Getting the Cows Ready to Calve and Re-breed

It's the most wonderful time of the year. No, I am not talking about Christmas, but that magical time when the cows begin to drop their calves. And like any Christmas, preparation before the day comes helps make it a truly special time.

Picture of cow with calf

Figure 1: Successful cow management produces healthy cows with vigorous calves

The dairy industry talks a lot about transition cow management, the three weeks prior to calving to the three weeks post calving. This is a very critical period in the cow's life. For the beef industry, if we extend the transition period, from two months prior to two months post calving, we can manage the most critical period of a cow's life smoothly.

There are three things to consider in transition beef cow management: sorting, nutrition, and health. The sorting should occur about 60 days prior to calving. Evaluate your cows for body condition score.

Cows in this period should be in the 3 to 3 ½ score on a scale of 1-5, with 1 being thin and 5 being obese. This puts the cow in a position to gain weight as the fetus grows prior to calving, and then gradually lose condition as she milks the fat off her back. As you look over your cows you may discover some which are under conditioned, in other words, in a 2 to 2 ½ condition score. If possible, these cows should be sorted to provide a higher plane of nutrition with more energy.

Why should you worry about body condition scores on your cows? Cows in better condition have healthier, more vigourous calves. As well, cows in better body condition tend to start cycling earlier after calving. This allows cows to be re-bred more uniformly, providing a more consistent calf crop the following year. The calves from this calf crop will calve earlier, providing heavier calves at weaning.

Table 1 demonstrates the result of higher energy fed to heifers in various body condition scores, and the impact on birth weight and body heat of the calves born. Calves from heifers in body condition scores of 2 ½ or higher in the last 45 days before calving were heavier at birth, and produced more body heat (a sign of a more vigourous calf).

Table 1. Effect of nutrition during the last 45 days before calving on heifer weight gain and calf health
Trait
Condition Score
2
2.5
3
Weight Gain by Heifer (lbs)
48.4
90
136
ADG of Heifer (lbs/day)
1.1
2.0
3.0
BW of Calf (lbs)
80.1
90
85
Calving Ease Score
2.3
2.8
2.2
Heat Production of Calf
Medium
High
High

Heifers that calve in good body condition have less dystocia (problems calving). Studies show that the calves will be bigger (5-8 lbs.) but the heifers have more energy to push those calves out. As well, anecdotal evidence has shown that cows which are exercising more prior to calving have less dystocia than cows which are kept in pens. Having cows walk to water or feed provides muscle tone for the entire body, and may help them deal better with the physical stress of calving.

Once cows have been body condition scored, decisions can be made on feeding the 'mommas to be'. Research shows that cows in good body condition which are fed a lower plane of nutrition during the last 60 days prior to calving have more trouble calving than cows that are thin and are fed more energy for the last two months. Table 2 shows the results from one study on the effect of energy intake pre and post partum on the percent of cows in estrus by 60 days post calving, and on weaning weight of the calves. Keeping your better forage for the transition period is definitely a good management decision. Cows in late pregnancy cannot eat as much because of the calf bed pressing into rumen space, so the ration should be more energy dense. As well, making sure that the cows are receiving a well balanced mineral and salt package, with extra Vitamin E and selenium, helps set the cow up to calve and re-breed.

Table 2. Effects of Pre- and Postpartum Energy Intake on Reproductive Performance and Calf Weaning Weight*

Prepartum Nutrition
Postpartum Nutrition
Postpartum Interval, days
Percent in Estrus by 60 d
Calf 205 day Weaning Weight
Low
Low
73
33
409
Low
High
54
56
455
Maintenance
Low
66
53
444
Maintenance
High
68
54
482

*Rick Funston, Montana State University

Another avenue to look at in getting cows ready to calve is health management. Controlling lice prior to calving is recommended. As well, studies show that vaccinating cows for scour prevention can help the calves with stand scours challenge. At this time, you can also vaccinate for respiratory diseases, if your vaccine can be used on pregnant cows (always follow the directions on the label). Clean well-bedded pens, or better yet, clean grass on pasture, reduces the disease challenge for new born calves.

You should review your calving kit to make sure all your tools are ready for the most wonderful time of the year. Proper cow management prior to calving will prevent a lot of headaches during this happiest time of the year on the cow-calf.

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