Table 3.

Microbial counts (log₁₀ cfu/g) in dry diets and in the dietary treatments collected from the mixing tanks and from the feed troughs in the pig pens^1,2

	Meal			Pellet				P-value
Form Delivery	Dry3	Mixing tank4	Trough5	Dry3	Mixing tank4	Trough5	SEM	Sampling location × feed form	Sampling location	Feed form
LAB	3.30b	6.77c	8.45d	2.29a	6.92c	8.31d	0.219	0.03	0.001	0.07
Enterobacteriaceae	5.24b,c	5.09b	6.09b,c	3.26a	5.15b,c	6.18c	0.276	0.001	0.001	0.01
Yeast	3.92b	3.64a,b	5.20c	3.12a	3.63a,b	5.35c	0.178	0.01	0.001	0.07
Mold	3.75	4.17	4.42	3.00	4.01	4.32	0.213	0.14	0.001	0.03

¹ Escherichia coli counts were omitted from this analysis due to normality issues with the data. Therefore, a logistic procedure was used to calculate the likelihood of presence or absence of E. coli in the mixing tank or dry feed compared to in the trough and these data are presented in the text.

²Values are the mean of data from samples taken on days 1, 27, and 57 of batch 1 and on the same days during batch 2, i.e., from 6 time points.

³Dry: represents dry feed samples collected from the storage bins used for preparing liquid feed and bagged diets used for feeding dry and wet/dry feed.

⁴Mixing tank: represents samples of liquid feed collected at the end of the agitation process.

⁵Trough: represents samples taken from liquid-fed troughs only, collected approximately three hours after feed-out.

^a,b,c,dWithin each row, values that do not share a common superscript are significantly different (P < 0.05).