Effect of Pre-Milking Teat Foam Disinfection on the Prevention of New Mastitis Rates in Early Lactation.

The objective of this study was to determine the benefit of pre-milking teat foam disinfection on the prevention of new infections by contagious and environmental bacteria in two spring calving herds managed outdoors (Herd 1 [H1]; 331 cows and Herd 2 [H2]; 142 cows). Four pre-milking teat preparation treatments were applied post calving; with each herd receiving two treatments; using a split udder design (for approx. 15 weeks). These treatments included; (1) 'water wash, foam application and dry wipe (WFD) in H1'; (2) 'water wash and dry wipe (WD)' in H1; (3) 'foam application and dry wipe (FD)' in H2; (4) 'no teat cleaning preparation (NP)' in H2. Individual quarter foremilk samples were collected on four occasions and all clinical and sub-clinical cases were recorded. The mean SCC of quarter foremilk samples was 134 × 103 cells/mL and 127 × 103 cells/mL for WD and WFD, respectively, and 109 × 103 cells/mL and 89 × 103 cells/mL for NP and FD, respectively (p > 0.05). Lower bacterial counts were observed on teat skin that received a foaming treatment. Pre-milking teat disinfection using a foaming product may be of little benefit, in early lactation, for a pasture-based dairy herd.

The effect of disinfectant ingredients on teat skin bacteria associated with mastitis in Irish dairy herds.

BACKGROUND: Teat disinfection is an important step in the control of mastitis within a dairy herd. The objective of this study was to evaluate the effectiveness of 96 commercially available teat disinfectant products in Ireland against bacterial isolates on teat skin. Teat disinfection products were applied to the teats of seventeen Holstein-Friesian cows. A split-udder model was used where one cow received two different teat disinfection products on each day. A composite swab sample was taken of the left teats and the right teats before and after teat disinfectant application. Swab samples were plated onto 3 different selective agars to enumerate bacterial counts of streptococcal, staphylococcal and coliform isolates. RESULTS: Streptococcal isolates were the most prominent bacterial group recovered on teat swabs taken before the application of a teat disinfection product (55.0%), followed by staphylococcal isolates (41.3%) and coliform isolates (3.7%). Products were reclassified by active ingredients (n = 9) for analysis. These ingredient groups included; chlorhexidine, chlorine dioxide, diamine, iodine, iodine and lactic acid, lactic acid, lactic acid and chlorhexidine, lactic acid and hydrogen peroxide, and lactic acid and salicylic acid. The ingredient group, chlorine dioxide, resulted in comparable reductions to the iodine group for streptococcal isolates. The ingredient group, iodine combined with lactic acid, resulted in the greatest reduction of staphylococcal isolates. When observing products individually, a product containing 1.6% w/w lactic acid combined with hydrogen peroxide was the most effective at reducing streptococcal isolates on the teat skin, whereas a product containing lactic acid combined with 0.6% w/w chlorhexidine was the most effective against staphylococcal isolates. Minor differences were observed regarding the relationship between effectiveness and active ingredient concentration between products. CONCLUSIONS: This study suggests that some teat disinfectant products achieve a higher reduction in bacterial levels against different specific bacterial groups on teat skin than other products. Therefore, when choosing a teat disinfectant product, the bacteria in the dairy herds' environment should be considered. Further studies are necessary to evaluate products efficacy against new IMIs and any possible effects on teat skin condition.

Screening commercial teat disinfectants against bacteria isolated from bovine milk using disk diffusion.

BACKGROUND AND AIM: Teat disinfection is an important tool in reducing the incidence of bovine mastitis. Identifying the potential mastitis-causing bacterial species in milk can be the first step in choosing the correct teat disinfectant product. The objective of this study was to screen commercial teat disinfectants for inhibition against mastitis-associated bacteria isolated from various types of milk samples. MATERIALS AND METHODS: Twelve commercially available teat disinfectant products were tested, against 12 mastitis-associated bacteria strains isolated from bulk tank milk samples and bacterial strains isolated from clinical (n=2) and subclinical (n=3) quarter foremilk samples using the disk diffusion method. RESULTS: There was a significant variation (7-30 mm) in bacterial inhibition between teat disinfection products, with products containing a lactic acid combination (with chlorhexidine or salicylic acid) resulting in the greatest levels of bacterial inhibition against all tested bacteria (p<0.05). CONCLUSION: In this study, combined ingredients in teat disinfection products had greater levels of bacterial inhibition than when the ingredients were used individually. The disk diffusion assay is a suitable screening method to effectively differentiate the bacterial inhibition of different teat disinfectant products.

Are some teat disinfectant formulations more effective against specific bacteria isolated on teat skin than others?

The use of pre- and post-milking teat disinfectants can reduce teat bacterial load and aid in the collection of high-quality milk. The objective of this study was to compare the reduction in bacteria populations on teat skin after the application of different commercial teat disinfectant products. Ten teat disinfectant products were applied to the teats of 10 Holstein-Friesian cows. One cow received one teat disinfectant product at each sampling point before cluster application for milking. A composite swab sample was taken of the 4 teats of each cow before and after teat disinfectant application. Swab samples were placed on three different selective agars to enumerate bacterial counts of staphylococcal, streptococcal and coliforms isolates on teat skin. Staphylococcal isolates were the most prominent bacterial group recovered on teat swabs (49%), followed by streptococcal (36%) and coliform (15%) isolates before the application of disinfectant. The average bacterial reductions on teat skin were shown to be 76%, 73% and 60% for staphylococcal, streptococcal and coliform isolates, respectively. All of the teat disinfectant products tested reduced teat bacterial load for all three bacterial groups. Product 4 containing 0.6% w/w diamine was the most effective against bacterial populations of staphylococcal and streptococcal isolates on teat skin with a reduction of 90% and 94%, respectively. Whereas product 10, which contained 0.5% w/w iodine, resulted in the highest reduction in coliforms on teat skin with a reduction of 91%. Results from this study suggest that specific bacterial population loads on teats can be reduced using different teat disinfectant formulations.

Utilized friction when entering and exiting a dry and wet bathtub.

Bathtubs and showers are a common source of unintentional slips and falls. The goal of this study was to quantify the friction used by barefoot subjects entering and exiting a typical bathtub/shower enclosure under dry and wet conditions. Sixty subjects (30F, 30M) from three age groups (20-30 years, 40-50 years, 60-70 years) entered and exited a slip-resistant bathtub using six movement patterns (three entering and three exiting the tub) simulating actual use. Force plates installed in the tub floor and the slip-resistant deck outside the tub measured ground reaction forces, from which utilized friction and double support times were calculated. Overall, utilized friction varied from 0.102 to 0.442 (0.235+/-0.057) and was 0.058+/-0.040 lower in wet than dry conditions across all movement patterns (p<0.0001). During tub exiting movements, older subjects used less friction than young subjects (p<0.006). Utilized friction did not vary between genders (p>0.14). Double support times were longer in older subjects than in both young and middle-aged subjects for all movement patterns (p<0.0009) and longer under wet than dry conditions for all entry movements (p<0.0001). These data suggest that subjects regard the wet condition as more hazardous than the dry condition and adapt their utilized friction accordingly. These data also show that older subjects are more cautious than young subjects when confronted with the dual tasks of stepping over the tub's apron and transitioning to a surface perceived to be more slippery.

Validation of walkway tribometers: establishing a reference standard.

Tribometers are mechanical devices used to measure walkway coefficient of friction (COF) for the purpose of assessing slip risk. The purpose of this study was to define a tribometer reference standard and use it to assess the performance of various tribometers. Eighty subjects were randomly assigned to walk across one of four wet walkway surfaces (polished black granite, porcelain, vinyl composition tile, and ceramic tile) to establish the relative slipperiness of each surface. Eleven tribometers were subsequently used to measure and rank the COF of all four surfaces. Our results revealed that only four of the 11 tribometers (Wessex pendulum, Sigler pendulum, Mark II, and Mark III) met our compliance criteria by both correctly ranking all four surfaces and differentiating between surfaces of varying degrees of slipperiness. Our protocol demonstrates that human gait-based measures of slipperiness can be used to create reference standards against which tribometer measurements can be validated.

Efficacy of a teat dip containing the bacteriocin lacticin 3147 to eliminate Gram-positive pathogens associated with bovine mastitis.

On most dairy farms teat dips are applied to the teats of cows either before or after milking in order to prevent pathogens from gaining access to the mammary gland via the teat canal. In the present experiments, a natural teat dip was developed using a fermentate containing the live bacterium Lactococcus lactis DPC 3251. This bacterium produces lacticin 3147, a two-component lantibiotic which was previously shown to effectively kill Gram-positive mastitis pathogens. Lacticin 3147 activity in the fermentate was retained at 53% of its original level following storage for 3 weeks at 4 degrees C. In the initial experiments in vitro, 105 colony-forming units/ml (cfu/ml) of either Staphylococcus aureus, Streptococcus dysgalactiae or Streptococcus uberis were introduced into the lacticin-containing fermentate. Neither Staph. aureus nor Str. dysgalactiae could be detected after 30 min or 15 min, respectively, while Str. uberis was reduced approximately 100-fold after 15 min. Following these trials, preliminary experiments were performed in vivo on teats of lactating dairy cows. In these experiments, teats were coated with each of the challenge organisms and then dipped with the lacticin-containing fermented teat dip. Following a dip contact time of 10 min, staphylococci were reduced by 80% when compared with the undipped control teat. Streptococcal challenges were reduced by 97% for Str. dysgalactiae and by 90% for Str. uberis. These trials showed that the teat dip is able to reduce mastitis pathogens on the teats of lactating cows.

Assessment of walkway tribometer readings in evaluating slip resistance: a gait-based approach.

The purpose of this study was to assess the viability of using slip risk (as quantified during human subject walking trials) to create a reference standard against which tribometer readings could be compared. First, human subjects (N=84) were used to rank objectively the slipperiness of three different surfaces with and without a contaminant (six conditions). Second, nine tribometers were used to independently measure and rank surface slipperiness for all six conditions. The slipperiness ranking determined from the walking trials was considered the reference against which the tribometer measurements were compared. Our results revealed that only two of the nine tribometers tested (Tortus II and Mark III) met our compliance criteria by both correctly ranking all six conditions and differentiating between surfaces of differing degrees of slipperiness. These findings reinforce the need for objective criteria to ascertain which tribometers effectively evaluate floor slipperiness and a pedestrian's risk of slipping.