Biofilm and their role in udder health

Biofilms have been present on earth for around 3.4 billion years and are the most successful and widely distributed form of life on earth (Westall et al. 2001). Their characteristics make them unique and they take a central role in microbial evolution and adaptation. These characteristics have been acquired through billions of years of evolutionary adaptation. This is what makes them successful in their survival strategy. The survival and existence of a wide range of microorganisms is due to biofilm formation, which is a microbial defense mechanism to ensure the survival of the bacteria. This causes resistance to regular and traditional methods, with adverse effects on animal health. We would like to tell you more about how biofilm formation affects animal health and how they pose a challenge to udder health in particular.

Biofilms can colonize a large variety of biological or non-biological surfaces (Hall-Stoodley et al., 2004). The ideal biological conditions for bacteria to be successful include enough nutrients, humidity, and a suitable temperature. Thus, animals are a perfect host for bacterial colonization and biofilm formation, which can be potentially harmful for the animal. It was not until the 1990’s that biofilms were investigated in relation to persistent or re-occurring health challenges (Melchior et al. 2006). According to the National Institute of Health we know now that approximately 80% of the microbial challenges have a biofilm related ethology (NIH, 2002).

A notorious health challenge in dairy cattle is within the udder. Microorganisms are the main cause of udder health challenges in cows and the ability of bacteria to produce biofilms is considered an important virulent property in the pathogenesis (FELIPE, et al., 2017). Knowledge about biofilm will change the approach needed to tackle these challenges, which affects the mechanisms of functioning bacterial communities in the form of biofilms. Therefore, it is necessary to search for effective methods that would influence the bacteria in biofilms to take a more proactive approach when it comes to dealing with udder health problems.

The formation of biofilm

Biofilms are clusters of microbes enclosed in a self-produced matrix, like a protective layer. They appear in a 3D microbial structure and vary widely in shape and size. There is not a single type of biofilm, they will depend on the type of microbes forming them in combination with all possible influences coming from the environment. Biofilm-associated bacteria show an innate resistance to traditional methods, disinfectants, and the animals immune system. Bacteria in biofilm are 100-1000 times less susceptible to traditional methods compared to free floating bacteria of the same strain (Donlan, 2000). This bacterial persistence, through the formation of biofilm, is responsible for resistance and often the root of recurrent challenges.

Biofilm can be formed within 24 hours after attachment. Bacteria form biofilms in response to environmental stresses such as a compromised immune system, drying off or calving. There are five main steps for the formation and spreading of biofilms (see figure 1). After the attachment phase, the bacteria will start to form a (mono)layer and produce a polymeric matrix layer for protection. In the last stage, some cells or parts of the mature biofilm start to detach and disperse into the environment as planktonic cells again. They can then start to form a new cycle of biofilm formation elsewhere in the animal (Guzmán-Soto et al., 2021). Biofilm formation can take place in the background for an exceptionally long time without affecting the cow. This can change during stress periods, where the bacteria within the bacteria can launch an attack on the cow.

Location of biofilm formation

Outer and inner surfaces of animals are ideal hosts for microbial colonization. However, microbes face different environmental challenges when entering the body, which threaten their odds of survival and reduce their chances of successful colonization. Biofilm formation is a survival strategy to withstand these challenges to ensure the bacteria remain. Research has shown that biofilm production is an important mechanism used by unfavorable bacteria in causing udder health challenges (Gomes et al., 2016). The presence of biofilms in mammary glands results in a decreased probability in the success of traditional methods when trying to tackle arising health issues in lactating cattle.

Factors involved in the development and persistence of udder health challenges

Udder health challenges and biofilm formationcan go unnoticed for a substantial period of time. It is important to realise that biofilm formation often begins in heifers but is in hiding as they haven’t gone through severe periods of stress yet. Heifers are often still high in energy with a well balanced immune system, so they can suppress challenges well. However, this can be the start for future issues and needs to be addressed in time.

Serious challenges will effect animal health and welfare, and is accompanied by decreased milk production, increased health care costs, higher culling rates and in the worst case, death (Melchior et al. 2006). The financial implications are significant, and much effort is needed to get ahead of udder health challenges, with mediocre results. This is largely due to the bacteria becoming resistant. Especially persistent challenges are difficult to tackle which hinders eradication. Age, parity, stage of lactation, position in the effected quarter and somatic cell counts (SCC) also play a role in the success rate (Sol et al., 1997). Lactating cows are more challenging and show lower success rates. That also applies to older cows or cows with high SCC counts. Persistent udder health challenges are often labelled as extremely difficult to resolve (Sol et al., 2000).

How to support cows during udder health challenges?

For increased chances of success, AHV developed the AHV Udder Health Program. To keep cows’ udder as healthy as possible, it is important to monitor the animal, preferably using (milk) data that provides additional insights. The key is to have a proactive attitude in keeping the animals healthy and in production, because the longer the udder remains healthy, the more the animals and the farmer will benefit. The AHV Udder Health Program is highly successful due to its patent pending AHV QSA Technology, which directly targets the biofilm formed in the udder by breaking it down and allowing the cows immune system to tackle the challenge at the source!

The AHV Udder Health Program

The AHV Udder Health Program identifies four categories*:

• UDR – C: A healthy udder
• UDR – L: Maximum. 2 issues regarding udder health in the last 18 months
• UDR – P: Maximum. 3 issues regarding udder health in the last 18 months
• UDR – R: More than 3 issues in the last 18 months

* Categories and attentions are based on Milk Recording data

Our research shows that for a significant improvement, it does not matter how much the somatic cell count deviates from the normal value. On average, almost 85% (see table) of the groups in which we recommend (UDR – L & P) administering a solution (AHV Quick, Extra, Aspi) show a positive result at the next Milk Recording. In the youngest animals, we even see a positive result in 9 out of 10 cows.

What are the benefits of optimal udder health?

Animals that are healthy produce optimally and require less intervention, resulting in these animals staying the herd longer. For the dairy farmer, this means a higher, and better-quality milk yield, and an overall healthier herd with higher production numbers over time. Underperforming animals are the main reason for replacement by younger, and therefore lower producing animals. Milk production and milk quality not meeting specific standards have a negative economic impact on a farm’s revenue. The importance of timely intervention is therefore essential to keep livestock healthy and to maintain a healthy financial situation.

At AHV, we learn more about biofilm every day

Biofilm formation is considered a selective advantage for unfavourable bacteria causing udder health challenges, facilitating bacterial persistence in the udder. Deeper knowledge of biofilm in relation to udder health challenges can help determine the most effective strategy to address these challenges in order to reduce losses and to ensure milk safety and quality. Therefore, at AHV, we are constantly investigating in our own research facility how to make our products even more effective.

Sources:

• Westall, F., de Wit, M. J., Dann, J., van der Gaast, S., de Ronde, C. E., & Gerneke, D. (2001). Early Archean fossil bacteria and biofilms in hydrothermally-influenced sediments from the Barberton greenstone belt, South Africa. Precambrian Research, 106(1-2), 93-116.
• Melchior, M. B., Vaarkamp, H., & Fink-Gremmels, J. (2006). Biofilms: a role in recurrent mastitis infections?. The Veterinary Journal, 171(3), 398-407.
• Hall-Stoodley, L., Costerton, J. W., & Stoodley, P. (2004). Bacterial biofilms: from the natural environment to infectious diseases. Nature reviews microbiology, 2(2), 95-108.
• Donlan, R. M. (2000). Role of biofilms in antimicrobial resistance. ASAIO journal, 46(6), S47-S52.
• Gomes, F., Saavedra, M. J., & Henriques, M. (2016). Bovine mastitis disease/pathogenicity: evidence of the potential role of microbial biofilms. FEMS Pathogens and Disease, 74(3), ftw006.
• Sol, J., Sampimon, O. C., Snoep, J. J., & Schukken, Y. H. (1997). Factors associated with bacteriological cure during lactation after therapy for subclinical mastitis caused by Staphylococcus aureus. Journal of dairy science, 80(11), 2803-2808.
• Owens, W. E., Nickerson, S. C., Boddie, R. L., Tomita, G. M., & Ray, C. H. (2001). Prevalence of mastitis in dairy heifers and effectiveness of antibiotic therapy. Journal of Dairy Science, 84(4), 814-817.
• Sol, J., Sampimon, O. C., Barkema, H. W., & Schukken, Y. H. (2000). Factors associated with cure after therapy of clinical mastitis caused by Staphylococcus aureus. Journal of dairy science, 83(2), 278-284.
• Parrilli, E., Tutino, M. L., & Marino, G. (2022). Biofilm as an adaptation strategy to extreme conditions. Rendiconti Lincei. Scienze Fisiche e Naturali, 1-10.