Study Of The Effect Of Oligochitosan On Growth And Development Of The Broilers

This research studied the effect of oligochitosan on the growth and development of the broilers by measuring the indices of the digestive tract and the digestive gland, immunal function, caecal microbial ecology, digestibility of the nutrition, distribution of mineral element in the organs and growth performance. The results showed as follows: when the basal diet was added 0, 5mg/kg, 25mg/kg and 125mg/kg oligochitosan respectively and the experiments were lasted 49 days in 125mg/kg oligochitosan group the relative weights of pancreas, duodenum, caecum, colon and rectum of the broilers were decreased 7.19%, 14.05%, 12.75% and 19.95% respectively compared with the control group (P<0.05), the macosa thickness of duodenum, jejunum and ileum deceased 35.34%, 18.18% and 27.91%respectively (P<0.05), the thickness of intestinal wall deceased 11.99%, 34.27% and 29.92%respectively (P<0.05), the villous height of jejunum and ileum of the broilers increased 8.09% and 36.66%compared with the control group(P<0.05), the cypt depth of duodenum, jejunum and ileum increased 18.11%, 37.14% and 23.56% respectively (P<0.05), the villous width decreased 23.54%, 61.97% and 8.31% (P<0.05), the density of ileum microvillus increased 4.50%compared with the control group (P<0.05), the relative weights of thymus and bursa.F. of the broilers increased 16.51% and 45.92%(P<0.05) and the serum antibody titres to the newcastle disease virus of the broilers increased 22.22% at seven weeks old, the result of the number of E.coli, bifidobacteria and lactobacilli of 49-day-old broilers showed that: oligochitosan decreased the number of E.coli, bifidobacteria and lactobacilli (P>0.05), the result of digestive experiment showed that: the N deposit rat of broilers increased 11.47% compared with the control group(P<0.01), but the digestibility of crude fat, crude fiber and ash of broilers were decreased 7.04% and 42.90%(P<0.01). The mineral element contents were measured.The result showed that: the contents of Ca,Mg,Mn,Zn and Fe in the liver of the broilers in each group were increased and they are highest in 125mg/kg oligochitosan group increasing 358.00%(P<0.01), 561.27%(P<0.01), 41.03%(P<0.01), 202.66%(P<0.05) and 73.57%(P<0.01), and the content of Mn in the musculus pectoralis major decreased 29.46%(P<0.05). The contents of Ca,Mg,Mn,Zn and Fe in the musculus pectoralis minor decreased with the increasing of oligochitosan in the diet. Oligochitosan increased the contents of Ca,Mg,Mn in the muscle of thighs. The contents of Ca and Mg in the 5mg/kg oligochitosan group and Mn in the 125mg/kg oligochitosan group were the highest increasing 44.24%(P<0.01), 53.06% and 20.67%(P<0.01) respecticvely(P<0.05). The result of growth performance showed that: 5mg/kg, 25mg/kg and 125mg/kg oligochitosan increased the body weight of the broilers in each group with the increasing of oligochitosan in the diet. The body weight of 49-day-old broilers increased 5.85%(P<0.05)and the feed/gain decreased 3.93%(P<0.05). When oligochitosan increased to 1000mg/kg the broilers's weight promoted 18.00%(P<0.05) and the feed/gain decreased 3.40%.