Factors That Affect Fertility: Abortion
Script of Select Sires' Reproductive Moment Program
on DairyLine Radio Which Aired June 1, 2006
With Ray Nebel,
Senior Reproduction and Herd Management Specialist, Select Sires Inc.

Ray, when it comes to factors that affect fertility, one of those is abortion.

Yeah, Bill. Many times we don’t have a good handle on abortions because we don’t really catch that cow when she has aborted until some time down-stream, either that we are drying her off or we come for a second preg check and find she is no longer pregnant.

How about if you first talk about the early abortion, or in the first two trimesters.

We always think of two factors, such as the natural service herds that bulls are running vibriosis and trichomoniasis is more apt to occur with contact from male to female. A very common one that’s gotten a lot of press over the past few years is leptospirosis. Leptospirosis, a new strain or species, has been isolated and we have vaccines now called Lepto Hardjo. Our normal Lepto vaccines had five different seriotypes, and the Hardjo seriotype is one of the five. We think of venereal diseases such as IBR and BVD, Bovine Viral Diarrhea, and there is also a protozoan neospore that can cause abortions, usually in the first six months. Other odd things that we might think of are micotoxins that usually occur at any time, but maybe more susceptible at six months of pregnancy, and then we do see some mineral and vitamin deficiencies, but I would have to say that those are pretty rare.

That is early term, what about late term?

Okay, in the late term abortions brucellosis, or course most states in the United States would be free of brucellosis, maybe we will see viral diseases such as IBR or BVD, we see use of some hormones such as cortisone or prostaglandin in synchronization programs that get injected in the wrong cows; more often we will see an injury that would affect later term abortions than early abortions. So, when we look at some diagnostic ways to look at this, of course blood testing has been the old stand-by, probably not very successful to determining what is causing the abortion but it should always be looked at as one of our first means of identifying if it is a leptospirosis, IBR, BVD or a neospore. Necropsy of a fresh fetus—if a fetus can be collected before it gets too contaminated or it deteriorates, bring it to a diagnostic lab—again the success rate is low, but we still need to try. Closely observing the environment, including the pasture, the nitrate accumulation in weeds and water sources, all can be sources that can cause abortion. Taking vaginal swabs by the veterinarian to be submitted for microplasam, ureaplasam, and possibly vibriosis and trichomoniasis infections.

The last one I will talk about is micotoxins – mold. Usually in the fall you will see the mold growth because of the right temperature and moisture, but many of these molds can cause abortions and they will be throughout the gestation, but can occur in late gestation also. If you get into an abortion situation of course your veterinarian and the Select Reproductive Solutions specialist can help to really start eliminating some of these causes and pinpoint where we need to go.

That is Ray Nebel, senior reproduction and herd management specialist at Select Sires