The measurement of volatile organic compounds in faeces of piglets as a tool to assess gastrointestinal functionality

Highlights

• Monitoring of gastrointestinal functionality is important for animal health.

• Measuring the odours emanating from pig stool may provide a means.

• Faecal volatiles were measured using two forms of Ion Mobility Spectrometry.

• Results indicate we can separate pigs being fed different diets.

• We can also link faecal score to volatile readings.

There is an increasing interest in developing innovative means to monitor animal health through precision farming. As part of this drive, we have targeted digestive health and in particular the microbiota. In this study, we investigated the effect of different dietary interventions in piglets, feeding these piglets with one of two different feeds (high protein and low protein). We then evaluated its effects by measuring the volatile organic compounds (VOC) that emanated from these faecal samples using various forms of Ion Mobility Spectrometry. Piglets were monitored for 19 days, with faecal samples collected on days 6, 12 and 19, providing a total of 69 samples. The statistical analysis attempted to separate the samples using either dietary intervention or faecal score. First, the faecal score was investigated using a value based on a visual faecal scoring system, from 0 to 3, with 0 being normal and 3 having diarrhoea. Then the VOCs were analysed in regard to dietary intervention (high vs low protein). Results indicated that our approach was able to separate the dietary intervention (area under the curve (AUC) 0.81) using VOC data. Furthermore, we were able to separate samples based on faecal score (AUC between 0.71 and 1, with six different comparisons undertaken). We believe that faeces volatiles hold potential as a future means to monitor animal health.