Strawberry Milk

Blood in the Milk at Calving

I milked out cow #612 this morning after she delivered her calf yesterday. Her calf was born on a beautiful spring day in an open green pasture, but failed to adjust to the nursing way of life. The cow was more than happy to let the calf nurse, but sometimes, the newborn does not instinctively start enjoying the free milk buffet. I tube fed colostrum last night and today, his vigor is decent, but his belly is empty and her udder is full. I wish I did not have to intervene and that he would suddenly have the desire to nurse from his dam, but it is time to run the cow into a chute.

The Examination and Hand Milking Routine
I examined #612 and began prepping her udder for milking. Once the udder was clean and dry, I checked to see that all four teat sphincters were open and healthy. Each quarter was stripped a bit to examine the milk. The first milk, colostrum, will normally be thick, sticky and a little more yellow than the milk that will flow later in the lactation. Today, cow #612 produced “strawberry milk.”

Strawberry Milk
Pink-tinged milk or “strawberry milk” occurs when red blood cells (RBCs) gain access into the lactation system. There are varying reasons this may occur, but luckily most of them are incidental and have no effect on the safety of the milk for the calf to drink. Even though we do not see strawberry milk very often, a small amount of blood in the milk after calving is considered to be a normal physiologic process.

Causes of Strawberry Milk
Ruling out the different causes of strawberry milk will help to determine if the milk is safe for a calf to drink. There are quite a few reasons why blood will enter the udder or teat and become large enough in volume to be noticeable in the milk. We need to consider a few of the following common causes:

1. Trauma to the udder (one or more quarters)
2. Mastitis (infection of one or more quarters)
3. Clotting factor deficiency (FXI)
4. Diapedesis (vascular pressure or leaking)

Cow #612 is eating and drinking well. Her body temperature is normal and besides the off color, the milk looks and smells otherwise normal with no visual milk or blood clots. The udder is soft and the teats are pliable with no pain, heat, swelling or excessive fluid build-up (edema). At this point, I am comfortable in ruling out the first two categories: trauma and mastitis.

A clotting factor deficiency (FXI) can play a role in causing blood to leak into the dam’s first milk. The hereditary clotting factor malfunction was first discovered in Holstein cattle in Ohio in 1969. Other symptoms that may occasionally occur include persistent bleeding from the umbilical cord or slower clotting behavior of blood following castration or dehorning in affected calves. Cows that have inherited the deficiency will have pink-colored colostrum. Although, neither #612 nor the herd sire are known to be from Holstein decent, I suppose it is possible, yet unlikely.

The increased blood supply to the udder prior to calving may lead to blood leaving the tiny vessels and moving into the milk gland, called diapedesis. When diapedesis occurs, the volume of RBCs in the milk can become so numerous that the milk becomes pink-tinged in color. Upon settling, the milk will take on an ombre color pattern with an orange cream on top, pinkish milk and a deep red sediment as the RBCs settle out. Typically the blood will not persist in the milk for more than 14 days. Although pink-tinged milk is rejected by human consumers, the calf will not object to the milk at all. Good news, the milk is definitely safe for the calf to drink. So, if diapedesis is the cause of cow #612’s strawberry milk, everything is fine. I coaxed the calf to nurse until the light bulb went on (farm life idiom). He finally began to bump her udder, wag his tail and suckle until he was full and content.

If you are faced with a case of strawberry milk, consult your veterinarian. A physical examination may be warranted, depending on the severity and concurrent problems such as trauma, edema or anemia. Medical therapy treatments can help to decrease pain and inflammation associated with trauma. Antibiotics may be prescribed to treat mastitis or in the case of Factor XI, medications such as calcium or progesterone might be necessary to control excessive bleeding.