Monthly Archives: July 2018

Strategies for reducing mastitis in fresh heifers

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Are too many heifers on your farm showing up with mastitis early in that first lactation? You may want to examine your prevention strategies. A review paper that examined the effectiveness of various precalving treatments in heifers was published earlier this summer. Here are the key take-a-ways:

developing udder on a Jersey heifer
She’ll be in the parlor soon.
photo: Spirited Rose Homestead Dairy Farm
  • When the infection is caused by contagious bacteria (e.g., Streptococcus agalactiae, Staphylococcus aureus), antibiotics, teat sealants, and vaccines can improve udder health outcomes.
  • Particularly if you are considering using antimicrobial treatments, culture quarter milk so you know who the enemy is. We want to minimize the development of antibiotic resistance.
  • When environmental pathogens (e.g., Escherichia coli, non-agalactiae streptococci) are the problem, teat sealants and combination therapies are effective at reducing mastitis risk.
  • When coagulase-negative staphs (CNS) are infecting heifer udders, antibiotics, teat-sealants, and combination therapies offer the most help.
  • When employing any of these treatment options, be sure they are delivered by a well-trained person.
  • On farms with effective fly control and that minimize stress for late-gestation heifers, there may be little benefit from preventative medical treatment.

The paper: Naqvi, Nobrega, Ronksley, & Barkema. June 2018. Effectiveness of precalving treatment on postcalving udder health in nulliparous dairy heifers: A systematic review and meta-analysis. Journal of Dairy Science 101:4707-4728.

Another good resource is the National Mastitis Council’s Heifer Mastitis Prevention and Control Plan.

OSU Research: Predicting post-calving clinical mastitis in dry cows via serum profile

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Researchers from Oregon State University investigated the blood serum profiles of Holstein cows before and after calving and compared those that developed clinical mastitis with those that did not. To do so, they used ultra-performance liquid chromatography high resolution mass spectrometry plus statistics to identify differences in concentration of metabolites, lipids, minerals, and inflammatory markers in blood serum. It’s OK if you read that last sentence and went, “Huh?”  The short version is that they ran blood serum samples from dry cows through some fancy laboratory equipment to see if there were any indicators associated with developing clinical mastitis after calving. And yes, there are!

For example, alpha-tocopherol (a form of vitamin E) levels were significantly higher in the blood of cows that did not develop clinical mastitis compared to those that did (Figure 1). Another difference was in the overall profile of metabolites (molecules that participate in or are produced during metabolism); they were quite different for cows that remained healthy and those with post-calving mastitis (Figure 2).

Figure 1. Control animals (no mastitis; open bars) had significantly more alpha-tocopherol (vitamin E) in their blood than cows that developed mastitis (shaded bars). From Figure 4 from Zandkarimi et al. 2018.
The figure shows self-organizing map of metabolomic data.
Figure 2. See the starkly different profiles in serum metabolite concentration between cows that developed mastitis post-calving (CMP) and those that did not (Control)? The metabolites are grouped by metabolite family, e.g., carnitines. The more red colors indicate higher concentrations, while blue indicates lower. From Figure 5 from Zandkarimi et al. 2018.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

While no dairies have liquid chromatography mass spec technology in their on-farm lab, these results may lead the way to identifying one or two highly reliable blood markers that could be easily measured on the dairy. And forewarned is forearmed, right? Knowing which cows were likely to develop mastitis could allow proactive treatment to prevent the more expensive and damaging clinical mastitis.

The paper: F. Zandkarimi, J. Vanegas, X. Fern, C.S. Maier, G. Bobe. Metabotypes with elevated protein and lipid catabolism and inflammation precede clinical mastitis in prepartal transition dairy cows. Journal of Dairy Science, June 2018, 101:5531–5548