The current experiment was conducted to evaluate the effects of feeding dried sweet orange peel (SOP) and lemon grass leaves (LGL) as feed additives on broiler growth performance, serum metabolites, and antioxidant status. A total of 192-day-old (Ross 308) broiler chickens were distributed randomly into 4 dietary treatments with 4 replicates per each treatment. The dietary treatments included a control diet without any feed additive (T1), a diet containing 0.8 % SOP (T2), a diet containing 0.8 % LGL (T3), and a diet containing combination of 0.4 % SOP + 0.4 % LGL (T4) was fed during the growth period from 22 to 42 days. Feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), carcass traits, serum components, and antioxidant status were measured. At the end of the experimental period, the results indicated that supplementation of SOP and LGL alone or in combination did not significantly (P > 0.05) affect BWG, FI, FCR, and carcass characteristics in broiler chickens. Serum total protein was increased significantly (P < 0.05) in T3 and T4 compared to the other treatments. Also, serum globulin increased significantly (P < 0.05) in the treated groups. Serum glucose, low density lipoprotein, triglyceride, and very low density lipoprotein decreased significantly (P < 0.05) in the treatment groups, while cholesterol and high-density lipoprotein decreased in T2 compared to the other groups. Significantly (P < 0.05) higher total antioxidant status was observed in T2 compared to the other treatments. In conclusion, these results indicate that SOP, LGL, and their combination may positively modify some serum components and the antioxidant status without any beneficial effect on growth performance and carcass traits in broiler 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.

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.

No abstract