Increasing the reproductive efficiency of dairy cattle -- getting thehighest possible number of cows pregnant in the same period of time -- hasalways been achallenge for this industry. Ohio State University specialistsare working to reverse this trend through the development of new reproductiontechniques and training that emphasizesproper management.
Currently,the national pregnancy rate for dairy cows is only 16 percent, while thebenchmark rate set by industry experts is 10 points higher, said GustavoSchuenemann, Ohio StateUniversity Extension's state dairy veterinarian. Ohio’srate is about the national average, he pointed out, so there's room forimprovement.
Lower pregnancyrates are an issue for the dairy industry because they translate into reducedherd growth and potential loss of profits, said Mike Day, an animal scientistwith theuniversity's Ohio Agricultural Research and Development Center(OARDC). "Dairy cows work hard every day," he said. "That makes it moredifficult for farmers to increasereproduction rates."
One waydairy farms can boost their reproduction efforts is the use of artificialinsemination (AI) and estrus (heat) synchronization techniques. Working withindustry partners, Dayand his research team have pioneered a new fixed-time AIprotocol -- known as "5-day CO-Synch + CIDR" -- that better synchronizes acow's estrus cycle so that AI can beadministered when cows are more fertile.
Arecommended practice within the beef cattle industry nationwide, this protocolhas been successfully tested on beef cows, resulting in 60 to 70 percent ofanimals getting pregnantwithin one day -- a 17.5-percent increase compared toindustry standards. Day and colleagues calculated that if 5-day CO-Synch + CIDRwere implemented with just 10 percent ofOhio's roughly 500,000 beef and dairycows, the total economic benefit would easily surpass $5 million in savings andincreased production.
Thisprotocol is now being studied in dairy heifers and cows by researchers at variouslocations across the country, Day said. The hope is that this approach willincrease fertility in dairycattle compared to current protocols, givingfarmers another tool to inch closer to their reproductive goals.
Whiletechnology is an important factor in boosting reproductive efficiency of dairycattle, it's not the solution by itself, according to OSU Extension'sSchuenemann.
"There'sno magic bullet," said Schuenemann, who develops and coordinatesresearch-based, practical training workshops for dairy producers, personnel andveterinariansthroughout Ohio. "There are many tools out there -- fromsynchronization protocols to heat detection to measuring cow activity -- butregardless of the tool a farmer may use,proactive management practices at thefarm level matter when it comes to reproduction."
One ofthe things Schuenemann emphasizes in his training programs is proper managementduring the transition period, which is three to four weeks prior to calving andapproximately one month post-calving. This, he said, is"key to reproductive success." Some of theissues that dairy farmers need to address during this crucial period includeavoiding overstocking of animals and commingling (mixing together) of maturecows with heifers; making sure cows get balanced food rations; and having areliable and well-trained group of workers who can properly handle calving andidentify and assist cows that experience difficult births as well as sick cowsafter calving.
Proactivemanagement also involves choosing the right tool or set of tools to maximizereproductive success.
"Thechoice of reproduction protocol needs to match the particular conditions ofeach farm, its resources, its objectives and the skill of its workers,"Schuenemann explained. "Alldairy farmers are unique, even if they are only amile apart from each other. So it's very important to assess human resources onthe farm. Some may adopt techniques that are moretime-sensitive and cost morein synchronization hormones, but which have the potential for higher pregnancyrates. Others may do better with heat detection and trying to takeadvantage ofnormal estrus.
"Youdon't want a farmer to fail because he picked a technique that doesn't work forhis conditions. Every farm is an integrated system; decisions made on one areaof the farm willhave an impact on other areas of the farm."
OARDC andOSU Extension are the research and outreach arms, respectively, of Ohio State'sCollege of Food, Agricultural, and Environmental Sciences.