Lysolecithin is an emulsifier that increases the digestion and absorption of fat and may result in increased energy availability and improved animal performance. The objective of this study was to evaluate the effects of the inclusion of lysolecithin in the milk replacer (24% CP, 19% Fat) and its influence on calves performance. Thirty-two newborn and colostrum-fed calves were blocked according to sex, date and weight of birth and distributed in 2 treatments: 1) Control: milk replacer; 2) Lysolecithin: milk replacer supplemented with lysolecithin (Lysoforte, 4 g/d). All calves were bucket fed 6 L/d of milk replacer diluted to 14% solids and had free access to water and concentrated. Body weight was measured every week, growth parameters were measured biweekly and feed intake and fecal score were registered daily. Data were analyazed as repeated measures using PROC Mixed of SAS. Even though the inclusion of lysolecithin had no effect on concentrate intake, supplemented calves presented higher ADG and feed efficiency (FE), resulting in a tendency for higher final body weight. However, body measurements were not affected by lysolecithin supplementation. Lysolecithin supplementation in the milk replacer decreased average fecal score, suggesting lower incidence of diarrhea. All parameters were affected by age, with increasing values for concentrate DMI, ADG and FE and fecal scores. Fecal scores were affected by the interaction of supplementation and age, with increasing differences between groups as calves aged. These results indicate that the emulsifier increases weight gain and efficiency of nutrients utilization without affecting feed intake. Table 1 (Abstr. M151). Performance of calves supplemented or not with lysolecithin

Item	Treatment		SEM	P-value1
Control	Lysolecithin	T	A	T × A
Concentrate DMI, g/d	264.95	285.95	28.42	0.59	<0.01	0.32
ADG, kg	0.280	0.406	0.03	0.01	<0.01	0.58
FE	0.22	0.31	0.02	0.01	0.01	0.52
Initial BW, kg	35.95	35.67	1.48	0.68	—	—
Final BW, kg (d 56)	52.68	57.07	2.37	0.07	—	—
Heart girth, cm	80.72	81.50	0.67	0.42	<0.01	0.66
Hip width, cm	20.81	20.91	0.26	0.77	<0.01	0.29
Wither height, cm	80.71	81.38	0.54	0.39	<0.01	0.17
Fecal score	1.53	0.78	0.07	<0.01	<0.01	<0.01

¹T = treatment effect; A = age effect; T×A = treatment vs age effect.