Keep a watchful eye at calving time
Surveillance and decision-making are key during birthing, believes University of Nebraska-lincoln Extension veterinarian Dave Smith.
“Be monitoring the progress of calving and have some kind of rule for when you intervene,” Smith says, warning that every calf being born doesn't need to be pulled. “There's risk of harm by doing that. You just need to see evidence of progress.”
For example, if you check a cow and see that the toes are pointing forward and the nose is starting to show, and come back five minutes later and more of the feet and nose are showing, that's a good sign. But if there isn't progress being made, producers need to be ready to act.
“A lot of people wait so long before they call a veterinarian that there's nothing they can do,” Smith says. Early recognition of a calving problem is critical, which is why Smith recommends having a vet talk through the birthing process with everyone responsible for calving cows. It's important for people to know what they can do, what should be on hand and when to contact a vet.
The only thing more variable than the weather at calving time is the equipment available from ranch to ranch. One outfit may have just a horse and rope, others a complete hospital sickpen. Dave Smith, University of Nebraska-Lincoln Extension veterinarian, recommends producers have basic equipment on hand, including:
- soap and water
- obstetrical (OB) gloves
- esophageal tube-feeder
- restraint for the cow
It's extremely important to keep equipment clean, Smith states, particularly esophageal feeders and OB equipment.
When do producers need to be concerned about weather affecting newborn calves? When the temperature is outside of a calf's thermonetural zone.
The thermonetural zone is a temperature range where calves don't need extra energy or effort to stay warm or cool down, thus not suffering distress from being unable to adjust temperature.
Newborn calves are not as prepared as older animals to thermo-regulate their body temperature. When air temperature gets too far from the thermoneutral zone, calves cannot keep up, becoming chilled or heat stressed.
The thermoneutral zone for newborn calves is between 10° and 26°C (50° to 80°F); month-old calves' range is between 0° and 23°C (32° to 75°F).
University of Nebraska-Lincoln Extension veterinarian Dave Smith compares the thermoneutral zone to shirt-sleeve weather for humans. When the temperature is in that range, we are comfortable. If it's outside the range, we either put on a jacket or seek an air conditioner.
Hot box — or not?
A “hot box” used to revitalize extremely cold-exposed calves can be very effective — for saving an occasional calf. But if it's part of the management plan, ranchers need to be wary of the high pathogen load to which they're exposing susceptible calves.
A calf that is bright, alert and bawling probably doesn't need the extra attention. But sluggishness, slow response and lack of a suckle reflex are all reasons to intervene, says Dave Smith, University of Nebraska-Lincoln Extension veterinarian. To go along with that, if it's very cold, the calf needs to be warmed up and given colostrum.
“It's those two components: taking care of its body temperature and taking care of the energy,” Smith says.
Testing for profit potential
Shaun Sweiger, DVM points to another pre-weaning tool — pre-calving actually — that can reduce stress and economic loss on multiple fronts: testing for persistent infection with Bovine Viral Diarrhea virus (PI-BVDv).
“Given the research that exists, hopefully producers are testing for PI-BVDv prior to the breeding season so they're not re-creating the problem if they have one,” Sweiger says.
He points to research from Colorado State University that indicates PI-BVDv infection can cost $10-$24/breeding cow across the entire herd, stemming from abortions, late breeding and sub-par breeding performance. In his own practice, Sweiger says calves testing negative for PI-BVDv — at stocker level — are gaining 0.5-0.75 lbs. more/day on average than those exposed to a PI-BVDv calf.
So the average test cost of about $4/head can pay substantial returns. At mimimum, Sweiger suggests that cow-calf producers test their calf crop once to know if the problem exists in their herd.
— Wes Ishmael