When nearly 2,000 cows start calving, it can be a heyday or a mayday. Terry Forst and her crew find more heydays since adjusting calving seasons, watching nutrition and monitoring calves closely.

Forst manages the Stuart Ranch, which has operations near Caddo, OK, and Waurika, OK. To get better returns from the land and cattle, and to increase labor efficiency, she's moved the herds to two calving seasons.

"We use 60-day fall and spring calving seasons," she says. "This lets us concentrate breeding seasons, keep the cows in better body condition, have more uniform weaning times and sell calves in a narrow timeframe."

A similar fall and spring schedule works for the Fuhrmann Brothers operation, near Gainesville, TX. Edward, Paul and Andy Fuhrmann run a combined seedstock and commercial outfit calving about 280 head a season.

Cows get a 90-day calving period, heifers get 75 days. Fall calving starts in late August, the spring session begins mid-February. First-calf heifers calve when they're two years old and follow the same schedule as cows. Heifers will be moved into the cow herd when their first calf is weaned.

"Generally, two-thirds of the calves are born in the first 30 days of the season," Paul says. "Most are from natural service, although we do use a limited amount of AI."

To minimize calving difficulty, Andy says they breed cows to bulls with birthweight EPDs of 85 and heifers to birthweight EPDs of 65-70.

Makes Sense There are benefits to spring and fall calving and pitfalls, too.

"Late spring calving has warmer temperatures, but can be wet" says Peter Chenoweth, Kansas State University (K-State) veterinarian and professor. "Forage resources are matched to cow requirements better than early spring or winter.

"Late winter, or early spring weather can be extreme, but marketing options are well established," he adds.

The veterinarian adds fall calving is a good time for reducing weather stress.

Caring For Calves Forst starts calving fall heifers about Aug. 16. While the last calf may not drop until Oct. 16, more than 75% of the calves are born in the first 30 days.

At 60 days old, they're vaccinated, branded, castrated and dehorned. Two weeks before weaning, they're re-vaccinated and dewormed with a pour-on. Steers get implanted and calfhood vaccinated when they're turned on to pasture. Heifers also get a calfhood vaccination.

The Fuhrmanns follow an intensive birth monitoring program, combing pastures twice daily to check heifer and cow conditions and looking for newcomers.

"As soon as a calf is dry and has nursed, we tag and weigh it, and iodine the umbilical cord; treat for fire ants as well, if we need to," Andy says. "Because of the drought, we've had to watch for dust pneumonia."

Vaccinations are given to cows prior to calving. At weaning, they vaccinate calves with blackleg, hemophilus, IBR, PI3, BVD and BRSV. Overall, they follow the herd health recommendations made by Texas A&M University.

Whether it's spring or fall calves, Forst and her crew are adamant about incorporating Total Quality Management (TQM) practices.

"We use subcutaneous injections in the neck region. We're always changing needles. We constantly remind ourselves that improper injections are a hit to both us and the industry."

Forst says cows scheduled for September and October calving are generally in a body condition (BC) of a high 6. The crew tries not to rotate pastures with the cows until the calves are more than 60 days old. This lets forages stockpile and puts the cows in a BC of 5 to 6 by the time bulls are turned out Dec. 1.

"We pull the bulls at the end of January and the cows are kept on a maintenance program so we don't lose body condition," Forst says. "Winter annuals start coming on in February and March while we're feeding a 38% protein supplement and hay as needed."

Spring calves follow a similar procedure and are generally weaned in October to go on wheat pasture.

Cow body condition is watched closely at Fuhrmanns' as well. "We're feeding a ryegrass silage that we got by overseeding bermuda with ryegrass," Edward says. Their goal, Paul says, is a minimum of 2 lbs. of protein into each cow per day. They also use alfalfa hay depending on availability.

"To get good calves, it takes genetics management, good recordkeeping, health management, nutrition and range management," Andy says. "Computer recordkeeping is a good tool to make overall decisions, but it still takes hands-on individual calf management."

Nutrition On Target Nutrition is key, according to Mike Sanderson, a K-State veterinarian.

"Just about anything you vary from a nutrition standpoint has an effect on calf health," Sanderson says. He says the Fuhrmanns and Forst are on track by closely watching BC scores and nutrient requirements.

"You can divide a cow or heifer's nutritional needs into four periods," he says. "Each has a definite impact on how an unborn calf will develop or how a nursing calf will perform."

He describes the periods as: * From calving to 85 days postpartum - the highest nutritional need of cows and heifers. Cows should calve at least in a BC of 5, heifers in a BC of 7. If BC drops below 4, it can hurt calf vigor.

* The next 125 days - often in a summer grass situation. Nutrient requirements drop 10% or more. If the grass is high quality, mineral supplement is all that's needed.

* The next 105 days - post weaning, non-lactating cow. Her nutrient requirements are lowest. A maintenance diet is recommended.

* 50-60 days prior to calving - the second-highest nutrient requirement period. She needs a balanced ration or reproductive performance is harmed.

"Cows and heifers in good nutritional shape produce the highest quality colostrum," Sanderson says. "It's important that the calf suckle and get all the colostrum within the first six hours."

He adds it's important to vaccinate cows for Campylobacter, Leptospira, Trichomoa and BVD. For heifers, he suggests brucellosis, vibrio/lepto, four-way modified live (BVD, IBR, BRSV, PI3) and a 7-way Clostridial vaccine plus booster.

Strict Culling Procedures Forst uses a no-holds-barred culling approach. "My cows must meet my requirements and fit my environment," she says. "Any no-breeders get sent to town, as do those that lose calves. I'll allow a cow to miss one calf if it's caused by a management error, but that's all the leeway I give. We also cull any undesirable calves, whether it's for performance, temperament or anything else. All the calf management in the world won't mean much if we let the quality drop," she adds.

A 91% natural-service rebreeding rate on cows and heifers, despite drought conditions this year, evidences Forst' calf-to-cow quality management. The Fuhrmanns have similar culling criteria. Bad temperament, poor mothering and poor calves will cull a cow.

The Fuhrmanns and Forst concur that a total package is what makes the whole deal work. That includes genetics, nutrition, cow health, calf health, vaccinations and good pastures.

"It's putting a lot of common sense to work that helps us come out ahead," Forst adds.

No matter what season you select for calving, Peter Chenoweth, a veterinarian and professor with Kansas State University (K-State), says the period immediately after birth is critical.

A 1997 NAHMS beef survey found that 58% of calf mortality from birth to weaning occurs within 24 hours of birth; 78% occurred within the first three weeks after birth, Chenoweth says.

"It's been shown that weaning weights can be 35 lbs. lower in calves that experience a morbidity incident between birth and 45 days of age. These results highlight the importance of proper calving season management."

When it comes to calving time, both Chenoweth and fellow K-State veterinarian Mike Sanderson recommend:

* Calve cows and heifers separately so you can watch heifers closely.

* Calves cows and heifers somewhere besides wintering grounds. It decreases pathogen accumulation.

* Make sure calving pastures are adequately drained.

* Minimize pathogen build-up in dystocia pens. Clean them often.

* Consider calving when weather is less stressful.

Regardless of when you calve, Chenoweth suggests that by monitoring calving and newborns closely, you'll reap more rewards on the selling end.