Table 2.

Faecal egg count reduction test in calves naturally infected with gastrointestinal nematodes in six Danish cattle farms. A total of 115 first-season grazers were sampled on the day of treatment (Day 0) and 14 days post-treatment (Day 14). The calves were treated with ivermectin (IVM, 0.2 mg kg⁻¹ body weight s.c.) or left untreated (CTL). Treatment efficacies were calculated including the variation of faecal egg counts (FEC) in treated and control groups (With CTL) or in treated groups only (No CTL). Total post-treatment FEC aggregation estimates (k) for each farm are shown according to the modified Bayescount.

	Farm #1 (Beef, conv.)		Farm #2 (Dairy, org.)		Farm #3 (Dairy, conv.)		Farm #4 (Dairy, org.)		Farm #5 (Beef, org.)		Farm #6 (Dairy, org.)
Group	IVM	CTL	IVM	CTL	IVM	CTL	IVM	CTL	IVM	CTL	IVM	CTL
n	10	10	10	10	10	10	10	9	10	10	7	9
FEC Day 0	333	325	76	69	173	209	354	351	55	39	31	77
FEC Day 14	46	311	14	55	15	286	51	562	4	98	4	126
k	0.7 (0.4–0.9)		0.7 (0.1–1.0)		0.3 (0.1–0.6)		0.3 (0.2–0.5)		1.0 (0.6–1.4)		0.2 (0.1–0.4)
With CTL	FECR%	[CI]	FECR%	[CI]	FECR%	[CI]	FECR%	[CI]	FECR%	[CI]	FECR%	[CI]
WAAVPa	85I	[67–95]	75R	[27–92]	95I	[56–99]	91I	[74–97]	96E	[92–99]	97I	[65–99]
Bayescountb	87R	[80–94]	78R	[61–92]	93I	[70–99]	91I	[73–99]	96E	[92–99]	90I	[52–99]
No CTL	FECR%	[CI]	FECR%	[CI]	FECR%	[CI]	FECR%	[CI]	FECR%	[CI]	FECR%	[CI]
WAAVPa	86R	[66–94]	82R	[47–94]	92I	[30–99]	86R	[67–94]	94I	[87–97]	83I	[−50–98]
Bayescountb	87R	[81–93]	83R	[72–92]	90I	[62–98]	81R	[50–94]	92I	[84–98]	81I	[25–99]
eggCountsc	84R	[55–94]	80R	[50–91]	86I	[21–98]	83R	[47–94]	93I	[82–97]	83I	[22–97]

FEC = arithmetic mean faecal egg count; k = total post-treatment FEC aggregation estimate; FECR% = FEC reduction percentage; CI = 95% confidence interval.

^EEfficacious; ^RReduced efficacy; ^IInconclusive; conv. = conventional; org. = organic.

^aColes et al. (1992).

^bModified Bayescount (paired model with pooled between-animal and within-animal pre-treatment k).

^ceggCounts unpaired model (Torgerson et al., 2014).