Predicting cattle disease ahead of time – through blood tests

MicroRNA levels in the blood could be used to predict the future health and productivity of dairy cattle, British scientists have discovered in recent research.

In UK dairy herds, up to a third of cows are affected by disease or reproductive failure and need to be culled before their time, putting significant costs to farmers and raises animal welfare issues.

A study by scientists at The Roslin Institute and Scotland’s Rural College (SRUC) showed that the blood levels of certain microRNAs change dramatically during early life in cows.

In addition, importantly, some microRNAs are closely associated with the incidence of diseases such as lameness and mastitis, as well as with milk production in mature cows.

MicroRNAs are small molecules produced by all body tissues, which play important regulatory roles in animals and plants, according to the Roslin Institute.

MicroRNA levels can be readily quantified in blood using standard laboratory procedures and can be used to examine changes in the function of specific body tissues – a feature that is already being exploited for disease diagnosis in humans.

One of the authors of the study at The Roslin Institute, Dr. Xavier Donadeu, commented on the findings.

He said: “As we have already shown in previous studies, these results show that microRNAs may be very useful as diagnostic tools in dairy cows and potentially other livestock species.

Specifically, we think that microRNAs could allow for selection early on of the most promising animals in a herd in order to maximise productivity and animal well-being.

This work has been supported by SRUC funds awarded to Prof. Georgios Banos and Dr Xavier Donadeu. According to the Roslin Institute, the results are published in the journal Scientific Reports.