Researchers have provided dairy producers with tools to improve reproductive performance in their dairy herds, yet the results continue to be less than desirable. Nationally, the 21-day pregnancy rate averages 13 to 14 percent; however, some herds are far above average. What do these herds do to attain success when many herds struggle with reproduction?

The herds
Eight herds were identified by reproductive management specialists in industry and academia as being top performers on reproductive measurements. These herds were in California, New Mexico, North Carolina, Texas, Virginia and Wisconsin. A three-page survey was used to query the herd manager regarding specific reproductive parameters, herd health practices, nutrition programs, reproductive programs, cow comfort, etc. that they used in attaining reproductive success. The reproductive performance in these herds was summarized, and an overview of the management used in the different herds to attain top performance was provided.

Reproductive programs
All eight herds had adopted some form of technology to insure that cows were bred in a timely manner. Although the techniques varied, in general they reduced the reliance on humans detecting estrus. Seven of the herds used presynchronization in combination with a synchronization program. Less than 1 percent of all animals received their first insemination after 100 days-in-milk in these herds.

Although these herds were synchronizing their cows for first insemination and resynchronizing the cows when they were determined not to be pregnant, six of the herds incorporated an estrus detection program; five of those used chalk and one visually observed for estrus six times daily as their estrus detection program.

Herd H initiated his synchronization program after attending a conference. After that conference, he moved his voluntary waiting period from 45 days-in-milk (DIM) to 65 DIM. His annualized pregnancy rate has climbed from 14 to 18 percent since initiating the synchronization program. Pedometry without a synchronization program was the technology adopted by the eighth herd. In that herd, 19 percent of all animals were first inseminated after 100 days-in-milk.

When asked to identify why they were successful, every herd identified key employees as crucial to their success. Each herd indicated that either trusted, long-term employees or family members were the A.I. technicians. Herd A indicated he wanted to hire someone that was willing to not be a “yes” man. When an employee had an idea, open discussion regarding the pros and cons would follow and changes resulted when it was “best for the animals.” Most of the dairies scheduled routine refresher courses.

Although the methodology varied between herds, each had developed a system to ensure compliance in their reproductive program. In those herds using synchronization programs, extra effort was used to insure that all cows received their scheduled treatments. In one of the herds, most of the treatments were given during the weekly veterinary exam. Herds C and E used sort gates associated with their parlor to sort cows out for treatment or insemination.

Cow care
Cow comfort was stressed in each herd. All of the herds had cow cooling; the type varied depending upon local climatic conditions. The cooling was regulated manually on some of the dairies, while others had automatic timers that varied with the daily temperature and humidity. Many of the holding pens had open sides to allow for maximum air flow. The herds with drylots had shades in their drylots.

The herds with freestall housing predominantly used sand bedding in their freestalls. The North Carolina herd had half sand beds and half mattresses but was in the process of removing the mattresses. Some of the herds had rubber matting on return lanes and where cows stood at the feedbunk. At one of the herds, cows stood in line for back scratchers. One herd stressed the importance of fly control to keep cows from bunching.

All the herds had close-up dry cow groups. Average time spent in this group varied from 14 to 21 days. There was also a super fresh group, where cows stayed from 14 to 30 days depending upon the herd.

Nutrition program
There were no magical ingredients in the rations of the dairies. All of the herds worked with a nutritionist to balance their rations. Every herd was feeding a silage-based total mixed ration (TMR). Generally, herds were fed corn silage and alfalfa (hay, greenchop or silage). Other crops used to make silage included sorghum, wheat, barley, rye and oats. Depending upon the herd, different types of fats were included in the rations. Some of the sources of fat included rumen-protected fats, tallow and whole cottonseed.

Over half of the herds manipulated dietary cation-anion difference (DCAD) in the close-up dry cow group. Heifers in these herds were not necessarily fed DCAD rations in the close-up period, if they were in a separate pen.

Health program
When asked about their vaccination programs all had customized their programs to their herd situation. All the herds were protecting their lactating herd against respiratory diseases using an IBR-BVD-PI3 vaccine. Five-way leptosporosis vaccines were used in all of the herds. In addition, three of the herds were vaccinating for Leptosporosis hardjo bovis.

Although many states are now classified as brucellosis-free, all but one of the herds vaccinated their heifers for brucellosis. The herd that did not vaccinate for brucellosis indicated that when they stopped vaccinating for brucellosis they initiated a program to ear notch heifers to check for calves persistently infected with BVD (BVD-PI). They have found several infected animals and immediately cull them.

Herd G had tested his bulk tank to screen the lactating herd for BVD-PI animals. When a positive string test was found, all the animals were ear notched in that string and one animal was identified as being BVD-PI. This animal had just been culled when the herd was visited.

Reproductive program opportunities
Although these herds were interviewed because of outstanding herd reproductive performance, it doesn’t mean they don’t have challenges. Three of the herds identified abortions as the greatest challenge in their reproductive program. No other item was identified by more than one herd. Herd B indicated heat stress was a major problem; however, the steps they had taken to add additional shades and cooling had reduced significantly the magnitude of the problem.

Problem breeders (herd C), detection of estrus to insure a timely second service after the timed A.I. (herd D), older cows (herd H) and just getting cows pregnant (herd F) were the other problems identified.

To identify the most valuable part of their reproductive program, producers were asked what one thing they would not change. Herd A indicated their personnel. The synchronization program was identified by herds B, D, E, F and G. Due to the importance of the pedometers identifying cows in estrus, herd C selected the pedometers as what they wouldn’t change. Herd H indicated he wouldn’t change the voluntary waiting period he was currently using.

All the herds were satisfied generally with their current programs and did not intend to make major changes to their reproductive program in the next three months. Most indicated if a recommendation came along that facilitated greater success and was practical on their farm, they would consider whether to make the change. One of the herds planned on evaluating their estrus detection program; another planned to attempt some breeding based on pedometer readings. Herd G planned to alter his program slightly by changing his voluntary waiting period and tweaking his synchronization program.

Reproductive management tips
Each of the herd representatives was asked to share reproductive management tips with other producers. In general, these tips emphasized compliance, willingness to change, employee communications and cow care. The bottom line to the success of these eight herds was attention to detail throughout every aspect of the dairy, from nutrition to health to employee management. They have identified key consultants to help them customize reproductive programs to fit their individual situations and then have insured those programs were implemented by a trained, motivated workforce. Personnel were identified frequently as the key to the herd’s success.

Conclusions
Although these herds were not managed identically there were several factors that were shared.

• All the herds had adopted technology to overcome estrus detection program challenges.

• Trusted, long-term employees or family members were the A.I. technicians.

• Most of the dairies scheduled routine A.I. refresher courses.

• Each had developed a system to ensure compliance in their reproductive program.

• Cow comfort was stressed in each herd – cooling, sand bedding, etc.

• All the herds had close-up dry cow and super fresh groups.

• Over half of the herds manipulated DCAD in the close-up dry cow group.

• All had vaccination programs customized to their herd situation, with half having a program to identify BVD-PI positive animals.

• All the herds had silage-based TMR rations; however, there was no magic ingredient.

• Personnel were identified as one of the keys to the herd’s success. PD

References omitted but are available upon request at editor@progressivedairy.com

—Excerpts from 2006 Dairy Cattle Reproductive Council Annual Meeting and Convention Proceedings

Ellen R. Jordan, Ph.D.
Texas A&M University