Cows milk in general has been associated with increased production of mucous in the body. A new report shows, not all cows milk is created equal - even if it is organic and raw. 
"Newer" breeds of cows produce milk containing a protein (beta-CM-7), which can stimulate mucus glands in your digestive and respiratory tracts.
According to Professor Keith Woodford, Beta-CM-7 has also been implicated in other far more serious health problems: Typ 1 diabetes, autism, schizophrenia, impaired immune function, autoimmune disease, and heart disease.
These "newer" breeds experienced a mutation of a particular amino acid a long time ago, and are the most commonly found cows in dairy farming in the US and Europe. The older breeds, such as Jersey's Guernsey, Asian and African, do not have this mutation.
One way around this issue is to get to know local farmers in your area, that have older breed cows or switching to goats milk.
Or get your nutrients from where the cows get them: Greens!
1 cup of Kale has the same amount of Calcium as 2/3 cup of milk.....plus many co-factors associated with calcium metabolism! A study revealed that calcium from kale was 40.9% absorbed versus 32.1% from milk. 
Love your Green Leafy Vegetables ;-)
Jeannette von Johnsbach
1 Bartley and McGlashan, Division of Otolaryngology, Manukau District Health
Board, New Zealand
2 Heaney RP, Weaver CM. Calcium absorption from kale. American Journal of
Clinical Nutrition 1990; 51:656-657