Breeding Bulls for LIC

Dairy farmers Bruce and Bronwyn Jensen produce premier bulls with a healthy strike rate of around 3 bull calves being picked up by top semen supplier LIC every year from their farm near Kimbolton. Their herd has produced top premiere sires Greenmile Milan and Greenmile T-Rex.

The Jensens’ Greenmile Farms cover 300 hectares in North Manawatu in a System One/System Two operation. Bruce explains they just grow good clover, apply a bit of potassium to help clover growth and farm to the conditions. They milk 730 cows twice a day. When asked if he plans to go to once a day milking Bruce says, “No way, production’s too good.”

Breeding consists of five weeks of AI followed by three weeks of bulls “in with the girls”, then 2 weeks of short gestation AI to finish. Bruce says short gestation semen that can reduce a pregancy by around 10 days is becoming more and more sought after.

Bruce needs around 1,000 straws (of semen) a season for AI and he keeps a careful eye on sire rankings in Denmark and Australia too.

Malcolm Ellis is LIC’s General Manager of New Zealand markets. He is an experienced dairy farmer himself and was breeding bulls when approached about a roll as a Bull Acquisition Manager for LIC. He worked closely with Bruce in that role, and now has an oversight of the broader markets in the GM role.

Every year as part of the industry guest for Genetichain, LIC identifies thousands of elite cows from the National database. This elite group is narrowed down before inspection and selection as potential contract mating cows. Production capability, physical traits and strong cow “families” are key selection criteria. 

One such group of cows from an outstanding family was identified on the Jensen’s farm. LIC has been working with Bruce and this family for the best part of 10 years. Such cow families are ‘gold nuggets’ as Malcolm Ellis puts it.

When first approached, Bruce made the decision to do an embryo transfer. The cow was flushed at 7 days to generate bull calves for LIC. From the first embryo transfer one bull and five heifer calves became the basis of the superstar Hilda brand at LIC. “It snowballed from there”, say’s Bruce. Malcolm adds, “I’ve no hesitation to say the Hilda brand is producing some of our top sires”.

So how do you pick a good bull calf – how do you predict a good sire with high producing offspring?

In the old days Bruce said he was looking for a quiet temperment – a cow that settled quickly; presented a good udder with downward pointing teats; had a big gut to eat lots of grass; with top fertility and excellent milk production stats.

Now, in this brave new world of genomics, a DNA test is the key. LIC takes DNA from a number of possible bull calves when they’re 2 weeks old. Bruce reckons he usually has 20-30 tested a year. They’re looking for a whole bunch of gene markers and around three calves will be selected from the orignal pool and they’ll be “gone by Christmas”.

Malcolm Ellis says in the early days of the DNA technology (2008/2009) when the exciting new global technology was in its infancy, there was a high weighting and dependence on the genomic profile with respect to bull selection. Today the balance of selection is combining the ‘magic of the DNA’ alongside the strength of the identified cow families that have proved their worth over generations.

Malcolm stresses that decisions are now based on the most efficient cow – not the heifer with the highest milk production stats as, “the industry needs efficient converters of pasture to milk”. Liveweight efficiency is key to that equation.

Bruce says in order to keep his edge with producing good sires, good record keeping and herd testing is important to track each individual cow – and is a requirement of farmers looking to submit bull calves to LIC.

Malcolm is passionate about his work, stressing that “breeding is a long game” and farmers have to be prepared for the future. For example, with increasing pressure on the scale of herds farmers are going to want only the very best, top producing cows.