The editorial by Vastolo et al. discusses the potential of alternative and novel livestock feeds to reduce environmental impact. Livestock production systems contribute significantly to greenhouse gas (GHG) emissions, primarily from enteric fermentation. The use of alternative feeds and additives can improve digestibility, animal performance, and reduce emissions. The article reviews 17 research articles and 1 review on the use of alternative feeds in ruminants, pigs, and poultry. Key findings include: 1. **Ruminants and Pigs:** - Rice straw with a particle size of 4 mm improved nutrient disappearance and volatile fatty acid production. - Tannins reduced methane and gas production but decreased dry matter digestibility. - Quercetin reduced methane emissions in a dose-dependent manner. - Glycerine from biodiesel did not cause adverse effects on goats. - Oilseed cakes had varying effects on intake, performance, and carcass characteristics. - Novel proanthocyanidins from Anogeissus pendula leaves showed potential for improving feed conversion ratios. 2. **Poultry:** - Saccharomyces cerevisiae and Lactobacillus acidophilus, with or without a prebiotic, effectively replaced zinc bacitracin. - Cowpea seeds and microencapsulated Lactobacillus salivarius improved broiler performance. - Pu-erh tea pomace reduced blood cholesterol levels by improving gut microbiota composition. - Litsaea cubeba extract improved amino acid content and meat quality. - Lysozyme supplementation improved intestinal morphology and immune efficiency in laying hens. - Spirulina, zinc-enriched yeast, and parsley minimized heat stress in broilers. - Moringa peregrina seed meal did not negatively affect performance or meat quality. The conclusion emphasizes that alternative feeds and additives can reduce environmental impact without adverse effects on animal performance, but further research is needed to optimize their use.The editorial by Vastolo et al. discusses the potential of alternative and novel livestock feeds to reduce environmental impact. Livestock production systems contribute significantly to greenhouse gas (GHG) emissions, primarily from enteric fermentation. The use of alternative feeds and additives can improve digestibility, animal performance, and reduce emissions. The article reviews 17 research articles and 1 review on the use of alternative feeds in ruminants, pigs, and poultry. Key findings include: 1. **Ruminants and Pigs:** - Rice straw with a particle size of 4 mm improved nutrient disappearance and volatile fatty acid production. - Tannins reduced methane and gas production but decreased dry matter digestibility. - Quercetin reduced methane emissions in a dose-dependent manner. - Glycerine from biodiesel did not cause adverse effects on goats. - Oilseed cakes had varying effects on intake, performance, and carcass characteristics. - Novel proanthocyanidins from Anogeissus pendula leaves showed potential for improving feed conversion ratios. 2. **Poultry:** - Saccharomyces cerevisiae and Lactobacillus acidophilus, with or without a prebiotic, effectively replaced zinc bacitracin. - Cowpea seeds and microencapsulated Lactobacillus salivarius improved broiler performance. - Pu-erh tea pomace reduced blood cholesterol levels by improving gut microbiota composition. - Litsaea cubeba extract improved amino acid content and meat quality. - Lysozyme supplementation improved intestinal morphology and immune efficiency in laying hens. - Spirulina, zinc-enriched yeast, and parsley minimized heat stress in broilers. - Moringa peregrina seed meal did not negatively affect performance or meat quality. The conclusion emphasizes that alternative feeds and additives can reduce environmental impact without adverse effects on animal performance, but further research is needed to optimize their use.