Decades ago, cows gave far less milk and reproduction came easy. Today's cows produce high volumes of milk, but are still expected to calve back consistently. There was a downward trend for fertility until 2001, when a focus on reproductive health reversed that trend. Matt Lucy, University of Missouri, discussed this during the September Hoard's Dairyman webinar, "Getting them bred."

Lucy explained that new technology can often be taken for granted. Just two decades ago, the terms ovsynch, resynch, daughter pregnancy rate, sire conception rate, genomics, sexed semen, blood pregnancy tests and cloning were not on dairy producers' radar screens. But, how many of them are used today without appreciating the technology behind them?

"There is not one right way to manage your herd's reproduction," Lucy emphasized. Visual heat detection, tail chalk, synchronization programs and activity monitors all have their place. The key to their usefulness is the employee and facility options you have available. "What works great for your neighbor may not be the best solution for you," remarked Lucy.

A new technology that has not made it to U.S. yet is tracking progesterone levels in milk at each milking automatically. Graphs make hormone cycles very evident. It's easy to determine which cows are pregnant, and those that are not can be put back in the breeding pool quicker. It also clearly demonstrates irregularities, like cystic cows, which can be treated and reset to a normal cycle. Cows that are confirmed pregnant, but then due to unknown reasons lose an early pregnancy can quickly be spotted via their hormone graph.

Diagnosing pregnancies early can help producers identify open cows, which can enter a breeding protocol sooner. However, there is not a general consensus among the industry experts on this practice. Some caution that early diagnosis may endanger the pregnancy. However, "there are some cows that will suffer embryonic loss and there is nothing you could have done to prevent it," explained Lucy.

Lucy shared a few key points on dairy cattle reproduction:

• Breed cows that are in heat.
  
• Don't breed cows that aren't in heat. (fifteen percent of inseminations are to cows with a corpus luteum)
  
• Get your heat detection in order. (Have a plan that works for your operation.)
  
• Be aggressive in heat detection.
  
• Pregnancy check early if possible.
  
• When handling repeat breeders, consider giving GnRH at the time of breeding. Those cows might be late ovulators and your regular breeding protocols are not getting semen into the cow at the right time.
  
• If using monitors, breed 12 hours after maximum (heat) activity
  
• Seek input of veterinarians and reproductive professionals

Keeping these items in mind, 21-day pregnancy rates in the mid-20s (or higher) are achievable.

To learn more about resynch options, visit www.dcrcouncil.org