Weekly pig prices dropped back down to 140.55p per kg during the week ending on New Year's Day, according to the latest available figures.
The EU-spec SPP was down 2.31p compared to a week earlier, and counteracts the 1p gain that was recorded in the previous week.
The SPP reflects the price of all standard pigs bought by GB processors in the previous 7-day week and is a simple average of all the prices paid in that week alone.
Analysing the figures, the AHDB said that even in 'normal' times, a slowdown in the pig market was typical in the post-Christmas period.
The estimated weekly clean pig throughput totalled 136,000 head, slightly lower than the equivalent week a year ago.
Carcase weights reached an average of 94.12kg, up almost 2kg on the week and again the highest on record.
Bethan Wilkins, AHDB red meat senior analyst, said: "Probe measurements have been a little volatile recently and increased again to an average of 11.8mm in the week; this was also recorded a few weeks ago and remains the highest probe measurement for the SPP sample since the series began.
"We clearly continue to see heavier, fatter pigs coming forward as a result of slaughter delays, now also compounded by the Christmas holidays."
Looking at the average price for just those pigs weighing 70-104.9kg, this was 143.85p/kg, only a drop of 1.24p on the week.
Ms Wilkins added: "Higher numbers of pigs outside normal contract specifications will have contributed to the drop in the SPP.
"Only 84% of the SPP sample fell within the 70-104.9kg bracket in the latest week, which compares to 87% the previous week and a longer-term average closer to 93%."
The EU-spec APP for the previous week ended 25 December followed the trend of the SPP in the same week and also rose.
At 148.85p/kg the price was over a penny higher than the previous week, and the gap between the two price series widened to 5.99p.
