Growth Performance and Tibia Mineralization of Broiler Chickens Supplemented with a Liquid Extract of Humic Substances

Abstract

The objective of the study was to evaluate the productive, carcass, and tibia mineralization responses in broiler chickens supplemented with a liquid extract of humic substances (HS) in the drinking water. Chicks were housed in holding cages from 8-42 days of age and were randomly assigned to one of five increasing HS levels in the drinking water (0, 161, 322, 483, and 644 µg/L). At 21 and 42 days, to obtain carcass and tibia measurements half of the broilers were slaughtered. ANOVA and linear regression were used to analyze the data. The HS chemical composition and flat structures were estimated. At 21 days, increasing levels of HS in the drinking water resulted in a cubic response on breast weight (p<0.05), tibia ashes percentage (p<0.05) and tibia Ca percentage, as well as a linear increasing response (p<0.05) on P percentage. HS elicited a quadratic response on the tibia DM percentage (p<0.05), Ca content (p<0.01), and P content (p<0.05) at 42 days.The optimal HS supplementation level to achieve the highest tibia DM percentage, Ca and P content were 345.00, 322.46, and 347.75 µg/L, respectively. Increasing HS levels also resulted in a cubic response in tibia Ca (p<0.05) and P percentage (p<0.01). In conclusions, HS supplementation in drinking water improved bone mineralization in broiler chickens at 21 and 42 days of age.

The addition of humic substances extracted from vermicompost enhances the growth performance and the antioxidant status of weaning pigs

“…(33) In HS-fed broiler chickens, increased ash, Ca and P content in tibia bone have been reported. (27) In the present study, metatarsal weight and ash content were similar among treatments at seven days postweaning. This could have partially been due to the fact that broiler chickens had been added with HS for longer periods of time, with a range between 21 and 36 days.…”

“…HS are thought to be the most complex natural ligands, with a high potential to form chelates with various ions, which has been linked to improved mineral utilization in plants and animals. (9,10,27) Increased ash and Ca content in tibia bone in HS-fed broilers, (16)(17)(18) as well as, increased percentage, thickness, and hardness of eggshells in HS-supplemented laying hens and pheasants have been reported. (19)(20)(21) Improved femur mineralization and increased milk Ca and Fe content have also been reported in HS-added rabbits (22) and cows.…”

“…This could have partially been due to the fact that broiler chickens had been added with HS for longer periods of time, with a range between 21 and 36 days. (27) The determination of antioxidant capacity by the DPPH technique allows the activity of specific compounds or extracts to be evaluated using the free radical DPPH in anhydrous methanol solution. (30,31) This free radical is susceptible to react with antioxidant compounds through a process characterized by the yielding of an hydrogen atom provided by the antioxidant agent.…”

“…The concentrations of HA (47.1 %), FA (29.6 %) and ashes (23.2 %), as well as the functional groups, elemental analysis, crystal types, chemical properties and the flat structures of HS with aromaticity from the vermicompost were previously published. (26,27) In brief, sheep manure was pre-decomposed for two weeks before being inoculated with red Californian earthworm and the vermicompost was harvested three months later. Prior to extraction, the vermicompost was dried at room temperature and passed through a metal mesh to homogenize the particle size.…”