There are several advantages and disadvantages of cloned livestock. Most obviously, farmers can clone the most desirable animals for leanness, milk production, taste, and so on. Farmers could also select clones that are resistant to certain strains of disease. However, this lack of genetic diversity could leave the industry open to other diseases (read here for more). There is also evidence that cloned animals suffer more liver and kidney aliments, die younger, and reach puberty later (RSPCA).
Cloning of pets is probably the least controversial (though, still controversial) cloning on the market today. Since late 2001, pet cloning has become a booming commercial enterprise fetching up to $50,000USD. Cloning pets gives owners a way to keep from losing their beloved pets but some have noted that the clone of the animal you love is not the same. The memories and personality of the new creature are its own. Cloning pets can be a Pandora's Box for pet owners. One great example of this is Chance the Bull. There was a segment on This American Life about Chance in which they discuss how the clone, Second Chance, was prone to attacking its owner despite the fact that the original Chance was a very calm bull.
Finally, cloning humans, the last frontier in this scientific journey, is the most contentious of all. Scientists race to find ways to clone skin and other organs for the rich that want to remain youthful and cheat death even if only for a few years. Some say the advancement of cloning could lead to near immortality.
One thing that I think could really benefit from cloning is blood. Since the advent of blood transfusions, the biggest drawback has always been shortage of blood. Blood donors are inadequate in supply and the shelf-life of a blood is rather short. It’s not hard to find instances of blood shortages like this one in Ohio. Of course, the problem of a shortage is largely because people eligible to donate are unwilling to donate either because they lack time to go donate or because they don't like needles. There are still other problems with the blood supply. The risk of transmitting disease from donor to recipient (especially HIV) is a concern. Also, the existence of rare blood types is an issue. People with certain rare blood types may run into problems if they ever need a transfusion. If we could clone red blood cells, white blood cells, and platelets there would be no need to worry. Here are some Pros and Cons for cloning human blood:Pros
- Makes it possible to always have the necessary units of blood on hand
- Blood donations could eventually be obsolete
- Storage needs reduced because fresh units could be synthesized on demand
- No more risk of transmitting HIV and other infectious diseases via transfusion
- People with rare blood types can receive transfusions of compatible blood
- Very expensive for the foreseeable future
- Moral and religious debates over cloning