[Advances in the research of application of maggot therapy in chronic wounds].

Maggot therapy is a kind of biological therapy that uses maggot to eat and remove the necrotic tissue of wounds, while it has no adverse effect on living tissue with blood supply. Besides, maggot therapy can promote wound healing through various mechanisms, which has been used for debridement and treatment of wounds as early as hundreds of years ago. With the discovery and application of antibiotics, maggot therapy faded out of the medical field once. However, with the abuse of antibiotics and increasing drug resistance of bacteria in recent years, maggot therapy attracts widespread attention of clinicians again. This article reviews the advances in the application of maggot therapy in chronic wounds.

Changes in composition a metabolism of caecal microbiota in rats fed diets supplemented with copper-loaded chitosan nanoparticles.

The study was conducted to investigate the effect of copper-loaded chitosan nanoparticles on the composition and metabolism of the caecal microbiota in rats. Forty male Sprague-Dawley (SD) rats (average body weight of 82 ± 5 g) were randomly assigned to five groups (n = 8). The dietary treatments were: (i) basal diet, (ii) basal diet + 80 mg/kg BW CuSO(4), (iii) basal diet + 80 mg/kg BW chitosan (CS-I), (iv) basal diet + 80 mg/kg BW copper-loaded chitosan nanoparticles (CSN-I) and (v) basal diet + 160 mg/kg BW copper-loaded chitosan nanoparticles (CSN-II). The trial lasted 21 days. The results showed that compared with control, Average day gain (ADG) of group CSN-I and CSN-II increased (p < 0.05). No significant difference was found in CuSO(4) or CS-I-treated groups (p > 0.05). There were no effects of these treatments on average day feed intake (ADFI) of rats (p > 0.05). The counts of Bifidobacteria and Lactobacillus in group CSN-II were higher than those of the control group (p < 0.05), while the counts of total aerobes, total anaerobes, Salmonella, Clostridium and coliform were lower than those of the control (p < 0.05). The activity of ß-glucuronidase in group CSN-I or CSN-II was significantly depressed (p < 0.05), while the activities of α-galactosidase and ß-galactosidase were enhanced significantly (p < 0.05). The pH of the caecum digesta and the concentration of propionate and butyrate in group CSN-I and CSN-II were higher than those of the control group (p < 0.05). No significant difference was found in these parameters in CuSO(4) or CS-I-treated groups (p > 0.05). The results indicate that the microbiota and environment of caecum are beneficially changed by the administration of copper-loaded CSN.

Effects of beta-glucanase and xylanase supplementation on gastrointestinal digestive enzyme activities of weaned piglets fed a barley-based diet.

The effects of supplementing a barley-based diet for weaned piglets withexogenous beta-glucanase and xylanase on gastrointestinal digestiveenzyme activities were investigated. Thirty-six cross-bred weaned pigletswere randomly assigned to two groups with three pens based on sexand mass. Each group was fed on the diet based on barley with or withoutadded beta-glucanase and xylanase (0.15%) for a 4-week period. Theresults showed that enzyme supplementation improved growth performanceof piglets significantly (p < 0.05), but had no effect (p = 0.091)on average daily feed intake. The results also showed that supplementationof beta-glucanase and xylanase had no effect on pepsin activity in gastriccontents but slightly decreased (p = 0.092) the pepsin activity ingastric mucosa. Meanwhile, no effect of enzyme supplementation ontrypsin activity in duodenal contents was observed. However, the activitiesof amylase and lipase in duodenal contents were significantly(p < 0.05) decreased, whereas the activities of maltase, sucrase andgamma-glutamyl transpeptidase (gamma-GT) in jejunal and ileal mucosa wereenhanced significantly (p < 0.05). The improvement of disaccharidaseand gamma-GT activity may be attributed to the positive impacts of exogenousenzymes on digestion and absorption of the nutrients. In conclusion,the current results indicated that supplementation with enzymes in barley-based diets could improve the growth performance of piglets,decrease the activities of amylase and lipase in duodenal contents andincrease the activities of disaccharidase and gamma-GT in jejunal and ilealmucosa.

Effect of cadmium in feed on organs and meat colour of growing pigs.

One hundred and ninety-two barrows (Duroc x Landrace x Yorkshire, initial weight 27.7 kg) were used to investigate the effects of cadmium in feed on the function of selected organs and meat colour of growing pigs. The pigs were randomly allocated into four different treatments. Each treatment included three replications with 16 pigs per replicate. The animals were fed corn-soybean basal diet and supplemented with 0, 0.5, 5.0, 10.0 mg/kg cadmium (as CdCl(2)), respectively. The feeding trial ended when the average body weight of the pigs reach 90 kg. The results showed that, compared with controls, addition of 10 mg/kg cadmium to the diet resulted in significant elevations of relative weight of liver and spleen by 18.3% (p<0.05) and 19.7% (p<0.05) respectively, and of serum glutamic-pyruvic transaminase (GPT) and glutamic-oxaloacetic transaminase (GOT) activities by 17.8% (p<0.05) and 27.4% (p<0.05) respectively; and significant decreases of Na(+)/K(+)-ATPase activity in the liver by 24.6% (p<0.05), the redness of longissimus dorsi by 26.6% (p<0.05) and 24.9% (p<0.05) at 0.75 h and 16 h post mortem, respectively, and of the myoglobin content of longissimus dorsi by 19.4% (p<0.05). No changes were found in these indices above when the pigs were fed the diet supplied with 0.5 or 5 mg/kg cadmium (p>0.05), nor in renal functions among cadmium-treatment treatments (p>0.05) as indicated is the activities of urinary N-acetyl-beta-D-glucosaminidase (NAG) and alkaline phosphatase (ALP) and the content of urinary protein. The study indicated the adverse effects of 10 mg/kg cadmium in feed on liver functions and meat colour of growing pigs.

Effects of dietary arsenic levels on serum parameters and trace mineral retentions in growing and finishing pigs.

This experiment was conducted to investigate the effect of dietary arsenic (As) levels on growth performance, serum biochemistry, and the retention of iron, copper, and zinc in tissues of growing and finishing pigs. Ninety-six crossbred pigs were randomly allotted to four dietary treatments. The corn-soybean basal diets were supplemented with 0, 10, 20, and 30 mg As/kg. Arsenic trioxide was used as the arsenic source. The feeding experiment lasted for 78 d. The results showed that the high arsenic diet decreased average daily gain (ADG) (p<0.05) and increased feed gain ratio (F/G) (p<0.05). Arsenic intake significantly increased (p<0.05) serum gamma-gultamyltransferase (GGT), glutamic-pyruvic transaminase (GPT), and alkaline phosphatase (ALP) activities, and decreased (p<0.05) total protein, urea nitrogen, creatinine, and triglycerides. Glutamic-oxalacetic transaminase (GOT) activity, albumin, and cholesterol were not affected (p>0.05). Arsenic feeding elevated (p<0.05) liver and kidney copper concentration, but reduced (p<0.05) copper concentration in heart, bile, and lymphaden of intestine mesentery. There were increases in iron levels in liver, bile, spleen, thymus, and pancreas in pigs fed the high As diets (p<0.05), but iron contents in kidney, heart, and serum were decreased by the arsenic treatment (p<0.05). Zinc concentrations were increased (p<0.05) in liver, kidney, and thymus of pigs with arsenic treatment, but decreased (p<0.05) in bile and lymphaden of intestine mesentery. This study suggested that high dietary As levels could alter serum biochemical parameters and the retention of copper, iron, and zinc in the viscera of growing and finishing pigs.

Effects on growth and cadmium residues from feeding cadmium-added diets with and without montmorillonite nanocomposite to growing pigs.

One hundred and ninety-two crossbred pigs (barrows, Duroc x Landrace x Yorkshine, initial weight 27.6 kg) were used to evaluate the effects of montmorillonite nanocomposite (MNC) on cadmium (Cd) retention in tissues of growing pigs. The animals were randomly assigned to 2 supplementations of Cd (0 or 10 mg/kg) and 2 levels of MNC (0 or 0.5%) in a 2x2 factorial arrangement. Each group was fed corn-soybean basal diets and consisted of 3 replications of 16 pigs. The feeding experiment lasted 83 d. Pig growth performances decreased significantly by addition of 10 mg Cd/kg (p<0.05) and improved with supplementation of MNC (p<0.05). Addition of MNC with Cd decreased Cd retentions in muscle, liver, kidney, spleen, thymus and lymphaden of pigs (p<0.05). MNC also decreased tissue Cd residues of pigs fed the diet without added Cd (p>0.05). There were decreased iron levels and increased copper levels in serum and liver of 10 mg Cd/kg treatment (p<0.05). Zinc content in serum and liver was not affected by the addition of Cd (p>0.05). Serum and liver iron, copper and zinc concentrations of pigs fed MNC without added Cd were unaffected by MNC (p>0.05).

[Hemodynamic effects of a water soluble extract of Liriope spicata Lour on anesthetized cats].

The effects of water soluble extract of Liriope spicata on acute hemodynamics were studied in anesthetized cats. The results showed that LV dp/dt max was increased by 87%, whereas t-dp/dt max was shortened by 28% after administration of WSEL (1.75 g/kg, iv). At the same time CO, CI, SI, and SVWI were increased by 146, 151, 153, and 194%, respectively. HR was declined slightly. SVR was reduced by about 48%. WSEL (0.7 g/kg, iv) induced an increase of 38% in LV dp/dt max, 44% in CO, 50% in SI and a decrease of 20% in t-dp/dt max and 20% in SVR. Preliminary results indicated that WSEL increased ventricular contractile force and might increase cardiac pump function.