Interacción planta-patógeno e identificación de QTL asociados a la resistencia a Podosphaera xanthii y a caracteres agronómicos en una población RIL (TGR-1551 x Bola de Oro) de Cucumis melo’

El melón (Cucumis melo L.) es una de las especies hortícolas más importantes de nuestro país, cuya producción se ve limitada por la presencia de patógenos y plagas. El oídio, causado por Podosphaera xanthii, es una de las enfermedades de naturaleza fúngica que afecta más frecuentemente al cultivo del melón, tanto al aire libre como en invernadero, reduciendo el rendimiento y la calidad de los frutos. La selección de material vegetal resistente y la identificación de los genes o QTL (regiones genómicas implicadas en el control de un carácter cuantitativo) implicados en esta resistencia permiten abordar programas de mejora genética encaminados a la obtención de variedades comerciales de melón resistentes a esta enfermedad. La disponibilidad de una población de líneas recombinantes (RIL) procedentes del cruce entre la entrada multirresistente ‘TGR-1551’ y el cultivar español ‘Bola de Oro’ ha permitido estimar la localización de QTL asociados a la resistencia a oídio y a un gran número caracteres morfológicos, así como conocer la respuesta a nivel tisular de varios genotipos de melón al desarrollo del hongo. De esta forma, se han identificado dos QTL para la resistencia a las razas 1, 2 y 5 de Podosphaera xanthii para cada uno de los tres ambientes evaluados (verano y otoño 2010 y primavera 2011) en el mapa de ligamiento de una población la RIL (F7:F8) del cruce ‘TGR-1551’ x ’Bola de Oro’. Uno de los QTL, Pm-R, se localizó en el grupo de ligamiento (GL) V, con un porcentaje de explicación de la variación fenotípica de 16.4 a 35.8, y el otro QTL, pm-r, en el GL XII con 8.1 a 37.3% de variación fenotípica explicada. Con respecto a localización de QTL asociados a caracteres morfológicos, se han identificado un total de 56 QTL para las dos evaluaciones realizadas. La mayoría de ellos fueron consistentes, observándose en ambos años en los mismos grupos de ligamiento en una localización genómica similar. Los GL más saturados fueron el II y el IV, con QTL en su mayoría relacionados con tamaño del fruto y del ovario. Los QTL vinculados a caracteres morfológicos que colocalizaron con los QTL asociados con la resistencia a oídio no presentaron efectos aditivos negativos. En cuanto a las interacciones observadas entre las razas 1, 2 y 5 de oídio y distintas entradas de melón, se pudieron distinguir interacciones compatibles e interacciones incompatibles de tipo post-haustorial. Dentro de las interacciones post-haustoriales se han detectado las de tipo I y II descritas en la literatura, así como también una respuesta tipo II más rápida y una tipo II más lenta. La observación de las respuestas de algunas de estas entradas de melón infectadas con Podosphaera xanthii a distintas temperaturas permitió concluir que esta variable puede dar lugar a fenotipos de interacción distintos en las mismas líneas infectadas. Esta información puede ser de utilidad en futuros programas de mejora para la obtención de líneas comerciales de calidad y resistentes a las razas 1, 2 y 5 de Podosphaera xanthii

First report on proliferative kidney disease (PKD) in marble trout (Salmo trutta marmoratus, Cuvier 1817)

Proliferative kidney disease is a hyperplastic response of the principal lymphoid tissue of salmonid fish infected by Tetracapsidoides bryosalmonae, a myxozoan parasite. This parasite affects many rainbow trout farms in Europe and North America. The disease has also been reported in other salmonids as well as in pike (Esox lucius) and grayling (Thymallus thymallus). In autumn 2000, an outbreak of PKD induced mortality in a group of marble trout (Salmo trutta marmoratus) juveniles reared in a farm in north-east Italy. The fish were intended to restock public waters. Diseased fish showed a lethargic behaviour, skin darkening, abdominal dilatation, gill anaemia and, after necroscopy, increase in volume and a pale colour of the kidney. All fishes subjected to histological examination showed a marked granulomatous interstitial nephritis, as well as foci of pancreatic and hepatic necrosis. The immunohistochemistry and PAS stain allowed visualisation of the extrasporogonic phase of the parasite Tetracapsuloides bryosalmonae in several tissues of the host. This is the first reported outbreak of PKD in marble trout, and should receive full attention since this species is potentially under risk of extinction

Setaria tundra, an emerging filarioid nematode in roe deer (Capreolus capreolus) in northeast Italy.

Coincidental with decades of warming (high temperature and humidity) in the sub-Arctic region of Europe, the mosquito-borne filarioid nematode Setaria tundra is now associated with emerging epidemic disease, resulting in morbidity and mortality for reindeer and moose. Similarly, roe deer is also target of this nematode, as documented in Denmark, Germany and Bulgary. In the early 2000s, S. tundra was first described in roe deer in Piedmont (north Italy). Aedes spp. mosquitoes seem to be the most competent vectors for S. tundra and little is known about its pathogenicity in roe deer. After a first report in 2013 of S. tundra in Friuli Venezia Giulia-FVG (northeast Italy) roe deers, during 2014-2016 an investigation was undertaken to evaluate the its presence in road-killed roe deer from the Gorizia province. Currently, parasitological dissections of 17 roe deer were performed. During the necropsy, nematode specimens (1 to 58 per host) were found in the abdominal cavity. Based on their morphology and biometrics, the nematodes recovered were identified as Setaria tundra and preserved in alcohol or cryopreserved for further analysis Moreover, pathological lesions were described, documented and damaged tissue samples were collected for histological evaluation. The prevalence of S. tundra in FVG roe deer population is 47.1%, mean intensity 11 (range 1-58) and mean abundance 5. The adult worms were located free in the abdominal cavity where tracks left by worm migration were also seen. Macroscopical lesions were polysierositis with thickening spleen and liver serosa with fibrinous deposition on surface of the abdominal organs. Whereas, histological lesions were diffuse serositis, granulomatous reactivity with Muller's giant cells and calcifications. In our study in FVG, this the first recognition of S. tundra and the alarming aspect has been that some road killed roe deers showed some significant pathological peritoneal changes

Including marine microalgae in European seabass (D. labrax) diets: effects on digestive-absorptive functions

Marine microalgae deserve increasing attention as fish feed ingredients or supplements, due to their nutritional value and functional properties. They were recently shown to improve intestinal morphophysiology, which is often challenged in fish fed diets high in protein-rich plant feedstuffs. The aim of this study was to evaluate the effects of supplemental dried marine microalgae on gut histology and expression of genes encoding brush border membrane enzymes and transporters, in E. sea bass fed diets low in fish meal and supplying substantial levels of plant protein feedstuffs. Two test diets (A1 and A2) were prepared by including a blend of Tisochrysis lutea and Tetraselmis suecica dried biomass (2:1 w:w ratio) to replace 15 and 45% fish meal protein and 10 and 30% fish lipid of a control diet (C+) containing 50:50 fish to vegetable protein and lipid ratios. A negative control (C-) preparation was also formulated with a 30:70 fish to vegetable protein ratio. One hundred and forty four sea bass (mean weight 204.3\ub10.78g) were divided among 12 tanks connected to a recirculating aquaculture system ensuring optimal rearing conditions (T, 23.8\ub0C; Salinity 30 ppt). Fish groups were fed the test diets to visual satiety over 105 days according to a randomized design with 3 replicates per dietary treatment. At the end of the trial, 6 fish per treatment were euthanized; the digestive tract removed, divided into pyloric caeca (PC), foregut (FG) and hindgut (HG) sections, and frozen in liquid N for gene expression analysis. Subsamples of gut tissue were also collected for histological evaluation. From histological analyses fish fed diet C- had the lowest villi thickness (P<0.05) while those given diets including microalgae, irrespective of the inclusion level, resulted in greater villi length than that observed in either positive or negative controls. Irrespective of the dietary treatment, gene expressions of sucrase-isomaltase, PepT1, Na+/K+-ATPase and APN were highest in the foregut. Regardless of the gut section, gene expression of the same enzymes-transporter was higher in fish fed microalgae-containing diets (P<0.05) when compared to both controls. The present results indicate that even at the lower dietary inclusion level investigated here, a mix of T. lutea e T. suecica resulted in potentially improved digestive-absorptive functions. Further studies are needed to understand the mechanisms underlying the observed positive effects of dietary microalgae addition

Rhabdomyosarcoma of Soft Tissues in an Adult Brook Trout (Salvelinus fontinalis)

This report describes a spontaneously arising rhabdomyosarcoma of soft tissues in a brook trout (Salvelinus fontinalis). The lesion was examined by means of histology, immunohistochemistry (IHC) and transmission electron microscopy (TEM). The cross-reactivity of the primary antibodies used in the IHC was investigated in silico using the Protein Blast system. Microscopically, the lesion appeared as a 'small round cell' undifferentiated sarcoma with rare myotube formation. IHC identified expression of sarcomeric actin and vimentin and these molecules showed the highest protein sequence identity. Lower protein sequence identity coincided with negative immunolabelling for desmin, MyoD1, myogenin and CD3. TEM revealed myofibrils, but without a defined sarcomeric architecture. The diagnosis of solid alveolar rhabdomyosarcoma of soft tissues was achieved on the basis of histological and ultrastructural finding

Comparative Therapeutic Effects of Natural Compounds Against Saprolegnia spp. (Oomycota) and Amyloodinium ocellatum (Dinophyceae)

The fish parasites Saprolegnia spp. (Oomycota) and Amyloodinium ocellatum (Dinophyceae) cause important losses in freshwater and marine aquaculture industry, respectively. The possible adverse effects of compounds used to control these parasites in aquaculture resulted in increased interest on the search for natural products with antiparasitic activity. In this work, eighteen plant-derived compounds (2\u2032,4\u2032-Dihydroxychalcone; 7-Hydroxyflavone; Artemisinin; Camphor (1R); Diallyl sulfide; Esculetin; Eucalyptol; Garlicin 80%; Harmalol hydrochloride dihydrate; Palmatine chloride; Piperine; Plumbagin; Resveratrol; Rosmarinic acid; Sclareolide; Tomatine, Umbelliferone, and Usnic Acid) have been tested in vitro. Sixteen of these were used to determine their effects on the gill cell line G1B (ATCC\uaeCRL-2536TM) and on the motility of viable dinospores of Amyloodinium ocellatum, and thirteen were screened for inhibitory activity against Saprolegnia spp. The cytotoxicity results on G1B cells determined that only two compounds (2\u2032,4\u2032-Dihydroxychalcone and Tomatine) exhibited dose-dependent toxic effects. The highest surveyed concentrations (0.1 and 0.01mM) reduced cell viability by 80%. Upon lowering the compound concentration the percentage of dead cells was lower than 20%. The same two compounds revealed to be potential antiparasitics by reducing in a dose-dependent manner the motility of A. ocellatum dinospores up to 100%. With respect to Saprolegnia, a Minimum Inhibitory Concentration was found for Tomatine (0.1mM), Piperine and Plumbagin (0.25mM), while 2\u2032,4\u2032-Dihydroxychalcone considerably slowed downmycelial growth for 24 h at a concentration of 0.1mM. Therefore, this research allowed to identify two compounds, Tomatine and 2\u2032,4\u2032-Dihydroxychalcone, effective against both parasites. These compounds could represent promising candidates for the treatment of amyloodiniosis and saprolegniosis in aquaculture. Nevertheless, further in vitro and in vivo tests are required in order to determine concentrations that are effective against the considered pathogens but at the same time safe for hosts, environment and consumers

Functional and morphological adaptations of the digestive system induced by domestication in cats.

Several studies have showed the macroscopic difference in the gastrointestinal tract between the European wildcat (Felis silvestris silvestris) and the domestic cat (Felis silvestris catus). Digestive system in the wildcat is shorter than in domestic species and this feature is considered distinctive in the taxonomic classification of subjects (Schauenberg et al. 1977). This study is a part of a large investigation regarding the microscopic anatomy of the gastrointestinal tract of European wildcat, associated to the study of intestinal microbiome. Its main purpose was to enhance knowledge about this species, to get a comparison with domestic cat, and to evaluate if and how domestication has influenced the functional and morphological development of this apparatus, also n n t ut\u2018s m roflor To this aim we collected, weighted and measured the gastrointestinal tract of twenty European wildcats. Afterwards, intestinal sections were sampled, treated and observed at the microscope in order to evaluate histological characteristics as the villi height and width, crypts depth and wall thickness. Moreover, we wanted to study the intestinal production of an apolipoprotein that is believed directly related to the development of hepatic steatosis, decreasing the amount of lipids deposited in the liver. For this purpose, liver specimens were collected and treated to study histologically the degree of vacuolar degeneration of hepatocytes. Data were analyzed and compared with those of the domestic cats coming from our database. In attempt to evaluate the microbiome, feces and rectal ampulla were collected and sent to the Texas A&M University for pyrosequencing analysis (data not shown). Results demonstrated significant differences in intestinal structure between F. catus and F. s. silvestris. Villi coming from domestic cats were significantly shorter (p<0.0001) and wider (p<0.0142) than in wildcats that showed crypts deeper (p<0.0009). Domestication has led to significant changes in adaptation regarding both behavior and diet. Several studies showed the correlation between diet changes (protein, carbohydrates, and fiber concentration) and morphological adaptation in the gut of different species (Altmann, 1972; Hampson, 1983; Goodlad et al., 1988; Pluske et al., 1996; Sritiawthai et al., 2013). Moreover, data from liver study showed that domestic cat has higher levels of apolipoprotein compared to the wild cat and that the percentage of lipids in the liver was lower in F. catus than in F. s. silvestris. Despite these results, the liver of domestic cat revealed a rate of steatosis higher than in wild cat. Indeed, this pathology proved to be almost absent in wild cats and can be explained by the different nature of the two species diet and microbiome composition. This study revealed that transition from a strictly-carnivorous diet (typical of the wild cat) to an omnivorous type, has modified the nutritional intake considerably and influenced the evolution of the digestive apparatus in domestic cat

News Insights into the Host-Parasite Interactions of Amyloodiniosis in European Sea Bass: A Multi-Modal Approach

Amyloodiniosis is a disease resulting from infestation by the ectoparasitic dinoflagellate Amyloodinium ocellatum (AO) and is a threat for fish species such as European sea bass (ESB, Dicentrarchus labrax), which are farmed in lagoon and land-based rearing sites. During the summer, when temperatures are highest, mortality rates can reach 100%, with serious impacts for the aquaculture industry. As no effective licensed therapies currently exist, this study was undertaken to improve knowledge of the biology of AO and of the host-parasite relationship between the protozoan and ESB, in order to formulate better prophylactic/therapeutic treatments targeting AO. To achieve this, a multi-modal study was performed involving a broad range of analytical modalities, including conventional histology (HIS), immunohistochemistry (IHC) and confocal laser scanning microscopy (CLSM). Gills and the oro-pharyngeal cavity were the primary sites of amyloodiniosis, with hyperplasia and cell degeneration more evident in severe infestations (HIS). Plasmacells and macrophages were localised by IHC and correlated with the parasite burden in a time-course experimental challenge. CLSM allowed reconstruction of the 3D morphology of infecting trophonts and suggested a protein composition for its anchoring and feeding structures. These findings provide a potential starting point for the development of new prophylactic/therapeutic controls

Faecal Cyathostomin Egg Count distribution and efficacy of anthelmintics against cyathostomins in Italy: a matter of geography?

Background: In the framework of a trial carried out in 2008 in Europe to evaluate the efficacy of major parasiticides against horse cyathostomins, pre- and/or post- treatment Faecal Egg Counts (FEC) were evaluated in a total of 84 yards and 2105 horses from nine different regions from the South, the Center, the North-Center and North-East of Italy. Specifically, on the basis of FECs of the horses present in each property, 60 out of the 84 yards were enrolled for a Faecal Egg Count Reduction Test (FECRT) using fenbendazole, pyrantel, ivermectin and moxidectin. Results: Of the 1646 horses bred in the 60 recruited yards, 416 animals had a FEC between 50 and 150 Eggs Per Gram (EPG) of faeces and 694 a FEC >150 EPG (i.e. with total of 1110 positive animals). Of the 1110 positive animals, those with the highest FECs (i.e. 988) were included in the FECRT.The FECRT for four anthelmintic compounds showed remarkable differences in terms of prevalence of reduced and equivocal efficacy against cyathostomins in the different areas of Italy. Administration of fenbendazole and pyrantel resulted in resistance present or suspected in about half of the yards examined while resistance to ivermectin was found in one yard from central Italy and suspected resistance was detected in three more yards, one in each the North, the Center and the South.Treatment with moxidectin was 100% effective in all yards examined. Conclusions: Cyathostomin populations in the South and the Center of Italy were more susceptible to fenbendazole and pyrantel than the populations present in the Center-North and North-Eastern areas of Italy. Fenbendazole and/or pyrantel were ineffective in almost all properties from the North of Italy. The reasons for such a difference among the Italian regions in terms of FECs and efficacy of antiparasitic drugs are discussed, together with the role that veterinarians, and horse owners and managers should have for effective worm control programs in this country

Multidisciplinary studies on a sick-leader syndrome-associated mass stranding of sperm whales (Physeter macrocephalus) along the Adriatic coast of Italy

Mass strandings of sperm whales (Physeter macrocephalus) are rare in the Mediterranean Sea. Nevertheless, in 2014 a pod of 7 specimens stranded alive along the Italian coast of the Central Adriatic Sea: 3 individuals died on the beach after a few hours due to internal damages induced by prolonged recumbency; the remaining 4 whales were refloated after great efforts. All the dead animals were genetically related females; one was pregnant. All the animals were infected by dolphin morbillivirus (DMV) and the pregnant whale was also affected by a severe nephropathy due to a large kidney stone. Other analyses ruled out other possible relevant factors related to weather conditions or human activities. The results of multidisciplinary post-mortem analyses revealed that the 7 sperm whales entered the Adriatic Sea encountering adverse weather conditions and then kept heading northward following the pregnant but sick leader of the pod, thereby reaching the stranding site. DMV infection most likely played a crucial role in impairing the health condition and orientation abilities of the whales. They did not steer back towards deeper waters, but eventually stranded along the Central Adriatic Sea coastline, a real trap for sperm whales