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.

The study was designed to evaluate the effects of different levels of clove (Syzygium aromaticum) powder in the diet on growth performance and histological changes of the livers and intestines of broiler chickens at 21 and 35 days old. Three hundred and thirty-six one-day-old Ross (308) broilers were allocated to eight treatments, namely: NC: negative control and unvaccinated; PC: positive control and vaccinated; and treatments T1, T2, T3, T4, T5 and T6 supplemented with different levels of clove powder (10, 20, 30, 40, 50 and 60 g clove powder/kg of diet, respectively) and all vaccinated. At 21 and 35 days old, eight birds/treatment were weighed, and samples from the livers and intestines were collected to evaluate morphological and histological changes. The results showed that higher levels of clove powder (T3 to T6) resulted in a gradual decrease in the live body weight of the birds at 21 and 35 days old. Relative liver weight increased in T5 and T6 at 35 days, but not at 21 days. A shorter small intestine was recorded in birds that received 50 and 60 g (T5 and T6) clove powder, while the proportional length of small intestinal parts did not show differences among treatments at 21 and 35 days old. The supplementation in the T3 toT6 groups resulted in a gradual decrease in intestinal weight at 21 days, but was not evident at 35 days. Villus height, villus surface area and villus crypt depth showed a gradual decrease from T1 to T6 at 35 days old. Also, gradual loss was recorded of the intestinal epithelium structure by necrotic enteritis on the wall of villi with an increased level of clove powder (< T2). These results indicated that 10 g clove powder per kg diet could be used to improve the growth rate without affecting the health of the liver and intestines of broilers.

A total of 192 one-day-old Ross 308 broiler chicks were assigned to 4 treatments with 8 replicate cages of 6 chicks (3♀ and 3♂) per cage according to a completely randomized block design. The dietary treatments were a basal diet (control) and a control diet supplemented with 1,000, 3,000, and 5,000 mg/kg Rumex nervosus leaves meal ( RN ). Gallic acid and some volatile compounds were detected in the RN extract. On day 10 of age, BW was improved ( P = 0.016) with supplemental RN (1,000–5,000 mg/kg). On day 14 of age, dietary application of RN up to 3,000 mg/kg increased BWG ( P = 0.003) compared with control, while a 1,000 mg/kg RN had the best feed conversion ratio ( P = 0.016). On day 10 of age, samples were taken on a single female bird per replicate. The addition of RN (1,000–5,000 mg/kg) increased ( P < 0.001) serum albumin and triiodothyronine levels and maximized the relative weight of breast meat ( P = 0.003). Feeding a diet with 1,000 mg/kg RN resulted in greater duodenal villus height ( P < 0.001) than control and the diet with 5,000 mg/kg RN. Broilers fed diet supplemented with 1,000 mg/kg RN had the best duodenal villus surface area ( P < 0.001). Feeding a diet with 1,000 mg/kg RN decreased ( P < 0.001) cecal Escherichia coli count compared with control and the diet with 5,000 mg/kg RN. Salmonella spp. count tended to increase with 5,000 mg/kg RN leaves meal ( P = 0.069, linear P = 0.026). In conclusion, R. nervosus leaves meal could be considered as a phytogenic feed additive in broiler diets up to a 1,000-mg/kg inclusion rate because of its combined positive effects on BWG, feed conversion ratio, villus height, villus surface area, serum albumin and triiodothyronine hormone, and cecal E. coli during the starter period (day 10–14 of age). Further study is required to elucidate its molecular mechanism.

Previous studies have shown positive outcomes associated with the incorporation of cloves into broiler chicken diets. This study aimed to evaluate carcass characteristics, meat quality, and sensory attributes of broiler chickens fed diets supplemented with different clove seed levels. A total of 240 day-old Ross 308 broiler chicks were fed 1 of seven dietary treatments. The control group diet contained 0% clove seeds, whereas the treatment group diets contained up to 6% clove seeds. The chickens' final BW was significantly different between the treatments, which decreased linearly with increasing levels of clove seed inclusion. Broiler chickens fortified with clove seeds did not significantly affect the chickens' carcass characteristics and body composition. However, an increment in weights of carcass components (liver, heart, and gizzard) was observed in low clove seed levels. In addition, water-holding capacity, cooking loss percentages, and tenderness of the meat were improved owing to clove seed inclusion (1 or 2%) compared with the control group. Further studies are warranted to optimize the outstanding use of cloves toward broiler chicken performance enhancement and to produce a high quality of meat.