Immunisation of mice against neosporosis with recombinant NcSRS2 iscoms

The coccidian parasite Neospora caninum is an intracellular protozoan, causing abortion in cattle in many countries around the world. In this study, the protective potential of the major N. caninum surface antigen NcSRS2, expressed in Escherichia coli and formulated into immunostimulating complexes (iscoms), was investigated in an experimental mouse model. The recombinant protein was specially designed for binding to iscoms via biotin-streptavidin interaction. Two groups of 10 BALB/c mice were immunised twice, on days 0 and 28 with iscoms containing either the recombinant NcSRS2 (NcSRS2 iscoms) or similar iscoms with NcSRS2 substituted by an unrelated recombinant malaria peptide (M5) as a control (M5 iscoms). A third group of 10 age-matched BALB/c mice served as an uninfected control group. Immunisation with recombinant NcSRS2 iscoms resulted in production of substantial antibody titres against N. caninum antigen, while the mice immunised with M5 iscoms produced only very low levels of antibodies reacting with N. caninum antigen. After challenge infection with N. caninum tachyzoites on day 69, mice immunised with NcSRS2 iscoms showed only mild and transient symptoms, whereas the group immunised with M5 iscoms showed clinical symptoms until the end of the experiment at 31 days post inoculation. A competitive PCR assay detecting Nc5-repeats was applied to evaluate the level of parasite DNA in the brain. The amount of Nc5-repeats in the group vaccinated with NcSRS2 iscoms was significantly lower than in the control group given M5 iscoms. In conclusion, it was found that the recombinant NcSRS2 iscoms induced specific antibodies to native NcSRS2 and immunity sufficient to reduce the proliferation of N. caninum in the brains of immunised mice.     

Asaisonalität bei Bergschafen*

ZUSAMMENFASSUNG: Felddaten vom Tiroler Bergschaf (TB, n = 9849) und dem Wei?en Bayerischen Bergschaf (WB, n = 1448) wurden hinsichtlich Erstlammalter und Zwischenlammzeit ausgewertet, ebenso wie Vergleichs- untersuchungen zwischen Merinolandschaf (n = 125) und TB (n = 95) der Versuchsstation Neu- Ulrichstein (Hessen). Aus Blutplasma-Progesteronspiegel und Suchbockreaktionen ergaben sich Daten über die Zyklizit?t von 26 Wei?en Bergschafen. TB und WB unterscheiden sich nur unwesentlich in Zwischenlammzeit (240 Tage etwa) und Erstlammalter (490 Tage). Es ergaben sich signifikante Einflüsse von Jahr und Saison, Lammnummer und Betrieb. Die Bergschafe stehen in sehr kleinen Herden, mit zweimaliger Schur. Wegen der Gefahr von L?mmerverlusten durch Adlerschlag wird bei gealpten Schafen eine Sommerablammung verhindert. Die Alpung hat aber tendenziell eine positive Auswirkung auf die Asaisonalit?t. Wiederholbarkeiten der Zwischenlammzeit belaufen sich auf etwa 0,2, die Heritabilit?tswerte aus Halbgeschwister?hnlichkeit liegen ebenfalls in diesem Bereich, sie sind aber deutlich niedriger bei Tochter-Mutter-Beziehungen. Für das Erstlammalter ergab sich eine Heritabilit?t von 0,6. Im Vergleich zum Merinolandschaf ist das Bergschaf deutlich st?rker asaisonal, was sich in kürzerer Zwischenlammzeit (um 35 Tage) nach Winter- und Frühjahrsablammung und einer gleichm??igeren Verteilung der Ablammung über das Jahr manifestiert. Geschlechtsreife tritt etwa bei 9,5 Monaten bei einem K?rpergewicht von 43 kg auf. Die ovulatorische Periode setzt Ende April ein und endet nicht vor Januar. Das Bergschaf scheint eine geringere Sequenz von Langtagen zur Beendigung der anovulatorischen Periode zu ben?tigen. SUMMARY: Aseasonality in 'Bergschaf' Age at first lambing (ELA) and lambing interval (ZLZ) were analysed in 9849 records of the Tyrolean Bergschaf (TB) and in 1448 of the German Wei?e Bergschaf (WB). Bergschafe and German Merino Landschafe were compared for these traits (125 and 95 respectively) in the Hessian experiment station Neu-Ulrichstein and cyclicity was studied in 26 WB via plasma progesteron levels and search ram at Weihenstephan. ELA (490 days) and ZLZ (240 days) showed little difference between TB and WB. However, effects of year, season, parity and farm were statistically significant. TB are compared in small herds, are shorn twice yearly and are put on to mountain pastures in summer. To avoid lamb losses due to eagles, summer lambing is reduced in problem pastures which affects aseasonality in a favourable manner. The repeatability of ZLZ was about 0.2, as were heritabilities estimated from halfsib correlations, while dam-daughter correlations gave lower values. For ELA, h(2) was around 0.6. Compared with Merinos, the Bergschaf is definitely more aseasonal which results in shorter ZLZ (by 35 days) and a more uniform distribution of lambing. Sexual maturity occurs at about 9.5 months at 43 kg body weight. The ovulatory period starts in late April and lasts into January. The Bergschaf requires shorter sequences of long days to end the anovulatory period.     

Description ofPauesia (Pauesia)anatolica (Hymenoptera: Braconidae, Aphidiinae) sp. nov., a parasitoid of the cedar aphidCinara cedri

The first parasitoid species reared from a population of the cedar aphid,Cinara cedri Mimeur, 1935 (Hemiptera: Aphididae), from the peninsula of Anatolia in Turkey is described.Pauesia anatolica (Hymenoptera: Braconidae, Aphidiinae) is closely related to some species of thelaricis group ofPauesia from which it differs in the number of antenomers, the propodeum and features of the female genitalia. Its potential use as a natural enemy in areas where the aphid has been introduced is discussed. http://www.phytoparasitica.org posting Aug. 28, 2005.     

Inheritance of morphological characters and glycoalkaloids in potatoes of somatic hybrids between dihaploid Solanum acauleand tetraploid Solanum tuberosum.

Steroidal glycoalkaloids occur in potatoes and are reported to impart resistance to phytopathogens including bacteria, fungi, and insects. Because glycoalkaloids can be passed to progenies during breeding programs designed to develop improved potatoes, it is of importance to determine the quality of desired characteristics and the composition of glycoalkaloids of new somatic hybrids. The objective of this study was to determine the appearance, size, and shape (morphological characters) as well as the glycoalkaloid content of potato tubers of somatic hybrids between tetraploid Solanum tuberosum cv. Dejima (2n = 4x = 48 chromosomes) and the dihaploid clone ATDH-1 (2n = 2x = 24 chromosomes) induced by anther culture from Solanum acuale-T (acl-T, 2n = 4x = 48 chromosomes). Tuber size and shape in somatic hybrids were in accord with those of cv. Dejima, whereas the tuber skin color resembled that of ATDH-1. Thin-layer chromatography, high-performance liquid chromatography, and gas-liquid chromatography/mass spectrometry studies showed that the two steroidal glycoalkaloids (alpha-chaconine and alpha-solanine) were present in the tubers of S. tuberosum, whereas acl-T and ATDH-1 tubers were found to contain alpha-tomatine and demissine. The concentrations of total glycoalkaloids in both acl-T and ATDH-1 was >100 mg/100 g of fresh weight tuber cortex, much higher than in S. tuberosum. All somatic hybrids, except one clone, contained four glycoalkaloids (alpha-chaconine, alpha-solanine, alpha-tomatine, and demissine) derived from the fusion parents. The lack of alpha-tomatine in the remaining clone may be due to somaclonal variation. The results show that character expression is influenced by ploidy level and that total glycoalkaloid levels in most somatic hybrids were intermediate between those of the fusion parents. The possible significance of these findings for plant breeding and food safety is discussed.     

Field study indicating susceptibility differences between salmonid species and their lineages to proliferative kidney disease

Tetracapsuloides bryosalmonae (Myxozoa: Malacosporea) is the causative agent of proliferative kidney disease (PKD), which affects both wild and farmed salmonid fish. The objective of this study was to outline differences in susceptibility to PKD in different salmonid species, hybrids and breeding lineages. Susceptibility to T. bryosalmonae infection was established based on cumulative mortality, pathological findings and detection of T. bryosalmonae in the kidney using immunohistochemistry and molecular methods. Determination of pure and hybrid individuals of different species in the genus Salvelinus, and dissimilarity of rainbow trout lineages, was performed using traditional polymerase chain reaction (PCR) and microsatellite analyses. Rainbow trout displayed higher disease severity compared with brook trout and Alsatian charr. Moreover, the results indicated differences in infection susceptibility, not only among different salmonid species but also among different lineages of charr and rainbow trout. Our study indicated that some salmonid species and even different lineages of the same species are more suitable for farming under PKD pressure.     

Geography limits island small‐scale fishery production

Interacting social and ecological processes shape productivity and sustainability of island small‐scale fisheries (SSF). Understanding limits to productivity through historical catches help frame future expectations and management strategies, but SSF are dispersed and unaccounted, so long‐term standardized data are largely absent for such analyses. We analysed 40 years of trade statistics of a SSF product that enter international markets (sea cucumber) from 14 Pacific Island Countries and Territories (PICT) against response variables to test predictors of fishery production: (i) scale, (ii) productivity and (iii) socio‐economics. Combined production in PICT peaked over 20 years ago, driven by exploitation trends in Melanesia that accounted for 90% of all production since 1971. The size of island fisheries (as measured by total exports), and the duration and magnitude of fishery booms were most influenced by ungovernable environmental variables, in particular land area. The large and high islands of Melanesia sustained larger booms over longer periods than atoll nations. We hypothesize that land area is a proxy for land‐based nutrient availability and habitat diversity, and therefore the productivity of the shallow water areas where SSF are operating. PICT need to tailor management based on the intrinsic productivity of shallow inshore habitats: harvests from atoll nations will need to be smaller per unit area than at the high islands. Particularly countries with low productivity fisheries must consider the crucial economic “safety nets” that export SSF make up for dispersed island populations and incorporate them into broader development and island resilience strategies.