Age at first calving in dairy cows: which months do you aim for to maximise productivity?

  • Mike Steele Inspire Cattle Solutions



Open Access Logo



PICO question

In dairy cattle, which months should producers target age at first calving in order to maximise milk yield, minimize risk of non-voluntary culling and optimize fertility?


Clinical bottom line

Category of research question


The number and type of study designs reviewed

Seventeen papers were critically reviewed: 15 sets of case series, one review of case series and cohort studies and one randomised control trial, summarising over 2.4 million individual cow records

Strength of evidence


Outcomes reported

An optimum range of age at first calving (AFC) on dairy farms appears to be 22–25 months inclusive. Lower or higher than this figure can bring lower first lactation 305 day and lifetime milk yields, lower fertility and lower chances of surviving to a second lactation. Achieving an AFC of 22–25 months can bring the highest economic return to dairies


Age at first calving is a useful and key performance parameter to measure in dairy cattle. Achieving a range of 22–25 months at first calving can help to optimise both long term milk yield, fertility and longevity within the herd


How to apply this evidence in practice

The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources.

Knowledge Summaries are a resource to help reinforce or inform decision making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.


Open Access Peer Reviewed

Author Biography

Mike Steele, Inspire Cattle Solutions

Mike is an independent dairy consultant to the dairy industry. His company, Inspire Cattle Solutions serves to increase in-depth knowledge of dairy farming practices and provide improvement projects on farms, in research and development and in education.


Adamczyk, K., Makulska, J., Jagusiak, W. & Węglarz, A. 2017. Associations between strain, herd size, age at first calving, culling reason and lifetime performance characteristics in Holstein-Friesian cows. Animal 11 (2): 327–334. DOI:

Banos, G., Brotherstone, S. & Coffey, M.P. 2007. Prenatal maternal effects on body condition score, female fertility, and milk yield of dairy cows. Journal of Dairy Science 90 (7): 3490–3499. DOI:

Berry, D.P. & Cromie, A.R. 2009. Associations between age at first calving and subsequent performance in Irish spring calving Holstein–Friesian dairy cows. Livestock Science 123 (1): 44–54. DOI:

Bond, G.B., von Keyserlingk, M.A., Chapinal, N., Pajor, E.A. & Weary, D.M. 2015. Among farm variation in heifer BW gains. Animal 9 (11): 1884–1887. DOI:

Changhee, D., Nidarshani, W., Kwanghyun, C., Yunho, C., Taejeong, C., Byungho, P. & Donghee, L. 2013. The Effect of Age at First Calving and Calving Interval on Productive Life and Lifetime Profit in Korean Holstein. Asian Autralasian Journal of Animal Science 26 (11): 1511–1517. DOI:

Chester-Jones, H., Heins, B.J., Ziegler, D., Schimek, D., Schuling, S., Ziegler, B., de Ondarza, B., Sniffen, C.J. & Broadwater, N. 2017. Relationships between early-life growth, intake, and birth season with first-lactation performance of Holstein dairy cows. Journal of Dairy Science 100 (5): 3697–3704. DOI:

Davis Rincker, L.E., Vandehaar, M.J., Wolf, C.A., Liesman, J.S., Chapin, L.T. & Weber Nielsen, M.S. 2011. Effect of intensified feeding of heifer calves on growth, pubertal age, calving age, milk yield, and economics. Journal of Dairy Science 94 (7): 3554–3567. DOI:

Eastham, N.T., Coates, A., Cripps, P., Richardson, H., Smith, R. & Oikonomou, G. 2018. Associations between age at first calving and subsequent lactation performance in UK Holstein and Holstein-Friesian dairy cows. PlosOne 13 (6): e0197764. DOI:

Elahi Torshizi, M. 2016. Effects of season and age at first calving on genetic and phenotypic characteristics of lactation curve parameters in Holstein cows. Journal of Animal Science and Technology 58 (8): doi: 10.1186/s40781-016-0089-1. DOI:

Ettema, J.F. & Santos, J.E. 2004. Impact of age at calving on lactation, reproduction, health, and income in first-parity Holsteins on commercial farms. Journal of Dairy Science 87 (8): 2730–2742. DOI:

Haworth, G.M., Tranter, W.P., Chuck, J.N., Cheng, Z. & Wathes, D.C. 2008. Relationships between age at first calving and first lactation milk yield, and lifetime productivity and longevity in dairy cows. Veterinary Record 162 (20): 643–647. DOI:

Krpalkova, L., Cabrera, V.E., Kvapilik, J., Burdych, J. & Crump, P. 2014. Associations between age at first calving, rearing average daily weight gain, herd milk yield and dairy herd production, reproduction, and profitability. Journal of Dairy Science 97 (10): 6573–6582. DOI:

MacDonald, K.A., Penno, J.W., Bryant, A.M. & Roche, J.R. 2005. Effect of feeding level pre- and post-puberty and body weight at first calving on growth, milk production, and fertility in grazing dairy cows. Journal of Dairy Science 88 (9): 3363–3375. DOI:

Nilforooshan, M.A. & Edriss, M.A. 2004. Effect of age at first calving on some productive and longevity traits in Iranian Holsteins of the Isfahan province. Journal of Dairy Science 87 (7): 2130–2135. DOI:

Pirlo, G., Miglior, F. & Speroni, M. 2011. Effect of age at first calving on production traits and on difference between milk yield returns and rearing costs in Italian Holsteins. Journal of Dairy Science 83 (3): 603–608. DOI:

Ruiz-Sanchez, R., Blake, R.W., Castro-Gamez, H.M.A., Sanchez, F., Montaldo, H.H. & Castillo-Juarez, H. 2007. Changes in the Association Between Milk Yield and Age at First Calving in Holstein Cows with Herd Environment Level for Milk Yield. Journal of Dairy Science 90: 4830–4837. DOI:

Sadeghi-Sefidmazgi, A., Moradi-Shahrbabak, M., Nejati-Javaremi, A., Miraei-Ashtiani, S.R. & Amer, P.R. 2012. Breeding objectives for Holstein dairy cattle in Iran. Journal of Dairy Science 95: 3406–3418. DOI:

Storli, K.S., Klemetsdal, G., Volden, H. & Salte, R. 2017. The relationship between Norwegian Red heifer growth and their first-lactation test-day milk yield: A field study. Journal of Dairy Science 100 (9): 7602–7612. DOI:

Wathes, D.C., Pollot, G.E., Johnson, K.F., Richardson, H. & Cooke, J.S. 2014. Heifer fertility and carry over consequences for life time production in dairy and beef cattle. Animal 8 (1): 91–104. DOI:

Vol. 5 No. 1 (2020): The first issue of 2020

Section: Knowledge Summaries

Categories :  Small Animal  /  Dogs  /  Cats  /  Rabbits  /  Production Animal  /  Cattle  /  Sheep  /  Pig  /  Equine  /  Exotics  /