Feeding large amounts of milk benefits calf growth and health, but only if that milk is safe for consumption. Contaminated liquid represents a major risk to calves. Although milk replacer has a relatively low risk of contamination under ideal conditions, the automatic feeding system adds several new potential sources of bacteria. These include the mixing tank and tube, where liquid milk is frequently present, but also the milk powder storage area and the nipple from which the calves drink.
The recommended bacterial contamination of milk fed to calves must be below 100,000 cfu/mL for SPC (standard plate count) and 10,000 cfu/mL for coliform bacteria (McGuirk and Collins, 2004). Research shows significant differences in the bacterial count of the feeder tube (anterior to the nipple from which the calf drinks) and mixing jar of automated calf feeders on different farms (Jorgensen et al, 2017). The range for SPC varied between 6,668 to 82,825,000 cfu/mL and for coliform bacteria between 45 to 28,517,000 cfu/mL.
Environmental temperature is an important factor influencing the rate of proliferation of bacterial cells. Automatic feeders are often installed in a heated room to avoid freezing. However, a combination of this heat, a lack of ventilation in the feeder housing and any errors in machine installation or maintenance that allow milk to pool in the feeder mixing tank or tubing could contribute to bacterial growth.
Therefore, it is important to explain to farmers why, when and how to clean the feeder. The Lely Calm HygieneBox enhances the system by including a fully automated hose-cleaning circuit. The complete pump-hose system can be automatically flushed up to four times per day, optionally. One or two detergents can be used: Lely Calm Cid, an acidic product, and Lely Calm Lin, a non-chlorinated alkaline product. Due to the external flushing, the teat is also cleaned automatically with clear water after each calf visit. In addition to this, the HygieneBox enables the calves to engage in their natural drinking behaviour. Calves can push the box forward and move the teat vertically while drinking.
Cow health, Milking
Solving mastitis [2/5] healthy teats vitally important
The previous article was about the management strategy concerning mastitis. This article gives an insight into the natural defence mechanisms at udder level and how to support these.