1. Department of Animal Production, Faculty of Agriculture, Ain Shams University, Cairo, Egypt
2. Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma del Estado de México, Toluca, Mexico
3. Unidad Académica de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Guerrero, Altamirano, Mexico
4. Department of Animal Sciences, School of Agriculture, Pwani University, Kilifi, Kenya