Salmonella Typhimurium persistence in a Hunter Valley dairy herd.

OBJECTIVE: An epidemiological study was undertaken at a Hunter Valley dairy with persistent Salmonella Typhimurium infection. The aim of the study was to identify cattle currently or previously infected with Salmonella, possible sources of the organism, patterns of spread, and husbandry practices that could be improved. METHODOLOGY: Faecal samples, feed, water and environmental samples were cultured for Salmonella and blood samples were tested for antibodies against Salmonella (Dublin and Typhimurium). A questionnaire was designed to identify possible risk factors associated with Salmonella excretion. RESULTS: S Typhimurium was apparently introduced from an old to a new dairy through manure spread as fertiliser. Salmonella apparently persisted in the effluent pond, and the following year clinical cases occurred after pasture, irrigated with water from the pond, was grazed by dry cows, and adult cattle became clinically ill with salmonellosis. The disease spread to other cows and calves. Poor design of calf pens assisted spread of Salmonella from sick to healthy calves. In addition, there was suspected transmission to the dairy farmer's 9-month-old daughter. Salmonellosis on a farm is a potential zoonotic risk to farm workers and their families. There is also the risk that cull cows may carry Salmonella to the abattoir and subsequently into the human food chain. Methods of waste management, and the design of calf pens, were identified as major risk factors that could be improved to minimise the spread of salmonellosis on this property.

Glutathione S-transferase activity and glutathione S-transferase mu expression in subjects with risk for colorectal cancer.

The glutathione S-transferases (alpha, mu, and pi), a family of Phase II detoxication enzymes, play a critical role in protecting the colon mucosa by catalyzing the conjugation of dietary carcinogens with glutathione. We investigated the efficacy of using the glutathione S-transferase (GST) activity of blood lymphocytes and GST-mu expression as biomarkers of risk for colorectal cancer. GST activity was measured in the blood lymphocytes of control individuals (n = 67) and in the blood lymphocytes (n = 60) and colon tissue (n = 34) of individuals at increased risk for colon cancer. Total GST activity was determined spectrophotometrically with the use of 1-chloro-2,4-dinitrobenzene as a substrate. The ability to express the um subclass of GST was determined with the use of an ELISA. Although interindividual variability in the GST activity of blood lymphocytes was greater than 8-fold (range, 16.7-146.8 nmol/min/mg), the GST activity of blood lymphocytes and colon tissue within an individual was constant over time and was unrelated to sex, age, or race. The GST activity of blood lymphocytes from high-risk individuals was significantly lower than that of blood lymphocytes from control individuals (P < or = 0.004). No association was observed between the frequency of GST-mu phenotype and risk for colorectal cancer. Blood lymphocytes from high-risk individuals unable to express GST-mu had lower levels of GST activity than did those from control subjects with the GST-mu null phenotype; however, this difference was significant in male subjects only (P < or = 0.006). Analysis of paired samples of blood lymphocytes and colon tissue indicated a strong correlation between the GST activity of the two tissue types (Spearman's rank correlation, r = 0.87; P < or = 0.0001). The GST activity of blood lymphocytes may be used to identify high-risk individuals with decreased protection from this Phase II detoxication enzyme who may benefit from clinical trials evaluating GST modulators as chemopreventive agents for colorectal cancer. The GST activity of blood lymphocytes may also be used in colorectal cancer chemoprevention trials to monitor the responsiveness of colon tissue to regimens that modify Phase II detoxication enzymes.

Putative sporidesmin toxicity in an Eastern Grey kangaroo (Macropus giganteus).

A 2-year-old, captive, male Eastern Grey kangaroo (Macropus giganteus) died after progressive weight loss over a 4 week period. Biochemical analysis suggested hepatobiliary injury. At necropsy the liver was small, pale and firm. There were no abnormalities detected in other organs. Histopathological examination revealed a severe, diffuse, obliterative cholangiohepatopathy with advanced periportal fibrosis. This chronic hepatotoxicity was consistent with exposure to sporidesmin, the toxic metabolite in the spores of the fungus Pithomyces chartarum. Restricted grazing opportunities and heavy fungal pasture contamination may have precipitated sporidesmin toxicity in this animal. Sporidesmin toxicity has not previously been reported in this species.

Coccidiosis in common wombats (Vombatus ursinus).

Eimeria arundeli is a widespread coccidian parasite of the common wombat (Vombatus ursinus), and has been considered to be nonpathogenic. We describe disease in two captive juvenile wombats ascribed to infection with E. arundeli. One animal had diarrhea, the second had mucoid soft feces and lost weight over several weeks prior to death. Masses of coccidial gametocytes in hypertrophic cells in the lamina propria distended villi, causing grossly visible raised pale thickened regions over extensive areas of the mucosa of the small intestine in both animals. Neutrophils infiltrated affected mucosa, and there was an inflammatory exudate into the intestinal lumen in case one. In case two, neutrophils infiltrated the lamina propria of villi focally, crypts were distended by necrotic debris, and epithelium on villi was extremely attenuated. No bacterial pathogens were isolated from lung and intestine in case one; case two was not cultured. Oocysts consistent with E. arundeli were present in large numbers in floatations of diarrheic feces in both cases.

Diagnosis of bovine venereal campylobacteriosis by ELISA.

An enzyme-linked immunosorbent assay (ELISA) measuring IgA antibodies in the vaginal mucus was used to diagnose bovine venereal campylobacteriosis in 241 herds with infertility and abortions. The presence of the disease was confirmed on 84 farms (34.8%) and it was suspected on a further 27 farms (11.2%). The specificity of the ELISA was found to be 98.5% but in the absence of a reliable comparative test sensitivity can not be estimated. Vaccination against campylobacteriosis will not interfere with the IgA ELISA because only IgG is present in the vaginal mucus of vaccinates. Because of the possibility of false reactions caused by antibody fluctuations in individual cattle, the ELISA is best used as a herd test. It appears that at present the vaginal mucus IgA ELISA is the test of choice for the diagnosis of bovine venereal campylobacteriosis.

Enteritis associated with Yersinia pseudotuberculosis infection in a buffalo.

A week after transport a 4 month old buffalo calf developed diarrhoea. Its condition gradually deteriorated and it died. Necropsy revealed acute haemorrhagic enteritis and enlarged mesenteric lymph nodes. Haemorrhages and numerous microabscesses were detected in the lamina propria of the small intestine associated with colonies of Gram negative bacteria. Yersinia pseudotuberculosis was isolated from the small intestine and from mesenteric lymph node. Enteritis caused by Y pseudotuberculosis does not appear to have been reported previously in buffalo in Australia.

Diagnosis by ELISA of bovine abortion due to Campylobacter fetus.

An enzyme-linked immunosorbent assay (ELISA) was developed to detect antigen-specific secretory IgA antibody in bovine vaginal mucus after abortion due to Campylobacter fetus subsp venerealis. Abortions were diagnosed by isolating the organism from 8 foetuses and/or foetal membranes and by histopathology. Vaginal mucus was collected from 7 cows shortly after abortion. All showed a high level of IgA antibody in their vaginal mucus when they were compared with an uninfected control group. The new ELISA is simple and practical and provides a useful tool for diagnosis of bovine venereal campylobacteriosis.

Evaluation of a PCR assay for identification and differentiation of Campylobacter fetus subspecies.

OBJECTIVE: To evaluate a polymerase chain reaction assay for identification of Campylobacter fetus and differentiation of the defined subspecies. DESIGN: Characterisation of bacterial strains by traditional phenotyping, polymerase chain reaction, a probabilistic identification scheme and macrorestriction profiling using pulsed field gel electrophoresis. PROCEDURE: The results of identification of 99 bacterial strains as determined by conventional phenotyping or by polymerase chain reaction were compared. Two of these were type strains of C fetus subsp fetus and C fetus subsp venerealis; the remaining strains were field isolates putatively identified as C fetus. In cases where the subspecies identity was disputed, isolates were identified by means of a probabilistic identification scheme and by macrorestriction profiling. RESULTS: The agreement between strain identities initially suggested by traditional phenotypic methods and the PCR assay was found to be 80.8%. The polymerase chain reaction proved to be a reliable technique for the species and subspecies identification of C fetus; equivocal results were obtained in only two instances. Initial misidentifications by conventional phenotyping methods were attributed to methodological differences used in various laboratories. CONCLUSION: Our results indicate that misidentification of C fetus in routine diagnostic laboratories may be relatively common. The PCR assay evaluated gave rapid and reproducible results and is thus a valuable adjunctive method for the identification of C fetus and subsequent subspecies differentiation.

Mastitis, polyarthritis and abortion caused by Mycoplasma species bovine group 7 in dairy cattle.

OBJECTIVE: To report an outbreak of mastitis, polyarthritis and abortion caused by Mycoplasma sp bovine group 7 in three large, centrally-managed dairies and to review the relevant literature. DESIGN: Epidemiological, clinical and laboratory data were analysed, collated and reported. Multidisciplinary procedures were employed. These included clinical assessment and comprehensive laboratory investigations of affected calves, aborted foetuses and milk samples. Mycoplasma cultures and genetic analyses of isolates were undertaken to identify the aetiological agent. RESULTS: About 30% of 240 calves usually kept in a calf rearing facility developed severe polyarthritis as a result of Mycoplasma sp bovine group 7 infection between 2 and 3 weeks of age. Multiple abortions occurred on these farms. Mycoplasma sp bovine group 7 was recovered from the fibrinopurulent synovial exudates of four 14-day-old calves, from the stomach contents and lungs of two aborted foetuses, from 14 of 21 bulk milk and four of 10 mastitic quarters. Three bulk colostrum samples cultured during the outbreak were negative for mycoplasma. CONCLUSION: Mycoplasma sp bovine group 7 caused significant economic losses as a result of polyarthritis, abortion and mastitis. The disease probably originated from udder infections with spread being facilitated by the decreased use of tetracycline in the treatment of mastitis. Neonatal calves were most likely infected by the consumption of milk contaminated with the organism. Abortions presumably resulted from mycoplasmaemia. This appears to be the first report in Australia of bovine abortion resulting from Mycoplasma sp infection.

Pathological changes in horses dying with equine influenza in Australia, 2007.

Analysis of pathology results from the 2007 equine influenza (EI) outbreak in Australia indicate that young foals in naïve horse populations are prone to developing broncho-interstitial pneumonia, and that this can be a rare manifestation of EI virus infection in mature horses. All horses may develop secondary bacterial bronchopneumonia, with mature horses more likely to die. EI outbreaks among heavily pregnant mares can result in increased neonatal losses because of premature placental separation and dystocia causing fetal hypoxia.

Health care strategies to promote earlier presentation of symptomatic breast cancer: perspectives of women and family physicians.

BACKGROUND: Many women with symptoms suggestive of a breast cancer diagnosis delay presentation to their family physician. Although factors associated with delay have been well described, there is a paucity of data on strategies to mitigate delay. OBJECTIVES: We conducted a qualitative research project to examine factors related to delay and to identify health care system changes that might encourage earlier presentation. METHODS: Individual semi-structured interviews were conducted with women who sought care 12 weeks or more after self-detection of breast cancer symptoms and with family physicians whose practices included patients meeting that criterion. RESULTS: The women and physicians both suggested a need for clearer screening mammography guidelines for women 40-49 years of age and for better messaging concerning breast awareness. The use of additional hopeful testimonials from breast cancer survivors were suggested to help dispel the notion of cancer as a "death sentence." Educational initiatives were proposed, aimed at both increasing awareness of "non-lump" breast cancer symptoms and advising women that a previous benign diagnosis does not ensure that future symptoms are not cancer. Women wanted empathic nonjudgmental access to care. Improved methods to track compliance with screening mammography and with periodic health exams and access to a rapid diagnostic process were suggested. CONCLUSIONS: A list of "at-risk situations for delay" in diagnosis of breast cancer was developed for physicians to assist in identifying women who might delay. Health care system changes actionable both at the health policy level and in the family physician's office were identified to encourage earlier presentation of women with symptomatic breast cancer.

Treating fatigue.

Fatigue is recognized as one of the most disabling and common symptoms of MS. However, no universal consensus has been reached regarding a formal definition for fatigue, and its mechanisms and causes are not understood. This review summarizes important research in this field and recommends a multidisciplinary approach to managing MS patients with fatigue. Such an approach should include proven pharmaceutical and non-pharmaceutical treatments.

Varied protein intake alters glutathione metabolism in rats.

We tested the possibility that protein consumption greater than needed for optimum growth of young adult rats might increase either their hepatic glutathione (GSH) content or plasma GSH turnover. Additional aims were to characterize the relationship between hepatic GSH content and plasma turnover under physiologic conditions and to evaluate the ability of values obtained by noninvasive blood sampling to accurately predict hepatic GSH content. Male Sprague-Dawley rats (300 g) were adapted to purified diets containing 0, 5, 10, 20 or 40% casein. Plasma GSH and amino acid concentrations, hepatic GSH content and [35S]GSH-determined plasma GSH turnover were measured in the anesthetized, intact animals. As dietary protein increased from 0 to 20% casein, liver weight and liver GSH concentration (mumol/g wet wt) both increased. In rats fed the 40% casein diet, liver weight increased even further while liver GSH concentration decreased, with the net result that total liver GSH content of the 40% casein-fed group was not significantly different from that of the 20% casein-fed group. Plasma urea, cysteine, methionine and GSH concentrations increased with increasing protein intake, but with the exception of plasma urea, which increased by 60%, there was no further increase at the 40% casein level. Plasma GSH turnover also increased as dietary casein increased from 0 to 20% but was not significantly increased further by the 40% casein diet. A sigmoid function best described the relationship between plasma GSH turnover and hepatic GSH content (r = 0.80, P less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)