Environmental impact of heavy pig production in a sample of Italian farms. A cradle to farm-gate analysis.

Four breeding piggeries and eight growing-fattening piggeries were analyzed to estimate potential environmental impacts of heavy pig production (>160kg of live height at slaughtering). Life Cycle Assessment methodology was adopted in the study, considering a system from breeding phase to growing fattening phase. Environmental impacts of breeding phase and growing-fattening phase were accounted separately and then combined to obtain the impacts of heavy pig production. The functional unit was 1kg of live weight gain. Impact categories investigated were global warming (GW), acidification (AC), eutrophication (EU), abiotic depletion (AD), and photochemical ozone formation (PO). The total environmental impact of 1kg of live weight gain was 3.3kg CO2eq, 4.9E-2kg SO2eq, 3.1E-2kg PO4(3-)eq, 3.7E-3kg Sbeq, 1.7E-3kg C2H4eq for GW, AC, EU, AD, and PO respectively. Feed production was the main hotspot in all impact categories. Greenhouse gases responsible for GW were mainly CH4, N2O, and CO2. Ammonia was the most important source of AC, sharing about 90%. Nitrate and NH3 were the main emissions responsible for EU, whereas P and NOx showed minor contributions. Crude oil and natural gas consumption was the main source of AD. A large spectrum of pollutants had a significant impact on PO: they comprised CH4 from manure fermentation, CO2 caused by fossil fuel combustion in agricultural operations and industrial processes, ethane and propene emitted during oil extraction and refining, and hexane used in soybean oil extraction. The farm characteristics that best explained the results were fundamentally connected with performance indicators Farms showed a wide variability of results, meaning that there was wide margin for improving the environmental performance of either breeding or growing-fattening farms. The effectiveness of some mitigation measures was evaluated and the results that could be obtained by their introduction have been presented.

Factors affecting life cycle assessment of milk produced on 6 Mediterranean buffalo farms.

This study quantifies the environmental impact of milk production of Italian Mediterranean buffaloes and points out the farm characteristics that mainly affect their environmental performance. Life cycle assessment was applied in a sample of 6 farms. The functional unit was 1 kg of normalized buffalo milk (LBN), with a reference milk fat and protein content of 8.3 and 4.73%, respectively. The system boundaries included the agricultural phase of the buffalo milk chain from cradle to farm gate. An economic criterion was adopted to allocate the impacts on milk production. Impact categories investigated were global warming (GW), abiotic depletion (AD), photochemical ozone formation (PO), acidification (AC), and eutrophication (EU). The contribution to the total results of the following farm activities were investigated: (1) on-farm energy consumption, (2) manure management, (3) manure application, (4) on-farm feed production (comprising production and application of chemical fertilizers and pesticides), (5) purchased feed production, (6) enteric fermentation, and (7) transport of purchased feeds, chemical fertilizers, and pesticides from producers to farms. Global warming associated with 1 kg of LBN resulted in 5.07 kg of CO2 Eq [coefficient of variation (CV)=21.9%], AD was 3.5 × 10(-3) kg of Sb Eq (CV=51.7%), PO was 6.8 × 10(-4) kg of C2H4 Eq (CV=28.8%), AC was 6.5 × 10(-2) kg of SO2 Eq (CV=30.3%), and EU was 3.3 × 10(-2) kg of PO4(3-) Eq (CV=36.5%). The contribution of enteric fermentation and manure application to GW is 37 and 20%, respectively; on-farm consumption, on-farm feed production, and purchased feed production are the main contributors to AD; about 70% of PO is due to enteric fermentation; manure management and manure application are responsible for 55 and 25% of AC and 25 and 55% of EU, respectively. Methane and N2O are responsible for 44 and 43% of GW, respectively. Crude oil consumption is responsible for about 72% of AD; contribution of CH4 to PO is 77%; NH3 is the main contributor to AC (92%); NO3(-) and NH3 are responsible for 55 and 41% of EU, respectively; contribution of P to EU is only 3.2%. The main characteristics explaining the significant variability of life cycle assessment are milk productivity and amount of purchased feed per kilogram of LBN. Improvement of LBN production per buffalo cow is the main strategy for reducing GW and PO; improvement of the efficiency of feed use is the strategy proposed for mitigating AD, PO, AC, and EU.

Emergence of Pseudomonas aeruginosa strains producing metallo-beta-lactamases of the IMP-15 and VIM-2 types in Mexico.

Eighty-six carbapenem non-susceptible Pseudomonas aeruginosa isolates collected in the National Institute of Respiratory Diseases of Mexico City were screened for the presence of metallo-beta-lactamase (MBL) activity using both E-test strips and a microbiological assay with EDTA-imipenem. Genomic comparisons and sequence analyses conducted with these isolates revealed the presence of bla(VIM-2) in two clonally related isolates, and bla(IMP-15) in a clonally unrelated isolate. Both genes were found to be carried by class 1 integrons, and bla(IMP-15) was additionally present on a broad host-range plasmid. This is the first report of co-existing P. aeruginosa strains producing different MBLs in a Mexican hospital, highlighting the necessity of appropriate surveillance to prevent dissemination of carbapenem resistance.

Impaired activation of Stat1 and c-Jun as a possible defect in macrophages of patients with active tuberculosis.

Studies of patients with active tuberculosis (TB) and infected healthy individuals have shown that interferon (IFN)-gamma is present in sites of Mycobacterium tuberculosis infection in comparable levels. This suggests that there is a deficiency in the macrophage response to IFN-gamma in TB patients. We used recombinant human IFN-gamma to stimulate adherent monocyte-derived macrophages from three groups of people: patients with active tuberculosis (TBP), their healthy household contacts (HHC) and healthy uninfected controls from the community (CC). We then evaluated the ability of the macrophages to inhibit the growth of M. tuberculosis H37Rv as well as their cytokine profile at early in infection (48 h). After IFN-gamma treatment, macrophages of healthy individuals (HHC and CC) controlled M. tuberculosis growth and produced mainly nitric oxide (NO) and interleukin (IL)-12p70, whereas TBP macrophages did not kill M. tuberculosis. Additionally, TBP macrophages produced low levels of NO and IL-12p70 and high levels of tumour necrosis factor (TNF)-alpha and IL-10. Transforming growth factor (TGF)-beta levels were similar among all three groups. M. tuberculosis infection had little effect on the cytokine response after IFN-gamma stimulus, but infection alone induced more IL-10 and TGF-beta in TBP macrophages. There were no differences in Stat1 nuclear translocation and DNA binding between the groups. However, the phosphorylated Stat1 and c-Jun (AP-1) in nuclear protein extracts was diminished in TBP macrophages compared to macrophages of healthy individuals. These results indicate an impairment of Stat1-dependent and Stat1-independent IFN-gamma signalling in macrophages of people with active tuberculosis, suggesting a different molecular regulation that could impact macrophage functionality and disease outcome.

Isolation and characterization of HC1: a novel human DNA repair gene.

Nucleotide excision repair (NER) acts on a broad spectrum of large lesions, while base excision repair removes individual modified bases. Although both processes have been well studied in human cells, novel genes involved in these DNA repair pathways have been described. Using a heterologous complementation approach, we identified a fetal human cDNA that complemented two Escherichia coli mutants that are defective in 3-methyl adenine glycosylase and in three endonucleases, all of which are enzymes with important roles in base excision repair. The central cDNA open reading frame complemented NER mutant strains and promoted an increase in survival rate of bacteria exposed to UV light. The corresponding protein was able to restore nucleotide-excision-repair activity when added to a cell extract from Chinese hamster ovary cells deficient in the ERCC1 protein, an enzyme known to promote incision at the 5' end of the lesion during NER. In contrast, that protein was not able to complement XPG Chinese hamster ovary cells deficient in the 3' incision step of NER. These data indicate a new human repair gene, which we named HC1; it is involved in the recognition of two kinds of DNA lesions and it contributes to the 5' DNA incision step in NER.

Serological cross-sectional survey of psoroptic sheep scab in Switzerland.

Sheep scab, caused by the mite Psoroptes ovis, is a notifiable disease in Switzerland. Mandatory prophylactic treatments are carried out in spring for all sheep grazing on common alpine pastures. Despite these strict control measures the number of outbreaks has been increasing in recent years, raising questions on the spread of this epizootic disease. To improve the traditional microscopic diagnosis, we developed an ELISA for the specific determination of antibodies against psoroptic antigens with sensitivity and specificity of 93.7 and 96.5%, respectively. Using this test, a serum bank, representative of the sheep population in Switzerland (approximately 15% of registered sheep flocks, randomly chosen, collected between February and May 1998), was screened. The prevalence using 16,404 sera was 10.4, and 11.9% of the 2083 flocks were diagnosed as positive. Additionally, there was a significant increase found for mean seropositivity relative to the flock size (P<0.001, linear regression). Therefore, larger flocks had a higher risk of sheep scab, which may be caused by more frequent animal movement. Spatial analysis of the results revealed a region with significantly higher risk (relative risk = 3.5, P<0.001) of seropositivity, where no cases have officially been notified in the period between 1997 and 1999. The next goal is to establish an efficient control strategy based on serological monitoring of the total sheep population.

[Effect of a single injection of doramectin on gastrointestinal nematode infections of sheep grazing on alpine pastures]. / Einfluss einer einmaligen Injektionsbehandlung mit Doramectin auf den Befall mit gastrointestinalen Nematoden bei gealpten Schafen.

The persistent effect of doramectin injectable against gastrointestinal nematodes was investigated in a controlled field study with 70 sheep kept on alpine pastures in Switzerland. After grazing on home pastures for four weeks 50 lambs and 20 ewes were allocated to two equal groups according to age and body weight. At turnout to alpine pasture in June doramectin (0.3 mg/kg) was administered by intramuscular injection to 25 lambs and 10 ewes (Group D), whereas control sheep (Group K) remained untreated. Animals of both groups were kept on separate pastures (altitude: 1100 m) and were rotated between three paddocks during a total grazing period of 13 weeks. After doramectin treatment faecal examinations of Group D sheep showed a marked reduction of the trichostrongyle egg output which remained close to zero for eight weeks. During this period serum pepsinogen levels did not indicate the presence of a substantial immature worm burden in the abomasal mucosa. In the last five weeks of the alpine grazing period the trichostrongyle egg counts increased markedly in the lambs of Group D. Lambs of the control group developed moderate-to-high Haemonchus-infections, and eight animals of this group had to be treated with anthelmintics. Lambs of Group D had gained significantly (P < 0.05) more weight eight weeks after turnout whereas the mean bodyweight stagnated during the last five weeks of the grazing period. The results indicate, that the single administration of 0.3 mg/kg doramectin to lambs and ewes provided good protection against severe infections with gastrointestinal nematodes for a period of approximately eight weeks.

Salmonella gastroenteritis outbreak among workers from a tertiary care hospital in Mexico City.

OBJECTIVE: To describe an outbreak of Salmonella gastroenteritis among employees of the National Institute of Nutrition (INNSZ) of Mexico City during July, 1994. METHODS: Employees who developed diarrhea or fever associated with gastrointestinal symptoms starting on July 14th were included for study as well as 50 healthy controls. A questionnaire was applied to all, and they also provided a stool sample, along with other 80 asymptomatic people (included the kitchen workers) in whom only stool culture was done. RESULTS: Ninety-seven employees that ate regularly at the Hospital's cafeteria were affected by the outbreak, and 67 of them (69%) could be evaluated. Most of them were nurses (34%), and handymen (27%). Most common symptoms were abdominal pain (97%), diarrhea (95%), nausea (91%), and fever (89%). Cultures from suspicious food items were all negative, but stool cultures from 10/70 cases were positive for Salmonella enteritidis vs. 0/133 in the controls. The ten S. enteritidis isolates resulted identical either by serotyping and by rapid amplified polymorphic DNA (RAPD) analysis. Cultures from all kitchen employees were negative for S. enteritidis. Breakfast meal on July 14th was associated with the development of gastroenteritis (61/67 cases vs 26/50 controls, p < 0.001), and particularly with an egg-covered meat plate (61/62 vs 13/26 controls, p < 0.0001). CONCLUSIONS: This outbreak was probably caused by eggs contaminated with Salmonella, since no one of the kitchen personnel was found to be an asymptomatic carrier, and the implicated recipe allows for inappropriate cooking. Recommendations to improve cooking procedures must be added to the usual regulations to diminish the frequency of foodborne disease outbreaks in hospitals.