Abstract
Aim/Background: Calcium is an essential mineral in poultry nutrition, crucial for skeletal development and eggshell quality. Marine shell extraction is labor-intensive and costly, so alternative calcium sources are necessary to reduce feed costs and preserve aquatic ecosystems. This study assesses the efficacy of Figuil limestone, shellfish, and quail eggshells as dietary calcium sources, primarily focusing on improving animal welfare.
Materials and Methods: Advanced analytical techniques, including X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDX), used to conduct a comprehensive assessment of Figuil limestone, shellfish, and quail eggshells. A total of 195 (21-day-old) Cobb500 chicks with comparable live weights were divided into 15 batches, each containing 13 mixed-gender chicks housed within low-meshed cages at a density rate set at 13 chicks/m². Five experimental diets were formulated, substituting shellfish meal with limestone powder at levels set at 0%, 25%, 50%, 75%, and 100% within a basal diet containing 20.14 % crude protein and 3069.50 kcal/kg metabolizable energy. Each diet was randomly assigned across three batches utilizing a completely randomized design where five treatments were repeated three times.
Results: Results indicate that Figuil limestone and quail eggshells are predominantly composed of calcite calcium, while shellfish primarily contain aragonite calcium. The calcium oxide (CaO) content was determined to be 50% in Figuil limestone, 42% in shellfish, and 26% in quail eggshells, with varying concentrations of magnesium (Mg), aluminum (Al), silicon (Si), and iron (Fe). Substituting shellfish meal with limestone powder notably influenced broiler feed consumption at six weeks of age, positively affecting live weight and average weekly weight gain. Treatment T4 (100% limestone) notably demonstrated promising outcomes, with significant differences (P ≤ 0.05) detected in feed consumption (FC), weight gain (WG), and feed conversion ratio (FCR) among the treatment groups.
Conclusion: Findings advocate for Figuil limestone powder as a sustainable and ethically sourced alternative to shellfish meal in broiler diets, capable of complete replacement up to 100%. This study highlights Figuil limestone's potential as a viable calcium source in animal feed formulations, offering environmentally friendly options for poultry nutrition while promoting animal welfare and delivering economic benefits to both developed and developing regions.

Key words: Alternative Calcium Sources; Animal Welfare; Figuil Limestone; Poultry Nutrition; Quail Eggshell Meal; Shellfish Meal; Sustainable Feed.