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When Does a Lamb Become an Adult Sheep?

A lamb will become a sheep at around the age of 12 months when it will start to develop the traits of an adult sheep.

Some lambs will become adults earlier since most lambs grow up fully by the age of 6 months, but they are still called lambs until they are one year old.

Lambs are particularly known for producing high-quality lamb meat that’s popular around the world.

The reason why lamb meat is so popular is that it’s tender and more tasteful than other types of meat. Lambs are baby sheep and they are considered to be adults when they reach the age of 12 months.

When Does a Lamb Become an Adult Sheep

When Does a Lamb Grow Up?

A lamb grows up fully by the age of 5-6 months but is still considered a lamb until the age of 12 months.

Some lambs might take longer to grow up and develop adult features, such as developing sexual maturity as well as growing up fully, developing larger teeth, and other features.

The rate of growth of lambs is fastest in the first few months of its life. When the lamb is born, it will usually weigh around 9 pounds, but it will grow up quickly and reach the weight of at least 50 pounds in a few weeks. 

At the very beginning of a lamb’s life – especially the first few weeks, they will start growing quickly. The growth will be fastest in the first few weeks of a lamb’s life when it will grow for up to 250 grams per day. In just eight weeks, a lamb might gain about 45 pounds of weight thanks to its growth.

The growth of the lamb might be complete after six months when it will reach the average weight and size of an adult sheep – which stands at around 100 pounds. Some sheep will grow larger and heavier than that, especially the rams, which might reach weights of up to 350 pounds when fully grown.

However, some features of the lamb are still not fully developed by 6 months or even later. They will reach sexual maturity at about the age of 6 months but will not be allowed to mate until they are at least 18 months old. Also, their teeth will continue growing until well into adulthood.

What are the Differences Between Lambs and Sheep?

There are some key differences between lambs and sheep, including:

  • Age
  • Size and weight
  • Sexual productivity
  • Horns
  • Coat thickness
  • Diet

These are all key differences between lambs and sheep. The first and most obvious difference is, of course, the age. An adult sheep is at least 12 months old while lambs are essentially baby sheep younger than 12 months. There might be some fluctuations, but these are the general numbers.

Another obvious difference is the size and weight. The adult sheep will be much larger and heavier than lambs. Adults will reach weights of up to 300 pounds and even more for the males, while lambs might only weigh up to 50 pounds. However, lambs will fully grow up at least until the age of 8 months.

You’ll also see differences in various features of the body, such as horns, teeth, and coat thickness. Adults develop horns, have larger teeth, and usually have thicker coats than lambs. Also, adults are sexually active and are able to reproduce, while lambs are not yet able to do so.

Another notable difference between an adult sheep and a lamb is the diet. Because lambs don’t develop teeth early, they will have to supplement their diet with milk, especially in the first few days and weeks. Adult sheep are ruminants, so they will eat grass, leaves, and other similar types of food.

How Old are Lambs When Slaughtered?

Usually, lambs are slaughtered at the ages of between four and twelve months old. This is when the meat of a lamb is already developed enough to be consumed.

As you might already be aware, lamb meat is highly popular around the world. It is the meat of a baby sheep and since this meat is preferred to be eaten when it’s still tender, the meat is sometimes collected from lambs that are still very young. The youngest age at which a lamb might be slaughtered is four months old.

However, most farmers opt to slaughter their lambs at the age of at least five months old. The most common age for this is between 5-8 months of age. Any later than that would usually mean a slight deterioration in the quality of meat and it would also become slightly tougher than it is for lambs.

At the age of 12 months and older, the meat of a slaughtered sheep becomes mutton meat. This is when the meat starts to become tougher and not as flavorous as before. Mutton is also not as valuable as lamb meat, so farmers prefer to slaughter their sheep when they are still lambs.

What Makes a Sheep an Adult?

A sheep becomes an adult when it is fully grown up, when it develops sexual reproduction capabilities, and when it starts to grow its coat, teeth, and its horns.

It’s hard to pinpoint an exact moment when a lamb becomes an adult, but there are several signs to watch.

The most common sign that a lamb has become a sheep is their breeding capabilities and their size. Most lambs become capable of breeding at the age of around 6 months but will usually not yet breed at that age. Another sign is their appearance and size. The larger the lamb is, the closer it is to reach its adult stage.

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A lamb becomes a sheep when it is fully grown, it reaches breeding capability, and when it grows its teeth and coat. This usually happens at the age of around 12 months old when we start to consider lambs as adult sheep.

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