Udder health is of major importance to milk production, cow welfare and farmer working happiness. Basically, every case of mastitis occurs due to bacteria that have managed to enter the udder via the teat sphincter and teat canal. The teat skin, the teat canal and the teat sphincter form the first – and most important – line of defence (Neijenhuis, 2004).
The teat skin is the first line of defence against invading pathogens and, when intact, provides a hostile environment for bacteria, thus preventing their growth. Changes in the teat skin can enhance bacterial colonisation on the teat (Neijenhuis et al., 2001). The normally intact surface of the skin may become compromised by cuts, cracks, chaps, bruising or lesions, etc. Poor teat skin can be caused by environmental factors such as the cold, wet or muddy conditions or dry bedding material that draws moisture from the skin.
The canal is located at the bottom of the teat. As the bacteria causing clinical mastitis need to enter the udder through the teat, the teat canal is an important defence mechanism in intramammary infection. The teat canal is usually closed off by the teat sphincter (a circular muscle) and lined with keratin, which has an inhibitory effect on bacterial growth and forms a barrier against potential bacterial invasion. During milking, the teat sphincter opens and the keratin layer is removed, resulting in a risk for a bacterial invasion (Lacy-Hulbert & Woolford, 2000). As a result, it is important to maintain excellent hygiene standards at the milking robot and, for instance, always replace liners on time. Whether you are milking with silicone or rubber liners, Lely advises replacing them regularly: silicone after 10,000 milkings and rubber after 2,500 milkings.
After milking (before the teat sphincter has had the opportunity to close up and the keratin layer has been restored), bacteria can still enter through the teat canal. It takes at least 20 minutes to 30 minutes for the teat to become fully closed after a milking. Udder health products provide disinfection to bridge this vulnerable period when the teat is still open after milking. Hence, to protect the teat from bacterial contamination, it is also recommended that animals should not lie down for at least 30 minutes after milking. Cows prefer to drink after milking and during feeding, so it is really important to provide an adequate and clean water supply for them.
Poor teat-end condition (teat-end hyperkeratosis) (link naar art 2 - melkproces) can be caused by poor milking performance, such as the wrong milking settings, overmilking (Hillerton et al., 2002) or poor teat liner fit (Zucali et al., 2008). Teats with a bad skin condition have a higher risk of developing teat-end hyperkeratosis. Teat-end hyperkeratosis increases the risk of infection of the mammary gland (Cerqueira et al., 2018). The condition of the teat end plays a very important role in the defence against invading pathogens.
Udder health is of major importance to milk production, cow welfare and farmer working happiness. Basically, every case of mastitis occurs due to bacteria that have managed to enter the udder via the teat sphincter and teat canal. The teat skin, the teat canal and the teat sphincter form the first – and most important – line of defence (Neijenhuis, 2004).
Cerqueira, J. L., Araújo, J. P., Cantalapiedra, J., & Blanco-Penedo, I. (2018). How is the association of teat-end severe hyperkeratosis on udder health and dairy cow behavior? Revue de Medecine Veterinaire, 169(1–2), 30–37.
Hillerton, J. E., Pankey, J. W., & Pankey, P. (2002). Effect of over-milking on teat condition. Journal of Dairy Research, 69(1), 81–84. https://doi.org/10.1017/S0022029901005386
Neijenhuis, F. (2004). Teat condition in dairy cows [Utrecht University]. https://edepot.wur.nl/1071
Neijenhuis, F., De Koning, K., Barkema, H., & Hogeveen, H. (2001). Physiological and Technical Aspects of Machine Milking. In A. Rosati, S. Mihina, & C. Mosconi (Eds.), The effects of machine milking on teat condition (pp. 33–40). ICAR, Villa del Ragno, Via Nomentana 134, 00162 Rome, Italy. https://www.icar.org/wp-content/uploads/2015/09/tec_series_07_nitra.pdf
Zucali, M., Reinemann, D. J., Tamburini, A., & Bade, R. D. (2008). Effects of liner compression on teat-end hyperkeratosis. American Society of Agricultural and Biological Engineers Annual International Meeting 2008, ASABE 2008, 3, 1854–1861. https://doi.org/10.13031/2013.24904