View From the Range

Colorado's Silver Spur Ranch Shares Calving and Tagging System Tips

Jennifer Carrico
By  Jennifer Carrico , Senior Livestock Editor
Silver Spur cowboy Michael Thelen tags and processes a newborn calf on the Colorado ranch. (Photo by Decky Spiller, Silver Spur Ranch)

REDFIELD, Iowa (DTN) -- While calving time has been going on for well over a month, the Silver Spur Ranch Kiowa Creek Division crew continues to watch for calves for another couple months. They breed the cows and heifers in groups so all 1,000 aren't calving at the same time.

They begin with the first-calf heifers, which are due to start calving in mid-January, but Decky Spiller, manager of the ranch in Kiowa, Colorado, said they are prepared to have this group start nearly two weeks prior to their due date.

It seems like currently a heifer bull is a shorter gestation bull instead of a lower birthweight individual, he said. "When they go full term or overdue, they aren't necessarily low birthweight calves."

At the end of February, the first-calvers are nearly complete, while other groups have started calving. Cows due with their second calf are artificially inseminated in a group to begin calving on Feb. 1 and mature cows start calving by mid-February.

The busy ranch is sharing what is going on there as part of this year's new View From the Range special series. DTN will follow a year at Silver Spur Ranch to give readers an inside look at how the ranch operates and cares for its animals. This is the second segment in the series. (See the introductory story at…).


Spiller explained when they choose bulls to use on the Silver Spur first-calf heifers, they do look at calving ease and birth weight expected progeny differences (EPDs), but they want the calves to have quality. Several heifers are kept for replacements and the best bull calves are often kept back to sell as low birthweight bulls, so they want an overall good animal that doesn't slack in other performance categories.

A very important part of selecting bulls is knowing their Pulmonary Arterial Pressure (PAP) scores, which they also get on females. PAP indicates animals with lower risk of developing high altitude disease, which in most cases results in congestive right-sided heart failure according to the American Angus Association. (Editor's note: We will visit this subject in-depth in an upcoming View From the Range.) These scores must be in the proper range for the cattle to be able to survive at the altitudes of all the Silver Spur Ranches.

Silver Spur Ranches date back to the 1800s and have divisions in Colorado, Wyoming, New Mexico, and Nebraska. The Kiowa Creek Division is known as the seedstock provider of Angus, Red Angus and Charolais genetics

Nearly all the herd bulls used are home-raised and artificial insemination (AI) sires are dependent on breed and goals for the breed. Commercially available Angus bulls are used for AI at a higher rate because the Silver Spur Angus bulls aren't quite to the point needed for AI when looking at all performance data.

"Red Angus bulls are closer to what we need and only 25% commercially available bulls are used. For the Charolais, we use about 50% Silver Spur bulls and 50% AI sires from other herds," said Spiller. Bulls used in the Range Fire program are all home-raised, either Charolais bulls on Red Angus females or bulls of the F1 cross of the two breeds are used on F1 females.

Synchronization protocols are used when artificially inseminating cows and they start with a group of replacement heifers, which is normally around 250 head each year. After these heifers are pregnancy checked and all have received a PAP test, they keep the bred heifers who meet their requirements and sell the other bred heifers in groups. The final group to be calved will be approximately 180 head.

"After we are done breeding heifers, we breed four big groups of cows, starting with two groups of 250 to 280 head each and then two more groups of about 150 head each," Spiller explained. "The last 50 to 80 cows to calve, we will give a shot of Lutylase and turn a bull in with them to get their calving date moved up. This usually moves them up by about a month and gets them back with the bigger AI groups."


If the weather permits, cows calve on the range, and within six hours of birth, newborns are processed. "We use a birthweight tape to get a birthweight. Calves are also tagged and given an Alpha-CD clostridial shot," he said. "If there's any question on if the calf received colostrum, they will be brought in and given some either from the cow or a commercially purchased product. Colostrum sets the stage for a calf's health."

During harsh conditions, all calving females are checked throughout the day and night. During nicer weather, cows will calve on their own at night, but first-calf heifers are continually checked. Shelter and live water are available where all cows are calving. During severe weather, the cows close to calving are brought into pens to ensure the pairs will be safe and have guaranteed shelter.

"As cows calve, they are paired out into a series of traps so we can ride through them daily. Once we get a group of about 60 calves, we will start branding and working these pairs. That usually starts about March 15," Spiller said. "Weather certainly predicts the health on calves and cold stress is a cause of issues down the road."


When calves are born, they receive a unique five-digit individual identification number specific to their breed and the ranch location.

The front of the tag includes the dam's identification number on the bottom, calf identification number in the middle and the AI sire code on the top. On the back of the tag, they include the birthdate, sex, and birthweight of the calf, along with the dam's identification number on the bottom.

"If we want to go out to the pasture and look for all the calves of a certain AI sire, we can easily find them without having to have paperwork with us since the information is right there on the tag," he explained.

Different colors of tags are used as well, based on the breed of the dam. Green is for Red Angus, white for Black Angus who are red carriers, pink for Charolais, blue for Black Angus, purple for Range Fire, and orange for the few Simmentals on the ranch.

When cows are pregnancy checked, each calf gets an electronic ID tag which is linked to its individual five-digit ID number. Each time an animal is weighed or treated, the EID tag can be scanned, and the information stays with the animal. Tags are also notched when the calf is doctored. A certain location is used for each kind of treatment for respiratory disease, foot rot, pinkeye, or enterotoxin. This information can become important if cattle become sick later or when they go to the feedyard, as they cannot be in the Verified Natural Beef, Non-Hormone Treated Cattle (NHTC) program.

A lot goes on at the ranch during calving. Spiller said it's important for all the crew to communicate about what's happening and everyone must be on hand to have a successful calving season.

The next edition of View From the Range will discuss vaccinations and health of the Kiowa Creek Division herd.

Jennifer Carrico can be reached at

Follow her on X, formerly known as Twitter, @JennCattleGal

Jennifer Carrico