Staff at 12 meat plants run by Silver Fern Farms worked on Good Friday and Easter Monday to try to catch up with a serious backlog of animals needing to be processed.
The company won't give any numbers because of commercial confidentiality but says a dent was made in the logjam of stock at hardpressed processing plants.
The problem arose even before the Covid-19 crisis, when drought killed off grass growth on many New Zealand paddocks, leaving little feed available for livestock.
To solve this problem, farmers sent their stock to the works early, creating a backlog of stock in waiting yards.
The arrival of Covid made the problem worse, because workers were spread more widely on killing chains, cutting production rates of beef by 30 percent and sheep by 50 percent.
To help solve this problem, Silver Fern Farms put staff on duty on Good Friday and Easter Monday.
The chief executive of Silver Fern Farms, Simon Limmer, said other things were being done to lift the levels of processing.
They included operating daily overtime and Saturday kills for the foreseeable future, retaining staff who are currently surplus to processing requirements, and investigating the option of putting on additional chains in some plants.
Other means of dealing with the problem include deferring planned maintenance and shutdowns, and possibly moving stock around different processing plants.
Limmer said the current waiting time for both sheep and beef was two to three weeks in the North Island and four to six weeks in the South Island.
He also said attention would be given to animal welfare.
Silver Fern's big rival, the Alliance Group, took a different path and chose not to work staff over the Easter break.
Its chief executive, David Surveyor, said it was important to give staff some well deserved time off.
"Our focus over the past fortnight has been on keeping Alliance Group's plants running as smoothly as possible despite the challenging circumstances," Surveyor said.
"We are lifting beef and ovine processing capacity this week and there will be some further opportunities to lift capacity as we get used to new configurations.
"Our goal is ensuring the safety of our people, processing our farmers' livestock and supporting our communities and we will look for further gains in our operation."