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1.
The influence of mesoscale weather patterns on the chemical composition of daily precipitation samples is analysed. The data of pH, sulphur from sulphates and total nitrogen are analysed for two rural sites: Plitvice station in forested part of Central Croatia (1981 to 1990) and Puntijarka suburban station on the mountain near Zagreb, the capital of Croatia (1982–1991). The two prevailing weather types in precipitation days are selected and the comparison of chemical composition of precipitation is made for each of them. The frequency distributions of pH, sulphur and nitrogen show that concentration of major ions in precipitation apparently depends on the regional scale weather type. It is shown that the seasonal variation of deposition is related to the seasonal variation in precipitation amount. In both weather types Plitvice receives more pollution than Puntijarka that is closer to urban and industrial pollution sources. Both locations are under the prevailing influence of regional pollution sources. 相似文献
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V. E. Ostland P. J. Byrne J. S. Lumsden D. D. MacPhee J. A. Derksen M. Haulena K. Skar E. Myhr H. W. Ferguson 《Journal of fish diseases》1999,22(5):351-358
An unusual form of bacterial gill disease (BGD) was identified which affected five species of cultured salmonids from Canada (i.e. rainbow trout, chinook salmon and Atlantic salmon), Norway (i.e. brown trout) and Chile (i.e. coho salmon). All outbreaks occurred at low water temperatures (< 10 °C) and with clinical presentations distinct from classical BGD, which is caused by Flavobacterium branchiophilum. In contrast to classical BGD, fish did not show marked respiratory distress with flaring of the opercula, the animals did not orientate at the surface of the water column near inflow water or at the margins of the tanks, and the feed response of the fish was varied. While mortality was increased, it was not precipitous as in classical BGD. Eight outbreaks were examined in greater detail using histopathology, scanning electron microscopy, bacteriology and immunohistochemistry. Large numbers of small bacterial rods were seen adhering to the lamellar epithelium of affected gills from all outbreaks. Histologically, the lamellar epithelium appeared swollen, often with evidence of single cell degeneration and exfoliation. In more severe instances, the formation of lamellar synechiae was seen, usually associated with sequestration of bacteria between fused lamellae. By contrast with typical BGD, overt epithelial hyperplasia, lamellar fusion and filamental clubbing were not common sequelae to infection; instead, the end result was shortened and somewhat stubby lamellae covered with swollen epithelial cells. The predominant bacterium recovered from affected gills was a small, Gram-negative, motile, fluorescent pigment-producing rod that shared phenotypic characteristics with Pseudomonas fluorescens. Polyclonal antisera prepared against three representative isolates indicated a weak antigenic similarity among them. Immunohistochemistry corroborated this finding, in that the antisera reacted strongly with gill sections containing the homologous bacteria, but not against morphologically similar bacteria in heterologous sections. A Gram-negative, yellow pigmented bacterium (YPB), identified as Flavobacterium psychrophilum, was also recovered, but only from the gills in the Ontario outbreaks. Antiserum prepared against this YPB indicated an antigenic similarity among isolates recovered from the Ontario outbreaks, but immunohistochemistry failed to recognize antigenically related bacteria on the gills of fish from the other outbreaks. Based on the unusual clinical presentation and the histopathological appearance of the gills, in conjunction with the absence of filamentous bacteria associated with and recovered from affected gills, the present authors have called this condition ‘atypical bacterial gill disease’ or ABGD. 相似文献
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Monitoring of libido and semen quality parameters in melatonin‐treated French alpine bucks during the non‐breeding season 
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下载免费PDF全文 H Valpotić V Berta S Milinković‐Tur M Samardžija J Grizelj B Špoljarić D Đuričić I Nazansky I Žura Žaja 《Reproduction in domestic animals》2017,52(6):953-961
The aim of this study was to investigate the effects of exogenous melatonin on libido and semen quality parameters in bucks during the non‐breeding season. Twelve bucks of the French alpine breed from 1.5 to 4 years of age were assigned into melatonin (MG) and control (CG) groups, with 6 bucks in each group. The experimental period was 3 months (March–May), divided into six periods of 15 days each. The bucks in the MG group received four melatonin implants at the end of March. Two semen samples were taken from the bucks by artificial vagina once per week and their libido estimated. Volume and spermatozoa concentration, their mass motility and motility, proportion of live and total abnormal and forms with abnormal head and tail were determined in the obtained ejaculate samples. The total number of spermatozoa and functional spermatozoa fraction in the ejaculate was also calculated. The MG bucks had significantly higher mass motility and motility of spermatozoa in the first half of April, and a higher proportion of live spermatozoa in the first and second half of April (p < .05). Differences in libido intensity were not significant. The results indicated that the application of melatonin significantly improved the qualitative parameters of semen in bucks, as seen in increased mass motility, motility of spermatozoa and proportion of live spermatozoa shortly following melatonin insertion. Therefore, the results of the current study are novel regarding the use of melatonin treatment during the non‐breeding season to improve the qualitative parameters of ejaculates in bucks. 相似文献
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The impact of the chromium supplementation on insulin signalling pathway in different tissues and milk yield in dairy cows 下载免费PDF全文
下载免费PDF全文 M. Pantelić L. J. Jovanović R. Prodanović I. Vujanac M. Đurić T. Ćulafić S. Vranješ‐Đurić G. Korićanac D. Kirovski 《Journal of animal physiology and animal nutrition》2018,102(1):41-55
Thirty days before expected time of parturition, 20 Holstein cows were divided into ?Cr and +Cr groups. From day 25 before parturition (BP ) up to day 30 after parturition (AP ), +Cr cows received 10 mg of Cr (chromium‐enriched yeast) daily. Muscle and adipose tissue samples were taken at days ?30, ?10, +7 and +10 related to parturition, when body condition score (BCS ) was also determined. Hepatic tissue samples were taken at days ?10 and +7. Tissue samples were used for determination of the insulin signalling pathway protein expressions. Intravenous glucose tolerance test (IVGTT ) was performed at days ?28, ?7, +10 and +30. Milk yield was recorded during first 14 weeks AP . Milk composition was obtained at days 7 and 28 AP . At day 10 BP , protein content of β ‐subunit of insulin receptor (IR β ) was significantly higher (p ? 0.05) in muscle, and phosphorylation of insulin receptor substrate 1 at serine 307 (pIRS ‐1 Ser307) was significantly lower (p ? 0.05) in hepatic tissue of +Cr group. After parturition, pIRS ‐1 Ser307 was significantly lower in muscle tissue at days 7 and 28 (p ? 0.05 and p ? 0.001, respectively), while phosphorylation of Akt at serine 473 (pA kt Ser473) was significantly higher (p ? 0.01) in hepatic tissue at day 7 AP in +Cr group. Chromium had opposite effect on insulin kinetics during IVGTT s obtained BP and AP . Insulin secretion was significantly reduced at day 7 BP and significantly enhanced at day 10 AP , when NEFA concentration was also significantly increased. Milk yield and ECM value were depressed in +Cr group. DMI and BCS were significantly enhanced in +Cr group at day 7 BP . In conclusion, chromium modulates insulin signalling pathway in dairy cows, but targeted signalling molecules are different in antepartal then post‐partal period, probably due to duration of exposure to chromium and different energy status between those periods. 相似文献
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Edyta Halupecki Carlo Bazzi Susanne Jock Klaus Geider Damir Đermić Bogdan Cvjetković 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(4):435-440
Erwinia amylovora is the causative agent of fire blight, a destructive disease of rosaceous plants. The European population can be divided
into several subtypes according to differences in restriction fragment length polymorphism of the XbaI genomic DNA digest analysed with pulsed-field gel electrophoresis. This technique was also used to determine the genetic
relatedness of six Croatian isolates to the E. amylovora types found in the countries surrounding Croatia. The isolates belong to the Pt2 pattern type that is characteristic of the
East Mediterranean basin. All tested isolates gave essentially the same total cell protein pattern in SDS-polyacrylamide gel
electrophoresis. The number of short-sequence DNA repeats in plasmid pEA29 of six isolates was determined by PCR assays and
ranged from four to seven. The isolates examined showed high pathogenicity in immature pear fruits. Differences were also
revealed in microbiological assays such as amylovoran synthesis, levan formation, siderophore production and colour on coliform
medium. 相似文献
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Mechanisms regulating inter‐annual variability in zooplankton advection over the Lofoten shelf,implications for cod larvae survival 下载免费PDF全文
下载免费PDF全文 Boris Espinasse Vigdis Tverberg Sünnje L. Basedow Tore Hattermann Ole Anders Nøst Jon Albretsen Jofrid SkarĐhamar Ketil Eiane 《Fisheries Oceanography》2017,26(3):299-315
Variability in the availability of suitable prey (mainly nauplii stages of Calanus spp.) in the early life stages of cod is likely a significant contributor to the fluctuations in the year‐class strength in the Arcto Norwegian cod stock. We have investigated the origin of the Lofoten shelf population of Calanus using a particle tracking model approach based on velocity fields simulated from 2002 to 2012. By performing backwards simulations of trajectories from particles released on the Lofoten shelf in early spring, we assessed the relative contribution of potential Calanus sources, such as the Lofoten Basin, the local overwintering on the continental shelf and the adjacent fjords. This analysis revealed significant interannual differences in advection patterns mainly driven by changes in wind conditions and variable strength of the Norwegian Coastal Current. Most of the particles advected into our study area originated on the shelf, and contrary to expectations, only a few originated from the Lofoten Basin where Calanus abundances tend to be high. These results suggest that contribution from the Lofoten Basin to the early spring shelf Calanus population may be overestimated and that contribution from more local sources, especially from adjacent fjords, may play a more important role than what has been previously anticipated. Our results highlight the necessity to improve quantification of shelf‐fjord exchange processes, as these may contribute more to the regulation of spring zooplankton stocks on the northern Norwegian shelf, and, as a result, may affect the survival of cod larvae in this area. 相似文献
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I. Alić T. Trbojević Vukičević M. Đuras S. Kužir G. Fazarinc V. Gjurčević Kantura 《Anatomia, histologia, embryologia》2014,43(1):16-21
Muscle variations take the form of additional muscle bundle or belly, unusual muscle origin or termination, as well as complete muscle absence. Knowledge of such variations not only has clinical importance for guiding surgery, but also can help reveal phylogenetic relationships. To improve our understanding of muscle variations in dogs, 57 medium‐sized, cross‐breed male and female adult animals were dissected as part of a gross anatomy course between 2005 and 2011. Variations in pectoral girdle muscles were observed in 7 (12.3%) dogs and took the form of an additional muscle bundle in the brachiocephalicus muscle (n = 2), in the omotransversarius muscle (n = 2), in the cervical part of the rhomboideus muscle (n = 2) and in the cervical part of the serratus ventralis muscle (n = 1). Muscle variation was bilateral in only one dog; it involved the omotransversarius muscle. The variations did not seem to be sex dependent. Such variations can appear regularly in dogs and should be taken into consideration during anatomical dissection. 相似文献
10.
Tuta absoluta (Meyrick) (Lepidoptera,Gelechiidae) in the Republic of Srpska (Bosnia and Herzegovina)
Pheromone traps were placed in the market place in Banja Luka, and in greenhouses and open field tomato crops, on 13 September 2010 to determine the presence of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in Banja Luka region. Based on examination of traps, the presence of T. absoluta was confirmed for the first time in the Republic of Srpska. Only mines of Liriomyza species were found by examining leaves under a stereomicroscope. In 2011, pheromone traps were placed in greenhouses at several locations (Banja Luka, Prijedor, Novi Grad, Kozarska Dubica, Ljubinje and Trebinje) at the beginning of June, and in open fields in Bijeljina and Trebinje at the beginning of September. Examination of the traps was carried out at intervals of 15 days. A sample of 100 leaves, taken from 20 randomly selected plants, was examined in order to evaluate the intensity of the attack. The first adults were caught in greenhouses in Ljubinje and Trebinje on 18 June 2011; in open field crops in Bijeljina on 9 September 2011 and in Banja Luka on 5 October 2011. Adults were not captured in Prijedor, Novi Grad or Kozarska Dubica, and no mined leaves were observed. The intensity of attack was evaluated on the basis of active infestation (percentage of leaves with active mines compared with all mined leaves). The strongest intensity of active infestation was recorded in the open field crops in Trebinje, where 19% of leaves with active mines were found. 相似文献