Germicidal persistence of teat dips by modified excised teat procedure

Area of Science:

• Veterinary Science
• Microbiology
• Dairy Science

Background:

• Effective teat dips are crucial for controlling mastitis in dairy cattle.
• Assessing the persistence of germicidal activity is vital for teat dip efficacy.

Purpose of the Study:

• To evaluate the 8-hour germicidal activity persistence of five different teat dip formulations.
• To compare the efficacy of teat dips against Escherichia coli and Klebsiella oxytoca.

Main Methods:

• An excised teat protocol was adapted to test teat dip germicidal activity over an 8-hour period.
• Five teat dip formulations (iodophor, chlorhexidine gluconate, linear dodecyl benzene sulfonic acid, sodium chlorite-lactic acid in water, and sodium chlorite-lactic acid in gel) were tested.
• Activity was assessed against Escherichia coli and Klebsiella oxytoca.

Main Results:

• Iodophor and chlorhexidine demonstrated high germicidal activity throughout the 8-hour test period.
• Linear dodecyl benzene sulfonic acid showed minimal activity.
• Sodium chlorite-lactic acid dips had high initial activity that declined over time, with the gel base outperforming the water base.
• Chlorhexidine was less effective against Klebsiella oxytoca, while the gel base dip was more effective against this pathogen compared to Escherichia coli.

Conclusions:

• The modified excised teat assay is a useful tool for screening teat dips for germicidal persistence.
• Iodophor and chlorhexidine offer sustained germicidal activity, while formulation base impacts the persistence of sodium chlorite-lactic acid dips.