الفهرس 
1. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The present study aimed to evaluate in vitro and in vivo dietary supplementation with
different levels of natural or nano zeolite form on rumen fermentation parameters and
nutrient digestibility. In the in vitro experiment, basal substrate (50:50) was incubated
without additives (control) and with natural zeolite (10, 20, 30 g/kg DM) or nano zeolite
(0.2, 0.3, 0.4, 0.5, 1.0 g/kg DM) for 24 h to assess their effect on ruminal fermentation, feed
degradability, and gas and methane production. The gas production (GP) was recorded at 3,
6, 9, 12, and 24 h of incubation using a semi-automatic system. In the in vivo experiment,
the effects of obtained in vitro effective doses on nutrient digestibility using thirty Barki
goats (BW; 26 ± 0.9 kg). Goats were allotted into three dietary treatments (n =10/treatment)
as: control (basal diet supplementation), Natural Zeolite (20 g/kg DM) and Nano Zeolite
(0.40 g/kg DM daily oral doses). The results revealed that nano zeolite supplemented at (0.5
g/ kg DM) had the highest GP (P=0.0005) compared to the control group. The in vitro CH4
production was decreased (P<0.001) by 49 % with the supplementation of natural zeolite
(20 g/kg DM), and by 15 % with nano zeolite (0.4 g/kg DM). Nano zeolite at 0.4 g/kg DM
was the most efficient treatment to decrease (P<0.007) ruminal ammonia nitrogen
concentration and tended to increase (P=0.069) the truly degraded organic matter. Low dose
of nano zeolite (from 0.2 to 0.4 g/kg DM) and medium dose of natural zeolite (20 g/kg DM)
tended to reduce (P<0.06) acetate proportion and acetate to propionate ratio, while enhanced
propionate (P=0.005) production. The nutrient digestibility was similar (P>0.05) among
treatments. The in vivo assay was implemented to assess the effects of the inclusion of
different zeolite forms (nature and micro-sized) in milk yield, composition, milk fatty acids
profile, productive and reproductive performance, some blood biochemical constituents, and
the rumen fermentation in goats. Thirty-nine female Balady goats (BW: 26.08±0.9 kg, aging
1-3 years) were randomly distributed to one of three diets. Goats in the control group were
fed a basal diet (50:50) without additives while the two experimental diets were supplied
with 20g/kg DM natural zeolite and 0.4g/kg micro-sized zeolite respectively. Diet
supplemented with micro-sized zeolite (0.4 g/kg DM) increased (P>0.05) milk production,
fat, protein, lactose and solid not fat yield compare to control group. Also, the
concentrations of blood serum total proteins, albumin, globulin, calcium, and total
antioxidant capacity were increased (P> 0.05). While milk protein, lactose, solid not fat
proportions, and somatic cell count were decreased (P> 0.05) with no effect on milk fat
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percentage. Both natural and micro-sized zeolite increased (P> 0.05) ruminal pH three hours
after feeding and decreased (P> 0.05) the ruminal ammonia concentration compared to the
control. While micro-sized zeolite supplementation to the diet increased total VFA and
butyric concentration. In conclusion, micro-sized zeolite can improve goat performance and
serum protein and antioxidant status. Meanwhile does not appear to result in harmful effects
on reproductive parameters and growth performance of goat kids. The present study
demonstrates that zeolite supplementation play an important role in modifying rumen fermentation.