A gel electrophoretic study of the protein and nucleic acid components of African horsesickness virus.

The physico-chemical structure of African horsesickness virus (AHSV) is compared with that of some of the other members of the Reoviridae, and in particular with that of bluetongue virus (BTV), the type strain of the orbivirus genus. This study adduces evidence of a great similarity between the gel electrophoretic patterns of the polypeptides of AHSV and BTV. The molecular mass values of the 7 AHSV polypeptides range between 0,30 x 10(5) and 1,46 x 10(5) dalton, a variation similar to that of BTV. The close relation between AHSV and BTV is further affirmed by the gel electrophoretic resolution of the AHSV double-stranded RNA genome into 10 segments.     

Mechanisms underlying Phalaris aquatica "sudden death" syndrome in sheep

Twenty outbreaks of Phalaris aquatica "sudden death" syndrome in sheep were investigated between 1981 and 1991. Four were confirmed and one was suspected, to be a cardiac disorder; 5 were confirmed and 3 were suspected, to be a polioencephalomalacic disorder; the aetiology of the remaining 7 outbreaks could not be determined. Potentially toxic levels of hydrocyanic acid (20 to 36 mg/100 g) were measured in the 3 toxic phalaris pastures tested. The measurement of potentially toxic levels of nitrate nitrogen (2920 micrograms/g) in toxic phalaris pastures by others, was noted. It is suggested that phalaris "sudden death" syndrome could have as many as 4 different underlying mechanisms, and that these might reflect the presence in the plant of a cardio-respiratory toxin, a thiaminase and amine co-substate, cyanogenic compounds, and nitrate compounds.     

Entwicklung einer Herbstprognose für den Erreger der Wurzelhals- und Stängelfaule Phoma lingam (Teleomorph: Leptosphaeria maculans)

Based on experimental data of oilseed rape monitoring in Schleswig-Holstein during the last seven years and actually established monitoring at four sites in Germany, a forecasting system for a determined autumn application against the important rape pathogen root collar (Phoma lingam; teleomorph: Leptosphaeria maculans) was developed. Early primary infections by ascospores in autumn are the elicitors of severe yield-reducing root collar epidemics, which depend on weather conditions, especially rainfall, leaf wetness and precipitation. Based on measured data and on trial weather records, a model was developed to predict the daily infection risk. Threshold values for a determined application were calculated based on disease incidence monitoring values. Applications predetermined from the calculated “daily infection value” reduced pathogen populations in autumn in comparison to the untreated control. Effects of the autumn treatments on root collar could be recorded; however, a significant yield effect occurred at one site only. Weather conditions over winter until vegetation start in the following year influence root collar severely. Due to this conclusion it is difficult to evaluate prosperous autumn treatments.     

Co‐culture of sea cucumber Holothuria scabra and red seaweed Kappaphycus striatum

Commercially valuable sea cucumbers are potential co‐culture species in tropical lagoon environments, where they may be integrated into established aquaculture areas used for seaweed farming. In the current study, wild‐caught juvenile sea cucumbers, Holothuria scabra, and red seaweed Kappaphycus striatum were co‐cultured on Zanzibar, United Republic of Tanzania. Sea cucumbers (97 g ± 31 SD, n = 52) were cultured in mesh enclosures at initial cage stocking densities of 124 ± 21 SD and 218 ± 16 SD g m^?2 under seaweed culture lines. Over 83 days, individual growth rate (1.6 g d^?1 ± 0.2 SD) of sea cucumbers at low stocking density was significantly higher (χ² = 8.292, d.f. = 1, P = 0.004) than at high‐stocking density (0.9 g d^?1 ± 0.1 SD). Seaweed individual growth rates [6.27 (±0.3 SE) g d^?1] were highest in co‐culture with sea cucumber at low density but did not differ significantly from high sea cucumber density or seaweed monoculture treatments (χ² = 3.0885, d.f. = 2, P = 0.2135). Seaweed growth varied significantly (χ² = 35.6, d.f. = 2, P < 0.0001) with sampling period, with the final sampling period resulting in the highest growth rate. Growth performance for seaweed and sea cucumbers (χ² = 3.089, d.f. = 2, P = 0.21 and χ² = 0.08, d.f. = 1, P = 0.777 respectively), did not differ significantly between monoculture and co‐culture treatments, yet growth in co‐culture was comparable with that reported for existing commercial monoculture. Results indicate H. scabra is a highly viable candidate species for lagoon co‐culture with seaweed. Co‐culture offers a more efficient use of limited coastal space over monoculture and is recommended as a potential coastal livelihood option for lagoon farmers in tropical regions.     

Eocene Patagonia fossils of the daisy family

Fossil capitula and pollen grains of Asteraceae from the Eocene of Patagonia, southern Argentina, exhibit morphological features recognized today in taxa, such as Mutisioideae and Carduoideae, that are phylogenetically close to the root of the asteracean tree. This fossil supports the hypothesis of a South American origin of Asteraceae and an Eocene age of divergence and suggests that an ancestral stock of Asteraceae may have formed part of a geoflora developed in southern Gondwana before the establishment of effective dispersal barriers within this landmass.     

Prevalence of AmpC‐ and Extended‐Spectrum β‐Lactamase‐Harbouring Enterobacteriaceae in Faecal Flora of a Healthy Domestic Canine Population

In order to estimate the prevalence of AmpC‐ and ESBL β‐lactamase‐producing Enterobacteriaceae in the faecal flora of a healthy domestic canine population, faecal samples were obtained from healthy dogs receiving routine parasitology screening at the Ohio State University Veterinary Medical Center, between January 2013 and April 2013. Samples were screened for the presence of AmpC and ESBL β‐lactamase phenotypes, and the clinically important genotypes, bla_CMY and bla_CTX‐M, were confirmed via conventional PCR. Minimum inhibitory concentrations were determined for isolates and plasmids were characterized. Two hundred and twelve canine faecal samples were screened, of which 30 harboured isolates carrying the AmpC bla_CMY, representing 14.2% of the population (95% CI: 9.4–18.9%). Nine samples harboured isolates that carried the ESBL bla_CTX‐M, representing 4.2% of the population (95% CI: 1.5–7.0%). Isolates containing bla_CMY harboured multiple plasmid replicon types, while isolates containing bla_CTX‐M harboured few plasmid replicon types. Our results suggest that domestic dogs may serve as a reservoir for extended‐spectrum cephalosporin resistance genes for other domestic animal populations as well as for their human companions. This represents a potential veterinary and public health risk that warrants further investigation and continued surveillance to ascertain the nature and extent of the risk. The high level of diversity of plasmid content among isolates harbouring bla_CMY suggests broader dissemination relative to bla_CTX‐M isolates.     

Neuroendocrine,Metabolic and Genomic Cues Signalling the Onset of Puberty in Females

Puberty is the result of a dynamic interaction between genetic factors and environmental cues, all of which lead to the attainment of reproductive capacity. Thus, significant changes in hormone secretion occur from the pre‐pubertal to the pubertal stage. The objective of this review is to provide an update of some endocrine, physiological, metabolic and genetic concepts involved in the establishment of the hypothalamic‐hypophyseal‐gonadal axis function promoting the onset of the reproductive function during puberty. To achieve this purpose, basic aspects of the function of the hypothalamic‐hypophyseal‐gonadal axis, the control of the axis by neurotransmitters and the interaction between reproductive function and metabolic status will be considered. Finally, the role of the novel kisspeptin system and the GPR54 receptor as modulators of puberty will be considered, in addition to the hierarchical expression of the main genes acting as regulators of the onset of puberty.     

Discrimination between sheep-associated and wildebeest-associated malignant catarrhal fever virus by means of a single-tube duplex nested PCR

A single-tube duplex nested polymerase chain reaction (sdn-PCR) was developed for the detection of and discrimination between ovine herpesvirus-2 (OvHV-2) and alcelaphine herpesvirus-1 (AIHV-1). These viruses respectively cause sheep- and wildebeest-associated malignant catarrhal fever (SA-MCF and WA-MCF). In the first step of the sdn-PCR, two primers with high annealing temperatures based on conserved regions of the tegument genes were used for DNA amplification. In the second step, two primer sets based on variable regions of the respective OvHV-2 and AIHV-1 genes and with annealing temperatures > 11 degrees C below the primers used in the first step, were used. Internal regions of different sizes from amplicons produced in the first step were amplified. This single-tube test obviates the need for two separate assays to detect both viral types, thereby reducing time, labour and cost.     

Survey of parasites and bacterial pathogens from free-living waterfowl in zoological settings

To determine if free-living waterfowl residing in a zoological setting pose health risks for its animal collections, visitors, and employees, 450 fecal samples were collected and cultured for the presence of Campylobacter jejuni, Escherichia coli, Salmonella spp., and Pasteurella multocida. A survey of endoparasites infecting the waterfowl was also conducted. Sixty-seven percent, 42%, and 1.7% of the samples tested positive for E. coli, C. jejuni, and Salmonella spp., respectively. No P. multocida was isolated from the sampled population. Antimicrobial susceptibility testing for the bacterial isolates demonstrated that a majority of the isolates were susceptible to the antibiotics tested. A survey for parasites revealed 16% of the samples had coccidia oocytes; 8% of the sample had spirurid ova; and 17% of the sample had strongylate-type nematode ova. Ascaris spp. ova, Capillaria spp. ova, oxyurid ova, and mites were also noted in some fecal samples.