Yes, we need to manage dry cows! So often, this is a group of animals that get minimal attention from herdsmen. I’d like to help you understand what happens to the cow at dry-off.
Then you will understand the herdsman tips I’ve suggested. These tips should help you to do a better job of managing dry cows.
1. We dry off the cow to cause her to switch her nutrient use from milk production to growth of the calf within the uterus. The fetus grows more during the last three months of gestation than at any other time; all extra nutrients the cow consumes during the dry period above her maintenance requirements go toward growth of the fetus.
2. Abrupt stoppage of milking causes a cow’s udder to dry up. The milk that accumulates in the udder after two to three days of not milking her puts pressure on milk-producing cells in the udder. This pressure is the signal for the udder to stop converting blood to milk. Within a week to 10 days, the milk-producing cells are turned off and the udder shrivels up or involutes.
3. Bacteria can get into the udder during the dry period. The two most susceptible times are within the week after dry-off and again within a week prior to calving.
4. Antibodies are like soldiers that float around in the blood stream, all the time ready to attack enemy bacteria. These antibodies concentrate in the udder during the last weeks of the dry period.
There are 100 times more antibodies in the udder at calving than at any other time in the lactation cycle of the cow.
That is why it is so important to harvest colostrum, which is the first milk produced by the cow at calving, to feed to newborns. It is antibody-rich and protects the calf from infection.
5. The dry period is like time off or vacation for the cow to replenish tissues that she will need to maximize milk production after calving:
a. The lining of the stomach (rumen) has worked hard for the past 10 to 12 months while consuming tons of feed. The internal rumen wall gets remodeled during two months of low-energy dry cow feed to prepare for the nutrient-rich high-cow feed she will receive in her ration after calving.
b. Milk-producing cells in the udder are worn out after producing thousands of pounds of milk during her lactation. Through the dry period the udder gets thousands of new secretory cells ready for the high milk production period that starts after calving.
c. Legs are tired and feet have overgrown like long finger nails. The dry period is the time to rest legs and reshape feet to allow the cow to walk for months during high milk production with minimal risk of lameness.
1. Palpate every cow at dry-off to confirm that she is still pregnant. The fetus is fairly large at this time and the artery that supplies blood to the uterus is as big as a pencil.
Ask your owner or veterinarian to teach you how to palpate the fetus, the cotyledons or the uterine artery to be sure the cow is still pregnant.
Abortions during lactation can go unnoticed; always confirm the cow is pregnant before drying her off.
When in doubt, have the veterinarian or an experienced person confirm your suspicion that a cow is not carrying a normal calf.
2. Change the daily routine of groups of cows that will be dried off one or two days before actually drying them. Upset the cows’ routine, so they eat less, reduce milk production and sense something is different.
Do things such as change feed, group “cows to dry” together and separate them from their herdmates, vaccinate, trim feet and move them to the dry pen with new herdmates. These techniques signal the cow to stop milk production (see “FACTS #2” above).
3. Dry treat cows with specialized dry cow tubes. These medications are formulated with higher levels of antibiotics to remain in udder tissue longer than lactating cow tubes.
Since these dry cows will not be milked for another month or two, the concentrated antibiotics persist longer to kill lingering bacteria but won’t contaminate milk.
In some cases, your owner may want you to use teat sealants in addition to antibiotic tubes; these form a barrier so bacteria can’t penetrate the teat end, reducing mastitis that can occur immediately after dry-off or immediately prior to calving (see “FACTS #3” above).
4. Use clean, hygienic treatment routines to dry treat cows. You can cause mastitis by forcing bacteria into the udder when you do not clean the teat end with an alcohol swab prior to treating.
When you are not clean, the race between bacteria that get into the udder because you did not use aseptic procedures and the antibiotic you infuse will always be won by the bacteria. (see “FACTS #3” above).
5. Do not re-treat dry cows at any time after the initial dry treatment. Studies have demonstrated this causes mastitis because it re-opens the teat end.
(Remember, a natural plug forms at the teat end, preventing bacteria from penetrating at dry-off).
In addition, because of udder involution, there is no milk to transport the second tube of antibiotics high up into the udder where bacteria hide (see “FACTS #2” above).
6. Vaccinate cows at dry-off and when moving them to the close-up pens.
Because antibodies concentrate in the udder prior to calving (see “FACTS # 4” above), vaccinating dry cows maximizes antibody concentration in colostrum and gives newborns the highest level of protection when we feed this colostrum to them within four hours after birth.
7. Don’t forget to check your dry cows daily. The rest they deserve (see “FACTS # 5” above) can turn into problems if you are not observant. Learn to trim feet correctly or be certain that your off-farm hoof trimmer is doing the right job reshaping feet.
Not every cow needs to have every foot trimmed. Monitor feedbunks to be sure dry cow feed is delivered properly every day.
Find early and treat aggressively the few dry cow problems (e.g. pink eye, lameness, swollen quarter, abortions) that occur in every herd.
Your owner will appreciate and respect you more because you now know how to manage his or her dry cows better. EL