during the first four years, makes it easier to determine the approximate age of the animal.
1 year old → 2 permanent teeth2 years old → 4 permanent teeth3 years old → 6 permanent teeth4 years old → 8 permanent teeth
After the age of four, wear, spacing, breakage, and tooth loss are evaluated rather than the number of teeth.
However, especially when purchasing sacrificial animals, it is not correct to consider dental examination alone sufficient. Ear tags and official records, the animal's species, general development, and relevant age requirements for sacrificial animals should be evaluated together.
Therefore, the healthiest approach to making a conscious choice of sacrificial animal is:
“Ear tag record + official information + dental check + general health and development status of the animal”
a holistic evaluation in this manner.
Sources and Expert InformationRepublic of Turkey Ministry of Agriculture and Forestry – General Directorate of Food and Control: Sacrificial Animal Guide. The Ministry states that official records are important in determining the age of sacrificial animals and that dental development can be used if records are not available.
Republic of Turkey Ministry of Agriculture and Forestry – Bursa Provincial Directorate of Agriculture and Forestry: “Sacrifice Guide with TarımCebimde.” Official information on age determination in sacrificial animals and age requirements for small ruminants as sacrificial animals.
Sarah Pitassi, Jennifer A. Hernandez Gifford, Craig Gifford, and Marcy Ward – New Mexico State University: Sheep Production: Age Identification. An educational resource explaining the relationship between age and permanent incisors in sheep.
Jaelyn Whaley – South Dakota State University Extension: Mouth Sheep for Age and the Value of Dental Condition. Age determination from teeth, assessment of complete and broken mouths in sheep.
Matthew Claeys and Sharon Rogers – North Carolina State University Extension: Sheep Facts. The relationship between age and deciduous and permanent tooth structure in sheep.
Alabama Cooperative Extension System: Herd Health Management – Dairy Goats and Sheep. Tooth replacement and age estimation in sheep and goats.
Editorial note: This content is for informational purposes only. Age determination from teeth provides approximate results. Official age information should be based on the animal's registration and ear tag information.
One of the most practical methods for determining the age of sheep and goats is by examining the mouth, especially the incisors in the lower jaw. If the animal's date of birth or reliable farm records are available, these records are given priority. However, in cases where records are not available or cannot be verified, the transition of teeth from deciduous to permanent teeth is an important indicator in approximately determining the animal's age.
The Ministry of Agriculture and Forestry also states that properly kept farm records provide definitive results in determining the age of animals; in the absence of records, tooth development is an important method of age determination.
Which Teeth Are Examined in Small Ruminants?In sheep and goats, the lower incisors in the front part of the mouth are evaluated for age determination.
Small ruminants do not have front incisors in their upper jaw. Instead, the upper jaw has a hard dental cushion. The lower incisors help with cutting grass and consuming feed. In sheep, a total of 8 lower incisors are the primary area used for age determination.
These teeth are initially milk teeth. As the animal grows, the milk teeth are replaced by larger and stronger permanent incisors.
The basic logic of age determination in sheep and goats can be thought of simply as follows:
Milk teeth → First pair of permanent teeth → Second pair of permanent teeth → Third pair of permanent teeth → Fourth pair of permanent teeth
This change generally allows us to track the animal's age between approximately 1-4 years. However, since the timing of tooth eruption can vary depending on breed, nutrition, environment, and the animal's developmental status, age determination from teeth does not provide a precise birth date.
Sheep Age Chart Based on Dental Structure Approximate Age Condition of Teeth General Assessment 0–1 year 8 primary incisors Permanent incisors have not yet changed 1–1.5 years 2 permanent teeth replace the 2 primary teeth in the middle First pair of permanent teeth emerges Around 2 years 4 permanent incisors Second pair has also changed Around 3 years 6 permanent incisors Third pair has changed Around 4 years 8 permanent incisors All front incisors are permanent; “full mouth” appearance 5 years and older Wear and spacing of permanent teeth Age can only be estimated approximately Advanced age Significant wear, breakage, or loss of teeth “Broken mouth” appearance may occurThese ages are approximate values. The New Mexico State University sheep age determination guide states that pairs of permanent incisors emerge approximately at 1, 2, 3, and 4 years of age respectively; however, this timing can vary by approximately 6 months.
How to Tell if a Sheep is 1 Year Old?When the animal reaches approximately 1 year of age, the two deciduous incisors in the exact center of the lower jaw begin to change.
The narrow and small deciduous teeth are replaced by two larger, wider, and more prominent permanent incisors.
Therefore, the presence of:
2 permanent + 6 deciduous teeth in the animal's mouth
is consistent with an animal around 1 year old.
The eruption of the first pair of permanent teeth usually occurs between 12–18 months.
How to Identify a 2-Year-Old Sheep?During the second year, the second pair of deciduous incisors also changes and becomes permanent.
In this case, the lower front section of the animal shows:
4 permanent + 4 deciduous teeth
This appearance is typical for a sheep approximately 2 years old.
However, it is not accurate to say "exactly 24 months old" based solely on the number of teeth. Because there can be individual differences in the timing of tooth replacement.
How to Identify a 3-Year-Old Sheep?With the replacement of the third pair of incisors with permanent teeth:
6 permanent + 2 deciduous teeth
the appearance is formed.
This condition is generally seen in sheep around 3 years old.
How to Identify a 4-Year-Old Sheep?Around 4 years of age, the last pair of deciduous incisors are replaced by permanent teeth.
Thus, all 8 incisors in the lower jaw are permanent teeth.
This appearance is called "full mouth" in animal husbandry.
How to Estimate Age from Teeth After 5 Years?Since all permanent incisors have erupted after 4 years of age, simply asking "how many permanent teeth are there?" is no longer sufficient.
After this stage, the following characteristics are evaluated:
Degree of tooth wear,Increased spacing between teeth,Shortening of teeth,Loosening of teeth,Broken or fallen teeth,Gum recession,Changes in the animal's feed consumption.As wear and spacing increase in older sheep, an approximate estimate of age can be made. However, it is not possible to determine the exact age from teeth alone at this stage. South Dakota State University Extension also states that after the age of 4, age can be approximately assessed based on wear, spacing, and damage to the teeth.
What Does "Broken Mouth" Mean? In sheep and goats, especially those of advanced age, excessive wear, breakage, or loss of some incisors can occur.
In animal husbandry, this condition is referred to as "broken mouth."
However, the presence of a single broken tooth does not directly mean the animal is old. A true assessment of broken mouth should consider the overall condition of the teeth, wear, gaps, and changes in other teeth.
Age Determination in Goats Based on Tooth StructureIn goats, age determination primarily involves evaluating the transition of the lower jaw incisors from deciduous to permanent teeth.
Generally:
Approximately 1 year: First pair of permanent incisors,Approximately 2 years: Second pair,Approximately 3 years: Third pair,Approximately 4 years: Fourth pair and complete permanent incisor structure.This method is largely applied similarly in sheep and goats. The Alabama Cooperative Extension System also reports that in sheep and goats, one pair of deciduous incisors is replaced by permanent teeth each year until the age of four.
How to Check the Age of a Sacrificial Small Livestock by Checking its Teeth? There's an important distinction here:
Estimating an animal's biological age is not the same as evaluating the age requirement for the sacrifice ritual.
In Türkiye, the Ministry of Agriculture and Forestry's guides on sacrifices state that for sheep to be sacrificed, it is sufficient for them to be older than 6 months in terms of appearance and as developed as their mother or an adult ewe.
For goats, it is stated that they must have reached one year of age to be sacrificed. These points are also included in the Ministry's current information on sacrifices.
Therefore, especially when choosing a sacrificial animal:
The question "How many teeth does it have?" alone is not sufficient.
The animal's species, age, ear tag information, records, and whether it meets the necessary conditions for a sacrificial animal should be evaluated together.
Why Does Determining Age by Teeth Not Give Definitive Results?Tooth change is an important biological indicator, but it is not a birth certificate.
Factors that can affect the timing of tooth eruption and replacement include:
Breed,Nutrition,Genetic structure,Animal's growth rate,Environmental conditions,Raising conditions.
New Mexico State University states that the timing of permanent tooth eruption can vary by approximately six months.
Therefore, for example, the presence of two permanent incisors suggests that the animal is approximately one year old or older; however, a definitive conclusion such as "exactly 365 days old" cannot be drawn solely by looking at the teeth.
How to Check the Age of an Animal When Buying?When buying small ruminants, instead of simply opening the animal's mouth and counting its teeth, multiple pieces of information should be considered together as much as possible.
1. Check the Ear Tag NumberIt is important to check the official registration information using the animal's ear tag number.
The Ministry of Agriculture and Forestry states that information such as the animal's species, breed, gender, age, and vaccination information can be accessed via the ear tag number through the TARIMCEBİMDE application.
2. Examine the teethThe incisors in the lower jaw should be checked for:
Whether they are deciduous or permanent,How many pairs of permanent teeth are present,The state of wear,Whether there are any broken or missing teeth.
3. Look at the animal's overall developmentDental assessment should not be considered independently of the animal's overall body development.
4. Rely on recordsIf reliable birth and farm records are available, these are a stronger indicator of age than approximate estimates made from teeth. The Ministry of Agriculture and Forestry also considers well-maintained farm records as essential information for age determination.
Short Age Reminder ChartWhen checking the front incisors in sheep and goats, the following chart provides a practical reminder:
All deciduous teeth → Less than 1 year old / approximately 1 year old
2 permanent incisors → Approximately 1 year old
4 permanent incisors → Approximately 2 years old
6 permanent incisors → Approximately 3 years old
8 permanent incisors → Approximately 4 years old
Significant wear, spacing, and fractures in 8 permanent teeth → Approximate assessment for 5 years and older
This chart is an approximate age determination guide and does not replace the official birth date.
Conclusion: Teeth are the Most Practical Indicator of Age in Small Ruminants, But Not the Only CriterionIn sheep and goats, the incisors at the front of the lower jaw are an important indicator of age determination. The replacement of deciduous teeth with permanent teeth, one pair per year during the first four years, makes it easier to determine the approximate age of the animal.
1 year old → 2 permanent teeth2 years old → 4 permanent teeth3 years old → 6 permanent teeth4 years old → 8 permanent teeth
After the age of four, wear, spacing, breakage, and tooth loss are evaluated rather than the number of teeth.
However, especially when purchasing sacrificial animals, it is not correct to consider dental examination alone sufficient. Ear tags and official records, the animal's species, general development, and relevant age requirements for sacrificial animals should be evaluated together.
Therefore, the healthiest approach to making a conscious choice of sacrificial animal is:
“Ear tag record + official information + dental check + general health and development status of the animal”
a holistic evaluation in this manner.
Sources and Expert InformationRepublic of Turkey Ministry of Agriculture and Forestry – General Directorate of Food and Control: Sacrificial Animal Guide. The Ministry states that official records are important in determining the age of sacrificial animals and that dental development can be used if records are not available.
Republic of Turkey Ministry of Agriculture and Forestry – Bursa Provincial Directorate of Agriculture and Forestry: “Sacrifice Guide with TarımCebimde.” Official information on age determination in sacrificial animals and age requirements for small ruminants as sacrificial animals.
Sarah Pitassi, Jennifer A. Hernandez Gifford, Craig Gifford, and Marcy Ward – New Mexico State University: Sheep Production: Age Identification. An educational resource explaining the relationship between age and permanent incisors in sheep.
Jaelyn Whaley – South Dakota State University Extension: Mouth Sheep for Age and the Value of Dental Condition. Age determination from teeth, assessment of complete and broken mouths in sheep.
Matthew Claeys and Sharon Rogers – North Carolina State University Extension: Sheep Facts. The relationship between age and deciduous and permanent tooth structure in sheep.
Alabama Cooperative Extension System: Herd Health Management – Dairy Goats and Sheep. Tooth replacement and age estimation in sheep and goats.
Editorial note: This content is for informational purposes only. Age determination from teeth provides approximate results. Official age information should be based on the animal's registration and ear tag information.