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NAHMS Dairy 2014 study reveals calf insights

More information from the National Animal Health Monitoring System (NAHMS) Dairy 2014 study was revealed at the 2016 Joint Annual Meeting of the American Dairy Science Association and the American Society of Animal Science.

NAHMS researchers Jason Lombard and Natalie Urie presented several sets of calf-related data at the conference’s Production, Management, and the Environment: Health and Welfare Symposium. The Dairy 2014 study collected calf health and performance data for 12 months, from farms located in 13 of the top dairy states across the United States.

Among the unique, calf-related findings of the Dairy 2014 study were:

1.      Average Daily Gain (ADG) in heifer calves

·         Parity of the dam significantly affected heifers’ ADG. Calves born from first-lactation heifers gained less than those born to second- or third-lactation cows.

·         Calves incurring illness, twin calves, and calves provided a lower-protein diet had a lower ADG than their herd mates.

·         Bedding type had a significant effect on heifer ADG, with calves provided no bedding or sand bedding having a lower ADG than those provided straw, hay, shavings, or mixed bedding.

2. Calf mortality and morbidity

 ·         The average calf mortality of the farms in the study was 5%. This figure did not include calves that died within 24 hours of birth.

·         About 28% of calves experienced one disease event prior to weaning. Digestive disease was the most likely culprit, representing 44.2% of clinical disease cases.

·         The average age of mortality was 24.4 days of age, with digestive disease cases mainly occurring around two weeks of age and respiratory disease around five weeks.

·         Of the calves that died, 25% died without any clinical signs recorded before death.

3. Colostrum quality

 ·         77.4% of the colostrum samples being fed to calves were considered excellent quality, with IgG levels >50 g/L.

·         Third-lactation cows were found to provide significantly better quality colostrum than first- and second-lactation cows or commercial milk replacer.

·         While only 7% of herds used heat treatment, it was found to significantly increase serum IgG levels in calves.

The researchers concluded that opportunities for improving colostrum delivery included heat-treating colostrum to boost serum IgG levels; and testing colostrum prior to feeding to ensure excellent quality.