. 2020 Aug 26;99(11):5214–5221. doi: 10.1016/j.psj.2020.08.018

Table 3.

The effects of access to a water pool on the development of preen gland weight (mean ± SE).

Age (wk)	Feeding system	Weight of PG (g)	Relative weight of PG (g.kg⁻¹)
0	—	0.11 ± 0.01	2.87 ± 0.13
1	WP	0.75 ± 0.05	3.88 ± 0.05^A
	LWP	0.66 ± 0.10	3.37 ± 0.06^B
2	WP	1.60 ± 0.50	3.80 ± 0.16^A
	LWP	1.59 ± 0.11	3.11 ± 0.01^B
3	WP	2.26 ± 0.11^A	2.40 ± 0.05^A
	LWP	2.11 ± 0.04^B	2.16 ± 0.04^B
4	WP	2.79 ± 0.50^A	2.31 ± 0.36^A
	LWP	2.39 ± 0.25^B	1.86 ± 0.18^B
5	WP	3.76 ± 0.47^A	2.02 ± 0.20^A
	LWP	2.65 ± 0.28^B	1.36 ± 0.14^B
6	WP	4.66 ± 0.29^A	1.95 ± 0.07^A
	LWP	2.98 ± 0.17^B	1.21 ± 0.17^B
SEM		0.058	0.022
P-value	Treatment	<0.001	<0.001
	Age	<0.001	<0.001
	Treatment∗Age	<0.001	0.003

Mean values with different superscript in column between WP and LWP are significant different (P < 0.05).

Abbreviations: LWP, lack of water pool; WP, providing with water pool.