In order to study the effect of chitosan, pectin and vitamin C tools for removing heavy metals (HM's) from diets and as antioxidant and its effect on goats performance, experimental diets consisted of concentrate feed mixture (CFM) plus acacia forage irrigated with wastewater, were served as control (D1); D1 plus 5 gm /head/d chitosan (D2); D1 plus 20 gm/ head /d purified pectin (D3) and D1 plus 500 mg/head/d vitamin C (D4). Twenty lactating Zaraibi does in the 2nd and 3rd season of lactation with 34.5 kg in average body weights were used for feeding trial. They were randomly divided into four equal groups (5 does each). While twelve Zaraibi bucks 50.2 kg weight were used in four digestion trials. For rumen fermentation trials, three does fitted with permanent rumen fistula were used. Goats were offered acacia forage ad libitum twice a day at 8.00 and 16.00 plus restricted amount of CFM to cover 50% of protein requirements according to NRC (2007). Results showed that: 1- Acacia plant had lower pH than that of wastewater or soil; while all HM's in acacia were higher than that in wastewater or soil; 2- Digestibility coefficients, nutritive values and nitrogen utilization of goats fed diet supplemented with pectin or vitamin C had significantly highest (P<0.01) values, followed by diet supplemented with chitosan, while control diet was recorded the lowest values. 3- Ammonia-N concentration was decreased (P< 0.01) with chitosan, pectin or vitamin C supplementation; while VFA's concentration was increased; 4- Molar proportion of VFA's in rumen of goats showed that acetic acid concentration was higher in D3 and D4 than other diets, while propionic acid had the highest (P< 0.05) value with group supplemented with chitosan, and no significant difference among treatments was found respecting butyric acid concentration; 5- Pectin or vitamin C addition lead to an increase in ruminal bacteria numbers and their activities, not only that, but they had higher (P< 0.01) for microbial protein (MP) syntheses as well; 6- Milk production was significant increased with all supplemented groups and in the meantime does showed significantly better feed conversion compared with control one; 7- Serum glucose, cholesterol, urea, AST and ALT in blood were significantly (P<0.01) decreased by the supplementation of chitosan, pectin or vitamin C compared with control diet. While, serum total protein, albumin and globulin were significantly (P<0.05) increased; and 8- Heavy metals residues in the feces of chitosan, pectin or vitamin C groups was showed high values compared with the control group. But their residues in the blood serum and milk were fewer values compared with the control group. It could be concluded from this study that supplementation with chitosan, pectin or vitamin C could improve goats' performance and remove of HM's from blood and milk .However, the use of pectin or vitamin C could come in the first priority versus chitosan that come in the least priority.
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