Natural variation in avenin epitopes among oat varieties: Implications for celiac disease

Celiac disease (CD) is a chronic inflammatory disease affecting the small intestinal mucosa. The causative agents have been identified as gluten proteins from wheat, barley, and rye, and the only available treatment for CD patients is a lifelong gluten-free diet. Non-gluten containing cereals would be a valuable contribution to the gluten-free diet. In this respect, oats are a good choice. However, commercial lots of oat flakes and flour frequently are contaminated with wheat, barley, and rye, and two studies have reported that some peptides derived from the gluten-like avenin storage proteins of oat can trigger an immune response in some CD patients. In the present study we have initiated the investigation whether all oat varieties contain similar amounts of potentially harmful sequences by biochemical and immunological methods. We confirm that commercial oat preparations are contaminated with other cereals that contain gluten or gluten-like proteins. Moreover, our results demonstrate that contamination-free oat varieties differ in their capacity to stimulate an avenin-sensitive gamma-gliadin specific T cell line derived from a patient with CD, indicative for differences in the two known avenin epitopes among oat varieties, implying that selection and breeding of completely safe oat varieties for all CD patients may be a realistic possibility.     

Detection of rotavirus in faecal specimens with a monoclonal antibody enzyme-linked immunosorbent assay: Comparison with polyclonal antibody enzyme immuno-assays and a latex agglutination test

Monoclonal antibodies have been produced against the 81/36F strain of rotavirus. One of them, was chosen as diagnostic reagent: it showed high ELISA reactivity with all the bovine, human and porcine rotavirus strains tested and reacted with VP6, structural protein product known to support the common rotavirus antigen.

A sandwich ELISA procedure using the chosen monoclonal as “capture and detecting” antibody was performed to detect rotavirus in faecal samples from experimentally inoculated newborn calves: it always gave a negative response with meconium and a positive response for the stool specimens which rotavirus have been isolated. This assay was compared with Enzygnost and Slidex Rota Kit tests and with a non-commercial sandwich ELISA test using polyclonal antibodies: it showed more sensitivity than the agglutination test and was as sensitive as the other two tests to detect rotavirus in routine diagnostic material. The test evaluated showed no equivocal results.     

Observations on mouse-infective stocks of Cowdria ruminantium: attempts to demonstrate persistence of the organism in mice immune to the Kwanyanga stock

Mice immunised against the Kwanyanga stock of Cowdria ruminantium by infection and treated with oxytetracycline proved immune to challenge on day 40 and also to a second challenge on day 125 after infection. Treatment with the experimental dithiosemicarbazone gloxazone on days 59 and 73 did not abolish immunity to challenge on day 125. No persistence of the organism in immune mice that had been challenged on day 40 could be demonstrated by subinoculating blood and liver homogenate on day 126. These results are different from findings reported elsewhere with the mouse-infective Kumm stock.     

Ceuthorrhynchus suturalis,een voor uien schadelijke snuitkever

Summary In 1960Ceuthorrhynchus suturalis F., the onion weevil, was very abundant in onion fields in the south-western part of the Netherlands. PreviouslyLli (1954) in Yugoslavia andJancke & Nietzke (1939) andRogoll (1959) in East-Germany have studied this pest.Investigations on the biology and the control of the weevil in the Netherlands have given the following results. In early spring the weevils concentrate on the young onion crops, feeding on the leaves. Their feeding may cause serious damage to the plants (fig. 3). At a later stage of development of the plants the weevils oviposit in the leaves, mainly towards the tips. The larvae which hatch from the eggs, are free-living in the hollow leaves (fig. 1). They feed upon the leaf tissue with the exception of the epidermis, and cause transparent oblong spots, similar to those caused by the larvae ofAcrolepia assectella Zell. (fig. 2). The larvae pupate in the surface layers of the soil. After emergence the adult weevils remain for some days in the onion fields, feeding on the leaves. They then migrate to hibernate elsewhere.C. suturalis has only one generation a year.The young onion plants should be sprayed as soon as the damage caused by the weevils becomes visible. Plants in later stages of development should also be sprayed, if many transparent spots are present.The weevils are very susceptible to Gusathion. This insecticide should be used at a dosage of 300 g active ingredient per hectare. The larvae too are very susceptible to this insecticide (tables 1, 2 and 3); they are less susceptible to insecticides containing N-methylnaphthylcarbamate. The latter chemical has to be used at a dosage of 750 g active ingredient per hectare. To obtain a uniform cover of the plants it is advisable to apply the insecticide in a minimum amount of 500 liter of spray liquid per hectare and to add a detergent if not already present.     

Three groups of Babesia canis distinguished and a proposal for nomenclature

Summary

Two stocks of large Babesiae from dogs originating in France, transmitted by Dermacentor reticulatus, two from North Africa, having Rhipicephalus sanguineus as vector, and one from South Africa, transmitted by Haemaphysalis leachi, were compared in cross‐immunity tests in dogs and in the indirect fluorescent antibody test (IFAT).

The French and North African stocks did not immunise against the South African one, while the North African stocks did not protect against a French one. The South African stock partially protected against a French one.

The three groups could be clearly distinguished in the IFAT These differences have practical implications for existing and future vaccines against canine babesiosis and for the serological diagnosis of atypical and chronic cases.

It is proposed to use a trinomial system of nomenclature for these groups: Babesia canis canis (Piana and Galli‐Valerio, 1895), Babesia canis vogeli Reichenow, 1937, and Babesia canis rossi (Nuttall, 1910), having Dermacentor, Rhipicephalus and Haemaphysalis ticks as their vectors respectively.     

The indirect fluorescent antibody test for bovine anaplasmosis

Summary

An indirect fluorescent antibody test was used succesfully for the serodiagnosis of experimental Anaplasma infections in cattle. Specific antibodies were detected three to ten days after anaplasma bodies werd found in the blood, and persistedat least 15 weeks post‐infection.

An American and an African stock of A. marginale were used to prepare antigens, and gave comparable results when tested on sera positive to either of these stocks, as well as to an A. centrale‐like stock from Korea.

There were no cross‐reactions with several Theileria, Babesia, Trypanosoma and Eperythrozoon species.     

Salmonella infections in finishing pigs in The Netherlands: bacteriological herd prevalence, serogroup and antibiotic resistance of isolates and risk factors for infection.

Salmonellae are wide spread in man and animals world wide and are of increasing significance as causative agents of foodborne diseases in man. The European Union, national authorities and the pig industry are therefore more and more interested in the Salmonella status of the pig population. The aim of this study was to estimate the bacteriological prevalence of Salmonella in finishing pig herds, the serogroup and the resistance to antibiotics of the isolated Salmonellae and a preliminary risk analysis of factors associated with infection. For this, 317 finishing pig herds were randomly selected from a database containing 1500 herds in the southern part of the Netherlands. In each herd 24 samples of fresh faeces were collected from two compartments with pigs close to market weight. Per compartment 12 samples of faeces were pooled into one pooled sample. Pooled samples were cultured in duplicate. Salmonella spp. were recovered from 71 out of 306 herds (23%) in which two compartments could be sampled. A total of 108 isolated Salmonella's were serotyped: 71 serogroup B, 3 serogroup C1, 6 serogroup C2, 22 serogroup D1, and 6 isolates neither serogroup B, C or D1. Of a total of 115 Salmonella isolates tested, none were resistant to colistin, enrofloxacin, flumequin or gentamicin. Automated liquid feeding of by-products, and membership of an Integrated Quality Control (IQC) production group were associated with a decreased risk of infection, while use of trough feeding was associated with an increased risk of infection. It is necessary to test these presumed risk factors in intervention studies to evaluate their potency to reduce the Salmonella prevalence in finishing pigs and thereby reduce the risk of Salmonellosis in people consuming pork.     

Theileria orientalis, a cosmopolitan blood parasite of cattle: demonstration of the schizont stage

Serological and morphological comparison of Theileria orientalis stocks from Australia, Britain, Iran, Japan and the USA with a more pathogenic stock from Korea, corresponding to T sergenti of Russian literature, showed that they all belong to one species, for which the name T orientalis is recommended. T orientalis is now known to occur on all continents. Macroschizonts and microschizonts, found in some of the calves infected with the Korean stock, are described and illustrated. Infections with the Korean stock were associated with early hyperthermia during the period schizonts are found, and commonly with high parasitaemias and anaemia even in unsplenectomised calves. The higher pathogenicity of this stock may be related to a faster rate of division. T orientalis may cause latent infection in sheep. With the exception of the stock from the USA, all stocks could be transstadially transmitted by Haemaphysalis longicornis and, or, H punctata.     

Stage-specific antigenicity in Theileria annulata: a case report

Blood from sick cattle in Bahrain transmitted piroplasms of Theileria annulata to a splenectomized calf. Larvae of Hyalomma anatolicum anatolicum were infected on the calf and, after moulting, induced clinical theileriosis, associated with numerous schizonts, in the same calf. The animal was cured by specific treatment. Antigenic differences thus shown between piroplasms on the one hand, and sporozoites and schizonts on the other hand, were confirmed in the indirect fluorescent antibody test, as a significant titre to T. annulata piroplasm antigen developed after the inoculation of blood, but to schizont antigen only after the infective ticks had induced the appearance of schizonts.