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Historically, surveys of equine parasites either are not quantitative in regard to prevalence and intensities of cyathostome species, or if quantitative, are estimates based on the identification of a very small sample of the population. Commonly 100–200 worms are identified. In the current study cyathostomes from 10 ponies were counted and identified to species in subsets of approximately 200 worms each from 5% aliquots of the large intestine contents until all worms in the aliquot were examined. A mean of 10.9±4.3 species were identified by examining 200 cyathostomes from each animal. This number increased to 25.2±2.6 species when the 5% aliquots were totally examined, indicating that prevalence rates from species with low intensities are probably much greater than previous survey data indicate. A statistical model was used to determine how many worms need to be identified to give a 95% confidence level that all species present are identified. [Copyright &y& Elsevier]

Sedimentological colour data obtained from North Atlantic deep-sea sediment core NEAP15K provide a continuous climate record for the last 11500 yr with a mean sampling interval of <15 yr. Variations in sediment lightness, a proxy for changes in North Atlantic Deep Water (NADW) circulation, are characterized by high-frequency fluctuations with periodicities equivalent to 550 and 1000 yr, as well as a <1600-yr cyclicity comparable to that reported in other studies of Holocene climate. Cross-spectral analysis suggests that the 550- yr and 1000-yr cyclical variations in NADW circulation were coherent with fluctuations in atmospheric conditions over Greenland, where both these periodicities have been identified previously in the Holocene GISP2 d 18 O record (Stuiver et al., 1995). A similar statistical comparison provides evidence that high-frequency (550- yr) variability in NADW circulation patterns may have been linked to short-term variations in atmospheric 14 C values during the Holocene. In general, NADW production was lower and 14 C levels were higher when colder climatic conditions prevailed. These results imply that the pattern of NADW production has been a significant factor affecting centennial- to millennial-scale Holocene climate variability in the North Atlantic region. [ABSTRACT FROM AUTHOR]

Abstract: Salinity increase in the subtropical gyre system may have pre-conditioned the North Atlantic Ocean for a rapid return to stronger overturning circulation and high-latitude warming following meltwater events during the Last Glacial period. Here we investigate the Gulf Stream – subtropical gyre system properties over Dansgaard–Oeschger (DO) cycles 14 to 12, including Heinrich ice-rafting event 5. During the Holocene and Last Glacial Maximum a positive gradient in surface dwelling planktonic foraminifera δ18O (Globigerinoides ruber) can be observed between the Gulf Stream and subtropical gyre, due to decreasing temperature, increasing salinity, and a change from summer to year-round occurrence of G. ruber. We assess whether this gradient was a common feature during stadial-interstadial climate oscillations of Marine Isotope Stage 3, by comparing existing G. ruber δ18O from ODP Site 1060 (subtropical gyre location) and new data from ODP Site 1056 (Gulf Stream location) between 54 and 46 ka. Our results suggest that this gradient was largely absent during the period studied. During the major warm DO interstadials 14 and 12 we infer a more zonal and wider Gulf Stream, influencing both ODP Sites 1056 and 1060. A Gulf Stream presence during these major interstadials is also suggested by the large vertical δ18O gradient between shallow dwelling planktonic foraminifera species, especially G. ruber, and the deep dwelling species Globorotalia inflata at site 1056, which we associate with strong summer stratification and Gulf Stream presence. A major reduction in this vertical δ18O gradient from 51 ka until the end of Heinrich event 5 at 48.5 ka suggests site 1056 was situated within the subtropical gyre in this mainly cold period, from which we infer a migration of the Gulf Stream to a position nearer to the continental shelf, indicative of a narrower Gulf Stream with possibly reduced transport. [Copyright &y& Elsevier]

Abstract: Controlled trials with a common protocol were conducted in Idaho, Illinois and Tennessee to evaluate anthelmintic effectiveness of Quest® Gel (QG; 2% moxidectin) against lumenal parasites in horses. Candidate horses were required to have naturally acquired nematode infections, as confirmed by presence of strongylid eggs in feces. At each site, 24 equids were blocked on the basis of pretreatment strongyle fecal egg counts (EPG) and randomly assigned to treatments within blocks. Within each block of two animals, one received QG on Day 0 at a dosage of 0.4mg moxidectin/kg b.w. and one was an untreated control. Body weights measured the day before treatment served as the basis for calculating treatment doses. Horses assigned to treatment with QG received the prescribed dose administered orally with the commercially packaged Sure Dial™ syringe. Horses were necropsied 12–14 days after treatment, and lumenal parasites and digesta were harvested separately from each of five organs, including the stomach, small intestine, cecum, ventral colon and dorsal colon. Parasites from stomachs and small intestines were identified to genus, species and stage. Micro- (i.e., <1.5cm) and macroparasites (i.e., >1.5cm) in aliquots from the cecum, ventral colon and dorsal colon were examined in aliquots of approximately 200 parasites until at least 600 parasites had been identified to genus, species and stage or until all parasites in the 5% aliquot were examined, whichever occurred first. Data were combined across sites and analyzed by mixed model analysis of variance to assess the fixed effect of treatment and random effects of site and block within site. Because QG does not contain a cestocide, efficacy of QG against tapeworms was not significant (P >0.05). Based on geometric means, however, efficacy of QG was greater than 90% (P <0.05) against 38 species and developmental stages of cyathostomes, strongyles, bots, larval pinworms and ascarids encountered in at least 6 of 36 control horses in the combined data set. None of the horses treated with moxidectin exhibited evidence of adverse effects. Study results demonstrate QG, administered to horses with naturally acquired endoparasite infections at a dosage of 0.4mg moxidectin/kg b.w., was highly effective against a broad range of equine parasitic infections. [Copyright &y& Elsevier]