The effect of using fennel powder in starter diets on performance, immunity system and biometric parameters of Holstein calves

In order to investigate the effect of adding Fennel powder (Foeniculum vulgare) in starter diet on performance, immunity system and biometric parameters of Holstein calves, 30 Holstein calves (15 males and 15 females) with birth weight of 40±0.5 kg were used in a completely randomized design. Experimental diets were: 1. starter without Fennel powder (control), 2. starter containing 0.4% Fennel powder and 3) starter with 0.8% of the Fennel powder. Average dry matter intake of calves increased by adding Fennel powder (P<0.05). Average daily gain of calves was highest with 0.4% of the Fennel powder (P<0.05). The average of weaning age and milk intake were lower in calves fed with fennel powder than control group (P<0.05). Effect of experimental diets on average fecal consistency in the period before weaning, after weaning and the total period were significant (P<0.05) only for two weeks after weaning. Blood eosinophil of calves were affected by the experimental diets (P<0.05). Thus, adding 0.4% Fennel powder in starter diet improves performance of Holstein dairy calves and reduces weaning age and eosinophils.