However, the researchers, writing in Livestock Science,​ said the effect on gut health and on diarrhea incidence needs to be investigated to evaluate whether delayed weaning is an effective alternative to antibiotics and medical zinc.

The authors wanted to investigate the impact of weaning age and/or supplemental liquid feed in the farrowing pen on pre- and post-weaning feed intake.

Weaning challenges

Piglets, they outlined, are subjected to an abrupt feed change at weaning from milk to solid feed. This frequently results in a reduced feed intake, reduced growth and diarrhea. To treat diarrhea, antibiotics or medical zinc is widely used.

High use of antibiotics is, in turn, associated with high risk of developing antimicrobial resistance (Gresse et al., 2017), and since the use of medical zinc will be banned in the EU from 2022 (Directive 2001/82/EC 2017), the hunt is on for alternatives to prevent or reduce post-weaning diarrhea (PWD), said the researchers.  

The common weaning practice is to remove piglets from the sow between 18 and 35 days of age, depending on the country (Edwards et al., 2020), they commented.

Within the EU, the minimum age is 28 days while 21 days is allowed in cases where piglets are weaned in batches into cleaned and sectioned pens.

The researchers noted that with increasing litter size, the weaning age tends to be driven towards the lower age due to the use of nurse sows and space limitations in the farrowing unit (Baxter et al., 2020). “For example, the mean weaning age in Denmark is reported to be 25 days of age in average (Udesen and Christiansen, 2017).”