Good quality colostrum helps protect calves against disease in the first 4–6 weeks of life by the provision of antibodies. Research has shown that the provision of an adequate volume of clean, good quality colostrum as soon as possible after birth has long-term benefits. These include reduced veterinary costs and increased milk production in the first and second lactations. However, colostrum can become heavily contaminated during the collection, handling and storage processes.
Contaminated colostrum can not only be the source of some major infectious diseases, such as Salmonella, Bovine Johne’s Disease and Mycoplasma, but the presence of these pathogens in colostrum can also inhibit the absorption of antibodies by the small intestine of the calf. Therefore, calves fed contaminated colostrum are at a higher risk of disease and failure of passive transfer of immunity.
Possible sources of contamination include the teat skin, milking cup liners, hoses or the bucket itself. Sub-optimal cleaning of collection buckets and feeding equipment such as teat or tube feeders will exacerbate this problem. If allowed to accumulate, colostrum residues can be difficult to remove allowing bacterial overgrowth in hard-to-reach areas. It is ideal to thoroughly wash all feeding equipment after each use, including the sanitisation of tube feeders between calves. A simple protocol for the cleaning of feeding equipment is outlined below.
For ALL feeding pails and tube feeders at the end of every feeding
Rinse all equipment with lukewarm water, to remove milk residue, manure and dirt. Do not use hot water at this stage as it causes the milk proteins to coagulate and stick to the surfaces.
Use water as hot as you can stand with gloves on. To a 20 litre bucket (~19 litres of water), add a squirt of liquid soap and 50mls of household bleach (150ppm)*. Scrub all surfaces to loosen and remove remaining milk residue. Dump teats in solution. Water should remain >50oC.
3. OPTIONAL RINSE
For large milk carts and tanks, rinse with dairy acid wash.
Allow feeders to drain and dry (upside down on top of a pallet) before hanging on racks. Do not stack inside each other. For the sanitisation of ALL tubes of tube feeders in between calves
1. The tubes of tube feeders should submerged in a sanitising solution of 160mls bleach in 19 litres of water (500ppm)* in between calves.
2. Several tubes should be used at once and rotated between calves, to allow sufficient contact time of disinfectant.
*Source: S. Leadley, Attica Veterinary Associates
As bacteria are microscopic organisms it is difficult to crudely assess the cleanliness of colostrum on-farm. However a simple and inexpensive test (called a Total Plate Count or MUC-Test) allows an objective and comparable assessment to be made. Samples of colostrum should be collected at all stages of the colostrum handling process. These include immediately after collection from the cow, colostrum from the test bucket and tube feeder and after colostrum has been stored in the fridge or thawed after freezing. The samples are processed in a lab and the bacteria from colostrum are grown over a 24 hour period in an incubator. This test will not differentiate the various species of bacteria but will give an overall objective assessment of how clean the colostrum is. The test is repeatable and comparable and allows monitoring of colostrum handling and storage during the calf rearing period.
These are MUC-Test plates of dirty colostrum on blood and MacConkey agar. The blood agar shows the total plate count and the MacConkey shows the coliform count. Both plates show a high level of contamination in this colostrum sample. Dirty colostrum can be the source of infection in your calves.
Warrnambool Veterinary is pleased to launch the Colostrum First program that provides ongoing advice and monitoring of your colostrum handline practices, including hygiene. Please speak to your vet for further information.