The final months of gestation are critical for cow health and calf development
The last trimester in a cow’s gestation can be critical to the success of her calf. Additional preparation and management on the part of the producer will go a long way toward her health, and the health of her calf.
Cows need an increase in groceries during the last trimester to support themselves and their calf. If they went into their pregnancy well-conditioned, chances are it won’t be a drastic change.
“For many cows in the herd, meeting third-trimester nutritional requirements isn’t too difficult,” Dr. Shane Gadberry, ruminant nutrition specialist with the University of Arkansas Extension, explained. “Nutritional needs do increase during this time from about a 7-percent protein diet to a 9-percent protein diet.”
He explained the type and stage of forages play a factor in protein-improved forage varieties can often meet the 7- to 9-percent protein requirement, but overly mature grasses or true native grasses may not have sufficient protein for late gestation.
Meeting diet digestible nutrient needs may be a little more challenging than meeting protein needs.
“While protein needs only increase by a couple of percentage points, as cows approach calving, their diet digestibility needs increase to 6 to 8 percentage units from 52-to 58-percent TDN over that three-month period before calving,” Gadberry explained. “Some cows may be on the thin side at calf weaning, and they may need special attention leading up to calving. If there are several thin cows in the herd, it may be economically feasible to separate them from fleshier cows, if they are going to need supplement in addition to forage, to get them back to a good body condition for calving. These cows need to be confirmed pregnant before spending the additional money in supplements.”
Some producers may worry about overfeeding cows during the last trimester and creating birthing issues. Gadberry and Andy McCorkill, livestock field specialist with the University of Missouri Extension say that is unlikely.
“Most of the nutritional requirement increases we see are going into final trimester are fetal development; basically, we’re feeding the cow to grow the calf she’s carrying. Although it is possible to over feed a cow in any stage of production and cause problems, I think there is more of a tendency to underfeed out of fear of causing an increase in calving difficulty rather than overfeeding,” McCorkill said. “This practice is just as apt to cause problems caused by thin heifers that don’t milk and don’t breed back. Small weak calves that lack energy to survive are another side effect of underfeeding cows in the last trimester of the pregnancy.”
Poor nutrition in the final trimester has lasting impacts.
“If the cow isn’t properly fed, the calf is more likely to be small and weak at birth, which is often coupled with a malnourished cow that won’t produce enough, or quality, colostrum or milk, making the situation worse,” McCorkill said. “The setback doesn’t stop there, it leads to carcass, growth and frequent health issues for the rest of the stunted calf’s life.”
Housing and Shelter
Whether or not the shelter requirements change during the last trimester will depend on if the producer is working with mature cows or first-calf heifers.
“With mature cows, there isn’t much need to do anything special in the way of housing; having some timber cover to get out of the elements is advisable. Preferably, calving pastures would be located near working facilities or a barn to leave the cow and new calf in if the need arises to provide any assistance,” McCorkill suggested. “With heifers, it’s more important to keep them closer to facilities as it’s their first calving experience and may need help with the calving process or pairing up with the calf.”