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Wild-animals can act as reservoirs for resistant bacteria and transfer of resistance genes in the environment. These genes can spread to livestock and human either directly by transmission of shared resistant bacteria, or by horizontal gene-transfer to environmental bacteria. To ascertain at what extent wild-animals carry resistance genes, eight faecal samples from buffalo, zebra and wildebeest from Ngorongoro Conservation Area (NCA) and Mikumi National Park (MNP), and four control samples from local zebu cattle grazing together with wildlife in NCA. The qPCR was carried on 14 antimicrobial resistance genes including tetracycline (tet(A), tet(B), 93 tet(C), tet(M), tet(O), tet(W), macrolide, lincosamide, streptogramin B (ermB, ermF), sulphonamide (sulI, sulII), beta-lactam (blaCTX-M-1 group, blaCMY-2, blaSHV) and glycopeptide (vanA). Samples from NCA, both wildlife and cattle were positive for 8 out of 14 resistance genes. The most prevalent genes were tet(W) and blaCMY-2 with the latter being of concern in encoding ESBL-type resistance. Three samples from Buffalo not interacting with cattle in MNP, were positive for tet(W) and blaCMY-2, and in addition for sulI. This suggests that wild ungulates on savannah, irrespective of contact with cattle, may constitute a reservoir for antimicrobial resistance determinants. Further studies are indicated to determine resistance gene-pool among wildlife animals. [ABSTRACT FROM AUTHOR]

Aims: To analyse and compare the effect of selection power for antimicrobial resistance (AMR) in coliforms of two kinds of β-lactams--aminopenicillins; ampicillin (Amp) and cephalosporins; cephalexin (Cpn) and ceftiofur (Cef)-- and tetracycline (Tet) using an approach based on a swine faecal microcosmos. Methods and Results: Sixteen faecal samples from 32 pigs (mixed two by two) were treated with Amp, Cpn, Cef and Tet for 6 h (T6h) at concentrations expected to reach the animals gut when using in vivo standard doses. Controls (no drug added) were also tested. Next, samples were 1 : 100 diluted and left under the same conditions (no antimicrobial added) for further 20 h (T20h). The proportion of resistant coliform bacteria (R coliforms) to each antimicrobial was analysed just before starting the treatment (T0), at T6h and at T20h. Coselection was also studied by replica plating. Treatment for 6 h yielded significant increase in proportion of R coliforms, regardless of the drug and lack of selection pressure showed different effects at T20h depending on the antimicrobial used. Selective pressure was associated with the type of the b-lactam with Amp selecting for significantly higher numbers of R coliforms than cephalosporins. Conclusions: AMR development was observed following short treatment, and for Amp and Tet treatment, resistance persisted 20 h beyond the interruption of treatment. An association between kind of b-lactam and power of selection was found. Significance and Impact of the Study: AMR represents a threat to human health globally and antimicrobial treatment of livestock has a direct impact on this problem. Through our approach based on a swine faecal microcosmos, we demonstrated the effect on AMR development of several drugs commonly used in livestock. Cephalosporins, representing last-line antimicrobials in human medicine, exerted lower selective pressure than Amp under the conditions used and yielded higher proportion of multidrug-R strains. [ABSTRACT FROM AUTHOR]

Gas dissolution reduces the release of methane to the atmosphere from subsea sources. Being able to predict and assess the methane flux to the atmosphere requires knowledge on gas dissolution and mass transfer. This can be obtained by studying the size evolution of bubbles rising in water. New data of bubble size evolution have been obtained by releasing, tracking, and filming methane bubbles with an ROV in the Trondheimsfjord from depths varying between 100 and 300 m. Released bubbles had an initial diameter between 5 and 7 mm and were tracked until they reached a diameter of roughly 2 mm. The new data were compared against theory, applying established correlations for the mass transfer coefficient. There was an inconsistency between experiment and theory. Thus, new correlations for the mass transfer are proposed. The new correlations are consistent with both the new experiments and previously published experiments. They indicate that the conditions in the ocean can be labeled as partly contaminated with respect to mass transfer. Plain Language Summary: Methane bubbles released from the ocean can reach the atmosphere and affect the methane concentration in the atmosphere. Methane is a potent greenhouse gas and highly combustible. How much gas enters the atmosphere depends on how much gas is dissolved in the ocean. The shrinking of bubbles and the development of bubble size are signatures of the gas dissolution. There is a lack of knowledge on methane dissolution in seawater. An experiment outside Trondheim, Norway, has been conducted where an ROV released methane bubbles and recorded images of the bubbles as they rose upward. These images have been analyzed to shed light on gas dissolution. Key Points: ROV with cameras were employed to study methane bubbles rising in oceanSize evolution of rising methane bubbles is reportedData from bubble size evolution are applied to shed led light on gas dissolution and mass transfer coefficient [ABSTRACT FROM AUTHOR]

Presents information on a study which devised a modified internal reflection technique to permit the infrared spectroscopy of thin films of SiO[sub2] on silicon by eliminating the silicon substrate absorption and providing an optical amplification of three orders of magnitude. Experimental arrangement; Review of the theory of internal reflection; Evaluation of the effects of different oxide structures on the infrared spectra; Identification of the local bond configuration.

Abstract: Aim: The study aimed to isolate and characterize Enterococcus species from apparently healthy waste attendants, cattle and cattle waste in Tanzania. Emphasis was given to antimicrobial resistance and in particular occurrence of vancomycin (VA)‐resistant enterococci. Methods and Results: Faecal samples were collected from healthy cattle, cattle waste attendants and cattle house wastes, and isolation of Enterococcus species was performed using Slanetz Bartley agar. Isolates were characterized with regard to species, antimicrobial susceptibility and presence of VA resistance genes. Enterococcus faecalis was the most prevalent species from all sources of isolation (43·5%), followed by Enterococcus faecium (38·4%). Isolates of E. faecium showed a higher number of phenotypic antimicrobial resistance than isolates of E. faecalis. Fifty‐eight isolates, which showed resistance or intermediate resistance to VA by disc diffusion test, were analysed for VA‐resistant Enterococcus (VRE) by PCR. The vanA gene was detected in 14 isolates of E. faecium and 12 isolates of E. faecalis, while vanB was detected in three isolates. No isolates were found to carry vanC1‐gene. Conclusion: VRE was detected in both human and cattle samples, despite no known use of antimicrobial agents that can select for VRE in livestock in Tanzania. Enterococcus faecalis was the most commonly isolated species from cattle and humans. Significance and Impact of the Study: The study provides information on the prevalence of VRE in human and nonhuman samples in Tanzania calling for further studies on the origin of VRE in such isolates, since no selection mechanism in Tanzania are known. [ABSTRACT FROM AUTHOR]

Perennial plants growing at high latitudes synchronize growth and dormancy to appropriate seasons by sensing environmental cues. Autumnal growth cessation, bud set and dormancy induction are commonly driven by the length of photoperiod and light quality, and the responses are modified by temperature. However, although ultraviolet ( UV)- B radiation is well known to affect plant growth and development, information on the effects on bud phenology is scarce. We examined the separate and combined effects of enhanced temperature and UV- B on autumnal bud set and spring bud break in female and male clones of P opulus tremula in an outdoor experiment in Joensuu, Eastern Finland. Enhancements of UV- B and temperature were modulated to +30% and +2 °C, respectively, from June to October 2012. Enhanced UV- B accelerated bud set, while increased temperature delayed it. For both UV- B and temperature, we found sex-related differences in responsiveness. Temperature increase had a stronger delaying effect on bud maturation in male compared with female clones. Also, male clones were more responsive to UV- B increase than female clones. Increasing autumnal temperature enhanced bud break in spring for both sexes, while UV- B enhanced bud break in male clones. In conclusion, we found that UV- B affected phenological shifts in P . tremula, and that temperature and UV- B affected genders differently. [ABSTRACT FROM AUTHOR]

Salmonella enterica 4,[5],12:i:- is a monophasic variant of S. Typhimurium. In the last decade, its prevalence rose sharply. Although S. 4,[5],12:i:- and S. Typhimurium are known to pose a considerable public health risk, there is no detailed information on the circulation of these serovars in Italy, particularly as far as veterinary isolates are concerned. For this reason, a data set of 877 strains isolated in the north-east of Italy from foodstuffs, animals and environment was analysed during 2005-2010. The Random Forests (RF) method was used to identify the most important epidemiological and phenotypic variables to show the difference between the two serovars. Both descriptive analysis and RF revealed that S. 4,[5],12:i:- is less heterogeneous than S. Typhimurium. RF highlighted that phage type was the most important variable to differentiate the two serovars. The most common phage types identified for S. 4,[5],12:i:- were DT20a, U311 and DT193. The same phage types were also found in S. Typhimurium isolates, although with a much lower prevalence. DT7 and DT120 were ascribed to the two serovars at comparable levels. DT104, DT2 and DT99 were ascribed exclusively to S. Typhimurium, and almost all the other phage types identified were more related to the latter serovar. Such data confirm that phage typing can provide an indication of the biphasic or monophasic state of the strains investigated and could therefore support serotyping results. However, phage typing cannot be used as the definitive method to differentiate the two serovars, as part of the phage types were detected for both serovars and, in particular, all phage types found for S. 4,[5],12:i- were found also for S. Typhimurium. [ABSTRACT FROM AUTHOR]

Twelve-week-old indigenous chickens, either immune-suppressed using dexamethasone (IS) or non-immune-suppressed (NIS), were challenged with a low virulent strain, Pasteurella multocida strain NCTC 10322T, and developed clinical signs and pathological lesions typical of chronic fowl cholera. NIS birds demonstrated much more severe signs of fowl cholera than IS birds. With few exceptions, signs recorded in IS and NIS birds were of the same types, but significantly milder in the IS birds, indicating that immune suppression does not change the course of infection but rather the severity of signs in fowl cholera. P. multocida signals by fluorescent in situ hybridization (FISH) were observed between 1 h and 14 days in the lungs, trachea, air sacs, liver, spleen, bursa of Fabricius and caecal tonsils, while signals from other organs mostly were observed after 24 h. More organs had FISH signals in NIS birds than in IS birds and at higher frequency per organ. Many organs were positive by FISH even 14 days post infection, and it is suggested that these organs may be likely places for long-term carriage of P. multocida following infection. The present study has demonstrated the spread of P. multocida in different tissues in chickens and distribution of lesions associated with chronic fowl cholera, and pointed to a decrease of pathology in IS birds. Since dexamethasone mostly affects heterophils, the study suggests that these cells play a role in the development of lesions associated with chronic fowl cholera in chickens. [ABSTRACT FROM PUBLISHER]

Aims: The aim of the study was to investigate the flock prevalence of Campylobacter jejuni and Campylobacter coli in broiler farms in Lithuania and to identify possible persistent strains of Camp. jejuni using amplified fragment length polymorphism (AFLP) typing method. Methods and Results: During 1 year, 42 broiler flocks from 9 broiler farms were examined to determine the prevalence of Campylobacter-positive broiler flocks in Lithuania. Among 42 broiler flocks examined, 31 flocks (73·8%) were positive for Camp. jejuni and 17 flocks (40·48%) for Camp. coli. Campylobacter jejuni isolates were genotyped by AFLP method using BspDI and BglII restriction enzymes. Typing of 190 isolates generated 50 AFLP genotypes with the highest diversity of strains found in the summer season. Each farm showed one or more predominant AFLP types, and one AFLP type (A32) was found in five broiler farms over a 1-year period. Conclusions: Campylobacter jejuni and Camp. coli are highly prevalent in broiler farms in Lithuania. Farm-specific genotypes were identified in all farms examined. Type A32 was present and persisted in different broiler farms, and a common source of transmission of Camp. jejuni was suspected. Significance and Impact of the Study: For the first time, Camp. jejuni in broiler flocks has been genetically characterized in Lithuania. Persistent strains of Camp. jejuni were detected over one period at the beginning of broiler meat production chain and, therefore, the identification of contamination source of such strains and the mechanism of their particular ability to persist are crucial to establish effective control measures against Camp. jejuni infection in broiler farms. [ABSTRACT FROM AUTHOR]

Pasteurella multocida causes fowl cholera, a highly contagious and severe disease in chickens and water fowls. The disease is not well described in less intensive production systems, including scavenging family poultry production in developing countries. P. multocida was isolated from 25.9% of healthy-looking ducks and 6.2% of chickens from free-range family poultry farms and at slaughter slabs at market. On experimental infection with 1.2 to 2.0×108 organisms of the P. multocida type strain (NCTC 10322T), 12-week-old chickens expressed fowl cholera clinical signs significantly more times (372 signs) than those of 4-week-old, 8-week-old and 16-week-old chickens (173, 272 and 187 signs) and more signs were severe. In family ducks the 8-week-old birds expressed clinical signs significantly more times (188 signs) than those of the other age groups (117, 80, and 83 signs, respectively) and severe signs were more frequent. P. multocida transmitted from seeder birds (n=12) to sentinel birds (n=30), which developed clinical signs, and in some cases lesions of fowl cholera allowed bacterial re-isolation, whether infected ducks served as seeders for chickens or chickens served as seeder for ducks. This study has documented the occurrence of P. multocida among healthy-appearing family poultry in a tropical setting, and demonstrated that age susceptibility is highest in 12-week-old family chickens and 8-week-old family ducks when challenged with a low-virulent strain of P. multocida. It has further demonstrated that cross-transmission of fowl cholera may happen between family ducks and chickens, and vice versa. [ABSTRACT FROM AUTHOR]

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