With the growth of dairy beef genetics across New Zealand and a keen uptake among farmers, we’re seeing a strategic shift towards using quality dairy-beef genetics through AI before releasing natural mating bulls.
Traditional dairy mating strategies follow a familiar pattern: high Breeding Worth (BW) dairy sires for the first four to six weeks for replacements, then natural mating bulls to sweep up the remaining cows and ensure cows are in-calf. The calves from this tail-end mating period are historically low-value non-replacement calves or mixed-breed animals with uncertain genetics – not the kind of animals that play into your breeding strategy!
The value proposition
Many dairy farmers run natural mating bulls with cows that fail to get cows in-calf during the mating period. While it’s convenient, it’s an approach that produces calves with unknown genetic merit, that are no good for milking, typically fetch lower prices and grow inconsistently. According to research from the Beef + Lamb New Zealand Dairy Beef Integration Programme, dairy beef calves sired by proven beef bulls are worth approximately $70 more than mixed or straight-bred dairy calves.
Capture higher-value calves from cows that might otherwise be mated to bulls of unknown merit with a one to two-week round of AB with proven dairy beef sires before releasing the natural mating bulls . The calves born from this strategic AB period are also going to arrive earlier in the calving season compared to bull-mated animals, condensing calving spread.
Selecting the right beef genetics
Calving ease is a prime factor when choosing quality dairy beef genetics for this pre-bull AB period. Especially important if your herd is composed of smaller-stature breeds like Jerseys or a Jersey-cross. We suggest selecting bulls with low birth weight EBVs and proven calving ease data to maintain cow productivity and fertility. Gestation length also matters for maintaining tight calving patterns. Beef breeds typically have longer gestation periods than dairy cattle, averaging around 283 days. Choosing beef sires with shorter gestation breeding values helps keep your calving pattern compact, with some proven short-gestation genetics reducing gestation periods by 8-10 days compared to breed averages.
According to DairyNZ, sire selection matters more than breed selection when it comes to birth weights and carcass performance. Look for bulls with strong EBVs for 200-day weight, 400-day weight, eye muscle area, and intramuscular fat. These traits translate directly to faster-finishing animals that command premium prices.
Practical implementation
Most farmers using this AB-first strategy dedicate one to two weeks of AB with dairy beef semen before introducing natural mating bulls. This timeframe provides sufficient opportunity to catch cows cycling without lengthening your overall mating period.
Identify which cows will receive dairy beef genetics: some farmers target all non-pregnant cows after the main dairy replacement AB period, while others select lower BW cows that won’t be kept as replacement dams.
Record-keeping during this period becomes essential. Mark or identify cows mated to beef AB so you can easily identify dairy-beef cross calves at birth. Heat detection during this period follows standard practices, with the key difference being having beef semen available and ensuring your AB tech knows which cows receive which semen.
Accessing quality dairy beef genetics
World Wide Sires NZ provides comprehensive access to proven dairy beef genetics suitable for pre-bull AB strategies. Their catalogue includes multiple dairy beef breeds with full EBV data, from traditional Angus and Hereford to Charolais, Belgian Blue, and Speckle Park. Choose polled bulls, eliminating dehorning costs and welfare concerns.
World Wide Sires’ breeding consultants understand the timing challenges of New Zealand’s seasonal system and can recommend bulls that deliver easy calving, appropriate gestation length, and strong growth performance. They can help calculate semen requirements for your pre-bull AB period and suggest breed options that suit your target markets.
Financial returns
The economics look favorable for most operations. For a 400-cow dairy farm with 100 cows still cycling after the main replacement AB period, a two-week beef AB mating program might achieve 40-50 conceptions. Those beef-cross calves represent $2,800 to $3,500 in additional calf value compared to bull-mated dairy calves.
The shift from random bull-mating to strategic beef AI before bull release represents a practical way to add value from every cow in the herd.