Trace Minerals for California Beef Cattle 

University of California, Cooperative Extension

Kern County Mineral Data

Se deficiency tends to be concentrated in central and eastern Kern county with adequate Se levels in western Kern county. Random samples from 5 herds (total 50 head) in western Kern county had an average whole blood Se level of 0.229 ppm. A similar sample set from 7 herds (total 70 head) from central and eastern Kern county had an average whole blood Se level of 0.042 ppm. This latter average was skewed due to a single herd averaging 0.124 ppm. When that single herd is excluded the average for 6 herds in central and eastern Kern is 0.0287 ppm. Levels below 0.04 are usually considered deficient and responsive to supplementation.

In general western soils tend to be sufficient or excessive in Se. Plants grown on those soils or on soils derived from that area, or using water originating from those areas will tend to be adequate or excessive in Se. In contrast, plants grown in central and eastern Kern tend to be deficient in Se. Crops grown in central or eastern Kern that receive soil or water of western origin may be higher in Se than anticipated due to location. In those cases, Se status of cattle may be adequate despite location in central and eastern Kern.

Cu status is marginal with wide variation, suggesting potential deficiency in some areas.  Serum values from samples (n=34) at the California Veterinary Diagnostic Lab (CVDL) averaged 0.73 ppm (SD 0.24).  Liver samples were 147 ppm (SD 133).  Values below 35 ppm are deficient.  Thus, the overall average is adequate.  However, the variation suggests some cattle are Cu deficient.  Further testing is needed to identify specific areas and herds.

A small number (27) of samples have been submitted to the California Veterinary Diagnostic Lab and they averaged 1.03 ppm Zn (SD 0.45).  This would be considered adequate.

Insufficient data are available for conclusions.