Fennel (Foeniculum vulgare) is an ancient medicinal plant and seasonal herb that belongs to the Apiaceae (Umbelliferae) family. Fennel originated from the southern Mediterranean region as an aromatic herb and through naturalization and cultivation it grows wild throughout the Northern, Eastern, and Western hemispheres, specifically in Asia, North America, and Europe. Fennel has been extensively used in traditional medicine for a wide range of ailments. It is cultivated in the Mediterranean region because of its flavor, and it is used in traditional medicine and as a spice. Specific applications studied in poultry include:
Heat stress: Fennel may be a useful feed supplement to provide laying hens during hot weather, to alleviate the adverse effects of heat stress pertaining to egg quality. A study conducted in 2015 on 120, 40-week-old White Leghorn laying hens showed that adding 10 to 20 g/kg of fennel to the birds' feed for 30 days was beneficial. In addition, the study showed that independent of heat stress, the hens' consumption of fennel significantly reduced the amount of cholesterol and triglycerides in the egg yolk.
Anticoccidial: Studies show it may be of benefit against coccidiosis in chickens.