Table 5. Muscle fiber characteristics in the longissimus thoracis muscle at 24 h post-mortem in piglets of different birth weight groups

Parameters	Treatment groups				p-value
	NBW-C	NBW-HF	LBW-HF	LBW-HFHD
n	5	6	7	5
Total muscle fibers in loin muscle area	79,152±20,129	128,875±19,125	87,888±12,993	95,396±20,129	0.1073
Type I muscle fibers (%)	10.32±2.10	9.27±2.00	9.66±1.36	6.05±2.10	0.2642
Type IIA muscle fibers (%)	16.40±3.10	19.04±2.95	17.00±2.00	18.03±3.10	0.8436
Type IIB muscle fibers (%)	73.28±3.41	71.69±3.24	73.34±2.20	75.92±3.41	0.6970
Mean muscle fibers diameter (μm)	42.57±2.80b	39.833±2.66b	46.757±1.81ab	51.032±2.80a	0.0057
Type I muscle fibers diameter (μm)	38.86±2.67ab	37.36±2.54b	43.21±1.73ab	44.86±2.67a	0.0401
Type IIA muscle fibers diameter (μm)	38.91±3.06	36.30±2.90	39.38±1.97	40.85±3.06	0.5379
Type IIB muscle fibers diameter (μm)	49.94±3.19	45.85±3.03	51.09±2.06	53.25±3.19	0.1723

Data represents mean±SE.
Different letters in the same row are significantly different in different animal groups at the 0.05 level of probability (p<0.05).
NBW, normal birth weight; C, control (chow diet); HF, high fat diet; LBW, low birth weight; HFHD, high fat dairy source.