Effects of organic zinc and phytase supplementation in a maize–soybean meal diet on the performance and tissue zinc content of broiler chicks

Abstract

1. The purpose of this study was to investigate the effects of Bioplex Zn (a chelated zinc proteinate) and phytase supplementation in a maize-soybean meal diet on the performance and tissue zinc (Zn) content of broiler chicks. Treatment structure consisted of a 2 x 6 factorial arrangement with two inclusions of phytase (0 or 500 PU/kg) and 6 of Bioplex Zn providing 0, 2, 4, 8, 16 and 32 mg Zn/kg diet. A total of 864 chicks were randomly assigned to each of 12 dietary treatments with 6 replicate cages of 12 chicks. 2. Dietary inclusion of phytase increased feed intake, weight gain, plasma Zn content, tibia Zn content, tibia and ash weight. 3. Dietary supplementation of Bioplex Zn linearly increased feed intake, weight gain, gain to feed ratio, plasma Zn concentration, liver Zn concentration, tibia Zn content, tibia and ash weight. 4. An interactive effect of phytase and Bioplex Zn on feed intake, weight gain, tibia Zn concentration and tibia ash weight was found. 5. One slope, straight broken-line analysis of weight gain regressed on the supplemental Zn level provided as Bioplex Zn indicated that 12 mg/kg supplemental Zn without phytase and 7.4 mg/kg supplemental Zn with phytase were required for the optimal weight gain of chicks.

Zinc availability and digestive zinc solubility in piglets and broilers fed diets varying in their phytate contents, phytase activity and supplemented zinc source

“…These results are consistent with Ao et al (2007). According to Jondreville et al (2007), the respective dietary content of 50 and 59 mg Zn/kg (maize-soybean meal-based diet; 33 mg/kg Zn as native Zn) maximized broiler plasma and bone Zn concentration.…”

“…Dietary Zn contents slightly below 40 mg Zn/kg may therefore be sufficient for optimal growth over a limited time period of 21 days. In contrary, Ao et al (2007) observed improved growth performance when supplementing to broilers a maize-soybean meal diet with 500 FTU/kg phytase and/or 2 to 12 mg/kg Zn. However, it must be noted that the unsupplemented broilers had lower growth rates (29 g/day) than in this study.…”

“…Mohanna and Nys, 1999a;Revy et al, 2004) as well as other institutes (Ao et al, 2007). The experimental diets were formulated to provide minimal native Zn and maximal supplemental Zn while keeping animals below homeostatic Zn regulation capacity.…”

Using Exogenous Enzymes to Increase the Nutritional Value of Soybean Meal in Poultry Diet

“…The negative effect of phytate on mineral digestibility is ameliorated by dietary supplementation with microbial phytase. Microbial phytase supplementation in corn-soybean meal-based diets improved Ca availability and Zn utilization in poultry (Sebastian et al, 1996a,b;Ao et al 2007) and increased the apparent absorption of Mg, Zn, Cu and Fe in pigs (Adeola, 1995). Phytase supplementation also increased the ileal digestibility of crude protein, and most amino acids in both poultry and swine (Sebastian et al, 1997;Yi et al, 1996;Mroz et al, 1994).…”

The Use of Organic Zinc in Poultry Nutrition: Review

“…Nitekim, broylerlerde optimal büyüme oranı 25 mg/kg Zn içeren fitazlı ve fitazsız rasyona sırasıyla 7,4 ve 12 mg/kg ZnPro ilavesiyle elde edilmiştir. 33 Aynı araştırmacı-lar tarafından yapılan başka bir broyler çalışma-sında, başlangıç (0-21. günler) ve büyütme (22-42. günler) döneminde kontrol grubuna mısır-soya küs-pesi içeren bazal rasyon, deneme gruplarına ise sı-rasıyla bazal rasyona ilave olarak 40 mg/kg Zn-sül-fat, 80 mg/kg Zn sülfat, 12 mg/kg organik çinko (Znproteinat) ve 24 mg/kg organik çinko içeren rasyon verilmiştir. Büyütme döneminde gruplar arasında performans bakımından önemli bir farklılığa rastlanmaz iken; başlangıç döneminde 24 mg/kg organik çinko verilen grubun canlı ağırlık kazancı diğer gruplardan önemli derecede yüksek bulunmuştur.…”