Sheep nemabiome diversity and its response to anthelmintic treatment in Swedish sheep herds

Parasites & Vectors

Table 2 Output from MCMCglmm testing of the impact of each of the three anthelmintic drug treatments (IVM = ivermectin, ABZ = albendazole, LEV = levamisole) on species richness and inverse Simpson’s diversity index (see also Fig. 4g–l) for farms sampled before and after anthelmintic treatment

Pre- vs. post-treatment	Anthelmintics	Posterior mean	Lower 95% CI	Upper 95% CI	Effective sample size	pMCMC¹
Species richness	IVM	− 0.6567	− 1.1476	− 0.1682	9914	0.0128*	Fig. 4g
Species richness	ABZ	− 0.98885	− 2.00249	− 0.08799	9488	0.043*	Fig. 4h
Species richness	LEV	0.2294	− 1.7207	2.1984	10000	0.7696	Fig. 4i
Inv Simpson's index	IVM	− 0.20087	− 0.48078	0.07807	10000	0.165	Fig. 4j
Inv Simpson's index	ABZ	− 0.25936	− 0.63469	0.08315	10000	0.145	Fig. 4k
Inv Simpson's index	LEV	0.3575	− 0.3554	1.1646	9623	0.289	Fig. 4l

¹Statistically significant fixed effects are marked with * (P < 0.05)
Prior settings: R (V = 2, nu = 0.2); G (V = 2, nu = 0.02)
Run settings: burn-in = 50,000; iterations = 100,000; thinning interval = 10
As an example, untreated sheep were infected with on average 0.66 fewer species compared to IVM treated sheep. No such effect was found in species richness for LEV, nor for any of the inverse Simpsons’ indices

ISSN: 1756-3305