News

■ What is this research about?

For Japanese Black ("Wagyu") calves, weaning (the time they switch from their mother’s milk to solid food like grass) is a very important period that brings huge changes to their bodies. During this weaning phase, calves easily lose temporary nutritional balance, which often leads to slower growth or a higher risk of getting sick. This has been a major challenge in cattle farming.

In the past, blood tests (like checking total cholesterol) could only show the results after a calf became malnourished. Therefore, this study aimed to find a "biomarker" (a biological sign in the body) to predict before weaning which calves are most likely to become malnourished in the future.

■ What did the study find?

The study revealed that the level of "cortisol" (a hormone related to stress) in a calf's saliva, measured two weeks before weaning, holds the key to predicting future malnutrition.

- Amazing Accuracy: The group of calves that suffered from malnutrition after weaning actually had significantly lower saliva cortisol levels before weaning (with a perfect accuracy score of AUC = 1.00).

- Why Saliva? Blood test results can easily change due to the stress of using needles. Saliva, however, shows the actual physical impact on the body more accurately. Plus, it has the great advantage of being completely painless for the calves!

■ How does this help?

This research brings great benefits to the livestock industry:

- Early Risk Detection: By identifying which calves might become malnourished before it even happens, farmers can take action early, such as adjusting their feed or giving them extra care.

- Healthier, Stronger Calves: Preventing malnutrition keeps calves healthy, which leads to steady growth and better meat quality in the future.

- Better Animal Welfare: Since farmers can check health using saliva instead of drawing blood, this is expected to be a "calf-friendly" care method that reduces stress on the animals.

[Journal]

Journal of Veterinary Medical Science

[Title of article]

Assessment of selected nutritional, bone metabolic and stress-related biomarkers

across the weaning transition in naturally suckled Japanese Black calves

[Authors]

Sueun KIM*, Haruka SUGIMOTO*, Koki ITAGAKI, Shinobu TSUCHIAKA, Shingo ISHIKAWA, Norio YAMAGISHI**

 * These authors contributed equally to this work

 ** Corresponding Author

[DOI]

 https://doi.org/10.1292/jvms.26-0006

[Contact Information]

For inquiries about this research, please contact: Norio Yamagishi, Professor, laboratory for Large Animal Clinical Medicine