An outbreak of mastitis in a dairy herd due to Pseudomonas aeruginosa contamination of dry-cow therapy at manufacture

Pseudomonas mastitis in a dairy herd

“…Peracute cases of mastitis caused by Pseudomonas have been reported previously, [3][4][5] but there has only been one report of gangrenous mastitis associated with P aeruginosa. 7 This occurred in a single cow 2 days after dry cow therapy and was associated with severe systemic signs, collapse and lack of response to treatment.…”

“…Lack of response to tetracycline and streptomycin has been noted by others. [2][3][4] It is not possible to comment on the value of neomycin and gentamycin as only one cow was treated with each drug. In this outbreak, the cow treated with gentamycin survived, but was less severely affected than the other cows.…”

“…This test and slaughter program has been advocated in other outbreaks because of poor response to antibiotic therapy, persistence of the organism in the udder, and the probability of lateral transmission. [2][3][4] Similarly, subclinical infections were eliminated from this herd by culling for slaughter all cows identified as infected, particularly by composite quarter milk sampling and culture at the time of drying off. The suitability of milk sampling cows at drying off for control purposes has also been advocated elsewhere.…”

“…The University of Queensland, Queensland 4072 M astitis in cattle caused by Pseudomonas aeruginosa is uncommon and outbreaks are usually associated with contaminated udder washing water or contaminated intramammary dry-cow preparations. [1][2][3][4] Mastitis caused by P aeruginosa associated with contaminated dry-cow preparations has been reported in nonlactating cows but occurs more commonly immediately after calving and is frequently peracute in nature. 3,4 Mastitis associated with contaminated udder-washing preparations occurs throughout lactation and may be peracute, acute or, less commonly, subclinical.…”

“…[1][2][3][4] Mastitis caused by P aeruginosa associated with contaminated dry-cow preparations has been reported in nonlactating cows but occurs more commonly immediately after calving and is frequently peracute in nature. 3,4 Mastitis associated with contaminated udder-washing preparations occurs throughout lactation and may be peracute, acute or, less commonly, subclinical. 5,6 Gangrenous mastitis associated with P aeruginosa was recently reported in a cow immediately following dry-cow intramammary treatment.…”