Echinococcus multilocularis (Cestoda,Taeniidae) in Red foxes (Vulpes vulpes) in northern Belgium

The first record of the tapeworm Echinococcus multilocularis (Cestoda, Taeniidae) in Red foxes (Vulpes vulpes) in northern Belgium is described. Between 1996 and 1999, 237 dead foxes were examined for the presence of this tapeworm using the intestinal scraping technique. Four foxes (1.7%) were found to be infected with E. multilocularis and showed medium to very high parasitic burdens. Three infected foxes originated from the south of the study area and the fourth animal came from the north of the study area near the border with The Netherlands. These findings are discussed in relation to the high endemicity of E. multilocularis in southern Belgium and to the increased distribution of the Red fox (V. vulpes) in northern Belgium during the last two decades.     

Minimum space allowance for transportation of swine by road

Space allowance for animals in transit is a consistent concern in many countries that are developing codes of practice and regulations to assure humane treatment of food producing animals. The minimum space allowance requirements for a broad size range of swine in transit has not been well described or scientifically substantiated. A maximal loading pressure recommendation for pigs weighing from 5 to 250 kg was derived by a consultative process involving the swine transportation industry, animal welfare groups, and a literature review. The recommended maximal loading pressure under ideal conditions for swine loaded in groups can be described as a hoerl model y = (37.53)(0.9969)w(W0.5008), where y = loading pressure in kg body weight/m2 and W = average animal body weight in kilograms.     

Immunisation against Theileria parva in eastern Zambia: influence of maternal antibodies and demonstration of the carrier status

Immunisation of calves by the infection and treatment method (I & T) has been extensively used in the eastern province of Zambia to control East Coast fever (ECF), a protozoan tick-borne disease. This paper presents the results of a field longitudinal study, which included a total of 148 Angoni calves. After immunisation against ECF, they were monitored for a full rainy season, coinciding with the main peak of activity of the vector of Theileria parva, the tick Rhipicephalus appendiculatus. Dysimmunisation (acute reaction generated by I & T immunisation), seroconversion and mortality are among the parameters recorded. The effect of maternal antibodies on these parameters was analysed and also studied in experimental conditions on two calves. Before immunisation, young calves had a higher seroprevalence than older animals (maternal antibodies) but their post-immunisation seroprevalence was lower. There was no evidence that their immunoprotection was weaker but this indicates that the post-immunisation seroconversion is probably not a reliable tool to monitor the efficacy of calf immunisation. The carrier state of cattle after immunisation was investigated in experimental conditions on three bovines whereas in the field, the infection prevalence in the ticks was estimated using the relation between the tick burden and the T. parva contacts with the calves. The ability of larval and nymphal R. appendiculatus ticks to pick-up T. parva from carriers and to transmit it to na?ve animals after moulting was assessed. It was found that both instars are able to transmit clinical and lethal ECF but that the prevalence of T. parva infection in nymphs is much lower than in adults, confirming the primary role of adults in the transmission of ECF in endemic conditions. Similar results were obtained from the field whereby the ECF peak corresponds with the peak of adult R. appendiculatus activity. The infection prevalence in the ticks was however much lower in the field than in experimental conditions indicating that an important proportion of them feed on alternative hosts. Old ticks seemed to have lost part of their infectivity.     

Transmission of Theileriosis in the Traditional Farming Sector in the Southern Province of Zambia during 1995–1996

The incidence of first contact with the protozoan Theileria parva was determined in three traditional cattle herds in the Southern Province of Zambia in 1995 and 1996. The majority of first contacts occurred during the dry season in June, July and August, at a time of nymphal activity and in the absence of Rhipicephalus appendiculatus adults, indicating that larva to nymph transmission plays a more prominent role than nymph to adult transmission under the prevailing conditions.     

Land Use – Land Cover Conversion, Regeneration and Degradation in the High Elevation Bolivian Andes

Regional land-cover change affects biodiversity, hydrology, and biogeochemical cycles at local, watershed, and landscape scales. Developing countries are experiencing rapid land cover change, but assessment is often restricted by limited financial resources, accessibility, and historical data. The assessment of regional land cover patterns is often the first step in developing conservation and management plans. This study used remotely sensed land cover and topographic data (Landsat and Shuttle Radar Topography Mission), supervised classification techniques, and spectral mixture analysis to characterize current landscape patterns and quantify land cover change from 1985 to 2003 in the Altiplano (2535–4671 m) and Intermediate Valley (Mountain) (1491–4623 m) physiographic zones in the Southeastern Bolivian Andes. Current land cover was mapped into six classes with an overall accuracy of 88% using traditional classification techniques and limited field data. The land cover change analysis showed that extensive deforestation, desertification, and agricultural expansion at a regional scale occurred in the last 20 years (17.3% of the Mountain Zone and 7.2% of the Altiplano). Spectral mixture analysis (SMA) indicated that communal rangeland degradation has also occurred, with increases in soil and non-photosynthetic vegetation fractions in most cover classes. SMA also identified local areas with intensive management activities that are changing differently from the overall region (e.g., localized areas of increased green vegetation). This indicates that actions of local communities, governments, and environmental managers can moderate the potentially severe future changes implied by the results of this study.     

Über das Vorkommen der Zwiebelblattlaus,Myzus ascalonicus DONC., im Alpenraum

Ohne Zusammenfassung     

Effects of Addition of Tissue‐Type Plasminogen Activator in In Vitro Fertilization Medium on Bovine Embryo Development and Quality

Plasminogen activators/Plasmin system plays pivotal role in regulating reproductive functions of mammals. Here, we examined the effects of modification of in vitro fertilization medium (IVF medium) with the addition of tissue‐type plasminogen activator (t‐PA), on bovine embryo development and quality, assessed by quantification of expression of various genes related to metabolism, oxidation, implantation and apoptosis. In addition, plasminogen activator activity (PAA) and plasminogen activator inhibition (PAI) were measured in the spent media. After conventional IVM, 2016 cumulus‐oocyte complexes (COCs) were divided into four groups with modified composition of the IVF medium containing t‐PA and/or its inhibitor epsilon‐aminocaproic acid (control, t‐PA, t‐PA+ε‐ACA, ε‐ACA). Presumptive zygotes were cultured for 8 days in synthetic oviductal fluid (SOF) medium; gene expression studies were carried out on morulae and blastocysts. t‐PA alone significantly suppressed cleavage and blastocyst formation rates, but this effect was neutralized by the addition of ε‐ACA. PAA in the treated group was significantly reduced by ε‐ACA, but without total elimination. Significant differences were detected in the expression of genes related to apoptosis and/or cell cycle arrest (BAX, BCL2L1, KAT2B) between embryos produced in t‐PA‐modified media and controls, giving an overall notion that the inferior developmental competence of treated embryos may be attributed to apoptotic phenomena induced by t‐PA. In conclusion, it appears that excessive t‐PA content in the IVF media, suppresses blastocyst formation rate, possibly due to induction of apoptotic phenomena.     

Turnover of Se in adequately fed chickens using Se‐75 as a tracer

Inorganic selenium (Se) in the form of selenite is applied to livestock to avoid Se deficiency. Selenite is, however, an artificial Se source in diets of unsupplemented chickens. It is therefore hypothesized that organic Se sources, such as Se‐enriched yeast and wheat, could be a more suitable Se supply in animal nutrition, although information on the transition of Se from organic Se sources in fast‐growing chickens is scarce. In this work, chickens were fed a low Se diet (0.27 ± 0.01 mg Se/kg, Se‐enriched yeast) until 20 days of age, after which the Se concentration was increased to maximum concentration allowed by the poultry industry in Europe (0.5 p.p.m. Se). At the same time, a daily contribution of carrier‐free ⁷⁵Se tracer from labelled wheat was administered from day 20 to 27. The chickens showed S and Se homeostasis, as the concentration of S and Se in liver, blood or kidney remained about constant, and steady state of S and Se in the other organs was reached 1 day after the diet shift. The uptake of ⁷⁵Se was readily seen in all organs. After 1 week, the depuration of the ⁷⁵Se tracer was followed, and biological half‐lives and retention in individual organs were determined. The shortest biological half‐lives were observed in major metabolic organs, the liver, kidney and pancreas with half‐lives close to 4 days. There was a significant (p < 0.05) uptake in lung, brain and muscle that reached steady state when the administration of ⁷⁵Se was terminated. The half‐life of ⁷⁵Se in heart was 9 days and 7 days in blood. The longest half‐lives were observed in muscle (12 days), brain and lungs (13 days). All half‐lives were shorter than in Se deplete animals.     

Teton Russet: An Early-Maturing,Dual-Purpose Potato Cultivar Having Higher Protein and Vitamin C Content,Low Asparagine,and Resistances to Common Scab and Fusarium Dry Rot

Teton Russet is an early-maturing, medium-russeted, potato cultivar with high merit for both fresh-pack and processing. In early harvest trials in the Pacific Northwest, Teton Russet had total yields similar to Russet Norkotah, and higher than Ranger Russet and Russet Burbank. Marketable yield of Teton Russet in the early harvest trials was also comparable to or higher than Russet Norkotah in Washington and Oregon, and higher than Ranger Russet and Russet Burbank at these sites, as well as in Idaho. In full-season trials, while total yield of the earlier-maturing Teton Russet tended to be lower than Ranger Russet and Russet Burbank, marketable yield was generally higher than Russet Burbank across the majority of sites due to its higher percentage of U.S. No. 1 tubers. Teton Russet is suitable for processing, with acceptable fry color following up to 8 months of storage at 8.9 °C. Uniformity of fry color was also very consistent. Teton Russet has shown lower levels of the amino acid asparagine relative to Ranger Russet and Russet Burbank which may contribute to lower acrylamide levels in French fries and other processed potato products. Teton Russet is notable for having resistance to common scab (Streptomyces spp.) and Fusarium dry rot, and is moderately resistant to tuber net necrosis. Analyses have also shown Teton Russet to have significantly higher protein levels than Russet Norkotah, Ranger Russet, and Russet Burbank, as well as higher vitamin C content than Russet Norkotah and Russet Burbank. Teton Russet was released in 2011 by the USDA-ARS and the Agricultural Experiment Stations of Idaho, Oregon, and Washington, and is a product of the Pacific Northwest Potato Variety (Tri-State) Development Program.     

Multi-model comparison on the effects of climate change on tree species in the eastern U.S.: results from an enhanced niche model and process-based ecosystem and landscape models

Context

Species distribution models (SDM) establish statistical relationships between the current distribution of species and key attributes whereas process-based models simulate ecosystem and tree species dynamics based on representations of physical and biological processes. TreeAtlas, which uses DISTRIB SDM, and Linkages and LANDIS PRO, process-based ecosystem and landscape models, respectively, were used concurrently on four regional climate change assessments in the eastern Unites States.

Objectives

We compared predictions for 30 species from TreeAtlas, Linkages, and LANDIS PRO, using two climate change scenarios on four regions, to derive a more robust assessment of species change in response to climate change.

Methods

We calculated the ratio of future importance or biomass to current for each species, then compared agreement among models by species, region, and climate scenario using change classes, an ordinal agreement score, spearman rank correlations, and model averaged change ratios.

Results

Comparisons indicated high agreement for many species, especially northern species modeled to lose habitat. TreeAtlas and Linkages agreed the most but each also agreed with many species outputs from LANDIS PRO, particularly when succession within LANDIS PRO was simulated to 2300. A geographic analysis showed that a simple difference (in latitude degrees) of the weighted mean center of a species distribution versus the geographic center of the region of interest provides an initial estimate for the species’ potential to gain, lose, or remain stable under climate change.

Conclusions

This analysis of multiple models provides a useful approach to compare among disparate models and a more consistent interpretation of the future for use in vulnerability assessments and adaptation planning.