Does increasing milk yield per cow reduce greenhouse gas emissions? A system approach.

Milk yield per cow has continuously increased in many countries over the last few decades. In addition to potential economic advantages, this is often considered an important strategy to decrease greenhouse gas (GHG) emissions per kg of milk produced. However, it should be considered that milk and beef production systems are closely interlinked, as fattening of surplus calves from dairy farming and culled dairy cows play an important role in beef production in many countries. The main objective of this study was to quantify the effect of increasing milk yield per cow on GHG emissions and on other side effects. Two scenarios were modelled: constant milk production at the farm level and decreasing beef production (as co-product; Scenario 1); and both milk and beef production kept constant by compensating the decline in beef production with beef from suckler cow production (Scenario 2). Model calculations considered two types of production unit (PU): dairy cow PU and suckler cow PU. A dairy cow PU comprises not only milk output from the dairy cow, but also beef output from culled cows and the fattening system for surplus calves. The modelled dairy cow PU differed in milk yield per cow per year (6000, 8000 and 10 000 kg) and breed. Scenario 1 resulted in lower GHG emissions with increasing milk yield per cow. However, when milk and beef outputs were kept constant (Scenario 2), GHG emissions remained approximately constant with increasing milk yield from 6000 to 8000 kg/cow per year, whereas further increases in milk yield (10 000 kg milk/cow per year) resulted in slightly higher (8%) total GHG emissions. Within Scenario 2, two different allocation methods to handle co-products (surplus calves and beef from culled cows) from dairy cow production were evaluated. Results showed that using the 'economic allocation method', GHG emissions per kg milk decreased with increasing milk yield per cow per year, from 1.06 kg CO2 equivalents (CO2eq) to 0.89 kg CO2eq for the 6000 and 10 000 kg yielding dairy cow, respectively. However, emissions per kg of beef increased from 10.75 kg CO2eq to 16.24 kg CO2eq due to the inclusion of suckler cows. This study shows that the environmental impact (GHG emissions) of increasing milk yield per cow in dairy farming differs, depending upon the considered system boundaries, handling and value of co-products and the assumed ratio of milk to beef demand to be satisfied.

Sorbitol-fermenting enterohaemorrhagic Escherichia coli O157:H- causes another outbreak of haemolytic uraemic syndrome in children.

An outbreak of haemolytic uraemic syndrome (HUS) among children caused by infection with sorbitol-fermenting enterohaemorrhagic Escherichia coli O157:H- (SF EHEC O157:H-) occurred in Germany in 2002. This pathogen has caused several outbreaks so far, yet its reservoir and routes of transmission remain unknown. SF EHEC O157:H- is easily missed as most laboratory protocols target the more common sorbitol non-fermenting strains. We performed active case-finding, extensive exploratory interviews and a case-control study. Clinical and environmental samples were screened for SF EHEC O157:H- and the isolates were subtyped by pulsed-field gel electrophoresis. We identified 38 case-patients in 11 federal states. Four case-patients died during the acute phase (case-fatality ratio 11%). The case-control study could not identify a single vehicle or source. Further studies are necessary to identify the pathogen's reservoir(s). Stool samples of patients with HUS should be tested with an adequate microbiological set-up to quickly identify SF EHEC O157:H-.

[Health monitoring units in Bavaria. Concept, aims and thematic focus of the first survey on children's environment and health]. / Gesundheits-Monitoring-Einheiten (GME) in Bayern. Konzept, Ziele und thematische Schwerpunkte des 1. Surveys zu Umwelt und Gesundheit von Kindern.

Starting in 2004, health monitoring units (GME) were established in three rural and three urban regions of the federal state Bavaria, Germany. The GME s aim is to gain current and relevant health data especially of children in Bavaria and to evaluate health promotion and prevention strategies. The first survey 2004/2005 was a cross-sectional study of the environmental health of children aged 5 to 7 years. There are data available from 3030 girls and 3319 boys (response rate 78%). This paper describes the study regions and the sociodemographic characteristics of the study population which differed substantially between urban and rural regions. The thematic focus of the survey was: (1) Social disparities in housing conditions, related environmental exposures, and children's health, (2) accidents and injuries, (3) environmental tobacco smoke exposure of children and precautionary measures of their parents, (4) nutrition, physical activity and obesity, and (5) temporal trends of the prevalence of asthma and allergies. The insights gained within the health monitoring units will contribute to the identification and quantification of health risks as well as to the establishment of intervention strategies with special focus on the needs of the public health service.

[Accumulated occurrence of illnesses with Salmonella enteritidis in hospitals and nursing homes in the district Oberallgaeu, Bavaria, in July 2004]. / Gehäuftes Auftreten von Erkrankungen mit Salmonella Enteritidis in Krankenhäusern und Altenheimen im Landkreis Oberallgäu (Bayern) im Juli 2004.

We report on the investigation of a Salmonella enteritidis outbreak in hospitals and nursing homes in the district Oberallgaeu, Bavaria, in July 2004. Affected by this outbreak were hospital patients, inhabitants of nursing homes, kitchen coworkers and maintenance personnel. Within this outbreak six deaths were observed. A forensic medical investigation of four deaths revealed two cases of Salmonella enteritis as the primary cause of death, another cause of death was due to other causes and one cause of death remained unclear. The microbiological investigation of stool samples linked all positive samples to an outbreak during this period. The epidemiological outbreak curve pointed towards a foodborne transmission of the pathogen. The infection period could be limited to the weekend of the 3./4.7.2004. All affected institutions were supplied by a catering service with several sites. All tested food samples were negative for Salmonella enteritis. Epidemiological investigations revealed that a contaminated pudding was probably responsible for the outbreak.

[Risk factors for abundance of shiga toxin producing Escherichia coli in sewage water]. / Risikofaktoren der Belastung durch Shigatoxin-produzierende Escherichia coli (STEC) in Kläranlagen.

Shiga toxin producing Escherichia coli (STEC) in sewage influent into surface water are a potential source of human infections with STEC. Eight sewage treatment plants in Bavaria, Germany, were sampled at regular intervals from 2003 to 2004 in order to estimate STEC load and quantify risk factors. 95 of 378 samples (25 %) were tested positive for stx1and/or stx2 with PCR after enrichment culture. STEC elimination after treatment was 44 %. The following risk factors were analysed with logistic regression: location of sewage plant (rural vs. urban), treatment plant technology (two stage vs. three stage treatment) and sampling location (sewage input vs. sewage output). Rural plants had odds-ratios of 1,7 (95 % CI 1.03 - 2.69; p = 0.038) for a positive stx1 and/ or stx2 PCR result, sampling at sewage input of 2.1 (95 %CI 1.28 - 3.36; p = 0.003) and three stage plants of 1.51 (95 % CI 0.94 - 2.44; p = 0.087, not significant). Sampling after rain and after dry spells had no impact on STEC abundance (univariate Chi-square test = 0.01; df1; p = 0.920). Rural sewage plants had higher odds of STEC content. The influence of the sewage plant technology on the STEC load requires further clarification.

Health impacts of second-hand exposure to cat allergen Fel d 1 in infants.

BACKGROUND: Recent cross-sectional studies suggested that highest sensitization prevalences occur with moderate cat allergen exposures. We aimed to assess the impact of moderate levels of second-hand cat allergen exposure on the incidence of specific sensitization and wheezing in the framework of a birth cohort study. Therefore we restricted our analysis to infants without a cat at home since birth. METHODS: At infant's age 3 months, cat allergen levels were measured in the mattress dust of 1840 families without cats. At age 2 years, serum IgE specific to Fel d 1 was analyzed. Incidence of wheezing apart from respiratory infection was assessed by questionnaire. Logistic regression models were used to calculate adjusted odds ratios (OR) for the association between second-hand cat allergen exposure and health outcomes. RESULTS: Until age 2 years, 13 of 1301 infants (1%) were sensitized to cat allergen and 56 of 1492 infants (4%) had ever-wheezing without infection. Early exposure to second-hand cat allergen levels >or= 1 microg/g dust increased substantially the risk for specific sensitization to Fel d 1 (OR 10.9, 95% CI 3.4-35.0) and ever-wheeze without infection (OR 2.0, 95% CI 1.1-3.9) at age 2 years. CONCLUSIONS: Second-hand exposure to cat allergen in homes without cats is detrimental in terms of allergy development in infants.