Study of the Effects of Different Levels of Garlic Waste Powder on Growth Performance, Blood Metabolites and Antioxidant Activity in Suckling Holstein Male Calves

Introduction
With the awareness of the increasing misuse of antibiotic growth promoters in the livestock and poultry industry on human health, due to their deposition in milk and meat, and on the other hand, the increasing concern about the development of resistance in pathogenic bacteria of humans and livestock, it has led to an increase in the demand for safer and natural alternatives to control diseases and increase production efficiency in the livestock and poultry farming industry. (Tan et al., 2022) Therefore, non-pharmaceutical and non-antibiotic additives, such as medicinal plants, organic and inorganic acids, prebiotics and probiotics, are used as growth and immune system stimulants in livestock and poultry nutrition. Medicinal plants can promote growth, modulate the immune system, and reduce the harmful effects of pathogenic organisms due to their secondary metabolites. Also, due to their antimicrobial, antiparasitic, antiviral, anti-inflammatory, and antioxidant properties, as well as their stimulating effect on the digestive system of animals, they can be a suitable alternative to pharmaceutical antibiotics. (Skoufos et al., 2020) Garlic plants modulate metabolic processes, thereby improving digestion and absorption. Garlic and its products are rich in bioactive organic sulfur compounds such as allicin, allixin, and allyl sulfides, which give garlic products antimicrobial, antioxidant, anti-inflammatory, immunomodulatory, antihypertensive, cancer prevention, anti-lipidemic, and other physiological properties. The medicinal and antibiotic properties of this plant are due to the presence of a sulfur compound called allicin. Allicin is the main active component of organic sulfur compounds, which constitutes more than 90% of the total organic sulfur compounds in garlic powder. In addition to increasing the digestibility of dry matter, crude fiber, crude protein, nitrogen-free extract, and organic matter, the addition of garlic powder improves the average daily weight gain and feed conversion ratio of lambs. The recommended positive effective dose varies from 20 to 50 grams per kilogram of dry matter in a trial period of 55 to 100 days of age. (Kewan et al., 2021) It can also increase the diet's palatability, which in turn increases appetite and nutrient intake. (EI-Naggar and Ibrahim, 2018) Many studies have also reported the effects of strengthening the immune system, including reductions in certain blood plasma biochemical parameters, such as cholesterol, as well as antibiotic and antifungal properties. (Hashemi et al., 2010) According to the available information, this study was designed and conducted to investigate the effects of different levels of garlic waste powder on growth performance, blood metabolites, and antioxidant activity of suckling Holstein male calves.
Method
For this purpose, garlic waste (including stems, skins, and broken bulbs) from garlic fields cultivated in the Moghan plain was first dried and then ground into powder using a home grinder and finally used to investigate the effects of the resulting powder on growth performance, blood metabolites, and antioxidant activity in male Holstein suckling calves.
This study was conducted at the livestock complex of Mughan Agriculture, Industry, and Livestock Company located in Parsabad, Iran country. For this purpose, 40 male Holstein suckling calves, with an average age of 14 days and an average weight of 42.9 kg, were used in a completely randomized design with 4 treatments and 10 replications over 56 days. The experimental treatments included: 1) starter feed without additives, 2) starter feed containing 1% garlic waste powder, 3) starter feed containing 2% garlic waste powder, 4) starter feed containing 3.5% garlic waste powder.
Results
The addition of 3.5% garlic waste powder to the initial diet of male suckling calves resulted in the greatest increase in body weight on days 28 to 42 and 42 to 56. The results show that the use of 3.5% garlic waste powder in the initial ration of suckling male calves at ages 14 to 28, 28 to 42, 42 to 56 days, and for the whole period significantly increased feed consumption compared to other experimental groups. The results showed that the feed conversion ratio was significantly improved with the addition of 3.5% garlic waste powder in the early years of male infants, on days 14 to 28, 28 to 42, and for the whole period, compared to other treatments. The addition of 2 and 3.5% garlic waste powder in the initial diet of infant calves significantly improved the serum concentration of cholesterol, aspartate aminotransferase, alanine aminotransferase, and glutathione peroxidase compared to other groups. Also, the addition of 3.5% garlic waste powder to the initial feed could significantly reduce the blood malondialdehyde concentration and increase the plasma superoxide dismutase and total antioxidant concentrations compared with other experimental treatments.
Conclusions
The results of this research show that adding garlic waste powder to the starter diet is an effective and economical solution to improve the production performance and health status of suckling male calves. Considering that the 3.5% level of garlic powder, in addition to the significant increase in weight gain and feed consumption, has led to the improvement of the feed conversion ratio and the improvement of the antioxidant status of livestock (reducing oxidative stress), this level can be suggested as a natural and efficient additive in the starter diet.