Dairy farmers are being encouraged to consider using genetically superior beef bulls across their herds this spring to help create greater value along the value chain.

This is based on a recent report summarising the findings of the Beef + Lamb New Zealand Genetics’ Dairy Beef Progeny Trial.

Written by farm consultant Bob Thomson, the report summarises the findings of a whole-farm modelling process, where the progeny of the highest ranked beef bulls from the Dairy Beef Progeny Trial (DBPT) were compared with the progeny of average bulls.

These showed a 15% growth advantage at 400 and 600-days compared to the average bulls. This would improve gross margin returns by between $172 and $211/ha and improve feed conversion efficiency by 10%. This in turn would reduce greenhouse gas emissions.

The modelling demonstrated that when the top 10-15% DBPT bulls for marbling (intramuscular fat) were compared with the average DBPT bulls there was a 20% improvement. This correlated with an increase in the strike rate with beef quality supply programmes, although with a price premium of 30c/kg carcase weight, this only increased the gross margin by another $22/ha.

The modelling also compared one and two winter finishing policies and highlighted clear advantages and disadvantages to both. The ranking of DBPT bulls did not change between the two policies. Compared to the two-winter, the one-winter system occupied one-third less land area with 15% more feed conversion efficiencies.

The disadvantage was in lighter carcase weights (160-220kg CW) when processed between November and February. These weights were outside targeted beef grading and associated payment schedules.

Building a connection between dairy farmer and finisher

The report noted a disconnect between dairy farmers and beef finishers and the advantages for both parties to address this. Working with a dairy farmer who is investing in superior beef genetics gives the finisher the opportunity to benefit from significantly improved growth rates and carcase attributes.

The report states that this disconnect has come about because finishers tend to prefer to buy dairy-beef spring-born weaners in autumn rather than rear them over summer. In drought years, when this is most apparent, there is little difference in the price between autumn and spring calves.

Dairy farmers producing high quality calves often felt frustrated with variable and inconsistent demand from beef finishers irrespective of whether they are four to five-day old weaners or 100-kilogram weaners.

“Once the calves leave the dairy farm the connection back to their genetic merit is usually lost. This leaves the beef finisher to judge calves on their coat colour and condition,” Thomson says.

Bobby calf policies- a reason to change

Dairy farmers will likely be faced with a no bobby calf kill policy within the next few years and will either have to produce calves that have value as a beef finishing animal or reduce cow numbers to accommodate the rearing of surplus calves.

“Either way, the value of the surplus calves can be raised significantly by dairy farmers utilising high genetic merit beef bulls over the dairy cows which are not required to generate their dairy replacements,” he says.

The high genetic merit beef bulls identified in the DBPT are proven performers and their genetics are only available in commercial quantities through artificial insemination.

Analysis has shown that the actual cost of beef AI in dairy herds is slightly less than natural mating and generated many more advantages. These included shorter gestation length, proven easy calving and calves which will grow faster and to heavier weights for finishers.

There was also better biosecurity and work safety associated with AI.

Dairy beef progeny test

The purpose of the DBPT, which began in 2015, was to identify high genetic merit beef bulls that would benefit both dairy and beef farmers. Over the course of the programme, detailed and comprehensive phenotypic data has and continues to be collected, analysed and reported for a range of traits including gestation length, calving ease, growth rates, carcase weight and carcase quality.

The trial includes a number of beef breeds with around 20 new bulls being progeny tested every year. The most up-to-date report showed the top five bulls ranked on carcase weight represented by five different breeds.

“These results highlight the fact that between breed analysis is important and no one breed dominates the beef breeding opportunities for NZ farmers.”

All of the cattle in the progeny test are born on Pāmu’s Renown farm at Wairakei Estate and reared and finished under commercial conditions at Pāmu’s Orakonui farm, also at Wairakei Estate.

The weights of all the calves are recorded at 200, 400 and 600 days.

Calves are run in four groups after weaning (two groups of heifers and two groups of steers) for finishing and are DNA-verified to Progeny Test sires.

In 2019, B+LNZ entered into partnership with LIC (which helps fund the test) to ensure dairy farmers have access to the best bulls coming through the progeny test.