Their importance depends upon ranch management goals and selected herd performance measurements.
“Weights at birth, weaning and yearling ages are important expected progeny difference (EPD) measurements, so livestock scales are a must for seedstock producers,” says Dr. Rick Machen, Texas AgriLife livestock extension specialist at Uvalde.
“Scales will probably pay for themselves on large commercial operations if dewormers or antibiotics are used on a regular basis,” says Dr. Joe Paschal with Texas AgriLife extension service at Corpus Christi.
“These medications require an animal’s actual or estimated weight for dosage calculation. Scales can provide cost savings in preventing either overdosing or by preventing increased morbidity due to underdosing.”
Desired weights
“The ability to measure performance is a key component in all beef cow operations,” write John Arthington and James Stice.
“Regardless of size, producers must be able to identify the current status of their operation in order to make adjustments toward improvement.
Cow culling is a key management tool for herd improvement. Being able to identify the poorer-producing cows within a herd is essential.”
“It’s a good idea to weigh cattle every time they are worked, but the most important weights are birth and weaning,” says Paschal. “Birth weight is one of the factors that determine calving ease, but more importantly, birthweight is the starting point for measuring growth.
The difference between birth and weaning weights is a measure of the cow’s ability to raise a good calf. These weights help identify cows for culling and indicate whether calves have received the right nutrition.
Weaning weights may indicate a need for creep-feeding calves or improving genetics in the cowherd. If calves are sold at weaning, their weight is important at this production stage because it determines their market value.”
“Weaning weight is one of the most important, although most abused, measurements of cowherd performance,” write Arthington and Stice.
“Weaning weight is calculated in many ways; therefore, it is essential that a producer understand the method of calculation when attempting to estimate his or her production efficiency.
“Calf age is an important consideration when calculating weaning weight.
Significant variation in weaning age or breeding season can affect the reliability of using weaning weight to measure cowherd productivity.
One method of accounting for this variation is adjusting weaning weight to a constant age. A commonly used weaning age adjustment is 205 days.
To adjust, simply calculate calf gain by subtracting the calf’s birth weight from its actual weaning weight.
Then divide calf gain by calf age in days. This will be the average daily gain (ADG). Finally multiply ADG by 205 days for a uniform adjustment based on age of the calf. To do this, it is important to know the birthdate of each calf.”
“It is recommended that cows be weighed at the same time as calves,” write Tom Troxel and Bill Wallace. “The cow weight is used to calculate weaning percentage of their bodyweight.
Generally, cows that wean a high percentage of their bodyweight are more efficient and profitable than cows that wean a low percentage.
“Weaning percentage is the calf’s adjusted 205-day weight divided by the cow weight times 100.
Mature cows should wean 50 percent of their bodyweight when their calves are 205 days old.
As cows have increased in size, it has become harder to accomplish that goal.
A 1,000-pound cow will more likely wean a 500-pound calf than a 1,400-pound cow weaning a 700 pound calf (205-day adjusted weight).”
“As cow size increases, the efficiency percent usually decreases,” write Troxel and Wallace. “There’s also a negative relationship between efficiency percent and calf breakeven (cost of producing a pound of beef).
As efficiency percent goes down, calf breakeven goes up. The efficiency percent calculation is very important. A cattle producer would more likely want to keep a replacement heifer from a cow that weaned 50 percent of her bodyweight than one that weaned 38 percent of her bodyweight.”
Types of scales
“Livestock platform scales are composed of three primary parts – indicator, platform and load bars,” says Terrell Miller of Cattlesoft Inc. “Indicators for platform scales come in various degrees of sophistication and in three different price categories.
The most economical indicators, currently costing between $700 and $800, are read manually. Weights are taken from the indicator and recorded on a pad, spreadsheet or notebook. They can also be entered manually into a computer.”
Miller usually recommends an indicator from the middle price range and sells the most units from this group.
These indicators, costing between $1,200 and $1,500, are ideal for basic weighing with electronic identification reader integration. They have internal memory that can be downloaded into a computer format for additional analysis.
Indicators ranging in price from $2,000 to $5,000 are the most expensive and comprehensive.
They allow recording and viewing complete animal history while cattle are being weighed. Reports and graphs can be designed right on the indicators.
Load bars, containing sensors, are designed for use with platforms, crates, cages, in alleyways or in squeeze chutes. They currently cost between $1,100 and $1,800.
“If a producer doesn’t mount their load bars under a squeeze chute, a weighing platform is needed which adds another $500 to $700 to the scale price,” says Miller. “Weighing platforms are usually made of aluminum with skid-resistant surfaces. The aluminum makes them durable, lightweight and easy to clean.”
Livestock platform scales are beneficial technology for cow-calf operations if a ranch is large enough to produce a positive return on the investment.
The purchase price must fit the ranch budget and the scale must result in a positive change in profits for it to be a wise buying decision. 
References omitted due to space but are available upon request. Click here to email an editor.
PHOTOS
1. A squeeze chute with sensor bars underneath.
2. A scale indicator with digital read-out.
3. Indicator mounted in waterproof box on side of barn a few feet away from squeeze chute.
4. A load sensor attached to bottom of squeeze chute.
5. The connection for cable from indicator. Photos courtesy of Robert Fears.
