The Bagpipe - American Highland Cattle Association

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MANAGEMENT
calving the colostrum is consumed by the calf and the quality of colostrum given. This can significantly decrease the
number of calves with inadequate antibodies to fight infection well (down to only 10% to 20% with insufficient levels).
Tubing with an esophageal feeder is generally more efficient than bottle feeding when done properly. Aiding all beef
calves to receive adequate colostrum is an intensive and exhausting endeavor. As such, selecting sires with calves that
are quick to get up and nurse, as well as keeping cows that have good udder conformation and good mothering instincts
become extremely important in the management of any beef herd.
Delay and minimize the infectious dose to which the calf is exposed. Most of the agents causing scours are
ubiquitous: the calf will ultimately be exposed and will hopefully develop immunity. Any factor which allows for an
increase in the number of organisms in the environment will increase the likelihood of the calves to contract scours.
The agents of scours are spread by ingestion, aerosol-inhalation or contamination of the navel. Sanitation and
ventilation are critical factors for maintaining healthy calves. If using calving pens, keep them immaculate. Clean and
dry them between animals. Treat the navel with iodine soon after birth. If you use an esophageal feeder to give
colostrum to newborn calves, use a separate one for the sick calves. Always tend to healthy animals first, leaving the
sick calves until last. Wash hands and clean up after handling sick animals.
You can also minimize exposure by minimizing the density of susceptible calves. Exposure of the various organisms
to drying or sunlight can drastically limit their survival in the environment. Cows can be chronic carriers of the viral
agents causing scours and intermittently shed low numbers of virus into the environment. The viruses survive very
well in the pasture or calving area. The incubation period in the calf is short, about 3 days and then the scouring calves
infect others by shedding the virus in their diarrhea in very high numbers. Calves out of first calf heifers are more
susceptible to these viruses, usually due to the fact that their colostrum is not of the same high quality as the older
cows. To reduce exposure, move newly calved pairs out to pasture to physically spread out the calves. If scours develops
in that group, leave it together but don’t make new additions; newer cow/calf pairs should go to another new pasture.
Do not bring in sale barn calves to graft onto mothers with a dead calf. Often neonatal sale barn calves are colostrum
deprived and have already been exposed to a whole host of infectious agents.
Reduce stress factors. The primary stress factors for newborn calves are difficult delivery, lack of energy intake,
wetness and wind. Calves can handle severe cold if they are dry and protected from the wind. Highland calves have a
heavy hair coat to protect them from the elements but if that hair gets soaked, it becomes a liability. Protection can be
given to calves by means of portable calf sheds in the grazing area. It is essential that they be cleaned out or moved
periodically.
Calf scours can be prevented and controlled but this can only be through proper management practices.
Causes of Calf Scours
E. coli: bacteria normally present in the intestines of all mammals. Certain strains can cause diarrhea, others do not.
This agent is always present in the intestinal tract and usually only causes disease as a secondary infection following
viral agents or intestinal irritant.
There are 3 main disease forms:
Colisepticemia describes a disease where E. coli spreads from the intestines though the calf’s body and causes
abscesses in the brain, eyes, kidneys and joints. This occurs when the newborn calf ingests it in manure, mud or
other material before or along with getting colostrum. Extremely difficult to treat successfully; it can be
prevented by calving in clean dry areas, making sure that the cows’ udders are clean, and keeping colostrum clean
and refrigerated or frozen. This can be caused by any strain of E. coli.
Enterotoxigenic E. coli (ETEC) is caused by a specific strain (K99 and a few others) that attaches to the
intestinal cells and causes them to pump excess fluid into the gut lumen, where it is subsequently passed
(hypersecretory diarrhea). This process can pump so much fluid into the gut of the calf that it can die before
outward signs of diarrhea appear. This diarrhea is almost the only diarrhea to occur within the first 3 days of
life. It can be prevented by feeding colostrum containing K99 antibodies. This entails vaccinating the cows prior
to calving.
Enteropathogenic E. coli (EPEC) is a specific strain that attaches very tightly to the intestinal wall and
produces various poisons that cause both excess secretion and malabsorption of fluid. There is no vaccine
available.
Rotavirus diarrhea: This virus is ubiquitous throughout neonatal cattle populations. The disease is characterized
by a brilliant yellow, voluminous, pudding-like stool later becoming more watery. Calves can be affected as young as
12 hours after birth but most cases will be between 3 and 30 days old. Calves will be severely depressed and lose
their appetite. Diagnosis depends upon laboratory methods.
There are several vaccines available for rotavirus; one involves vaccinating the cow at very specific periods prior
to calving so that the colostrum is fortified with antibodies against rotavirus. This method still requires rapid and
adequate colostrum consumption by the calf, as these antibodies are not passed through the placenta as in other