A serosurvey for spotted fever group Rickettsia and Coxiella burnetii antibodies in rural dogs and foxes, Chile.

Antibodies against Spotted Fever Group (SFG) Rickettsia and Coxiella burnetii, investigated through indirect antibody immunofluorescence tests, were detected in serum samples from 3.1% and 0% of 358 rural dogs, respectively, and in none of 32 wild foxes tested. SFG Rickettsia seropositive dogs were only detected in the Mountain Desert (8%) and the Steppe-Mediterranean (9%) regions. Exposure in the Mountain Desert, where no ticks and fleas were found on any dog, could correspond to a new SFG Rickettsia sp. recently described in soft ticks or to a related agent. Our survey confirms low endemicity in the country of C. burnetii, as observed in recent serosurveys in humans.

Effects of restricted vs. step up dietary adaptation for 6 or 9 days on feedlot performance, feeding behaviour, ruminal and blood variables of Nellore cattle.

This study was designed to determine effects of quantitatively restricted intake of the final finishing diet as a means of dietary adaptation compared with diets increasing in concentrate (step up) over periods of 6 and 9 days on feedlot performance, carcass characteristics, feeding behaviour, blood gas profile and rumen morphometrics of Nellore cattle. One hundred twenty 22-month-old Nellore bulls (352 ± 20 kg) were randomly allocated in 24 pens and fed for 84 days. The experimental design was a completely randomized block with 2 × 2 factorial arrangement of treatments: adaptation using either step up protocol for 6 days or 9 days or restriction protocol for 6 days or 9 days, where the pen (five bullocks/pen; six pens/treatment) was considered the experimental unit. Cattle adapted by step up protocol had significantly greater average daily gain throughout the study when compared to those adapted by restriction protocol, regardless of adaptation length. During the adaptation period, a greater dry matter intake fluctuation was observed for animals maintained on restriction programme when compared to those adapted to the finishing diets using step up protocol. In addition, a protocol × length interaction for rumenitis scores was observed, where the level of injuries to the ruminal wall was significantly higher for the cattle adapted by restriction protocol for 9 days and lower for animals submitted for 9 days to the step up programme. Likewise, a protocol × length interaction for mitotic index was observed, in which cattle adapted by step up protocol for 9 days had lower numbers of cells in mitosis. Thus, the step up protocol led to better feedlot performance, and based on this fact, the length of 9 days promoted better rumen epithelium adaptation of Nellore cattle to high-concentrate diets.

Spirocerca lupi isolated from gastric lesions in foxes (Vulpes vulpes) in Sicily (Italy).

Spirocerca lupi (Rudolphi 1809) is a cosmopolitan nematode of dogs and wild carnivores. In the past it has been reported in Italy, mainly in southern regions and in Sicily, where the parasite was observed in foxes in 2005. The parasite typically produces nodular masses in the oesophagus and thoracic aorta. During the 2003-2004 hunting season, the authors investigated a total of 55 foxes (Vulpes vulpes) hunted or killed by car accidents in the provinces of Palermo and Agrigento. All the foxes were subjected to necropsy and 6 (9.16%) had S. lupi nodules located exclusively in the gastric wall. The nature of the nodules was determined by opening them and detecting the nematodes inside, which were identified as S. lupi. Some of the nodules were characterized anatomopathologically and histopathologically. The formation of the parasitic nodule in the stomach only suggests a deviation from the route commonly followed by the nematode to reach the oesophagus, the elective anatomical site for completion of its lifecycle. This survey gives a contribution to the epidemiology of this parasite which is severely outdated in Italy and highlights some distinctive features of the life cycle and parasite migration.

Genetic diversity of Anaplasma marginale strains from cattle farms in the province of Palermo, Sicily.

Bovine anaplasmosis, caused by the tick-borne rickettsia Anaplasma marginale, is endemic in Sicily and results in economic loss to the cattle industry. This study was designed to characterize strains of A. marginale at the molecular level from cattle in the Province of Palermo, Sicily. Seropositivity of cattle >or=1 year old for A. marginale in the study area ranged from 62% to 100%. The observed prevalence of A. marginale infections in cattle herds ranged from 25% to 100%. Two predominant A. marginale msp4 genotypes were found. A positive correlation was found between the prevalence of infection and the presence of Rhipicephalus (Boophilus) annulatus. Phylogenetic analysis of msp4 sequences of European strains of A. marginale did not provide phylogeographical information. These results suggest that development of farm husbandry systems and vaccines for genetically heterogeneous populations of A. marginale are needed for control of anaplasmosis in this region of Sicily.

Virulence regulators RfaH and YaeQ do not operate in the same pathway.

The expression of virulence factors such as hemolysin and lipopolysaccharides in Proteobacteria is regulated by the transcription elongation factor RfaH. RfaH reduces pausing and termination at intergenic sites, and thus allows RNA polymerase to conclude transcription of the distal genes in long virulence operons. The yaeQ gene of Salmonella enterica sv. Typhimurium has been identified as a high-copy-number suppressor of the hemolytic defect in an rfaH deletion strain, leading to speculation regarding a direct role of YaeQ in the transcriptional control of bacterial virulence. In order to evaluate this hypothesis, yaeQ genes from Escherichia coli and S. enterica sv. Typhimurium were cloned and expressed. Their products, purified YaeQ proteins, displayed no antitermination effects in in-vitro transcription assays over a wide range of concentrations, neither by themselves nor in competition with RfaH. When overexpressed in vivo, plasmid-borne E. coli and S. enterica sv. Typhimurium yaeQ genes also failed to restore hemolytic activity in an rfaH deletion strain under conditions in which episomal E. coli rfaH and its orthologs exhibited full complementation of the genomic rfaH deletion. Taken together, our findings do not support the hypothesis of YaeQ involvement in RfaH-dependent regulation of virulence, even in stoichiometric excess in vitro or upon overexpression in vivo.

Assessment of risk factors for pancreatic resection for cancer.

A series of 101 consecutive patients undergoing pancreatic resection for cancer was retrospectively analyzed to define factors that may affect the immediate postoperative outcome. Overall morbidity and mortality were 28.7% and 10.9%, respectively, although these figures were greatly reduced during the last years; the complication rate dropped from 55.6% (1981-1987) to 20.0% (1993-1995) and the mortality from 16.7% to 6.7%. At univariate statistical analysis the patient characteristics (sex, age, American Society of Anesthesiologists [ASA] class, nutritional status, jaundice), tumor characteristics (site, size, TNM stage, and grading), and type of surgery were found not to affect postoperative morbidity and mortality. In contrast, a significantly lower rate of complications was observed in patients not undergoing gastric resection, in those who received 3 units or less of blood intraoperatively, and in subjects operated more recently (after 1990). At multivariate analysis the period when the operation was performed was the only independent variable that affected the immediate postoperative outcome. Among the examined factors, only the experience acquired over time regarding the intra- and perioperative treatment of these patients seems able to lower the rate of postoperative complications.