Evidence of Bartonella sp. in questing adult and nymphal Ixodes ricinus ticks from France and co-infection with Borrelia burgdorferi sensu lato and Babesia sp

Ticks are known vectors for a wide range of pathogenic microorganisms. Their role in the transmission of some others is so far only suspected. Ticks can transmit multiple pathogens, however, little is known about the co-existence of these pathogens within questing ticks. We looked for the presence of DNA from three micro-organisms, Bartonella sp., Borrelia burgdorferi sensu lato and Babesia sp. which are known or suspected tick-borne pathogens, using a cohort of 92 questing Ixodes ricinus ticks collected from pastures in northern France. DNA was extracted from each individual tick and the presence of the three pathogens was investigated using Polymerase Chain Reaction (PCR) amplification. Nine among 92 samples (9.8%) demonstrated PCR products using Bartonella specific primers, 3 among 92 (3.3%) using Borrelia burgdorferi sensu lato specific primers and 19 among 92 (20.6%) using Babesia specific primers. Seven among 92 samples (7.6%) were PCR positive for at least two of the pathogens and one sample was positive for all three. Adult ticks (12/18; 67%) showed significantly higher infection rates compared to nymphs (11/74; 15%) for all three pathogens (P < 0.001). This study is the demonstration of the simultaneous presence of Bartonella sp., Borrelia burgdorferi sensu lato and Babesia sp. in questing Ixodes ricinus ticks.     

Use of a new and rapid milk progesterone assay to monitor reproductive activity in the cow

A new and rapid enzyme-amplified immunoassay (AELIA) has been developed for the measurement of progesterone in milk. The AELIA system is a non-isotopic method that gives results within 35 minutes. Milk progesterone concentrations measured in 10 cows sampled daily at various stages of the reproductive cycle were very similar to those recorded by a validated radioimmunoassay. The results show that the speed and sensitivity of the AELIA system would make it possible to diagnose pregnancy rapidly at about 24 days after insemination, to predict the onset of behavioural oestrus from decreasing progesterone values during the third week after a preceding oestrus, and to obtain a daily record of milk progesterone levels in animals treated for infertility of ovarian origin.     

Inheritance of coffee bean sucrose content in the interspecific cross Coffea pseudozanguebariae×Coffea liberica'dewevrei'

The sucrose content of coffee bean is an important component of the coffee flavour: the higher the sucrose content in green beans, the more intense coffee cup flavour: Beans of the anciently cultivated cultivar Coffea liberica‘dewevrei’ have low levels of sucrose compared with beans of the wild species Coffea pseudozanguebariae. In the present study, the inheritance of the sucrose accumulation in the interspecific cross C. pseudozanguebariae×C. liberica‘dewevrei’ was examined. The sucrose content was measured in mature beans of both parental species, and in F₁ and backcross hybrids using high‐pressure liquid chromatography coupled to pulsed amperometric detection. The sucrose accumulation in all but one hybrid, showed genetic additivity. A segregation distortion was identified in the offspring of the backcross to C pseudozanguebariae. There was no year effect and only a low genotype × year interaction. Consequences for breeding, in relation to the coffee cup taste improvement, are discussed.     

Thirty years of fleet dynamics modelling using discrete‐choice models: What have we learned?

Anticipating fisher behaviour is necessary for successful fisheries management. Of the different concepts that have been developed to understand individual fisher behaviour, random utility models (RUMs) have attracted considerable attention in the past three decades, and more particularly so since the 2000s. This study aimed at summarizing and analysing the information gathered from RUMs used during the last three decades around the globe. A methodology has been developed to standardize information across different studies and compare RUM results. The studies selected focused on fishing effort allocation. Six types of fisher behaviour drivers were considered: the presence of other vessels in the same fishing area, tradition, expected revenue, species targeting, costs, and risk‐taking. Analyses were performed using three separate linear modelling approaches to assess the extent to which these different drivers impacted fisher behaviour in three fleet types: fleets fishing for demersal species using active gears, fleets fishing for demersal species using passive gears and fleets fishing for pelagic species. Fishers are attracted by higher expected revenue, tradition, species targeting and presence of others, but avoid choices involving large costs. Results also suggest that fishers fishing for demersal species using active gears are generally more influenced by past seasonal (long‐term) patterns than by the most recent (short‐term) information. Finally, the comparison of expected revenue with other fisher behaviour drivers highlights that demersal fishing vessels are risk‐averse and that tradition and species targeting influence fisher decisions more than expected revenue.     

Coffee and liver diseases

Coffee consumption is worldwide spread with few side effects. Interestingly, coffee intake has been inversely related to the serum enzyme activities gamma-glutamyltransferase, and alanine aminotransferase in studies performed in various countries. In addition, epidemiological results, taken together, indicate that coffee consumption is inversely related with hepatic cirrhosis; however, they cannot demonstrate a causative role of coffee with prevention of liver injury. Animal models and cell culture studies indicate that kahweol, diterpenes and cafestol (some coffee compounds) can function as blocking agents by modulating multiple enzymes involved in carcinogenic detoxification; these molecules also alter the xenotoxic metabolism by inducing the enzymes glutathione-S-transferase and inhibiting N-acetyltransferase. Drinking coffee has been associated with reduced risk of hepatic injury and cirrhosis, a major pathogenic step in the process of hepatocarcinogenesis, thus, the benefit that produces coffee consumption on hepatic cancer may be attributed to its inverse relation with cirrhosis, although allowance for clinical history of cirrhosis did not completely account for the inverse association. Therefore, it seems to be a continuum of the beneficial effect of coffee consumption on liver enzymes, cirrhosis and hepatocellular carcinoma. At present, it seems reasonable to propose experiments with animal models of liver damage and to test the effect of coffee, and/or isolated compounds of this beverage, not only to evaluate the possible causative role of coffee but also its action mechanism. Clinical prospective double blind studies are also needed.     

Morphometric evaluation of changes in the digestive tract of rainbow trout (Oncorhynchus mykiss) due to fish meal replacement with soy protein concentrate

Effects of the complete replacement of fish meal (FM) by soy protein concentrate (SPC) in high-energy diets (23 MJ kg^− 1 gross energy) on intestinal and liver histology were investigated in rainbow trout (Oncorhynchus mykiss). We developed a novel morphometric method to quantify the changes at the macro- and micromorphology level. Fish were acclimatized to the diet for 90 d and were then fed 1.0 g kg BW^− 1 d^− 1 once per day for 14 d before 10 fish per diet were randomly sampled, 6 h after their last meal. Fold height, epithelium length, stroma proportion of the proximal and distal intestines were not affected by the diet. No significant diet effect was detected on the features of the valve in the distal intestine. Fold height was linked to epithelium length in the proximal and distal intestines and this relationship was not modified by FM replacement. Enterocyte height and width were lower in SPC-fed fish in the distal intestine, but in the proximal intestine their morphology was not affected by the diet. There was no diet effect on the number of cells infiltered between the enterocytes in the proximal and distal intestines. The enterocyte nucleus was closer to the apex in the proximal and distal intestines in SPC-fed fish, but the features of the nucleus were not affected by the diet. The mean hepatocyte volume was on an average 36% lower in SPC-fed fish and was positively correlated to the hepatosomatic index for fish fed this diet only. In conclusion, SPC used in the present study did not either cause inflammatory reaction of the gut nor affected the epithelium surface. We suggest that the modifications due to SPC are linked to variations in the metabolic status of the enterocyte.     

Flowering synchronisation between male and female West African cultivated yams (Dioscorea cayenensis-rotundata complex)

It has long been admitted that male and female cultivars of Dioscorea cayenensis-rotundata complex do not flower at the same period and consequently natural outcrossing rarely occurs. Flowering in thirteen (7 males and 6 females) traditional cultivars were studied. Four main results were obtained: i) the first bud emergence occurred 25 days earlier in males; ii) the male and female first flower opening overlapped for 10 days (85 to 95 days after sprouting); iii) for both sexes, highest frequency of flower opening occurred at mid-day; and iv) the female cultivar 1800 could flower for 8 consecutive days, with a peak between day 4 and day 8. These results are discussed in relation to intercrossing success. This revised version was published online in July 2006 with corrections to the Cover Date.     

Stereospecific analysis of phospholipid classes in skeletal muscle from rats fed different fat sources

The fatty acid (FA) and dimethylacetal profiles of the sn-1 and sn-2 positions of different phospholipid (PL) classes from skeletal muscle of rats as affected by dietary FA profiles were studied. Rats were fed either a control diet, an olive oil-enriched diet, or a sunflower oil-enriched diet. The FA composition of both positions of the studied PL classes was affected by diet to different extents. The FA composition of the sn-2 position of phosphatidylserine was the most influenced by diet, while phosphatidylinositol was less affected by dietary modification. The FA profile of phosphatidylcholine reflected consumed FA better than any other studied PL. Thus, olive oil rats showed higher oleic acid (C18:1 n-9) contents in both positions of phosphatidylcholine, and sunflower oil rats had higher proportions of arachidonic acid (C20:4 n-6) in the sn-1 position of this PL class. Dimethylacetals were scarcely affected by diet, and only the dimethylacetal composition of phosphatidylethanolamine showed significant modifications.     

Impact of direct drilling and conventional tillage on seasonal changes of soil water content in Chromic Haploxerert (south-west Spain)

A continuous monitoring of spatial and temporal variability of soil water content was studied under two soil management systems: direct drilling (DD) and conventional tillage (CT), during four consecutive seasons. The soil water content was read at different soil depths using multisensor capacitance probes in each soil-management treatment. During the first season (2003–2004), soil water content dynamics for both treatments were similar during the rainy season, although the DD plot was able to retain more water in the soil profile, and during the maximum evapotranspirative period faster soil water depletion took place in the CT plot. The 2004–2005 season registered a high evapotranspiration rate (1741 mm) with low rainfall (228 mm), promoting a low soil water recharge for both treatments. The 2005–2006 season registered an increase in rainfall, promoting a greater recovery of the soil water reserve in DD than CC plot. Finally, during the 2006–2007 season with an evapotranspiration rate ET₀ and rainfall of 1504 and 560 mm, respectively, DD retained more soil water content, mainly in the deeper zones, with progressive soil water depletion during the maximum evapotranspirative period in comparison to CT. Thus, DD was demonstrated to be a promising soil management technique for improving the soil water content.     

Explaining host–parasitoid interactions at the landscape scale: a new approach for calibration and sensitivity analysis of complex spatio-temporal models

Landscape Ecology - Linking spatial pattern and process is a difficult task in landscape ecology because spatial patterns of populations result from complex factors such as individual traits, the...