Dietary iron and broiler performance

Abstract

1. An experiment was conducted with female broilers from 1 to 39 d of age in which the effects of increasing amounts of extra dietary ferrous sulphate on growth performance, some haematological measurements and Fe, Zn and Cu status were studied. A conventional maize-soyabean diet (107 mg Fe/kg) was supplemented with 0, 20, 60, 180, 540 and 1620 mg Fe to provide 6 treatments. 2. Weight gain responses rose to a plateau between 20 and 60 mg added Fe/kg diet, but further additions of Fe increasingly depressed growth. 3. In this study the apparent Fe requirement was 100 mg/kg diet (80 mg from dietary components and 20 mg Fe from supplement). 4. The efficiency of food utilisation decreased linearly, while the proportion of chicks affected by leg weakness increased. 5. In blood, the haemoglobin concentration increased slightly with extra dietary Fe. 6. The iron content of the liver increased with higher dietary Fe supplementation. Furthermore, increased liver Fe content was associated with a higher Zn content in the liver. 7. This study indicated that a maize-soyabean diet containing about 30% more Fe than has generally been accepted to be adequate for healthy broilers was still marginal in Fe concentration.

Cottonseed Oil in Diets for Broilers in the Pre-Starter and Starter Phases

“…In this study, the apparent iron requirement was 100 mg/kg diet (80 mg from dietary components and 20 mg from supplemented iron). These results were similar to those found in the present study, indicating that excessive amounts of iron in broiler diets may compromise their performance [ 21 ].…”

Determination of dietary iron requirements by full expression of iron-containing cytochrome c oxidase in the heart of broilers from 22 to 42 d of age

“…Moreover, in these earlier studies, growth performance, Hb concentration and haematocrit were often used to assess Fe requirements in chicks fed purified or semi-purified diets, and the Fe requirements for broilers during days 1-21 (or days 1-29) were defined as 45-85 mg/kg (4,5,6,(33)(34)(35) . On the other hand, Vahl et al (36) and Ma et al (18) reported that the Fe requirements in broilers fed a practical maize-soyabean-meal diet were 100 and 118 mg/kg for the optimum growth from 1 to 21 or 1 to 39 d of age, respectively. The Fe requirements in broilers fed the practical diets are higher than requirements for those fed purified or semi-purified diets, which might be due to the adverse effect of phytate and fibre on Fe absorption (7)(8)(9) .…”

“…Nevertheless, the growth performance is always influenced by the type of diets or growth phase and, thus, it might not be a good index for assessing Fe requirements for broilers. Besides, many studies have demonstrated that haematological indices, such as Hb concentration or haematocrit, could reflect the Fe nutritional status or be a sensitive criteria for estimating the Fe requirement of broilers fed purified or semi-purified diets (4,36) . Ma et al (37) found that blood Hb concentration and haematocrit of chicks fed a casein-dextrose diet increased linearly as dietary Fe level increased; Davis et al (4) reported that the Fe requirements of chicks fed a soyabean protein-casein-gelatin diet were 78 and 77 mg/kg for Hb concentration and haematocrit, respectively.…”

Effects of oxidative stress induced by high dosage of dietary iron ingested on intestinal damage and caecal microbiota in Chinese Yellow broilers

“…We increased the iron added up to 1,200 and 2,400 mg/kg in the two trial groups during 22–42 days in the subsequent trial and also found no adverse effect on growth performance, even some characteristics of oxidative stress disappeared on the 42 days old (data not shown). However, other study determined the higher Fe concentration (1,620 mg/kg) in diet which produced adverse effects including less body weight and feed conversion rate, and more leg disorders in broilers (Vahl & Van’ T Klooster, ).…”