D Shafieipour fard1; Somayeh Salari; Mohsen Sari; Saman Abdanan Mehdizadeh; Mehdi Zarei
Volume 18, Issue 3 , October 2016, , Pages 539-552
Abstract
This experiment was conducted to evaluate the effect of different lipid sources and organic zinc supplementation on performance, egg bacterial activity and ovary morphology of laying hens for 10 weeks. with 288 sixty weeks old birds by employing a completely randomized design with factorial arrangement ...
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This experiment was conducted to evaluate the effect of different lipid sources and organic zinc supplementation on performance, egg bacterial activity and ovary morphology of laying hens for 10 weeks. with 288 sixty weeks old birds by employing a completely randomized design with factorial arrangement of 3×4 with 12 treatments, 4 replicates and 6 hens each. The factors of interest were 4% lipid from different sources (soybean oil, fish oil and tallow) and various levels of zinc (40, 100, 200 and 300 mg/kg of diet). In all three lipid sources, significant reduction (P<0.05) was observed in feed intake when the level of zinc supplementation increased. Haugh unit was significantly (P<0.05) increased in diets containing different lipid sources as the level of zinc supplementation increased. The highest Haugh unit value was observed at the level of 100 mg/kg of zinc supplementation with soybean oil and fish oil. Increasing levels of zinc supplementation significantly (P<0.05) improved eggshell thichness, eggshell strength and eggshell percentage. The number of large white follicles linearly increased in diets containing tallow, when the level of zinc supplementation increased. The egg yolk microbial load was significantly (P<0.05) decreased by different lipid sources as the level of zinc supplementation increased. According to the results, it seems that the addition of zinc to the diets containing different lipid sources could not affected performance parameters but decreased egg yolk microbial load.