How Do I Get Better Repro Rates in My Dairy Herd?: DHI Herd Data Review

July 8, 2020

“How Do I Get Better Repro Rates in My Dairy Herd?”: DHI Herd Data Review – Dr. Rob Swackhammer & Megan Jamieson (DVM student, Class of 2022)

Thanks to our veterinary student Megan Jamieson for entering and helping to analyze the data.  We took the information from the producers’ 2019 Lactanet annual reports.  While this does leave out a few herds we believe it is representative of the overall trends we see.

Clinic Comparison: Herds with Consistent Herd Health Visits vs. Herds with Inconsistent Herd Health Visits


  •  Herds with consistent herd health visits = a herd that participates in a routine herd health program with a

veterinarian (2-4 times a month)

  • Herds with inconsistent herd health visits = a herd that inconsistently participates in a herd health program with

a veterinarian (0 to <2 times per month)

Data Summary – Cows:

Consistent HH AVERAGE Inconsistent HH


Pregnancy rate %   17.00 13.55 +3.55%
Insemination rate %   46.09 40.27 +5.82
Conception rate %  38.91 34.09 +4.82
DIM at 1st breeding 79.14 86.73 Bred 7.59 days sooner
% pregnancy by 150 DIM  49.91 39.45 +10.46%
Times bred 2.00 1.95 0.05 more breedings
% 1st service conception  37.68 34.73 +2.95
Days open  104.21 113.25 9.04 less days open
Calving Interval (months) 13.33 14.04 0.71 less months between calvings


Data Summary – Heifers: 

Consistent HH AVERAGE Inconsistent HH


Age at 1st calving (months)  24.45 26.14 Calving 1.69 months earlier
Age at 1st breeding (months)  14.19 16.10 Bred 1.91 months earlier
Age at conception (months)  14.74 17.40 Pregnant 2.66 months earlier
% heifers pregnant by 15 months 45.39 21.88 23.51% more
Times bred 1.87 1.93 Bred 0.06 times less
% 1st service conception  55.22 51.13 +4.09%


*(Numerical differences were found between the 2 groups however the differences between the 2 groups were not found to be statistically significant. We believe this is mostly due to inadequate numbers of herds in this evaluation.  We also believe the trend is plausible and follows what we observe in practice)


Although we cannot magically make repro rates better by walking on a farm, we believe part of the recipe for success in reproductive performance on dairy farms is to schedule consistent and timely herd health visits.  By making it routine, fresh cows get examined quickly (30 DIM) to ensure their reproductive tract is healthy and ready to conceive.  Bred cows get confirmed pregnant or diagnosed open in a more timely manner and thus rebred quickly.  Problem cows get identified early and a suitable intervention applied to improve the chances of getting pregnant and thereby staying in the herd.

We believe there are many other benefits to having a veterinarian on the farm on a routine basis.  Creating a close association with a trusted advisor allows important conversations to occur frequently.

In conclusion, we were very pleased to see the overall positive results of having consistent and timely herd health visits.  Thank you to all the clients that give us the opportunity to work with you on your farms.  We look forward to helping you achieve your goals for your farm.

If you have any questions on these or other topics, please do not hesitate to contact one of our Veterinarians.

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7643 ON-6, Arthur, ON N0G 1A0
1139 Settlers Rd., Sheffield ON L0R 1Z0

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