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What are your calves telling you?

Bob James for Progressive Dairyman Published on 24 November 2017

Observing dairy calf behavior is a critical skill in the early detection of disease. Dr. Sheila McGuirk from the University of Wisconsin published an excellent health scoring publication guide (Calf Health Scoring Guide) used by many calf raisers, veterinarians and researchers to aid in disease detection.

It relies on presence (or absence) of a cough, nasal discharge and scores for eyes, ears, feces and nesting. However, are there additional behavior traits that can make early illness detection even more effective?

Historically, we have housed calves in individual pens and fed them limited quantities of milk or milk replacer twice a day. These management practices have been recommended since they limit calf-to-calf contact for disease prevention and encourage early calf starter consumption and early weaning.

Additionally, calves are commonly fed twice daily at times that conform to labor availability, with intervals of eight to more than 16 hours between feedings on some farms. In these situations, the calf feeder is commonly greeted at feeding times by loud bellowing of calves and extremely agitated behavior. These calves are hungry. We have come to expect this as “normal” behavior, but is it really?

How do group-housed calves fed more frequently differ? Beef calves raised by their dams commonly nurse four or more times daily and consume smaller but more frequent meals of milk. Angus calves commonly consume 5 to 6 quarts of milk daily prior to 7 days old.

Several weeks later, they may consume as much as 10 quarts daily. Dairy calves housed in groups and fed milk via automatic computerized feeders or in acidified free-choice systems have demonstrated their behavior is quite different from limit-fed individually housed calves.

What is different, and can these differences in behavior be used to supplement the scoring system developed by McGuirk?

  • The first thing noticed with calves fed larger volumes of milk, whether through auto-feeders or acidified systems, is calves are quieter. They don’t respond when people enter the calf facility unless the feeder is empty or frozen.

  • Much like the individually housed calves, group-housed calves will commonly lie down and almost seem to go to sleep after a full meal.

  • It is recommended to provide at least 35 square feet per calf in group-housed systems. With this resting space, calves often run around the pen with their tails up in the air several times daily. This frequently happens when pens are re-bedded and at other times of the day.

  • Group-housed calves generally adjust to the weaning process more easily. First, they are already used to being housed with other calves and “competing” for feed. Second, calves seem to “teach” each other where the calf starter grain is located. Third, the milk withdrawal tends to be more gradual, allowing a less stressful transition to dry calf starter grain or forage.

  • These behaviors are observed in systems using acidified free-choice liquid diets or auto-feeders. The advantage of the auto-feeder systems is: There is valuable information collected by the auto-feeders on each individual calf that can be used to monitor feeding behavior and possibly early disease detection. This information is listed below.

o Nearly all auto-feeder systems record how much milk each calf consumes per day and compare it to the previous day or days. It’s not uncommon for calves to vary their milk consumption, particularly when they are offered more than 8 quarts per day.

However, declines in milk exceeding 2 to 4 quarts per day are cause for concern. This is an indication for closer examination of the calf. Figure 1 shows an intake pattern for a calf demonstrating a rapid drop in milk intake.

Record of daily milk intake by single calf on an automatic feeding system

More sophisticated systems compare today’s intake with the average of the previous three days.

o Drinking speed is recorded by some equipment and appears to be one of the more reliable indicators of approaching illness. “Normal” drinking speed may vary between 0.4 to as much as 1 liter per minute.

Calves with diarrhea may start drinking more slowly as much as three days prior to onset of diarrhea serious enough to require treatment. (Most auto-feeders use the metric system.) Unfortunately, onset of respiratory disease tends to be more rapid, and drinking speed doesn’t appear to be as useful an indicator of impending disease.

Unrewarded visits mean the calf is hungry but not allowed to obtain a milk meal either because they have consumed the maximum amount of milk allowed for a visit or per day. More sophisticated feeding systems are programmed to limit the size of a milk meal.

Generally, meal sizes for younger calves are limited to about 1.5 quarts per meal. Maximum meal size increases to as much as 3.5 quarts, as older calves consume larger meals less frequently. If meal size is too small (less than 1 quart), the calf is not satisfied and stays in the feeder or tries to return within a short period of time to get more milk or milk replacer.

Daily meal allocations less than 7 quarts per day will typically result in more unrewarded visits to the feeder. Under these same restrictions, sick calves will reduce unrewarded visits. Acidified free-choice feeding systems or automated calf feeders are not practical for many dairies. However, behaviors of calves housed in individual pens or hutches should be observed. This requires an observant calf feeder.

  • Watch how quickly and vigorously calves consume their meals. Calves with strong appetites are healthy.

  • Sick calves in the early stage of digestive disease may consume their given a.m. or p.m. meal, but they will do it more slowly.

  • Watch for changes in calf behavior, as there’s a great deal of variation between calves in many of these measures, but reductions in drinking speed are the key indicator.

  • Calves consuming two meals a day may have difficulty consuming larger volumes of milk per day (greater than 8 quarts). They will generally have a strong appetite in the morning, especially after a long, cold night, and may not consume their meal in the afternoon feeding, particularly if the interval is less than 10 hours from the morning feeding.

I frequently hear the comment dairy calves won’t or can’t consume more than 8 quarts of milk per day. However, if one walks through the barn within a few hours of their last milk meal and calves come out to greet the person, it’s a good indicator they are still hungry and will welcome more milk or milk replacer.

There is a way to capture some of the advantages of group feeding with calves housed in individual pens or hutches. Research conducted in Canada and experiences of dairies in North America have shown removal of a pen divider between two calves or housing two calves in one hutch (with a larger outside pen) around 4 weeks old enables one to capture many of the positive behavioral advantages of group-housing systems.

They consume starter more readily and seem to adapt to group housing more easily once weaned from milk. Becoming a better student of calf-feeding behavior can be a valuable adjunct to the calf health scoring system developed by McGuirk and colleagues at Wisconsin. It’s another tool toward preventive health management of dairy calves.  end mark

Bob James is with Down Home Heifer Solutions Inc. Email Bob James.

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