Welcome to The Dairy Mail

by Liza Burger

Excellent calf-rearing is one of the cornerstones of profitable dairying. Without a steady source of healthy calves, no dairy farm can sustainably continue to exist. Replacement heifers ready to enter the milking herd will only be as good as the months they spent preparing for their lives as dairy cows.

Developing the rumen of the young calf, keeping the calf healthy, feeding it the right food at the right time and taking care to introduce the calf to the group dynamics, are but some of the main aspects of efficient calf-rearing.

No farms are the same and what works on one might not succeed on another. No farmer raises his calves exactly like the next, and while some tried and tested methods cannot and should not be ignored, others are open for interpretation.

Happy birthday
Cows should preferably calve in a clean calving paddock or calving pen, separate from the rest of the herd. Maternity boxes should be disinfected after each calving. Remember, calves only receive their first shot of antibodies when taking in colostrum and need to be protected from any form of disease and infection, especially at birth.

Immediately after birth, check if the calf is breathing. Especially after a long and difficult calving it might be necessary to massage the calf’s chest to stimulate breathing. You can also tickle the inside of the nostril with a piece of clean straw to induce a sneeze, forcing the calf to take a breath.

If the calf is allowed to stay with the cow directly after birth, she will lick the calf clean and dry. This is necessary to stimulate circulation and to allow the calf’s coat to dry and insulate the young animal against cold conditions.

By removing the calf prior to the cow’s licking, the stockman must fill this role by rubbing down the newborn calf. A dry and fed calf will be able to resist cold surprisingly well. Also, take care to clean the nose and mouth of any remaining foetal membrane.

Clean the calf’s navel cord with an iodine solution prepared for this function. Cover the cord and the hair on the belly.

Record the calf’s identity, birth date, dam and sire’s identification. Make notes of relevant details such as a difficult calving, any diseases (both calf and cow) or problems with the calf.

First meal
Some farmers believe in leaving the newborn calf with the cow for three to five days. Others prefer to remove the calf immediately after birth and to bottle feed the calf its colostrum.

Whichever way you choose to rear your calves, one factor must not be compromised: feeding as much colostrum as possible within the first day after calving.

The colostrum intake of bottle-fed calves are easier to monitor. The huge udders and teat placement of the modern-day dairy cow are said to be less natural and suitable for a suckling calf and studies show that some calves cannot feed as well from their super-bred mothers.

However, some believe that the cow can see to the needs of her calf better than any human and that she can provide that very first day’s meal ad lib instead of the set times and quantities of hand reared calves. However, not all cows are successful mothers, making this method less effective in some cases. More than 40% of calves left with the cow after birth have been found to show insufficient antibody protection owing to the poor intake of colostrum.

Some facts you should know about colostrum and the way the calf absorbs this antibody kick-start in life, include:
• Colostrum is the calf’s only source of protection against bacterial diseases in early life.
• The rate of absorption of the protein anti­bodies, is greatest within six hours after birth.
• If bottle fed, the stockman should focus on feeding the calf as much colostrum as possible within the first eight hours after birth.
• For the best results in transferring maternal immunity to the calf through the colostrum, bottle feed an amount of about 5% of calf’s bodyweight, 15 minutes after birth.
• Colostrum is high in energy and has a high oil content. Only later in life will high-protein feed become more important.
• To help the lymphatic system develop and encourage disease resistance, colostrum is rich in vitamins such as vitamin A.
• Colostrum is a natural laxative, clearing the digestive tract in the first few days after birth.
• Older cows have better quality colostrum than cows that calve for the first time. They also produce colostrum with a more diverse antibody population. Colostrum from these cows can be frozen and stored for later use.
• About 24 hours after birth the calf loses the ability to absorb antibodies from the colostrum. You can, however, continue to feed colostrum for another day or two, as it is nutritious and still has disease-controlling effects by neutralising pathogens in the stomach lining.

Bottle-feeding – and force-feeding with a stomach tube, when necessary – means greater control over colostrum intake. You have to take the weight and size of the calf into account, but a general rule of thumb is to feed calves weighing less than 30 kg, 1 to 1,5 l of colostrum. Ayrshire, Guernsey and dual-purpose breeds with calves weighing 30 to 40 kg can be fed 1,5 to 2 l. Larger calves of 40 kg and more can be fed 2,25 to 2,5 l of colostrum for their first meal. Feed the calf again within eight hours. Colostrum is best served at body temperature (37°C) and should be given three or four times in the first 18 to 24 hours of life.

After this first day, the general amount of milk typically fed to a calf is 8 to 10% of its birth mass, three times a day for the first three days.

Overfeeding can cause the milk to overflow into the undeveloped rumen which may lead to scours. However, some farmers successfully feed their calves up to 8 l of colostrum in the first day. The problem is more often that calves are not fed enough colostrum as opposed to being overfed.

Remember to remove other feed and water at least half an hour before and after feeding milk or milk replacer. Always feed milk at the same temperature. Body temperature is preferred by many farmers, but the most important factor is a stable temperature serving of milk throughout the time that the calf is fed.

Teats or buckets are both used successfully in calf-rearing. Remember to teach your calves how to drink from buckets or suckle from group feeders, especially if the equipment is different to the method used for feeding colostrum.

All equipment used in feeding calves should be disinfected after every use. Use effective cleaning chemicals and reliable staff to oversee this process. Keep each calf’s bucket and feeding equipment numbered and serve its food from the same clean buckets daily.

Consult a professional ruminant specialist to improve rumen development in your calves.

Housing for calves
There are many shapes, forms and methods of effective calf-housing and more than enough information to fill a whole book. Some basics are not negotiable; therefore, you might want to see how many ‘yes’ boxes you can tick off the following list:

• Calf-housing should be easily accessible.
• Removed from older cows.
• Face away from too much direct sunlight to avoid excessive heat.
• Have an ambient temperature of 15°C.
• In warmer climates, have effective ventilation to help cool down the housing.
• In cooler climates, have ways to insulate housing from freezing temperatures and wind.
• Humidity should be above 50% and optimally at 70%.
• Fit a thermometer to monitor temperature and a hydrometer to measure the level of humidity.
• Ventilation must provide fresh air, but not a draft. This will provide the build-up of ammonia, carbon dioxide and humidity. Poor ventilation can lead to calf pneumonia.
• Calves must have a clean, dry pen.
• Achieve good drainage with a slightly sloped floor or with raised calf pens with grid flooring.
• Provide enough space for some movement. Individual pens are typically 1,8 x 1 m.

Avoiding the S word
Scours is a common disease among calves. It is typically the result of metabolic upsets of an imbalance in the digestive tract, causing
diarrhoea.

This leads to dehydration and a loss of electrolytes and can cause the calf to die. Scours can be caused by toxins from infectious organisms, poor-quality protein, fat or carbohydrates in milk replacers. A change in the diet and irregular feeding can also cause scours.

Other factors that may lead to scours, include milk fed at different temperatures, unhygienic feeding methods and utensils, poor-quality feed and mouldy hay, calves suckling each other and spreading the disease.

Opsomming
Om gesonde kalwers groot te maak is nie altyd ’n maklike taak nie. Daar is egter ’n paar basiese riglyne wat ’n mens moet volg om nie net die kalf veilig en gesond te hou nie, maar ook om ’n goeie groeikoers te handhaaf en rumenontwikkeling te bevorder.