[Estimation of milk production in the nursing mare by labeling the body water of the foal].

This study determines a mare’s milk production by using a tracer method to estimate the water turnover of the nursing foal. This estimation of milk intake was cross-checked in 28 bottle-fed lambs, showing a high correlation with the true milk intake.

Methodology

The researchers employed a tracer methodology to make an estimation of the mare’s milk production. Here’s how they did it:

• A dose of deuterium oxide, a heavy form of water, was injected into the offspring’s bloodstream.
• The concentration of this isotope was then measured over time. As the isotope is passed from mother to offspring through milk consumption and then naturally excreted, the decrease in its concentration can provide an estimate of milk consumption.
• Using specific equations that also take into account the weight gain of the offspring, the researchers calculated the milk intake.

Reliability Check

To check the reliability of this method:

• The team used 28 bottle-fed lambs with known milk intake to validate this method.
• The correlation between the estimated intake using their method and the actual intake was as high as 0.98, indicating high accuracy.
• An error measure or discrepancy from the real values was also determined, which was around 5.6 percent on average and only 0.5 percent when taken on mean of 28 lambs.

Results & Implications

Using this technique:

• The researchers estimated the milk production of six brood mares during the first week of lactation, with results varying from 12 to 20 kilograms per day.
• Importantly, the method did not interfere with the mother-offspring relationship or the usual suckling conditions.
• This suggests the method can be advantageously applied during the onset of lactation in species where the offspring suckle frequently.