Effects of application of vitamin-mineral supplement in milk on performances of Holstein suckling calves

Introduction: Considering the breeding calves are one of the most important management programs in dairy farms and are the main farm profit, proper nutrition is important for their well-being. Calves do not eat enough solid feed in the first few weeks of life due to the lack of complete rumen development. Therefore, milk or milk replacer in this period is the most important source of energy and protein and other essential nutrients for the growth and health of calves. However, milk is a poor source of some minerals and vitamins for suckling calves. Aim: The objective of this experiment was to determine the effects of vitamin-mineral supplementation in milk on performances of Holstein suckling calves. Material and method: At day of birth, thirty Holstein suckling calves were randomly assigned to three treatments with 10 calves in each group from three to 60 days of age. The experiment was performed at four periods. Treatments were: (1) CON (no additives), (2) LMV (addition of 15 grams of mineral-vitamin supplement per liter of milk), (3) HMV (addition of 25 grams of mineral-vitamin supplement per liter of milk). Whole milk was fed to calves in two meals at 09:00 and 17:00. For all treatments, the same starter (20% protein and 3.3 Mcal/kg metabolizable energy) was fed to calves. Calves had free access to starter and water from the beginning of the experiment. Data were analyzed by mixed procedures of SAS (9.1) software. Results: Treatments had no effect on body weight changes and daily weight gain of calves (P 0.05). Calves in HMV treatment consumed less starter than CON calves, but showed better feed conversion ratio (P 0.05). Also, starter intake time was higher in the CON group than LMV and HMV calves (P 0.05). Dry matter digestibility increased (P 0.05) in LMV and HMV groups as compared with CON group. Blood metabolite analysis showed that total protein concentration was significantly higher in CON when compared with HMV (P 0.05). Conclusion: Improvement in the nutrients digestibility and feed conversion ratio of calves in LMV and HMV treatments resulted in lower starter intake, but the same final weight and daily weight gain of the suckling calves.