Studies On The Source Of SDBC And Nutritional Physiological Functions Of Globin Peptides In Weanling Piglets

In order to identify the source of SDBC and study the Nutritional Physiological Functions of Globin peptides in weanling piglets, a PCR method was established to detect the source of SDBC.Then,one hundred and sixty 35 days old male"Landrace×Large" white pigs were randomly assigned to four groups: The control group, 0.5 %, 1.0 % and 2.0 % globin peptides group. Each group consisted of four replicates with 10 piglets per replicate. The growth performance, serum biochemical parameters and digestive tract index were measured.The results are as follows:1. The reported primers of bovine, porcine and chicken showed high specificity and accuration detected in PCR amplification. Amplified mitochondrion DNA fragment size of chicken, porcine and bovine in line with the expected fragments, the homology were 100%, 100% and 98% respectively. Sensitivity results showed that the detection limitation was 0.05 %.2. The effect of three adding levels of globin peptide to diet were investigated in weanling piglets.The result showed that additon of 0.5 % and 2.0 % globin peptides group had a significant effect on ADG in comparison to the control group (P<0.05), There were no significant difference on the ADFI and F/G among all groups (P>0.05). The diarrhea ratio of 0.5 % and 1.0 % globin peptides groups decreased significantly than that of other groups (P<0.05).The ADG of piglets were increased with the addition of globin peptides in the first two weeks, and 2.0 % globin peptide group was best. However, with the increase of piglet age, The ADG of 2.0 % globin peptide group was decreased and the diarrhea ratio was increased. In summary, 0.5 % globin peptide group had a best growth performance. The quadratic regression curve showed that the optimal adding dosage of globin peptide in early-weanling phase was 0.623 %.3. The concentration of serum TP, GLO, IgG (P<0.05) and ALT (P<0.01)in 0.5% globin peptide group were significantly higher than those in the control group. However, the concentration of BUN in 2.0% globin peptide group was significantly higher than that of 0.5 % globin peptide group (P<0.05).The results showed that the suitable addition of globin peptides to diet could improve the growth performance and immunity of piglets, while excessive globin peptides would have an adverse effect.4. After adding 0.5 % globin peptide to diet,the thymus and submandibular lymph node index,VH in duodenum,VCR in jejunum and Ileum were significant higher than those on the control,and a significant decline on CD of Ileum(P<0.05),the activity of AMS,TPS,Invertase in duodenum,TPS in jejunum,AMS in Ileum were also significant higher than the control group(P<0.05),but there was no significant effect on the activity of LPS in small intestine(P>0.05).The results showed that globin peptides have physical adjustment function,can promote digestive enzymes secretion,early development and self-repair capacity of small intestine.The results indicated that adding globin peptides to diet of early-weanling piglet could improve the growth performance of piglets, enhance immunity, and promote the early development of digestive tract.However, adding excessive globin peptides would not only increase cost but also affect the normal growth and development of piglets.Moreover, the appropriate addition of globin peptide was 0.5 %.