Once small always small? To what extent morphometric characteristics and post-weaning starter regime affect pig lifetime growth performance

Table 2 Total number of pigs pre- and post-weaning per birth weight class. Within batch birth weight classes were created retrospectively using percentiles (25%) resulting in 4 different groups. Class 1 represents the lightest piglets and class 4 the heaviest. At weaning pens were randomly allocated to one of the starter regimes: control (CTRL) vs. nutrient enriched starter regime (HIGH)

Birth weight class	1		2		3		4		Total		Significance¹
Starter regime	CTRL	HIGH	CTRL	HIGH	CTRL	HIGH	CTRL	HIGH	CTRL	HIGH
Number of pigs²
Day 0	374		371		372		370		1487		1.000
Day 28	148	147	202^a	150^b	192	169	137^b	217^a	679	683	< 0.001
Day 48	146	139	199^a	143^b	190	167	137^b	215^a	672	664	< 0.001
Day 61	146	138	198^a	143^b	190	167	137^b	215^a	671	663	< 0.001
Day 97	142	133	189^a	128^b	176^a	146^b	115^b	191^a	564	557	< 0.001
Day 75	15^a	5^b	19	6	12	10	12	20	58	41	0.164
Day 99³	127	128	170^a	122^b	164^a	136^b	103^b	171^a	515	498	< 0.001

^a,bAbsolute values within birth weight class with different superscripts differ significantly (P < 0.05) between starter regimes
¹A chi square test was used to test the overall difference between the different birth weight classes x starter regime (entire row, excluding total)
²Pigs were followed from birth (d 0), weaning (d 27.7, SD = 1.07), grower (d 61.5, SD = 1.17), to finisher (d 96.9, SD = 6.63). Two hundred and six pigs were sold as growers (32.6 kg, SD = 2.86) at an age of d 75 (d 74.8, SD = 1.94) of which 99 were weighed and the rest (n = 107) no additional weights were taken
³Only those pigs that reached finisher age on site (d 98.8, SD = 0.938)

ISSN: 2055-5660