How Long are Calves Left with Dams after Birth?
How about leaving the calf with the dam for 2 hours? Six hours? Twelve hours or more?
A study of dairy farms in Ohio and Michigan included both conventional and organic producers. They reported their practice of separating calves from dams.
"The majority of conventional (64%, 279/439) producers reported separating the calf from the dam 30 minutes to 6 hours after birth.
More organic (34%, 56/166) than conventional (18%, 80/439) producers reported separation 6 to 12 hours after birth, and organic producers were more likely to agree that time before separation is beneficial." (p292)
If we do a little adding we conclude that among conventional dairies with 279 separating less than 6 hours and another 80 separation between 6 and 12 hours we have a total of 359 separating at 12 hours or less.
That means among the 439 conventional dairies there 80 farms (18%) remaining that routinely left calves with the dam for more than 12 hours.
On one hand, the advantage of early separation is reduced exposure to pathogens (for example, coliform bacteria, cryptosporidia parasites) being shed in high numbers by the dam.
On the other hand, folk knowledge suggests that the presence of the calf during the first 24 hours promotes lower rates of retained placenta and metritis.
In a review of scientific literature Dr. Leslie (University of Guelph) pointed out that the process of uterine recovery from birth is closely related to frequency of udder stimulation (either nursing or being milked).
Beef cows being suckled by their calves or dairy cows being milked 4 times daily have more rapid uterine recovery than dairy cows milked twice daily. Thus, the biological evidence shows that frequent oxytocin release in the days after calving is key to the processes of uterine health. Unless leaving the calf with the dam is connected to frequent suckling there appears to be no advantage to leaving the calf for an extended time with the dam (and maybe other adult animals).
What do I recommend to my clients? Do whatever you can to reduce pathogen exposure for newborn calves. On some dairies this means physically removing the calf from the dam's environment as soon as the calf is able to stand.
On other dairies dam access to the calf is given priority. Good calf health can still be accomplished without high pathogen exposure.
This means placing the calf in an environment where she cannot fall face-first into dirty bedding or lick the dam's dirty hair coat BUT the dam can still reach her to continue licking and stimulating respiration and healthful behaviors. Some farms put the calves a water tub in the calving pen while others use some kind of low gating to confine the calf while allowing access by the dam.
In my consulting practice, especially in Australia and Europe where it is a common practice to leave calve with dams for 24 hours or more, I have seen significant improvements in calf health associated with reducing cow:calf contact hours.
Pempek, J. and Others, "Dairy calf management - A Comparison of practices and producer attitudes among conventional and organic herds." Journal of Dairy Science, Supplement 2, 100:292. July 2017
Leslie, K., "The Events of Normal and Abnormal Postpartum Reproductive Endocrinology and Uterine Involution in Dairy Cows: A Review." Canadian Veterinary Journal 24:67-71