The 4 essential aspects of proper calf management
Calf management always needs to be a top priority on farms. We cannot afford to make mistakes in this period as deficiencies can be difficult to correct. Calves, and especially replacement stock, are the future milking herd, and issues early in life can have adverse effects further down the line regarding delayed calving age and milk yield.
Regardless of your production system, getting the basics right is crucial. We need to focus on four key areas:
- Rumen development
The three words that are critical when it comes to colostrum are ‘get in early.’ The quality of the colostrum or the ability of the new-born calf to absorb its benefits reduce quickly with time. Colostrum is the first nutrient source a calf will receive, and supports the calf’s immune defence. The first hour is when the calf can absorb these antibodies most readily, so we need to get colostrum into the calf as soon as possible. The capability to absorb these antibodies declines rapidly after the first hour and completely stops at 24 hours.
A good way to remember is to use the well-publicised rule of ‘3-2-1,’ which is at least three litres of colostrum within two hours of birth for the first feed. The only exception to this is Holstein calves, which will require four litres. A second feed should then be given within eight hours before transitioning on to milk/milk replacer. Quality of colostrum also needs to be taken into account, and it can be measured with several devices that are freely available and quite inexpensive.
A calf is best able to convert feed into weight gain in the first few months. Beyond this point that ability will decline, so we need to make sure we get the most out of this short period. A calf should, at least, double its birth weight before weaning at 10 weeks, meaning a 40 kilograms calf needs to gain 0.6 kilograms per day. This can be a difficult target to reach.
A calf should be fed for 15% of its body weight, so for a 40-kilogram calf that is six litres per day. It should be noted that the abomasum is not large enough to deal with six litres of milk at once, so the feed should be split. Milk replacer should be aligned with weight targets and, as it has a lower fat and energy content than whole milk, it will need to be fed at a higher rate. It is also worth paying attention to temperature, as a lot of milk/milk replacer volumes and target weight gains are based at 15oC when a lot of calf houses at this time of year are not even close to this. In this, even more milk/milk replacer is required to achieve the target weight gain. Temperature should also not be confused with airflow.
Calves require 325 grams of milk solids for maintenance. Milk is 12.5% dry matter, which equates to 2.6 litres. So, a calf of 40 kilograms being fed four litres can only gain 200 grams per day, meaning it would take a long time to achieve the weaning weight or being weaned at a low weight.
Water is a vital part of calf nutrition and one that is often overlooked if they are on milk. Ideally, water drinkers should be checked every day to make sure that there is always fresh, clean water available. It is important to remember that milk goes into the abomasum, bypassing the rumen, hence there is no water/moisture to aid the digestion of the calf concentrate in the rumen.
At InTouch, we do not advise feeding hay or silages to pre-weaned calves, as this can negatively affect starter intakes. It is reasonably palatable, so a large consumption of this material can lead to ‘pot belly’ calves when the rumen is not developed enough to digest it. The use of 8%–10% of chopped straw as part of the calf concentrate can encourage rumen strength, as well as allowing the concentrate to be fed safely between weaning and grass, or any other changes in diet. The starch in the concentrate will help to drive papillae development. It is also important to make sure any concentrate is highly palatable and dust-free to avoid respiratory issues.
Immunity is another vital element in heifer rearing. Good quality minerals in both the dry cow and calf diets are essential in helping aid the calf immunity as they develop.
The inclusion of products such as Actigen® and BioMos® as part of your calf concentrate can support immune function and help in the development of a healthy gut and rumen. It is important to ask your feed supplier if these products are included in your calf starter.
Environment is also a crucial parameter when it comes to calf rearing, as it is here that the calf will meet the most challenges in life. As calves spend 80% of their time lying down, it is essential to have a clean and comfortable bed. The fall on the floor of calf lying areas is sometimes not enough to remove moisture or the depth of straw, which should come up around the calf, is often not enough to provide warmth and comfort. By lying on a cold, wet bed, energy will be used for warmth rather than growth, outside of the threats caused by sickness, etc. Calves will need at least 1.1 square metres of lying space up to eight-weeks old, and 1.5 square metres thereafter.
Hygiene is also an important factor, and it does not matter whether you are using a bucket, nipple bar or automatic feeder. Often, the volume of milk is blamed for calf scours when it is, in fact, the hygiene around milk feeding. Washing our implements properly and allowing them to dry can go a long way in the solution.