No abstract

The effects of dietary Spirulina platensis on chicken macrophage phagocytic function and nitrite production were examined. Day old broiler (meat-type) chicks were randomly assigned to various pens of electrically heated wire batteries. Dietary treatment groups included a basal diet with no dietary Spirulina added, and three additional groups with 0.5, 1.0 and 2.0% dietary Spirulina. Feed and water were provided for ad libitum consumption from one day of age. Sephadex-elicited macrophages were harvested at 14, 35 and 42 days of age. Phagocytosis assay was performed by co-incubating sheep red blood cells (SRBC) with the adherent macrophage monolayers. For nitrite quantification, macrophage cultures from various dietary treatment groups were stimulated in the presence or absence of 1 microg/mL of Escherichia coli lipopolysaccharide. These culture supernatant fractions were then tested for nitrite levels using the Greiss reagent technique. All Spirulina dietary group macrophages exhibited an enhanced phagocytic activity in terms of overall phagocytic percentage (range = 28 to 39% versus 24 to 25% in the basal group) and the average number of SRBC per phagocytic macrophage (range = 2.2 to 3.6 versus 1.8 to 2.5 in the basal group). This increase was linear with each incremental increase of dietary Spirulina. While LPS-induced nitrite levels in macrophages from basal diet group ranged from 60 to 278 microM over the three developmental ages, these levels in all Spirulina dietary groups were significantly higher (0.5% group range = 198 to 457 microM; 1.0% group range = 161 to 359 microM and 2.0% group range = 204 to 420 microM. These data clearly show that Spirulina platensis feeding upregulates macrophage phagocytic as well as metabolic pathways leading to increased nitric oxide synthase activity. These findings therefore imply that Spirulina platensis may enhance the functions of mononuclear phagocytic system thereby increasing the disease resistance potential in chickens.

The present study aimed at evaluating the effects of probiotics, prebiotics and their combination on intestinal histological changes in broiler chickens challenged with Clostridium perfringens. Two hundred and forty newly hatched male broilers (Ross 308) were equally distributed into six treatments: negative control group: unsupplemented unchallenged birds; positive control group: unsupplemented challenged birds; neoxyval-fed group: 0.5 g/kg diet (antibiotic) challenged birds; GalliPro-fed group: 0.6 g/kg diet (probiotic), challenged birds; TechnoMos-fed group: 0.75 g/kg diet (prebiotic), challenged birds; and synbiotic-fed group: birds challenged by C. Perfringens (4 x 10 8 CFU /mL). At 35 days old, samples from the ileum and jejunum were collected for histological measurements (height, width and villus surface area), and histopathological changes were assessed. The results showed that the length and surface area of villi in the ileum and jejunum were lower in the positive control, whereas length and surface area of villi in the ileum and jejunum of all feed additive treatments were higher, compared with the positive control and antibiotics. Necrotic enteritis (NE) development was evident in the positive control group. Signs of necrosis of the mucosal membranes, haemorrhage and fibrosis with depletions of gut associated lymph follicle (GALF) in submucosal layer were very clear. Pathological changes improved in all feed additives, except for the antibiotics. These results indicated that alternatives to antibiotics could be used to improve the length and surface area of a villus and the health of the animal by suppressing C. perfringens.

No abstract

The anticoccidial influences of various amounts of Cinnamomum verum powder were compared with that of salinomycin as standard synthetic anticoccidial drug on the anticoccidial indicators and production performance in broilers experimentally exposed to coccidiosis. Broiler chicks at 1 d of age ( n = 150) were arbitrarily distributed into 6 groups. Birds from groups 1–3 were received the starter and finisher diets plus 2, 4, and 6 g of cinnamon/kg of the diet, respectively. Birds from group 4 were fed the starter and finisher diets plus 66 mg of salinomycin, group 5 constituted the positive control ( PC ), with the coccidial challenge, and group 6 constituted the negative control ( NC ), without the coccidial infection, which were both maintained on diets without any cinnamon. The results showed that BW gain, feed conversion ratio, and production efficiency factor declined considerably ( P < 0.05) in the PC compared with the NC. At seventh day postinfection ( DPI ), the lesion score was significantly ( P < 0.05) lower in the ceca of salinomycin-treated birds than the PC. The anticoccidial index was moderate in the chickens treated with salinomycin and 6 g cinnamon at 7 DPI compared with those in the PC group. In addition, cinnamon- or salinomycin-treated birds exhibited lower oocyst values and higher oocyst reduction rate than those in the PC. We concluded that C. verum at level 6 g cinnamon/kg diet moderately reduced coccidiosis and attempted to improved BW, feed conversion ratio, and production efficiency at 7 DPI compared with the infected groups.