Be Prepared For Calving Season
DR. TOM TROXEL
LITTLE ROCK, ARK.
Calving is one of the most important times on the production
calendar. Management decisions made prior to this period can influence
success at calving and ultimately profitability of an operation. Calving
difficulty (dystocia) is a very important economic problem in the U.S.
beef cattle industry.
Nutrition
The last trimester of pregnancy is when the majority of fetal growth
occurs. During this period, the nutrient requirements of the cow
increase accordingly. In particular, the last 45 days prior to calving
are a critical time. The best method to assess the nutritional status of
the cow is to monitor body condition. Ideally, most cows should enter
the calving season with a body condition score (BCS) of 5 to 6. However,
early-calving cows (January and February) and young cows (two- and
three-year-olds) should have a BCS closer to 5.5 or 6. Research has
clearly demonstrated that body condition can have a dramatic impact on
subsequent reproductive performance. If the cows are thinner than
desired, it is advisable to alter the plane of nutrition to add body
condition prior to calving. After calving, the nutrient demands
associated with lactation make it difficult and expensive to add body
condition.
A common misconception regarding pre-calving nutrition is that
feeding cows too well results in increased calving difficulty. This is
absolutely incorrect! Actually, underfeeding cows prior to calving could
increase calf scours and mortality and reduce calf survival. Along the
same vein, overfeeding can be a problem as well. Cows that are
over-conditioned actually deposit fat in the birth canal, which can lead
to calving problems.
Some research suggests that calf vigor can be influenced by
pre-calving plane of nutrition. Calves from cows on a maintenance or
high plane of nutrition got up and nursed more quickly than calves from
cows on a low plane of nutrition. Time to nurse is critical in getting
an adequate amount of colostrum in calves prior to gut closure.
Vaccination
Providing immunity to the calf via colostrum is the focus of
pre-calving vaccination programs. There are several diseases that can be
vaccinated for at this time; however, to vaccinate for every possible
disease is neither practical nor economically prudent. Consult with your
veterinarian to develop the vaccination strategy that is appropriate to
your operation.
Timing of Feeding
The Konefal Calving Method was developed by a beef producer in
Manitoba, Canada. This method involves feeding cows twice daily at
approximately 11:30 a.m. and 9:30 p.m. Using this regime, Gus Konefal
was able to get 80 percent of his cows to calve between 7 a.m. and 7
p.m.
Research at Iowa State University produced similar results. Results of
USDA research were not as dramatic, but still showed a 10 to 20 percent
reduction in the number of cows calving between 10 p.m. and 6 a.m.
Calving Management
Preparing calving facilities prior to calving is wise. The calving
area should be clean and dry and be in close proximity to shelter and
facilities needed to assist cows with calving difficulty. Maternity pens
with a head-gate, crowding gate and nursing panel can also be quite
helpful. Calf shelters and/or warming boxes should also be cleaned and
checked (wiring in particular). Once the facilities are prepared, it is
always wise to make a list of needed items and to make sure they are
accessible. Some key items would include calving jack, OB chains or
straps, iodine, tube feeder, rags or towels, light source, tags and/or
tattoo equipment, and last but not least…your IRM red book.
Colostrum
Colostrum is critical to survival of the newborn calf. The immune
system of newborn calves is not completely developed. Consequently, the
antibodies and immunoglobulins in colostrum are a substantial component
of the immune protection in newborn calves. Calves should receive 5 to 6
percent of their body weight as colostrum within 6 hours and again
within the subsequent 6 hours.
If the calves are not able to nurse or the cow’s production of
colostrum is insufficient, colostrum from other cows or commercial
colostrums supplements may be necessary. Ideally, colostrum should be
collected from cows within 24 hours of calving and fed fresh. Colostrum
can also be collected, frozen and used later. Johne’s disease can be
spread via colostrum, so caution should also be exercised when
collecting colostrum from unknown animals.
Colostrum should only be used from cows known to be Johne’s free.
When collecting colostrum, consider freezing it in “serving” sizes or
one to two quarts per container. Once colostrum has been thawed, it
should not be refrozen. Correct thawing will also help prevent the
antibodies and immunoglobulins from being damaged. Frozen colostrum
should either be slowly warmed in warm water to a final temperature of
105° to 110° F or in a microwave on medium power. In both cases, the
colostrum should be stirred frequently.
Commercial colostrum supplements are available, and research suggests
that calves fed colostrum supplements are healthier than calves that
received no colostrum. However, the level of protection was lower than
in calves fed frozen colostrum. ∆
DR. TOM TROXEL: Professor, Associate Department Head, University of Arkansas