The aim of this study was to determine the effects of xylanase and flaxseed the performance of chickens, digesta viscosity, nutrient retention, fatty acid profile in muscle, tibia strength and interrelations of these factors in broiler chickens fed a wheat-based diet. Seven hundred and twenty one-day-old Ross 308 cockerels were assigned to four treatments according to the contents of flaxseed (0 and 80 g/kg) and xylanase (0 and 0.1 g/kg) in the diet. Xylanase significantly decreased the intake of feed (p < 0.001), decreased feed conversion (p < 0.001), and reduced mortality (p = 0.050). In addition, xylanase significantly increased the retention of all nutrients (p = 0.010 -<0.001) except crude fibre, the fat content in breast meat (p = 0.029) and liver (p = 0.019) and the concentration of polyunsaturated fatty acids (PUFAs) in meat (p = 0.002). Flaxseed supplementation did not influence performance but decreased the retention of dry matter (p = 0.016), crude protein (p = 0.012), organic matter (p = 0.016) and nitrogen-free extract (p = 0.008). Xylanase in combination with flaxseed increased the content of n-3 fatty acids in the breast meat (p = 0.006). The lowest n-6/n-3 ratio (p = 0.001) was detected in the flaxseed and flaxseed combined with xylanase groups. Significant interaction effects of flaxseed and xylanase on tibia strength (p = 0.030) and tibia ash content (p = 0.009) were detected. The administration of xylanase or flaxseed alone increased tibia strength. Compared with the control diet, the addition of flaxseed to the diet increased the digesta viscosity (p = 0.043) in the ileum, whereas the addition of xylanase decreased the level of this indicator. It can be concluded that xylanase is an enzyme suitable for increasing nutrient availability, and in the case of its addition to a flaxseed diet, it can reduce the antinutritional effect of flaxseed by reducing the viscosity of the digesta and increasing the content of health-promoting n-3 PUFAs.

• MeSH
• endo-1,4-beta-xylanasy * metabolismus   MeSH
• fyziologie výživy zvířat MeSH
• kostní denzita účinky léků   MeSH
• krmivo pro zvířata * analýza   MeSH
• kur domácí * MeSH
• len * chemie   MeSH
• polysacharidy * farmakologie   MeSH
• potravní doplňky * analýza   MeSH
• tibie účinky léků   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• endo-1,4-beta-xylanasy * MeSH
• polysacharidy * MeSH

The aim of the study is to determine the effect of hemp seed (HS) of the nonpsychotropic variety Futura and extruded flaxseed (EF) in the diet of cockerels on cockerel growth performance, breast muscle and liver α- and γ-tocopherol concentrations, breast muscle fatty acid concentrations and tibia strength. Five hundred and forty one-day-old male Ross 308 cockerels are equally allocated into six groups. Each group has three replicates of 30 cockerels in pens with litter. The formulated diets are isoenergetic (the metabolisable energy ranged from 12.4 to 12.8 MJ/kg) and isonitrogenic (the protein concentration ranged from 209.7 to 210.9 g/kg) and provided ad libitum. During the experiment, which lasts 35 days, the control group is fed a diet without EF or HS. Rapeseed oil was the lipid source in the control diet. The diet for the second group contains EF at 60 g/kg, the diet for the third group contains HS at 40 g/kg, and the diets for the fourth to sixth groups contain HS and EF at 30 and 60 g/kg, 40 and 60 g/kg and 50 and 60 g/kg, respectively. At the end of the experiment, 15 cockerels of average weight are slaughtered per group, and the breast muscle, liver and tibia bone are dissected for chemical analyses. The all dietary combination of HS and EF increases (p < 0.001) cockerel body weight (2375-2493 g) more than HS alone (2174 g) or EF alone (2254 g). A similar finding is observed for the diet composition and tocopherol content in the liver, but the doses of HS required to achieve this effect are higher (40 and 50 g/kg). The tocopherol content in the breast muscle is not influenced by the diet. The dietary combination of 60 g/kg EF and 40 g/kg HS results in the most promising findings of the experiment, since it leads to the lowest n-6/n-3 polyunsaturated fatty acids ratio (p < 0.001; 1.75). Incorporation of HS into the diet increases cockerel tibia strength (p < 0.001), which is of great practical importance due to the frequent occurrence of limb fractures. To conclude, the dietary supplementation with 40 g/kg HS and 60 g/kg EF improves cockerel performance, meat and bone quality and deposition of α-tocopherol in the liver.

• Klíčová slova
• breast muscle quality, broiler chickens, n-3 polyunsaturated fatty acid, tibia minerals, vitamin E,
• Publikační typ
• časopisecké články MeSH