Justin Sexten: Alternative Feeding Value
Today most would suggest the most value one can add to cattle is time. The reality of an expiring commodity continues to challenge nearly every segment of the cattle business. In times like this the value the stocker and background segments offer the beef supply chain is in clear view. These shock absorbers of the beef industry will be key to helping work through the supply challenges of the next few months.
Adding time to cattle offers a couple different outcomes. The first is simply owning them longer and marketing the resulting heavier calf. The alternative is management modifications that may not change the ownership time but rather reduce the market weight goal. For some the current value of gain calculations suggest the opportunity for the stocker backgrounder lies closer to option two where advancing age pays better than increasing mass.
This makes the decision to provide supplemental feed on pasture a bit trickier this year. For some, limited distillers grains availability or increased cost due may cause your nutritionist to seek other supplement options. For others providing additional nutrients is contrary to the profit opportunity of time versus performance.
In reality for many operations the reason for supplementing cattle on pasture goes beyond increasing animal performance or pasture stocking rates. Supplement provides intrinsic “values” such as simplified pasture movement, easier cattle inventory management or enhanced health detection.
The final point leads us to the subject of a recent paper from Will Kayser and co-workers at Texas A&M. In this Journal of Animal Science article they evaluated several behaviors into a statistical process control model to diagnose BRD earlier than simply looking for sick cattle. A unique aspect of this experiment was rather than developing prediction models looking backward at treatment data, they inoculated calves to establish a known day of exposure to respiratory disease.
Unlike previous studies comparing the cowboy’s ability to pull calves relative to historic treatment records, they determined when technology could diagnose a calf’s deviation from normal, knowing when and what animals were exposed. The research group looked at feeding behavior, movement patterns and rumen temperatures to diagnose BRD onset. The methods of evaluation were also part of the experiment in order to categorize which technology methods are best suited to measure items of interest.
The most accurate early diagnosis method was achieved using feed intake or time spent at the feed bunk. Other traits such as time the animal spent eating, how often and fast they visited the bunk after feeding in addition to rate of feed consumption were accurate predictors more often than not. Similar results were reported with rumen temperature.
Movement based measurements such as standing, ruminating and resting were good at diagnosing animals without BRD but not as effective at diagnosing sick animals. Accuracy is the combination of sorting both the ill and healthy. For technology to have value, it must be predictive in both the sick and healthy to minimize treating healthy calves and find those sick calves early.
Another interesting aspect of these data was the mild disease state. Only one calf exhibited clinical symptoms of BRD. Even under this low disease state, the models using feed intake, feed bunk visits and duration and active feeding behavior all indicated a deviation from normal in less than one day after exposure. Imagine detecting BRD one day after exposure in cattle not showing symptoms.
An important note, one must determine normal before a diagnosis can be made using deviation from normal. These calves were monitored for 28 days prior to disease exposure to establish a normal baseline. Despite the longer observation time this and previous work indicate 4 days of baseline monitoring provides adequate indication of normal.
Feed intake is a challenging measure to capture, requiring specialized bunks and to some extent a deviation from normal operation feeding systems. An interesting aspect of these data was the discovery one could monitor bunk visit duration as a proxy for feed intake. Proximity and movement measurements to and from the bunk are much simpler to capture than actual feed intake.
Providing supplement to calves on pasture should not be compared to this technology focused experimental approach. However, staying aware of cattle’s response to the feed truck continues to provide operational value beyond nutrition as the technology catches up. The keen eye of a feed truck driver continues to serve as an early barometer of health.