Headstart for Calves

When they get enough feed they're healthier and need fewer drugs.

"They drink real good for two or three weeks, Doc, and then they scour out and die. I can't find a drug to cure them."

"Too much milk will scour a calf. So I only give them a bottle twice a day".

"Mixing that milk powder too strong makes them scour, so we use less than the label directions."

I often hear comments like these when examining young calves with arched backs, shivers and scours. The essential step in treating these calves is determining feed intake. This is especially true during cold weather when they need more milk.

Many Ontario producers have already found that too little -not too much- milk harms calves. By feeding adequate amounts, they now use fewer drugs to chase bugs.

Recently, two U.S. teachers and researchers, Carl Davis and James Drackley, reviewed the calf feeding literature.

They put their findings on modern calf feeding and management into a very practical and useful book. Everyone who feeds calves or gives advice on calf rearing should buy it and read it, and refer to it often.

You will boost the survival, health and thriftiness of your calves by following their recommendations. Here's some of what you'll find in their book:

Nipple Bottle Size

The widespread availability of the two-quart (1.89 Litre) nipple bottle has been a great disservice to the dairy calf, say the authors. These bottles lock producers into thinking that 1.89 L is a suitable volume to feed, when in fact it's often inadequate. This is particularly true for colostrum. The initial feeding should be at least 2.84 L (3 quarts). Some experts recommend as many as 4 L for initial colostrum intake.

Temperature of Milk or Milk Replacer

Calves housed under cold conditions should be fed liquids at or near body temperature. Feeding cold milk adds a cold load that could further decrease the calf's temperature.

Feeding Amounts

Feeding whole milk at 10 per cent of body weight- 4.5 L for a 45 kilogram calf-with calf starter and water available at all times, is sufficient to produce healthy calves with good appetites for solid feed.

Similarly, feeding milk replacer (reconstituted at 12.5 per cent solids, about 130 g per L) at 10 per cent of body weight (BW) will produce good results. This mixing (130 g per L) and feeding rate (10 per cent of 45 kg BW = 4.5 L = 585 g powder) is far superior to the common recommendation of 454 g of powder per calf per day.

Feed Efficiencies

Growth rates approach 1,000 g per day for young calves consuming free choice whole milk up to 26 per cent of their body weight.

For comparison, calves fed milk or milk replacer at a rate of 10 per cent of body weight gain from 200 to 400 grams per day.

Feed efficiencies improve as rates of gain increase in young calves. Greater growth rates allowed by greater intake dilute overhead maintenance costs.

Length of Feeding Period and Amount of Feed

A longer liquid-feeding period, at higher intakes than typically recommended, results in calves that are better grown, more vigorous, healthier and suffer less slump in growth at weaning.

Feeding Rate and Diarrhea

Feeding milk free choice does not lead to diarrhea. The general level of microbial contamination in a calf- raising environment appears to be more important than the amounts of feed consumed.

Solids or Dry Matter Concentration of Milk Replacer

Milk replacers should be mixed and fed at a dry matter (DM) concentration of between 10 per cent and 15 per cent (about 105 to 160 g per L). For cold-weather feeding, the total amount of powder by weight fed per day could be increased by 25 per cent. This would increase nutrient intake without greatly increasing the likelihood of scouring. However, don't exceed 20 per cent DM concentration (about 205 g per L). Calves fed milk replacer reconstituted to 20 per cent DM are more prone to developing diarrhea.

Alternatively, mix the powder at the same DM concentration and feed 25 per cent more volume. For example, for a 45-kg calf, you would increase the volume of a 12.5 per cent DM concentration milk replacer (130g per L) from 4.5 to 5.6 L a day. This would increase the total milk replacer powder fed from 585 g to 728 g, or about 25 per cent.

Mixing Temperatures for Milk Replacer

The specified temperature of water to use for reconstitution affects dispersion of the emulsified fat in the milk replacer. Some milk replacers require mixing with hot water (water at 60 degrees Celsius or 140 degrees Fahrenheit). However, some milk replacers are agglomerated during manufacturing. This process coats fat droplets with protein and lactose. Agglomerated milk replacers have a larger particle size and different mixing qualities than dry-blended formulations. If the label says the product is agglomerated, then water temperature should be warm (38 to 43 degrees C or 100 to 109 degrees F) rather than hot. Incorrect mixing decreases digestibility.

Evaluating the Quality of Your Milk Replacer

The only truly reliable measure for evaluating milk replacer quality is calf performance. Lack of clot formation with whey-based milk replacers has been incorrectly interpreted as an indication of inferior quality. With today's whey-based milk replacers, the inability to clot with rennet is useless as a quality indicator or as a predictor of calf performance.

Whey-Based Milk Replacers

All-milk-protein replacers based on whey protein products are highly digestible and well utilized for growth by calves. They do not form a clot in the abomasum-only casein forms a clot. The fact that they don't clot in the abomasum is irrelevant for their digestion because whey proteins are naturally digested in the small intestine without action of abomasal proteases.

Milk or Milk Replacer for Cold-Housed Calves

To minimize the effects of cold environmental temperatures, provide extra energy to the young calf. The amount of milk or milk replacer should be increased by about 25 to 30 per cent. If a milk replacer is being fed that has less than 15 per cent fat, switch to one with 18 to 22 per cent fat. Increase the DM content of the liquid milk replacer to 15 per cent (i.e. about 160 g per L).

You can increase the amount of powder fed per day by increasing the total volume of liquid milk replacer (from 10 per cent to 12.5 per cent BW) and using the same DM concentration (130 g per L) used during warmer weather. Alternatively, you can increase the amount of powder fed per day by increasing the DM concentration of powder (from 130 g per L to 160 9 per L) and feeding the same volume (10 per cent BW).

Breed or Age of Calf and Lower Critical Temperature

The thermoneutral zone is a range in environmental temperature of 10 to 15 degrees C within which heat production or metabolism of the calf is relatively constant. The lower critical temperature is the point in environmental temperature at the lower end of the thermoneutral zone that elicits an increase in heat production. The lower critical temperature is 8 degrees C for Ayrshire calves, 10 degrees C for Jerseys and 12.5 to 14.5 degrees C for Holsteins.

In calves one week old or younger, the lower critical temperature is in the range of 13 to 20 degrees C and it declines with age to about 7 degrees C by 25 days. Greater energy intakes decrease the lower critical temperature. Increasing age and greater energy intakes provide the calf with greater heat-producing capabilities and insulating properties in the form of thicker skin and larger stores of subcutaneous fat.

Weaning From Liquid Diets

Weaning at four to five weeks of age requires more individual animal attention than weaning at six to eight weeks when dry feed consumption is greater. As the DM from the liquid decreases, DM for solid feed will increase. A gradual weaning approach allows a smoother transition, especially for younger calves. Decrease milk or milk replacer by one-half for three to seven days.

These examples are only a few from a very easy to read book. Readers will find many additional tips for successful calf raising. It's no fun to work with sick calves. Follow the practical advice in this book and you will put more fun into your calf husbandry.

This article first appeared in the July 2001 Ruminations column of the Ontario Milk Producer.

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