Dictyocaulus sp.

Davidson, Rebecca K., Amundsen, Hanne, Lie, Nora Oftenes, Luyckx, Katrien, Robertson, Lucy J., Verocai, Guilherme G., Kutz, Susan J. & Ytrehus, BjØrnar, 2014, Sentinels in a climatic outpost: Endoparasites in the introduced muskox (Ovibos moschatus wardi) population of Dovrefjell, Norway, International Journal for Parasitology: Parasites and Wildlife 3 (2), pp. 154-160 : 157

3.4. Protostrongylid and Dictyocaulus sp. larvae

Protostrongylid DSL and Dictyocaulus sp. were detected in 82% and 78% of the faecal samples, respectively ( Table 3). Larval intensity in the positive animals ranged from 1 to 265 LPG for DSL (mean 34.4 and median 17.5) and from 0.4 to 760 LPG for Dictyocaulus sp. (mean 72.2 and median 24.5). Analysis of the results showed mean Dictyocaulus LPG in the dataset as a whole was significantly lower in August than in June (p = 0.021) whilst the opposite trend was seen for DSL, although the significance level was not reached (p = 0.097). The highest mean Dictyocaulus sp. LPG was recorded in yearlings. No significant differences were seen in the dataset as a whole for Dictyocaulus (p = 0.215, 2-tailed test) or DSL (p = 0.456, 2-tailed test) larval prevalence between the two sampling months but significant age related differences were seen.

Yearlings had significantly higher Dictyocaulus larval intensities than the other classes in June (p = 0.001). Calves and yearlings had significantly lower DSL larval intensities in June (p <0.001) and August (p = 0.003) than the other age classes tested in those periods.

Dictyocaulus larval prevalence in calves was higher in August than June although the significance level was not reached (p = 0.008, right tailed test; greater for August than June) however larval intensity was significantly higher in August than June (p = 0.040). Similarly DSL larval prevalence (p = 0.007, right tailed test) and intensity (p = 0.008) were significantly higher in August than June in the calf age group. No significant differences in Dictyocaulus or DSL larval prevalence and intensity were seen in yearlings. The age class representing 2–3 year old (young) animals were only sampled in June so further comparison was not possible and no significant differences in larval prevalence and intensity were seen in samples from the unknown age class group. Adults had significantly higher Dictyocaulus larval intensity in June compared to August (p <0.001), and larval prevalence was significantly higher in June than August (p = 0.017, left tailed test; greater for June than August). Adults also had higher DSL intensity in June compared to August (p = 0.052) although the prevalence level remained equally high in both periods as all adult samples tested positive for DSL larvae.

We obtained ITS-2 sequences (405 bp) of 2 DSL larvae from 2 different samples from unknown individuals from different locations. Both were identified as Muellerius capillaris (GenBank accession number: KJ534589–90), and shared 99–100% identity with M. capillaris ITS-2 sequences available in GenBank (AY679327,28,30).