“Removing calves from the cows for 48 hours has shown to be successful in starting cows cycling after calving,” says Chris Zumbrunnen, regional extension livestock specialist in Milan, Mo. “This period of calf removal helps to reduce the suppressive effect nursing has on the hormonal system of the cow.”
Independent beef producers and researchers at the University of Missouri Forage Systems Research Center in Linneus, Missouri, studied 300 first-calf heifers and 150 young cows, located on six farms, to determine the effect of short-term calf removal on the calving interval of the dam.
The 450 females were divided into three treatment groups to study the effects of single and multiple periods of calf removal. Group one, the control group, had no calf removal. The calves in the second group were removed from their mothers for 48 hours starting on the day the bulls where turned out. In the third group, calves were removed for 48 hours on the day bulls were turned out and then two weeks later calves were removed for another 48 hours.
The date of calving in the spring of 1996 and 1997 was recorded for each female to determine the calving interval for each female. Records were kept on all calf heath problems and treatments during removal and several days following. Weaning weights were also collected on all calves to measure any impact calf removal had on growth.
Average calving interval for each of the three groups
No calf removal: 384 days
1 time calf removal: 373 days
2 time calf removal: 368 days
The average calving interval was reduced by 11 days when the calves were removed from their dams for one 48 hour period and by an additional 5 days when the calves were removed twice. Using the data from this study, calving an average of 11 days earlier would result in an additional 22 pounds weaned per calf (11 days x 2.0 lbs./day). An average market price of $.80 per pound would mean a return of $17.60 per calf. Removing the calves a second time resulted in an additional $8.00 per head return (5 days x 2 lbs./day x $0.80) for a total of $25.60 additional revenue per calf.
In addition to a shorter average calving interval, short term weaning resulted in a substantial increase in the number of cows that conceived during the first 21 days of breeding. Every calf born in the first 21 days of the calving season will be worth an additional $33.60 (21 days * 2.0 lbs. * $.80) over later-born calves.
|No calf removal||1 time removal||2 time removal|
|First 21 days||50.9||60.5||63.8|
|Second 21 days||40.3||34.3||31.9|
|After 42 days||8.8||5.2||4.3|
“In our experience, providing milk replacer was a waste of money,” says Mr. Zumbrunnen. “Really all you need is some good quality grass hay and water and the calves did fine.”
There were no health problems reported as a result of the short-term removal of the calves from the cows. Weaning weights were collected from all the calves and there was no statistical difference in weights between the calves whether they were removed from their dams or not according to Mr. Zumbrunnen.
“Whether we didn’t remove the calves or in the groups removed once or twice, it didn’t change anything. They were all within two or three pounds of each other.”