Dexter Milk Genetics
Is A2/A2 milk better?
One hotly debated topic in the Dexter world is that of A2/A2 milk genetics...
What is A2/A2?
In short, it is one of the potential protein combinations found in milk and milk products. There are two types of protein found in cow's milk: A1 and A2. The milk proteins come in pairs and can be in any combination. Cows can produce either protein or both at once. There is no taste or visual difference in A1/A1 milk, A1/A2 milk, or A2/A2 milk. Without a microscope, there is no discernable difference for most.
Milk in stores is A1/A2 unless otherwise labeled. Every milk container on the shelf in your local grocery store is a combination of innumerable cows. The preponderance of commercial dairy cows produce A1/A2 milk, so even if there are a few A2/A2 commercial cows, most milk in your local grocery store is A1/A2.
Why does this matter?
There is new research that suggests perhaps lactose isn't the issue for those who are "lactose intolerant". The research suggests that milk protein may be the culprit behind milk-induced tummy troubles. Perhaps this is why "lactose intolerant" individuals can very often tolerate goat milk and goat cheese. Goats exclusively produce A2/A2 milk!
The most compelling argument I've seen in favor of choosing A2/A2 cows is that humans exclusively produce A2/A2 breastmilk. Knowing this, one can logically surmise that A2/A2 cow's milk might be better tolerated than A1/A1 or A1/A2. While the science isn't settled, it's certainly worth exploring further.
While there is currently no definitive scientific evidence that A2/A2 milk is better than the other types, we do understand that, based on the above logic, many people would prefer to have A2/A2 animals. So how does one know what they're getting when breeding?
A basic punnet square demonstrates the potential outcome of pairing any two animals with known alleles.
The A2/A2 trap...
What we do not want to do is treat cows that are not A2/A2 like they have a disease. Culling animals for their milk protein genetics would remove other desirable traits from our Dexter herd. For this reason, we do not exclusively select for A2/A2 genetics. We have both A1/A2 and A2/A2 animals on our farm to maintain the genetic diversity necessary for a healthy, well-structured herd.
We do understand the desire for A2/A2 cows so we make every attempt to pair our healthiest animals so we will have A2/A2 animals available for purchase from our yearly calving. We will always list the A2 status of every animal on our website. The term "obligate" indicates both sire and dam carried homozygous alleles and therefore no genetic testing was required to know the status of their offspring.
Available animals will always be linked on our "For Sale" page.