The snowstorms that plagued ranchers in the Northern Plains this spring seem like a distant memory. Warm weather and the prospects for better cattle markets heading into fall do have a way of helping the mind forget about the snow, mud, and difficult days. But as ranchers and cattle feeders begin to prepare for fall weaning and marketing, it may be worth one last look back at conditions at calving time this spring and those conditions could impact the health and performance of calves entering the feedlot this fall.

As we think about the conditions this spring, there’s a strong likelihood that the passive transfer of immunity that normally occurs from dam to calf was less than optimal. The combination of winter weather conditions, poor pasture production last year, and a shortage of higher quality feedstuffs resulted in many cows that were in less than ideal body condition. Thinner cows have been shown to produce colostrum that contains fewer immunoglobulins. The conditions the calves were born in also plays a role in immunoglobulin intake and absorption. Calves under cold stress take longer to nurse and may not be as aggressive when they do stand to nurse. When taken together a convincing case can be made that there were a large number of calves born last spring where the passive transfer of immunity has been compromised.

Conventional wisdom might suggest that once these calves get to the weaning phase the impacts of that rough start are gone. Actually results from research studies suggest that the effects of poor transfer of immunity last much longer than originally thought. A study conducted by the USDA Meat Animal Research Center found that calves that received little to no colostrum at birth were three times more likely to get sick in the feedlot post-weaning compared to their contemporaries with normal colostrum intake.

A study using dairy heifer calves in Arizona showed at even longer-term impact of colostrum intake. In that study heifer calves fed an increased amount of colostrum at birth produced about 1200 more pounds of milk when measured over the first two lactations. Considering what we know about how early development and management affects carcass quality, it is certainly plausible that problems with immunoglobulin intake and passive transfer of immunity could show up as poorer performing cattle with reduced quality grades.

How does this affect how to best manage weaned calves this fall? It’s probably a safe assumption that calves born during the worst conditions this fall will be at a higher risk for disease compared to more normal conditions. Consulting with a veterinarian about possibly adjusting receiving and weaning protocols to account for higher risk levels would be a very prudent approach. If these calves are more susceptible to disease problems, paying extra attention to minimizing stress and easing their transition into the feedlot would also be warranted, and well worth the extra effort.

Weaning and receiving calves can be challenging even under ideal conditions. While we don’t know what the level of environmental stressors we may experience this fall, we do know what many of the calves that will be marketed went through this spring. Considering what the market value of feeders will likely be this fall, spending additional time and planning before the first group is gathered or the first trucks arrive looks to be time well spent.

Source: Warren Rusche