BIF Honors Dr. Tim Holt

Colorado State University veterinarian Tim Holt has performed over 350,000 pulmonary arterial pressure (PAP) tests on cattle since 1980, and made immeasurable contributions to our understanding of bovine pulmonary hypertension (BPH), also known as high-mountain disease or brisket disease. In recognition, the Beef Improvement Federation (BIF) honored Holt with one of its 2018 BIF Pioneer Awards.
BPH often causes sickness and death losses when susceptible calves or adult cattle move to high-elevation pastures in the Mountain West. Typically, the condition occurs in cattle grazing at elevations higher than 5,000 feet. In recent years though, cattle feeders and veterinarians have documented BPH in feedyard cattle at lower elevations, including High Plains feedyards located at 3,000 to 4,000 feet of elevation.
BPH is a heritable condition, and Holt’s work has helped seedstock producers and ranchers select less-susceptible cattle for mountain environments. The PAP test involves inserting a catheter into the jugular vein, through the right atrium and right ventricle and into the pulmonary artery. A transducer attached to the catheter measures the pulmonary arterial pressure.
At high elevations, low oxygen levels lead to constriction of the pulmonary artery, resulting in high PAP. High PAP ultimately leads to right-sided congestive heart failure, clinical “brisket disease” and death, unless affected cattle are quickly moved to lower elevations. Cattle have small lung capacity relative to their body mass, making them more susceptible to this condition than most other mammals. Researchers suspect that high growth rate and heavy finished weights can lead to a similar disease process in genetically susceptible feedyard cattle at lower elevations.
Holt continues to perform around 10,000 PAP tests each year, contributing to heritability studies and ongoing efforts to prevent the condition on mountain ranches and lower-elevation feedyards.
Read more about BPH in “Bovine Pulmonary Hypertension: Not Just a High-Altitude Disease,” from Bovine Veterinarian.