County Agent Update

Weak Calf Syndrome

Calving season provides all types of challenges for the rancher. Nothing is more frustrating than when a normally delivered calf is slow to get up and nurse. This could be due an extended labor, a large sized calf, a premature calf, cold weather, wind chill or other factors. Helping the calf nurse or providing colostrum replacement/supplement usually helps the calf eventually show some vigor.

However, sometimes the calf dies even with human assistance. While 5 percent death loss of the calf crop may be considered normal, it certainly is an economical loss. When losses are greater than normal, and they share the same symptoms of normal delivery and born alive calves but are weak and eventually die, it could be weak calf syndrome.

Weak calf syndrome is associated with reduced nutrition to the mother. Cows are usually in reduced body condition. A cow with a body condition score of 3 or 4 would have more incidences of weak calf syndrome than cows with more body fat. However, the lack of body fat isn’t the only issue involved, although it is a good physical sign to observe.

Adequate protein in the ration for the pregnant cow may help. A classical study by Bull and coworkers from the University of Idaho reported less weak calf syndrome with higher level of protein fed to the mother 60 days before calving. Late gestation rations with more than 10% crude protein had a 0.6% incidence of weak calf syndrome while rations less than 10% crude protein had 8.5% incidence.

When protein content in feeds is low, it indicates other nutrients may also be less than required. These nutrients include energy, calcium, phosphorous, cooper, zinc, selenium, as well as other minerals and vitamins. Providing a vitamin and mineral supplement to pregnant cows is encouraged. Managing rations for increased weight gain (or avoiding weight loss) with extra protein and energy will help. Weather stress can play into weak calf syndrome. A healthy, good conditioned cow fed a balanced ration can still give birth to a weak calf because of an associated weather event.

Issues that arise due to weather events may include:

1. The cow has reduced feed intake due to a weather event that lasts longer than a day

2. Combine that with the growing fetus and the increased energy and nutrient demand during the last few days or weeks of pregnancy

3. Reduced feed intake due to the fetus competing with the rumen for internal body cavity space

4. Reduced competition for feed during the last few days before calving

5. Lack of bedding, windbreak or barn space to reduce nutrient demands due to stress as a result of adverse weather.

When the cow eats less nutrients, she has less nutrients available for the fetus. Adverse weather events might lead to weak calf syndrome since the mother may not be eating enough for two. Better nutrition during late pregnancy will help reduce weak calf syndrome. This information is from Dr. Karl Hoppe at the Carrington Research Extension Center.