The World Health Organisation has determined that as a result of improper antibiotic use, microorganisms become immune to certain antibiotics over time and are not effective in protecting human health. For this reason, the use of antibiotics in animal production is prohibited in European Union countries (Anadon, 2006). As a result, researchers began to search for growth factors that could be an alternative to antibiotics. In recent years, medicinal aromatic plants and their extracted essential oils have been used as an alternative to feed additives. Due to the safe and healthy consumption of vegetable oils by humans and animals (OJEU, 2003), importance has been given to their use in animal feeding and breeding all over the world and in Turkiye.
Ginger, which has been used medicinally in China and India for many years, is one of the plants used as an alternative to antibiotics. Ginger has various pharmacological properties, primary antimicrobial and anticancer (Da Silveira Vasconcelos et al., 2019). Used as a spice and flavouring, ginger has antioxidant and antihypercholesterolemic activity. In addition, ginger, which is rich in essential oils and minerals, can be used to increase productivity in livestock. The stimulating effect of the bioactive components of ginger on gastric secretion and enzymes positively affects feed efficiency and nutrient utilization (Ogbuewu and Mbajiongu, 2020). In addition, it positively affects lipid digestion and absorption by increasing the synthesis of bile acids in the liver and their excretion in bile (Prakash and Srinivasan, 2012).
It has been reported that ginger root powder affects feed consumption, milk production and milk quality without adversely affecting the health of cows (Al-dain and Jerjeis, 2015). The supplementation of the olebiotic flavour obtained from ginger to the calf starter does not affect the milk and feed consumption, body weight gain, feed conversion ratio, plasma glucose value, β-hydroxybutyrate, blood urea nitrogen and creatine values of the calves (Davarmensh et al., 2015). However, ginger supplemented with the diets of sheep significantly reduced the intake of dry matter, crude protein, ether extract and fibre (Muhammed et al., 2016). In addition, it has been reported that ginger supplemented with the diets of pregnant sheep can increase milk yield and components, red and white blood cells (Hendawy et al., 2019). Also, it has been reported by Ikyume et al. (2020) that ginger supplemented to sheep diets significantly increases daily body weight gain without affecting body weight, hay and concentrate feed consumption, and feed conversion ratio. However, they reported that while the total volatile fatty acids, propionate, acetate and butyrate values increased significantly, affected the rumen pH insignificantly and also did not affect the rumen bacteria, fungi and protozoa populations.
Studies with ginger liquid extract are limited. There is not much information about the effects on calves’ growth performance, feed utilization, intestinal bacterial flora, immune response and oxidative stress. Therefore, this study, it was aimed to test the hypothesis of whether ginger extract can be used in the healthy rearing of calves.