Effects of copper-loaded chitosan nanoparticles on intestinal microflora and morphology in weaned piglets.

The objective of the present study was to investigate the effects of dietary supplementation with copper-loaded chitosan nanoparticles (CNP-Cu) on growth performance, intestinal microflora, and morphology in weaned piglets. A number of 90 weaned piglets (Duroc × Landrace × Yorkshire), weaned at 21 days with body weight of 7.2 ± 0.81 kg, were randomly divided into three groups by weight and sex, each treatment including three replicates of ten pigs. The piglets were fed the same basal diet supplemented with 0 (the control group), 100 mg/kg CNP-Cu, and 100 mg/kg chlortetracycline (the positive group). The results showed that 100 mg/kg CNP-Cu significantly increased average daily gain and feed intake and decreased feed/gain ratio and diarrhea rate (P < 0.05). Compared with the control group, the amount of Escherichia coli in duodenum, jejunal, and caecum were significantly decreased by 100 mg/kg CNP-Cu; the number of lactobacillus in jejunal and caecum were increased (P < 0.05), and the amount of bifidobacterium in duodenum and caecum were also increased (P < 0.05). Moreover, the villous height of duodenum, jejunum, and ileum mucosa was significantly increased (P < 0.05), and the crypt depth was significantly decreased (P < 0.05). The results indicated that CNP-Cu is beneficial to growth and intestinal microflora and morphology and could be a potential substitution of chlortetracycline in diets of weaned piglets.

Effects of chromium-loaded chitosan nanoparticles on growth, blood metabolites, immune traits and tissue chromium in finishing pigs.

Effects of chromium-loaded chitosan nanoparticles (Cr-CNP) on growth performance, blood metabolites, immune traits, and tissue chromium in finishing pigs were investigated. A total of 160 crossbred barrows (66.06 ± 1.01 kg initial weight) were randomly divided into four groups, each group with four pens, ten pigs per pen. Pigs were fed on the same basal diet supplemented with 0 (the control), 100, 200, and 400 µg/kg Cr from Cr-CNP. All pigs were given free access to feed and water. Eight pigs from each treatment were selected to collect blood and tissue samples after 35 days on trial for analysis of blood metabolites and immune traits and tissue chromium. The results of feeding trial showed that there were no significant difference in growth performance between control and Cr-CNP-treated groups. The supplementation of Cr-CNP decreased serum glucose (P < 0.001) in a linear and quadratic manner. Serum immunoglobulins A and M were linearly increased in Cr-CNP-treated groups (P < 0.001), and serum complement 4 in Cr-CNP-treated groups was also linearly increased (P < 0.05). Cr-CNP supplementation linearly increased the chromium content in the blood, longissimus muscle, heart, liver, kidney, and pancreas (P < 0.001). These results suggested that dietary supplementation of Cr as Cr-CNP affects serum glucose, influences immune status, and increases the tissue chromium content of blood, muscle, and selected organs in finishing pigs.

Efficacy of dietary chromium (III) supplementation on tissue chromium deposition in finishing pigs.

The study was conducted to evaluate the efficacy of different forms of trivalent chromium (Cr) supplementation on tissue chromium deposition in finishing pigs. A total of 96 pigs with an initial average body mass 65.57±1.05 kg were blocked by body mass and randomly assigned to four treatments with three replicates. Pigs were offered one of four diets including a control diet or the control diet supplemented with 200 µg/kg chromium from either chromium chloride (CrCl(3)), chromium picolinate (CrPic) or chromium nanocomposite (CrNano) for 40 days. During the trial, all pigs were given free access to feed and water. After feeding trial, eight pigs from each treatment were slaughtered for samples collection. The results showed that supplemental CrNano increased Cr content in blood, longissimus muscle, heart, liver, kidney, jejunum, and ileum (P<0.05). Supplemental Cr from three sources increased Cr excretion from all feces (P<0.05). Urinary Cr excretion was increased by CrNano or CrPic supplementation significantly. These results suggested that chromium nanocomposite exhibited more effective on tissue Cr deposition in pigs, which indicated higher absorption compared with CrCl(3) and CrPic.