Extension column: Getting cows bred with artificial insemination
for Tri-State Livestock News
Fortunately moisture has fallen on most of the high plains area to at least get the cool season grass started. Although certainly a brighter picture than we saw a month ago we will need to continue to get more moisture to provide continued growth and production. The green grass has been very tempting to turn out on however the range management specialists are urging caution in turning out too soon at a high stocking rate unless pasture rotation is planned. It seems to me that turnout date depends a lot on amount of old grass, which in many regions is very little, and stocking rate. If stocking rate is low enough to not take a high proportion of grass early in the grazing season then the risk is much lower of running out of grass early or those on a good rotation can allow the early grazed pasture to recover. Having said all this I realize that where high priced harvested feeds and supplements are in short supply and when the rain is falling it is very tempting to open the gate.
Bull turnout time is either here or coming very soon for most spring calving herds. Hopefully they have been or will be semen tested before turn out, especially bulls that are being turned out by themselves in single sire pastures.
The commercial beef industry continues to use artificial insemination (AI) at a very low rate compared to the beef seedstock producers and the dairy industry. Labor continues to be the main reason ranchers choose to rely on natural service especially in the mature cow herd which is often bred after the cows go to grass especially for those that have chose to calve later in the spring. It has been some time since Sandy Johnson of Kansas State did some calculations on the economics of AI but at that time the apparent economic return was positive for many scenarios however I still don’t see a ground swell of growth in AI. Again, I believe this is largely due to lack of and/or cost of labor and facilities.
Dr. Rick Funston, reproductive physiologist at the University of Nebraska, continues to look for ways to make AI more economical for ranchers by either lowering inputs or increasing the number of calves born from AI sires.
One approach he has taken to lower input of labor and product cost that some ranchers use with good results is to turn the bulls in with the cows for 5 days, give every cow a shot of prostaglandin five days later and then breed on estrus detection. This still requires heat detection however he has worked on some protocols to use both heat detection and timed AI. He also reports that several ranchers have used this program with natural service and has been able to get a significant higher number of calves born in the first 21 days resulting in a heavier weaning weight of uniform calves.
He recently conducted a study with May-calving cows and reported the results in the 2013 Nebraska Beef Cattle Report (beef.unl.edu/web/beef/nebeefreport 2013) where he used high inputs in a synchrony program with the objective to get a higher percent of AI calves.
He basically compared the CO-Synch program with or without a CIDR. The Co-Synch program basically involves giving GnRH injection, then seven days later give a prostaglandin injection and then time breed with another GnRH injection 48 hours after the prostaglandin. In Dr. Funston’s study he used a similar program only used a CIDR the first seven days and time bred at 60 hours after removing the CIDR. This is a high input program in both cost of product plus three times through the alley (chute).
The AI success for both programs were relatively low – 32 percent for Co-Synch and 54 percent for the Co-Synch plus CIDR, however overall 14 percent more calves (90 percent versus 76 percent) were born in the first 21 days. It appears from this data that if one chooses to use the Co-Synch program the added cost of the CIDR would be economical plus waiting until 60 hours for timed AI.
In my opinion research needs to continue to find a more cost effective way – both cost of products and labor – to get a high percentage of cows bred AI or AI will continue to be utilized by a limited number of commercial cow-calf producers.
Keep the rains coming.