Accelerated Growth Rate Induced by Neonatal High-Protein Milk Formula Is Not Supported by Increased Tissue Protein Synthesis in Low-Birth-Weight Piglets

Table 5

Fractional rates (𝐾_𝑠, %/d) of protein synthesis, protein synthesis efficiency (𝐾_RNA), ribosomal capacity (𝐶_𝑆) and protein contents (g/100 g tissue) measured in various tissues of piglets fed NP, HP, and HPA diets at d7 and d28.

	d7					d28					Age effect
	NP	HP	HPA	SEM	P	NP	HP	HPA	SEM	P
𝐾𝑠, %/d
Proximal jejunum mucosa	55.5	58.9	57.6	3.11	Ns	60.9^a	50.6^b	56.1^ab	1.71	<0.01	ns
Distal ileum mucosa	58.5^a	64.2^b	54.5^a	2.64	<0.05	53.3	53.5	48.2	2.13	ns	<0.01
Liver	67.5^a	82.9^b	75.1^ab	4.27	0.06	58.7	53.2	52.4	2.51	ns	<0.001
Semitendinosus muscle	18.6	19.7	20.7	1.06	Ns	11.8^a	10.6^ab	9.8^b	0.89	<0.1	<0.001
Carcass	16.2	17.1	18.2	0.91	Ns	14.4^a	12.5^b	11.9^b	0.34	<0.01	<0.001
𝐾RNA, g/g/d
Proximal jejunum mucosa	13.5	14.3	14.2	0.67	Ns	14.7	13.3	14.4	0.44	ns	ns
Distal ileum mucosa	12.0^a	13.3^b	12.4^ab	0.46	0.07	12.0^a	12.4^a	10.7^b	0.39	0.06	0.07
Liver	13.6^a	18.3^b	16.3^ab	0.76	<0.01	12.9	12.7	13.7	0.90	ns	<0.01
Semitendinosus muscle	10.8	10.9	11.6	0.79	Ns	11.8	10.6	9.8	0.86	ns	ns
Carcass	7.5	7.9	8.3	0.58	Ns	8.6	8.6	8.3	0.35	ns	ns
𝐶𝑠, mg RNA/g protein
Proximal jejunum mucosa	41.4	41.2	40.6	167	Ns	41.4	38.0	39.2	1.22	ns	ns
Distal ileum mucosa	48.8	48.8	44.0	1.97	Ns	44.3	43.0	45.5	2.13	ns	0.09
Liver	49.8	45.3	46.5	2.34	ns	45.6^a	42.4^a	38.6^b	1.60	<0.05	<0.01
Semitendinosus muscle	17.4	18.5	17.8	0.94	Ns	10.4	9.61	9.3	0.44	ns	<0.001
Carcass	21.9	21.6	22.6	1.38	Ns	16.9^a	14.6^b	14.4^b	0.54	<0.01	<0.001
Protein content, g/100 g tissue
Proximal jejunum mucosa	11.3	10.2	10.2	0.44	Ns	11.2	12.0	12.7	0.36	ns	<0.05
Distal ileum mucosa	9.0	8.9	8.7	0.49	Ns	8.8	9.4	8.9	0.40	ns	ns
Liver	12.1	11.7	11.9	0.62	Ns	11.9^a	14.2^b	13.7^b	0.42	<0.05	<0.01
Semitendinosus muscle	7.7	7.9	7.1	0.53	Ns	8.1	9.7	8.5	1.15	ns	ns
Carcass	8.3	8.5	8.7	0.62	Ns	11.4	12.7	11.6	0.59	ns	<0.001

Values are least square means and pooled SEM calculated in pigs slaughtered at d7 and d28, 𝑛=6/group. P (effect of formula) and age effects are presented. Differences were considered significant when 𝑃<0.05 but trends are presented when 0.1 < 𝑃<0.05. Means with a different superscript letter differ at 𝑃<0.05.