Rafter N Ranch, Inc

Abortions in Cows

Abortions should be a major concern to cattle producers. Not only is the calf lost, but abortion may be an indication of a larger problem. Abortions can have physical (kick or butt), nutritional, toxic, genetic, or infectious causes. Producers need to know the cause of any abortion and should consult a veterinarian immediately.

Obviously when a cow aborts, you know that the calf is lost, adding no income to the enterprise. The question to ask is why she aborted. There are many reasons why cows abort, and you need to determine the cause whenever possible. There are several causes of abortion that need to be considered.

The one cause that can cost you dollars (or even your cow herd) is infectious abortion. Many of the causes of infectious abortion can be prevented with vaccination programs. Diseases causing abortion (such as infectious bovine rhinotracheitis (IBR), bovine viral diarrhea (BVD), brucellosis (Bangs), leptospirosis, and vibriosis) have inexpensive vaccines available. Other infectious causes of abortions are trichomoniasis, anaplasmosis, ureaplasmas, and possibly nycoplasmas. There is a vaccine for anaplasmosis, but it is not routinely used nor widely recommended. Vaccines for the other diseases are not readily available. The danger in infectious abortions is that they can spread rapidly throughout the herd, causing financial disaster. Also, in many cases, these infectious diseases are spread from farm to farm by animal to animal contact across fences, contact with diseased tissue, or even varmints such as birds, dogs, cats, or other wild mammals. You should also take care in using live or modified live vaccines. If used at the wrong time, they can cause abortions.

The noninfectious causes of abortion are less serious, but just as costly. Sporadic losses from moldy feeds that contain mycotoxins cause abortions. If feed smells or looks bad and has bacterial growth, it may be best not to feed it to pregnant cows. The risk of possible abortion may be too great. If there is any doubt about molds in feed, have the feed tested before using it. Contact your county Extension agent for help in getting a good feed sample and having it tested.

Other causes of abortions are recessive or lethal genes, poison (i.e., excessive nitrates from feed or water, pine needles, acorns, poisonous plants), hormonal imbalances with the cow, injuries received from being hit or bumped, and/or falls, and some from nutritional deficiencies. In particular, deficiencies of vitamins A and E and the micronutrient selenium can cause abortions.

Unless you know a specific cause of abortions, such as an injury, anaplasmosis, or some other identifiable problem, you need to get your veterinarian involved. The cost of not seeking professional help is potentially too great. You should contact your veterinarian as soon as possible and save as much tissue (fetus, afterbirth, etc.) as possible. Be careful to use rubber gloves when handling aborted tissue. Some abortive diseases are infectious to humans. Also, there tends to be a higher incidence of abortions in heifers. These are generally noninfectious abortions caused by hormonal and reproductive tract deficiencies. Producers usually cull out the problems when these cows are young.

To help prevent and help control abortions:

1. Keep nutrition on a high plane.
2. Avoid bloodlines of cattle that carry known recessive genes that cause abortion.
3. Be careful with moldy feeds.
4. Get on a regular vaccination program to prevent infectious reproductive diseases.
5. If you see a cow or heifer that has aborted, find out why, if possible. It is better to know. What you do not know can harm your enterprise.