Three Golden Rules of Colostrum Feeding
Two trends that significantly reduce passive transfer start at calving, one in the dam and one in the newborn calf. Firstly, colostrum formation ceases at calving and any delay in the time of milking results in a drop in Ig concentration in the available colostrum (Chelack, et al., 1993, Davis, 1998, Kruse, 1970, Porter, 1972). Secondly, the process of gut closure in calves starts at birth and progresses rapidly with time (Stott, et al., 1979a) and is complete by 24 hours of age. Therefore colostrum should be milked from the dam and fed to calves as soon as possible after birth in order to:
- optimize Ig absorption,
- decrease migration of pathogenic organisms across the intestinal epithelium,
- provide nutrients essential for heat production, vigour, and initiation of important metabolic pathways, and
- supply growth factors and hormones that stimulate intestinal and immune system development.
- Calves should receive their first feeding of colostrum as soon as possible after birth, and not later than 6 hours of age. An attempt should be made as soon as possible after birth to determine if calves are too weak, unable, or unwilling to suckle. If so, they should be fed colostrum immediately by oesophageal feeder.
- Calves that are not seen until older than 6 hours of age should be fed immediately, and if they will not suckle on an initial attempt, should be fed with an oesophageal feeder without delay.
- Calves that are born unattended or are left with their dam should also be hand fed as soon as possible after birth. This is because studies in dairy cattle have shown that there is a significantly higher rate of FPT in calves left to suckle their dams than in calves that are hand fed (Besser, et al., 1991, McCoy, 1970), and it should not be assumed that calves born unattended have consumed an adequate amount of colostrum.
- Feed calves at higher risk of FPT extra colostrum as soon as they are identified .
Ideally, colostrum should be milked from the dam within 30 minutes after birth and fed to the calf immediately. The preferred feeding methods are for the calf to suckle from a nipple bottle or pail, however, calves that are unwilling or unable to suckle should be fed by oesophageal feeder or stomach tube. When calves suckle or drink from a pail the colostrum passes through the oesophageal groove directly into the abomasum where clotting and subsequent rapid passage of the Igs into the intestine occurs. When colostrum is administered by oesophageal feeder, it is deposited into the rumen and there is a delay of 3 to 4 hours before all of it is passed into the abomasum (Lateur-Rowet and Breukink, 1983). This can lead to a reduction in Ig absorption. Studies have shown that stimulation of calves to breathe and placing them on their chest and/or encouraging them to stand increases Ig absorption.
Good quality colostrum is defined as having the following characteristics.
- Safe – A variety of pathogenic organisms can be present in the udder, either by transmission from the dam’s blood or by direct infection, and can be passed to the calf through the colostrum. Since these can all have a major economic impact on the herd, diagnostic screening of cows should be done before parturition whenever clinically sick animals have been observed or when these diseases are suspected the herd. Colostrum and milk from dams infected with any of these diseases should not be fed to newborn calves if any attempt is being made to control or eradicate the diseases from the herd. These diseases are listed in the table to the right.
- Potent – Colostrum fed on Day 1 should have an IgG concentration >50g/L. The IgG concentration in the first milking from Holstein cows ranges from <16 to >100 g/L, but averages about 50g/L (Besser, et al., 1991, Pritchett, et al., 1991), and slightly higher in Jersey cows and beef cows (Besser and Gay, 1994). The IgG concentration cannot accurately be judged visually, and the chances of selecting the best quality colostrum can be improved by using a colostrometer. It is recommended that only first milking colostrum be fed before gut closure (i.e. on day 1), and later milkings should be fed after day 1.
Most farms do not have a continuous supply of fresh high quality colostrum available at all times and producers who want to feed only high-quality colostrum need to maintain a reserve supply for calves born to dams that produce colostrum of low quality or insufficient volume. To meet this need, frozen storage of maternal colostrum and the use of colostrum substitutes have become common. The following are guidelines for collecting and storing excess colostrum.
Collection and Storage of Colostrum
Provided it is relatively uncontaminated, colostrum can be stored refrigerated for short periods of time. One report using human colostrum suggested it could be stored in plastic containers for 7 days without loss of activity if kept at 4º C (Manohar, et al., 1997). However, other authors working with bovine colostrum reported a significant loss in Ig concentration in samples stored in a refrigerator for 7 days, or at 30º C for 1 day (White, 1993). Therefore, it is likely best to not feed colostrum that has been refrigerated for more than 48 hours. Colostrum can be stored frozen for longer periods, exceeding a year, without Ig deterioration (White, 1993). For storage, colostrum should be divided into 1 to 3 L amounts so that it cools quickly, and to provide volumes convenient for feeding later on. Each aliquot should be labelled with the cow or pool identification, date and quality information. Storing colostrum in frost-free freezers should be avoided because repeated thawing and freezing cycles will lead to deterioration. For feeding, frozen colostrum should be thawed by immersing the container in hot water (45º to 55º C) with care being taken to avoid temperatures in excess of 60º C. Using a microwave oven to thaw colostrum, even on a low setting, may lead to variable results and Ig damage (White, 1993). Colostrum should be fed at or slightly above body temperature.
As a safe and convenient alternative to freezing colostrum, good quality commercial sources of colostrum substitutes are now available.
Selection of Colostrum Donors
Good quality colostrum is usually defined as having > 50g/L of IgG. The volume of colostrum produced at the first milking has a significant affect on IgG concentration, so that larger volumes are associated with lower IgG concentrations (Pritchett, et al., 1991, Pritchett, et al., 1994). In North America a first-milking volume of less than or 8.5 Kg is one of the recommended selection criteria when identifying cows to be used as colostrum donors. Studies have also shown that delaying the time of first milking results in lower colostral IgG levels, so that colostrum collected at 6 hours post-calving has IgG levels up to 40% lower than colostrum collected within 2 hours of calving (Davis, 1998). Cows that have aborted have been reported to produce colostrum of poor quality (White, 1993) and should not be used as donors. Key selection criteria for colostrum donors are summarized in the following table.
Selection Criteria For Colostrum Donors
|1. Health status||Avoid using cows with clinical disease or an unhealthy udder|
|2. Disease carrier status||Avoid using cows that have tested positive for any of the diseases that can be transmitted through colostrum (see list above).|
|3. Volume of first milking||Select cows that give a first milking volume less than 8.5 Kgs|
|4. Vaccination status||Use donors that have been vaccinated during the dry period for diseases found in the herd|
|5. Premilking or leakage from the udder||Avoid cows that have been premilked or that have leaked significant volumes from the udder before calving|
|6. Length of dry period||Although there has not been much research on this topic, general recommendations are to avoid using cows with excessively long (>70 days) or short (<30 day) dry periods.|
It is strongly recommended that colostrum from other herds or premises not be used because of the disease transmission potential mentioned previously. While the volume and IgG concentration is on average a bit lower than in older cows, first calf heifers can produce an adequate Ig mass (Pritchett, et al., 1991) and should be used when they meet the criteria listed in the above table.
Some researchers have recommended against the pooling of colostrum from multiple freshening cows because there is a tendency for pools to contain larger volumes from cows with lower IgG concentrations, and this reduces the IgG level in the entire pool (McGuirk and Collins, 2004). However, this can be overcome by limiting the volume used from any individual donor cow to not more than 8.5Kg. Under this practice the average IgG concentration in pools should tend towards >50g/L.
The critical factor is the amount or mass of IgG that must be fed to achieve successful passive transfer and this varies depending on the time of feeding, the IgG concentration, and other factors such a stress. Because the efficiency of colostral absorption is highest immediately after birth and decreases with time, to achieve successful passive transfer more IgG must be fed as time passes. There are many management practices that can affect the calves' passive transfer, and the following three are common under modern North American management systems.
- Calved cows are not milked until the next scheduled herd milking time. This results in more volume entering the udder, and a reduction in colostral IgG concentrations.
- Newborn calves are not fed until the next scheduled feeding time, so that some may be as old as 12 hours or even older before receiving their first meal. By this time gut closure is well advanced.
- Colostrum may be collected and pooled from many cows without measuring the quality or controlling the volume used each cow. This can result in average colostral IgG levels dropping below 50g/L.
To overcome the variation in passive transfer that results from these and other variables, common feeding recommendations are that calves should receive a minimum of 100 – 150g of IgG by 6 hours of age. Where the colostral IgG concentration is unknown it is often recommended that calves be fed 3-4 quarts of colostrum at the first feeding. However, even feeding this volume of colostrum may not provide enoughimminity if the concentration of colostral IgG is low.
Provided by The Saskatoon Colostrum Co. LTD.