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Long-term migration of 137Cs in Swedish grassland soil profiles following the Chornobyl accident
Get PDFThis study presents long-term findings (1987-2008) on the vertical migration of 137Cs from the Chornobyl accident in undisturbed grassland soils in central and northern Sweden. We examined five mineral and three organic soils, with 137Cs deposition in 1986 ranging from 16 to 190 kBq m2. 137Cs activities were measured in 1 cm slices at depths of 0-10 cm and in 2.5 cm slices at 10-50 cm. Distribution (kBq m2) was calculated for different soil horizons, and migration rates were determined based on observed depths. During the initial period after the fallout (1987-1992), 137Cs was primarily located in the upper 0-2 cm layers of both mineral and organic soils, comprising 77 % to 94 % of the radionuclide. During the intermediate period (1994-2003), the average migration depth was 4.0 cm in mineral soils and 5.5 cm in the organic soils while during the later period (2004-2008) it was 4.4 and 7.0 cm, respectively. After about 20 years, approximately 80 % of the 137Cs activity was found in the upper 0-6 cm at five out of eight sites, and 75-78 % within 0-9 cm at two sites regardless of soil type. The average radionuclide migration rate of 137Cs in the period 1987 to 2008 across various sites was 0.31 cm yr-1. In mineral soils, the average migration rate was 0.28 cm yr-1 (range 0.13-0.47) and in organic soils it was 0.3 cm yr-1 (range 0.17-0.76). There was no significant relationship between soil clay content in mineral soils and the average migration depth of the radionuclide during the study period (P = 0.423)
Occurrence, risk factors and antimicrobial resistance of Campylobacter from poultry and humans in central Ethiopia: A one health approach
Get PDFBackground Campylobacter is a leading foodborne pathogen posing a significant One Health challenge due to broad animal reservoirs and serious antibiotic resistance. Despite frequent human-animal-environment interactions in Ethiopia, One Health studies on Campylobacter occurrence and transmission are crucial but lacking.Methodology/Principal Findings A cross-sectional study was conducted from March 2021 to March 2022 in central Ethiopia using a One Health approach to assess Campylobacter occurrence and resistance in humans, poultry and environment, and identify risk factors in humans and poultry. A total of 366 samples from 122 poultry farms were collected, including cloacal swabs, human stools, and poultry house floor samples. Epidemiological data on risk factors and respondents' awareness were gathered through interviews. Campylobacter spp. were isolated following ISO 10272, confirmed with multiplex PCR and tested for antimicrobial susceptibility using the disc diffusion method according EUCAST guidelines. Campylobacter spp. were detected in 12.5% samples, highest in poultry (19.6%), followed by humans (13.1%) and poultry house floor (4.9%). Campylobacter jejuni was the dominant species (80.4%), followed by C. coli (19.6%). In poultry, mixed farming with cattle increased Campylobacter colonization odds (adjusted odds ratio; AOR = 9.5), while all-in/all-out management decreased it (AOR = 8.4). In humans, Campylobacter infection was linked to raw milk consumption (AOR = 5.5), poultry access to living areas (AOR = 6.3), not using personal protective equipment when working with poultry (AOR = 8.3) and not washing hands after handling poultry and cleaning barn (AOR = 5.6). Farm workers had a knowledge gap in zoonotic risks, including Campylobacter and One Health. High antibiotic resistance was observed, especially to erythromycin (63.0%), ciprofloxacin (69.5%), tetracycline (89.1%), and oxytetracycline (73.9%), with 69.5% of isolates showing multidrug resistance.Conclusions/Significance The study revealed widespread occurrence of resistant Campylobacter spp. in poultry, workers, and the environment, highlighting the need for One Health interventions: improved biosecurity, hygiene, education, and responsible antimicrobial use to safeguard animal and human health
Coordination Chemistry of Solvated Metal Ions in Soft Donor Solvents
Get PDFThe structures of hexaammine solvated indium(III) and thallium(III) ions in liquid ammonia solution are determined by EXAFS. Both complexes have regular octahedral coordination geometry with mean In-N and Tl-N bond distances of 2.23(1) and 2.29(2) & Aring;, respectively. Ammine solvated thallium(III) in liquid ammonia is characterized with 205Tl NMR measurements. Solvents such as liquid ammonia, N,N-dimethylthioformamide (DMTF), trialkyl and triphenyl phosphite and phosphine are strong electron pair donors and thereby able to form bonds with a large covalent contribution with strong electron pair acceptors. A survey of reported structures of ammine, DMTF, trialkyl and triphenyl phosphite and phosphine solvated metal ions in the solid state and solution is presented. The M-N and M-S bond distances in ammine and DMTF solvated metal ions are compared with the M-O bond distance in the corresponding metal ion hydrates, expected to form mainly electrostatic interactions with metal ions. The d10 metal ions have high ability to form bonds with a high degree of covalency with increasing ability down the group and with decreasing charge of the metal ion. The difference in M-N and M-O bond distances between ammine solvated and hydrated metal ions with the same coordination geometry decreases significantly with the increasing ability of the metal ion to form bonds with a large covalent contribution. This difference correlates well with the covalent bonding index, gamma M2*r
Mapping pea seed composition through strategic selection of accessions from the Nordic gene bank
Get PDFThis study aims to utilise natural variation in pea seed composition from NordGen collections to identify key traits for optimized plant-based ingredients functionality while minimizing refined extraction processes. Given the impracticality of chemically analysing 1942 accessions, an algorithm-assisted approach was employed, using image-derived features and datasets to pre-select 51 accessions. Protein content, thousand kernel weight, perimeter, and G-value were determined as primary criteria via PCA, capturing variations in protein composition and other key components. Protein and starch content ranged from 21.2 to 36.9 % and 21.0-48.1 %, respectively. Image analysis linked geometry to composition, aiding pea selection and application. X-ray scattering differentiates peas based on starch structure. Proteomic profiling revealed that legumin and vicilin varied most, with legumin dominant in smooth peas and vicilin in wrinkled ones, enabling control of their ratio through selection. This study highlights the potential of using natural variation of seed composition for less-refined plant-based ingredients for various applications
Integrative taxonomic revision of endemic dwarf shrews from the Ethiopian Highlands
Get PDFThe biodiversity of the Ethiopian Highlands features a significant level of endemism. Among its diverse fauna, the genus Crocidura (Soricidae), with many cryptic species, remains poorly documented, particularly for species of minute size. This study describes a newly discovered minute shrew-one of the smallest mammals worldwide-and addresses the taxonomy of the so-called 'Afromontane clade' of Crocidura in Ethiopia. We combined extensive field sampling of recent and historical specimens with advanced genetic analyses (genome skimming, Illumina sequencing, and cytb phylogenetics) and morphological examination (external and craniodental) to delineate the new species and address taxonomic affinities among other minute Crocidura from Ethiopia. One of our newly collected forms represents a distinct genetic lineage, corresponding with unique physical characteristics such as tail length and cranial features. Its discovery highlights the rich, yet still incompletely understood, mammalian diversity in the Ethiopian Highlands and underscores the importance of integrating morphological and molecular data in taxonomic studies
Unnecessary suffering during the slaughter of cattle and pigs: mapping stun quality and associations to stun-to-stick intervals
Get PDFEnsuring that animals remain unconscious and insensible until death occurs via blood loss is critical for animal welfare at slaughter. Two key factors are the rapid sticking procedure following stunning and a correct assessment of stunning efficiency. This observational study aimed to map and assess variations in stun quality among carbon dioxide (CO2) stunned pigs and mechanically stunned cattle slaughtered under commercial conditions in Sweden. It also examined whether the duration of the stun-to-stick interval was associated with signs of consciousness. Data were collected between May 2023 and November 2024 across five pig slaughterhouses (n = 2,795 pigs) and six cattle slaughterhouses (n = 330 cattle). Stun quality was assessed based on established protocols and categorised as either good, doubt, shallow or poor. The primary findings revealed that longer stun-to-stick intervals were significantly associated with inadequate stun quality (i.e. shallow or poor stunning) and significantly increased the likelihood of re-stunning. In total, 96.1% of the pigs were adequately stunned. Notably, the proportion of pigs with inadequate stun quality ranged from 1.2 to 16.6% across slaughterhouses, with poor stunning observed in 0 to 9.1%. Re-stunning rates varied from 1.6 to 6.4%, and stun-to-stick intervals ranged from 32 to 199 s. For cattle, 92.7% of the animals were adequately stunned, with inadequate stunning ranging from 0 to 18.5%, poor stunning from 0 to 14.8%, re-stunning rates from 0 to 14.0%, and intervals between 77 and 192 s. The results indicated that intervals of less than 59 s for pigs and 99 s for cattle were associated with the lowest rates of inadequate stunning. Furthermore, the observed variation in stun quality among slaughterhouses highlights the potential for improvement in stunning practices, particularly in slaughterhouses with higher rates of stunning failures. Not all animals displaying symptoms of inadequate stunning were identified by the slaughterhouse personnel; instead, they continued along the line, potentially conscious, which suggests critical gaps in monitoring. The correct use of stunning equipment, along with continuous training of personnel to accurately recognise signs of recovery, is crucial for protecting animals from unnecessary suffering throughout the slaughter process
Phenotypic mechanisms of varroa resistant honey bees
Get PDFThe parasitic mite Varroa destructor poses a major threat to global honey bee (Apis mellifera) populations, undermining colony health through parasitism and virus transmission. While most managed colonies rely on chemical treatments, several naturally surviving populations in Europe have persisted for decades without interventions, offering insights into host–parasite interactions and resistance mechanisms. This thesis investigates three such populations from Sweden, France, and Norway, focusing on suppressed mite reproduction (SMR) and chemical communication. In Swedish and French populations, reduced mite reproductive success was primarily driven by brood traits rather than adult worker behaviour. Caging experiments confirmed that adult interaction was unnecessary to elicit SMR, underscoring intrinsic brood characteristics. In the Gotland population, resistant larvae exhibited distinct cuticular chemical profiles, notably reduced brood ester pheromones (BEP) at times critical for mite oogenesis. Additionally, the ratio of fatty acid ethyl esters (FAEE) to fatty acid methyl esters (FAME) increased when brood was infested, demonstrating phenotypic plasticity in pheromone expression. Even when treated for varroa, Gotland colonies maintained low mite reproduction, indicating SMR is partly constitutive. These findings suggest both fixed and plastic resistance traits coexist, offering adaptive flexibility under parasite pressure. This work advances understanding of host–parasite coevolution and highlights brood pheromone modulation as a potential, heritable mechanism of resistance, informing future breeding strategies for mite-resistant bees
Effects of delayed regeneration and slash removal 30 years after establishment of Norway spruce
Get PDFTreatments done in the regeneration phase significantly affect seedling growth and survival. Postponing regeneration up to four years after clearfelling can reduce seedling damage and mortality caused by pine weevils (Hylobius abietis). However, under delayed establishment, competing vegetation can colonize the site, possibly reducing seedling growth. Slash removal after clearfelling can facilitate later regeneration treatments such as site preparation and planting, increasing planted seedlings' survival. But slash removal can also reduce long-term stand growth, due to nutrient removal from the site. In this study, the long-term effects of clearcut age and slash removal on volume production was evaluated 30-years after planting Norway spruce. Data was collected from a long-term experiment established between 1989 and 1993. The experiment included four sites in southern Sweden. At each site, a clearcut was made every year from 1989 to 1993. To study the slash-removal effect, slash was retained on half of the clearcut area and removed from the other half. To study the effect of clearcut age, clearcuts were planted each subsequent year until the end of the experiment, creating five different clearcut ages. Clearcut ages were compared when they had reached the same age. For the 1500 largest trees per hectare, the total volume significantly differed among clearcut ages. The youngest clearcut age had higher total volume than the oldest. There was also a significant difference between slash treatments, where slash removal lowered total volume compared to slash retention. However, delaying regeneration treatments caused a larger total volume loss than slash removal
Variations in cow behaviour after regrouping in a conventional Swedish dairy herd
Get PDFA common management practice of commercial dairy farms is grouping cows according to their nutritional needs. Having different lactation groups also implies the regrouping of animals during their lactation period. Real-time locating systems based on ultra-wideband devices provide information about the cow's position inside barns. This information can be used to infer time budgets and animal locations on a continuous basis. The present study aimed to evaluate the behavioural changes that could be induced in dairy cows when regrouping between lactation groups by using location data obtained from real-time locating systems technology. This study is based on observational data from a commercial dairy farm, where 12 regrouping events, each involving between 3 and 15 cows, were recorded without any experimental intervention. The analyses included six months of data from two lactation groups with around 100 cows in each group. The effects of regrouping on time budgets and home range were analysed by comparing changes in regrouped cows before and after the process, and by comparing regrouped cows with their matched controls. The results showed that regrouping had a slight impact on the feeding and resting times of dairy cows. In contrast, parity was associated with opposing effects on feeding and resting times. Furthermore, regrouped cows tended to cover a larger area of the barn. The extent to which regrouped cows increased their use of barn space was also affected by the number of cows regrouped simultaneously. Our analysis of location data from a commercial dairy herd provides new insights into the impact of regrouping events on cow behaviour and welfare in commercial settings