123 research outputs found
Effects of mineral amendments on trace elements leaching from pre-treated marine sediment after simulated rainfall events
Bauxite extraction by-products (red mud) were used to evaluate their potential ability to stabilize trace elements from dredged and aerated/humidified marine sediment. The investigated by-products were: bauxaline®(BX) that is a press-filtered red mud; bauxsol™(BS) that is a press-filtered red mud previously washed with excess of seawater, and gypsum neutralized bauxaline® (GBX). These materials were separately mixed to dredged composted sediment sample considering 5% and 20% sediment: stabilizer ratios. For pilot experiments, rainfall events were regularly simulated for 3 months. Concentrations of As, Mo, Cd, Cr, Zn, Cu, and Ni were analyzed in collected leachates as well as toxicity. Results showed that Cd, Mo, Zn, and Cu were efficiently stabilized in the solid matrix when 20% of BX, BS, and GBX was applied. Consequently, toxicity of leachates was lower than for the untreated sediment, meaning that contaminants mobility was reduced. A 5% GBX was also efficient for Mo, Zn and Cu stabilization. In all scenarios, As stabilization was not improved. Compared to all other monitored elements, Mo mobility seemed to depend upon temperature-humidity conditions during pilot experiments suggesting the need of further investigations
The role of pasteurella spp and of Mycoplasma bovis in respiratory diseases in young cattle
Lors des essais terrains d’un traitement antibiotique chez des veaux d’éle vage atteints de maladies respiratoires, la flore trachéobronchique a été inven toriée à différentes périodes : à l’arrivée, avant traitement et après guérison. Le rôle de l’association synergique Mycoplasma bovis - Pasteurella haemoly- tica Al apparaît clairement. Les conditions d’élevage et la participation de certains virus (RSV) sont encore des éléments importants de la pathogénèse et du pronostic des bronchopneumonies infectieuses enzootiques.When we tried an antibiotic treatment on clinical trials on weaner calves with respiratory diseases, tracheobronchial flora was examined at different moments : on the day of the arrival, before treatment and after recovery. The role of the synergistic association of Mycoplasma bovis / Pasteurella haemo- lytica A1 in the development of troubles appears to be confirmed. Bad breeding conditions and the participation of a virus (RSV) are important components of pathogenesis and prognosis of bovine Endemic Infectious Broncho pneumonia
Removal processes for tributyltin during municipal wastewater treatment
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2013 Springer.The fate and behaviour of tributyltin (TBT) at two wastewater treatment works was examined. Both sites had two inlet streams, and each utilised high rate biological filters (biofilters) on one the streams, before treatment of the combined flows on trickling filters, with one having additional tertiary processes, installed to remove ammonia and solids. The study was designed to determine if these processes enhanced the removal of TBT. Degradation of TBT was observed in one of the biofilters, possibly as a result of temperature and hydraulic loading. At the treatment works with tertiary processes, the mass flux showed the overall removal of TBT was 68 %, predominantly due to removal with solids in the primary settlement processes. However, overall removal of 95 % was observed in the conventional trickling filter works with 94 % of this due to biodegradation in the trickling filter. The two works both removed TBT, but at different treatment stages and by different processes. Differences in the form (solubility) of TBT in the influent may have attributed to this, although further understanding of factors controlling degradation would allow for a more complete assessment of the potential of biological processes to remove hazardous compounds from wastewaters.United Utilities PL
First Expert Elicitation of Knowledge on Drivers of Emergence of Bovine Besnoitiosis in Europe
Bovine besnoitiosis (BB) is a chronic and debilitating parasitic disease in cattle caused by the protozoan parasite Besnoitia besnoiti. South European countries are affected and have reported clinical cases of BB. However, BB is considered as emerging in other countries/regions of central, eastern and northern Europe. Yet, data on drivers of emergence of BB in Europe are scarce. In this study, fifty possible drivers of emergence of BB in cattle were identified. A scoring system was developed per driver. Then, the scoring was elicited from eleven recognized European experts to: (i) allocate a score to each driver, (ii) weight the score of drivers within each domain and (iii) weight the different domains among themselves. An overall weighted score was calculated per driver, and drivers were ranked in decreasing order of importance. Regression tree analysis was used to group drivers with comparable likelihoods to play a role in the emergence of BB in cattle in Europe. Finally, robustness testing of expert elicitation was performed for the seven drivers having the highest probability to play a key role in the emergence of BB: i.e., (i) legal/illegal movements of live animals from neighbouring/European Union member states or (ii) from third countries, (iii) risk of showing no clinical sign and silent spread during infection and post infection, (iv) as a consequence, difficulty to detect the emergence, (v) existence of vectors and their potential spread, (vi) European geographical proximity of the pathogen/disease to the country, and (vii) animal density of farms. Provided the limited scientific knowledge on the topic, expert elicitation of knowledge, multi-criteria decision analysis, cluster and sensitivity analyses are very important to prioritize future studies, e.g., the need for quantitative import risk assessment and estimation of the burden of BB to evidence and influence policymaking towards changing (or not) its status as a reportable disease, with prevention and control activities targeting, firstly, the top seven drivers. The present methodology could be applied to other emerging animal diseases
First description of pestivirus disease in Rupicapra pyrenaica pyrenaica
Understanding the circulation of pestiviruses in wild ungulates is potentially important to explain variations
in the number of animals in these species, and to implement pestivirus control programs in
domestic animals. In 2002 in the French Pyrenees, symptoms of amyotrophy and weight loss, associated
with bilateral alopecia with hairless and highly pigmented areas on the nose, around the eyes and
the ear margins were found in 8 Pyrenean chamois (Rupicapra pyrenaica pyrenaica) between 1 and 9
years old, 6 of which had been captured alive and 2 were found dead. These lesions were uncharacteristic.
The intensity of abomasal or lung parasitism varied from one animal to the other. Pestiviruses
were isolated in all 6 animals captured alive, but no anti-NS2/3 antibodies were found. Many questions
remain on the transitory or persistent nature of the infection, and on the conditions of viral transmission
within the Rupicapra genus.Comprendre la circulation de
pestivirus chez les ongulés sauvages est potentiellement important pour expliquer les
variations d'effectifs dans ces espèces et pour réaliser les programmes de contrôle des
pestiviroses atteignant les animaux domestiques. En 2002 dans les Pyrénées ariégeoises, des
symptômes d'amyotrophie et d'amaigrissement, associés à des signes d'alopécie bilatérale,
avec des zones cutanées glabres et fortement pigmentées sur le chanfrein, le pourtour des
yeux et les marges auriculaires ont été observés sur 8 isards (Rupicapra pyrenaica
pyrenaica) âgés de 1 à 9 ans, dont 6 avaient été capturés vivants et 2 trouvés morts. Les
lésions étaient peu caractéristiques. L'intensité du parasitisme abomasal ou pulmonaire
variait d'un individu à l'autre. Un pestivirus a été mis en évidence sur les 6 animaux
capturés vivants et un des deux récupérés morts (7 cas sur 8), mais aucun anticorps dirigé
contre la protéine NS2/3 n'a été trouvé. De nombreuses questions persistent sur la nature
transitoire ou persistante de l'infection et sur les modalités de transmission au sein du
genre Rupicapra
Effects of kefir on coccidial oocysts excretion and performance of dairy goat kids following weaning
The aim of this study was to investigate effects of kefir, a traditional source of probiotic, on coccidial oocysts excretion and on the performance of dairy goat kids following weaning. Twin kids were randomly allocated to one of two groups at weaning. Kids of the first group received 20 ml of kefir daily for 6 weeks (KEF), while kids in the control group were given a placebo (CON). Individual faecal samples were regularly (n = 18 per kid) taken to quantify the number of coccidial oocysts per gram of faeces (OpG). There were no differences between the groups in terms of body weight development (P > 0.05) and feed consumption. Kids of both groups were not able to consume enough feed to meet their nutrient requirements during the first 3 weeks following weaning. KEF had a lower frequency of OpG positive samples than CON (P = 0.043). Kefir did not affect the maximum oocyst excretion and age of the kids at the highest oocyst excretion (P > 0.05). KEF shed numerically 35% lower coccidial oocysts than the controls, which corresponded to a statistical tendency (P = 0.074) in lowering Log-OpG in comparison to CON. While KEF had a lower frequency of OpG positive samples and tended to shed lower OPG by around one-third, the frequency of diarrhea, level of highest oocyst excretion, and performance of the kids remained unaffected. Therefore, it is concluded that overall effects of kefir do not have a significant impact on sub-clinical infection and performance in weaned kids under relatively high-hygienic farming conditions
Organotin compounds in surface sediments of the Southern Baltic coastal zone: a study on the main factors for their accumulation and degradation
Abstract Sediment samples were collected in the Gulf of
Gdańsk, and the Vistula and Szczecin Lagoons—all located
in the coastal zone of the Southern Baltic Sea—just after the
total ban on using harmful organotins in antifouling paints on
ships came into force, to assess their butyltin and phenyltin
contamination extent. Altogether, 26 sampling stations were
chosen to account for different potential exposure to organotin
pollution and environmental conditions: from shallow and
well-oxygenated waters, shipping routes and river mouths,
to deep and anoxic sites. Additionally, the organic carbon
content, pigment content, and grain size of all the sediment
samples were determined, and some parameters of the nearbottom
water (oxygen content, salinity, temperature) were
measured as well. Total concentrations of butyltin compounds
ranged between 2 and 182 ng Sn g−1 d.w., whereas phenyltins
were below the detection limit. Sediments from the Gulf of
Gdańsk and Vistula Lagoon were found moderately contaminated
with tributyltin, whereas those from the Szczecin
Lagoon were ranked as highly contaminated. Butyltin degradation
indices prove a recent tributyltin input into the sediments
adjacent to sites used for dumping for dredged harbor
materials and for anchorage in the Gulf of Gdańsk (where two
big international ports are located), and into those collected in
the Szczecin Lagoon. Essential factors affecting the degradation
and distribution of organotins, based on significant correlations
between butyltins and environmental variables, were
found in the study area
Organotin compounds in surface sediments from seaports on the Gulf of Gdańsk (southern Baltic coast)
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