Objective—To evaluate shedding patterns of Staphylococcus aureus, specifically the association between clonal relatedness and shedding patterns of S aureus for cows with naturally occurring S aureus intramammary infection.
Design—Longitudinal field study.
Sample—Milk samples from 22 lactating cows (29 mammary glands) of varied numbers of lactations on 2 dairies.
Procedures—Foremilk samples were collected weekly for 26 to 44 weeks during lactation from individual mammary glands. Milk samples were cultured bacteriologically with a 0.01-mL inoculum. Samples were considered culture positive for S aureus if ≥ 1 colony-forming units were obtained. Milk samples from known S aureus–positive mammary glands that were culture negative for S aureus or culture positive with a single colony of S aureus were cultured bacteriologically a second time with a 0.1-mL inoculum. Longitudinal shedding patterns of S aureus and the effect of strain type on ln(colony forming unit count) were examined.
Results—With the 0.01-mL inoculum, 914 of 1,070 (85%) samples were culture positive. After reculturing of negative samples with a 0.1-mL inoculum, 1,011 (95%) of the samples were culture positive. There was no significant difference in the detection of S aureus between genotypic clusters when either the 0.01- or 0.1-mL inoculum was used. There was no significant difference in the amount of shedding between mammary glands infected with isolates in genotypic cluster 1 or 2. No consistent shedding patterns were identified among or within cows. There was a significant difference in mammary gland linear score and test day (composite) linear score between mammary glands infected with isolates in genotypic clusters 1 and 2.
Conclusions and Clinical Relevance—S aureus was shed consistently in cows with naturally occurring intramammary infection in cows, and regardless of the pulsotype, variations in the amount of S aureus shedding had no significant effect on the ability to detect S aureus with a 0.1-mL inoculum.
To determine whether exposure to UV germicidal irradiation (UVGI) reduces concentrations of viable aerosolized microorganisms (attenuated strains of common veterinary pathogens) in a simulated heating, ventilation, and air conditioning (HVAC) system.
42 air samples seeded with bacteriophage MS2 or attenuated strains of Bordetella bronchiseptica, feline calicivirus, feline herpesvirus-1, canine parvovirus, or canine distemper virus (6/microorganism) or with no microorganisms added (6).
A simulated HVAC unit was built that included a nebulizer to aerosolize microorganisms suspended in phosphate-buffered water, a fan to produce airflow, 2 UVGI bulb systems, and an impinger for air sampling. Ten-minute trials (3 with UVGI, 3 without UVGI, and 1 negative control) were conducted for each microorganism. Impingers collected microorganisms into phosphate-buffered water for subsequent quantification with culture-based assays. Results for samples yielding no target microorganisms were recorded as the assay's lower limit of detection. Statistical analysis was not performed.
The UVGI treatment resulted in subjectively lower concentrations of viable MS2, B bronchiseptica, and canine distemper virus (arithmetic mean ± SD log10 microorganism reduction, 2.57 ± 0.47, ≥ 3.45 ± 0.24, and ≥ 1.50 ± 0.25, respectively) collected from air. Feline herpesvirus-1 was detected in only 1 sample without and no samples with UVGI treatment. Feline calicivirus and canine parvovirus were not detectable in any collected samples.
CONCLUSIONS AND CLINICAL RELEVANCE
Results for some surrogates of veterinary pathogens suggested a potential benefit to supplementing manual disinfection practices with UVGI-based air cleaning systems in animal care environments. Further research is needed to investigate the utility of UVGI in operating HVAC systems.
Objective—To identify and evaluate coping strategies advocated by experienced animal shelter workers who directly engaged in euthanizing animals.
Sample Population—Animal shelters across the United States in which euthanasia was conducted (5 to 100 employees/shelter).
Procedures—With the assistance of experts associated with the Humane Society of the United States, the authors identified 88 animal shelters throughout the United States in which animal euthanasia was actively conducted and for which contact information regarding the shelter director was available. Staff at 62 animal shelters agreed to participate in the survey. Survey packets were mailed to the 62 shelter directors, who then distributed them to employees. The survey included questions regarding respondent age, level of education, and role and asked those directly involved in the euthanasia of animals to provide advice on strategies for new euthanasia technicians to deal with the related stress. Employees completed the survey and returned it by mail. Content analysis techniques were used to summarize survey responses.
Results—Coping strategies suggested by 242 euthanasia technicians were summarized into 26 distinct coping recommendations in 8 categories: competence or skills strategies, euthanasia behavioral strategies, cognitive or self-talk strategies, emotional regulation strategies, separation strategies, get-help strategies, seek long-term solution strategies, and withdrawal strategies.
Conclusions and Clinical Relevance—Euthanizing animals is a major stressor for many animal shelter workers. Information regarding the coping strategies identified in this study may be useful for training new euthanasia technicians.