Table 7. Pre and post-weaning mean values of the fecal score, respiratory score, days with a respiratory score above 4, days with fever, days with diarrhea, days with severe diarrhea of control heifers (CON) and heifers supplemented with a blend of essential oils (BEO) in milk replacer during pre-weaning.

	Treatment		SEM	P–value3
Item	CON1 (n = 15)	BEO2 (n = 14)		T	W	T x W
Pre-weaning (4 to 60 d)
Fecal score4	0.54	0.45	0.04	0.04	<0.001	0.18
Respiratory score4	0.79	0.69	0.02	0.22	<0.001	0.02
Days with respiratory score > 45	0.00	0.14	0.05	0.44	–	–
Days with fever	0.94	0.98	0.20	0.66	–	–
Days with diarrhea	7.87	5.79	0.71	0.24	–	–
Days with severe diarrhea	3.13	1.93	0.37	0.12	–	–
Post-weaning (61 to 90 d)
Fecal score	0.04	0.04	0.009	0.43	0.68	0.95
Respiratory score	1.10	1.03	0.05	0.59	<0.001	0.74
Days with respiratory score > 4	0.00	0.00	–	–	–	–
Days with fever	0.52	0.90	0.23	0.21	–	–

¹ CON = control

²BEO = 1 g/calf/d blend of essential oil.

³ T = treatment effect; W = week effect, T x W = treatment by week interactions.

⁴ Scores were adapted to follow the University of Wisconsin calf health scoring chart [2].

⁵There were no days with respiratory score > 4 during the post-weaning period.