Prevalence of anthelmintic resistance in gastrointestinal nematodes of sheep and goats in Norway

In the period of 2008–2009, the efficacies of the benzimidazole (BZ) albendazole and the macrocyclic lactone (ML) ivermectin against gastrointestinal nematodes (GIN) of small ruminants were evaluated by means of the fecal egg count reduction (FECR) test and by post-treatment identification of surviving third stage (L3) larvae after coproculture. Sheep (n = 28) and goat (n = 28) flocks from three areas of Norway were randomly selected to assess the prevalence of anthelmintic resistance (AR), whereas only lambs from non-randomly selected sheep flocks (n = 32) with a farm management that could select for AR were investigated the second year. Only flocks with a mean excretion of nematode eggs per gram feces (EPG) ≥150 at time of treatment were included in the survey. In total, 48 (80%) and 13 (46.4%) of the selected sheep and goat flocks, respectively, fulfilled the inclusion criteria. The proportions of flocks classified as resistant (i.e., FECR <95% and with a lower 95% confidence interval of <90%) for the BZ drug albendazole were 10.5% and 31.0% in the randomly and non-randomly selected sheep flocks, respectively. When restricting the area to Rogaland County, eight flocks out of ten (80%) non-randomly selected sheep flocks showed BZ resistance. The efficacy of ML was 100% in all surveyed sheep and goat flocks. In post-treatment coprocultures from the non-randomly selected flocks, the main nematode genera were Teladorsagia/Trichostrongylus in five flocks, Haemonchus in two flocks, and a mixture of these genera in the remaining two flocks. In the goat flocks, the pre-treatment infection levels of GIN were low compared to what was found in the sheep flocks. Still, in one flock, AR against BZ in Teladorsagia/Trichostrongylus was found. New strategies and recommendations to face the emerging AR situation in Rogaland County in order to limit the spread of resistant nematodes within and into other areas are urgently needed

Worm control practice against gastro-intestinal parasites in Norwegian sheep and goat flocks

<p>Abstract</p> <p>Background</p> <p>Anthelmintic treatment is the most common way of controlling nematode infections in ruminants. However, several countries have reported anthelmintic resistance (AR), representing a limitation for sustainable small ruminant production. The knowledge regarding worm control management represents a baseline to develop a guideline for preventing AR. The aim of the present study was therefore to improve our knowledge about the worm control practices in small ruminant flocks in Norway.</p> <p>Methods</p> <p>A questionnaire survey regarding worm control practices was performed in small ruminant flocks in Norway. Flocks were selected from the three main areas of small ruminant farming, i.e. the coastal, inland and northern areas. A total of 825 questionnaires, comprising 587 sheep flocks (return rate of 51.3%) and 238 goat flocks (52.6%) were included.</p> <p>Results</p> <p>The results indicated that visual appraisal of individual weight was the most common means of estimating the anthelmintic dose used in sheep (78.6%) and goat (85.1%) flocks. The mean yearly drenching rate in lambs and ewes were 2.5 ± 1.7 and 1.9 ± 1.1, respectively, whereas it was 1.0 (once a year) in goats. However, these figures were higher in sheep in the coastal area with a rate of 3.4 and 2.2 in lambs and ewes, respectively. Benzimidazoles were the predominant anthelmintic class used in sheep flocks (64.9% in 2007), whereas benzimidazoles and macrocyclic lactones were both equally used in dairy goat flocks. In the period of 2005-2007, 46.3% of the sheep flocks never changed the anthelmintic class. The dose and move strategy was practiced in 33.2% of the sheep flocks.</p> <p>Conclusions</p> <p>The present study showed that inaccurate weight calculation gives a risk of under-dosing in over 90% of the sheep and goat flocks in Norway. Taken together with a high treatment frequency in lambs, a lack of anthelmintic class rotation and the common use of a dose-and-move strategy, a real danger for development of anthelmintic resistance (AR) seems to exist in Norwegian sheep and goat flocks. This risk seems particularly high in coastal areas where high treatment frequencies in lambs were recorded.</p

Exposure to pasture borne nematodes affects individual milk yield in Swedish dairy herds

The association between exposure to gastrointestinal nematode (GIN) parasitism, indicated by elevated individual optical density ratio (ODR) to Ostertagia ostertagi, and individual milk production was analysed in dairy cows. The multivariable analysis also accounted for other sources of variation than exposure to GIN parasitism. Intra- and inter-herd variation in parasite exposure was also evaluated. Organic and conventional herds located in south-east Sweden (13 herds per system) were visited during the housing period 2009-2010. Levels of all major pasture-borne helminths in Sweden (O. ostertagi, Fasciola hepatica and Dictyocaulus viviparus) were determined in bulk tank milk, cow milk and serum (only for O. ostertagi). Their specific antibodies were detected using three different ELISAs (Svanova Biotech) and the optical density of the sample was expressed as ODR. Positive cases of Dictyocaulus and Fasciola were seldom found. Variation in ODR in serum samples for Ostertagia was higher within herds than between herds. Correlations between ODR for Ostertagia in serum and milk parameters were significant and negative. In the multivariable analysis, two models were performed separating data from primiparous and multiparous cows. Results from mixed models showed that daily milk yield was significantly influenced by Ostertagia ODR for multiparous cows. No interactions were found between Ostertagia ODR values and herd type

Variable stability of chromosomes containing amplified alpha-satellite sequences in human mesenchymal tumours

Alpha-satellite sequences are found in the centromeric region of all human chromosomes and have been implicated in centromeric function. We describe the structure and behaviour of chromosomes containing amplified human alphoid DNA from chromosome 12, in an osteosarcoma cell line (OSA) and an atypical lipomatous tumour (ALT). In OSA, the amplified material was detected in one large marker chromosome, whereas in ALT amplified sequences were observed in chromosomes of variable number and appearance. The marker in OSA was mitotically stable, but those in ALT exhibited a high degree of mitotic instability, forming bridges at anaphase and chromatin strings between interphase nuclei. The amplified alpha-satellite arrays reacted positively with human anti-centromeric antiserum and anti-centromere protein B antibodies in both tumours. Centromere protein C, previously shown to be present only in functional kinetochores, was invariably detected at the constriction of the marker in OSA, while one-fifth of markers in ALT appeared to exhibit additional centromere protein C-positive regions outside the primary constriction, indicating that the observed chromosomal instability in ALT might, at least in part, be a consequence of the occasional formation of more than one functional kinetochore. In OSA the alphoid DNA was coamplified with unique sequences from central 12q and the amplified material was C-band negative but in ALT amplified material from central 12q as well as sequences from proximal 12p were detected, resulting in C-band-positive areas. A propensity for additional kinetochore formation might thus be associated with the coamplification of alphoid DNA and pericentromeric sequences from chromosome 12

Den sociala kreatören

Den sociala omgivningen spelar en viktig roll för designerns kreativa förmåga. Framförallt har omgivningen en viktig inverkan för designerns emotionella tillstånd som i sin tur påverkar humöret och kreativiteten. Undersökningen visar också att inspiration oftast hämtas från arbetsgruppen snarare än den privata omgivningen, ett mönster som förstärks med erfarenhet och ålder

Hibernomas are Characterized by Homozygous Deletions in the Multiple Endocrine Neoplasia Type I Region : Metaphase Fluorescence in Situ Hybridization Reveals Complex Rearrangements Not Detected by Conventional Cytogenetics

Hibernomas are benign tumors of brown fat, frequently characterized by aberrations of chromosome band 11q13. In this study, the chromosome 11 changes in five hibernomas were analyzed in detail by metaphase fluorescence in situ hybridization. In all cases, complex rearrangements leading to loss of chromosome 11 material were found. Deletions were present not only in those chromosomes that were shown to be rearranged by G-banding, but in four cases also in the ostensibly normal homologues, resulting in homozygous loss of several loci. Among these, the gene for multiple endocrine neoplasia type I (MEN1) was most frequently deleted. In addition to the MEN1 deletions, heterozygous loss of a second region, approximately 3 Mb distal to MEN1, was found in all five cases, adding to previous evidence for a second tumor suppressor locus in 11q13

Locus-specific multifluor FISH analysis allows physical characterization of complex chromosome abnormalities in neoplasia

Novel techniques in molecular cytogenetics have radically improved the ability to characterize genetic changes in neoplastic cells. In parallel, a rapid development in high-throughput genomics has resulted in detailed physical maps of the human genome. Combining these two fields, we have developed a method for the simultaneous visualization of several physically defined segments along a chromosome. Seven YAC clones and one subtelomeric cosmid clone from chromosome 12 were labeled with unique combinations of four fluors and hybridized to metaphase chromosomes from neoplastic cells. In a uterine leiomyoma and a myxoid liposarcoma with translocations 12;14 and 12;16, the breakpoints in chromosome 12 could be localized to the HMGIC and CHOP regions, respectively. In the other tumors, more complex aberrations were visualized, including two inversions in 12q with a common breakpoint between MDM2 and D12S332 in a pleomorphic adenoma, amplification of MDM2 and CDK4 in ring chromosomes from a malignant fibrous histiocytoma, and amplification of KRAS2 together with other unbalanced rearrangements in two pancreatic adenocarcinomas. Combinatorially labeled single-copy probes may thus simultaneously provide physical localization of breakpoints and an overview of complex structural rearrangements