The critical spring mating period is under way on most of the country's dairy farms, but heavy rain, slips and floodwaters have closed key roads in the South Island, making it difficult to reach a number of flood-hit farms and get cows in-calf.

Despite the tough conditions, agritech and herd improvement co-operative LIC says it is using small planes and helicopters to make sure semen straws are still delivered to farmers on time.

National Artificial Breeding Manager David Hale said the co-op understood the importance of delivering semen to all farms on schedule, regardless of weather conditions.

"The dairy cow cycle takes roughly between 18-24 days. If insemination doesn't occur at the right time during that cycle, it means a three week wait until the cow is in heat again.


"This three week loss can have a number of negative flow-on effects for farmers, including the potential loss of three weeks' worth of milk supply and an impact on calving periods the following year".

A chopper touches down with semen supplies in the flood-affected area. Photo / Supplied
A chopper touches down with semen supplies in the flood-affected area. Photo / Supplied

A Cessna plane was used to successfully deliver around 3300 straws of semen between Timaru and Ashburton.

An additional 500 semen straws have been delivered via helicopter to affected farms on the West Coast. This helicopter delivery also included consumables needed by AB technicians to be able to do their jobs.

In a few cases, LIC's AB technicians have been able to access cut-off farms via tractor.

LIC took a similar approach during the Kaikoura earthquake, with semen straws successfully flown to affected farms.

It is a busy time of year, with the co-op dispatching and delivering around 5 million fresh semen straws and 1 million frozen semen straws from September through to Christmas.

LIC's 840 national artificial breeding technicians, supported by an additional 300 support staff, inseminate up to 100,000 cows each day during peak mating season. This equates to around 4.6 million inseminations performed by the co-op each spring.

Colin Corney, LIC's National Artificial Breeding Field Operations Manager, said affected farmers were doing an amazing job at looking out for each other and that there is a great support network.


"We are pleased to see farmers helping each other get through the wild weather. LIC will continue to deliver to flood-affected farms, unless it is too dangerous to do so".