الفهرس 
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Abstract
The objectives of this feeding experiment were to evaluate effects of raising neonatal calves till weaning on different feeding regimes including whole milk (WM), milk replacer (MR), calf starter (CS) and concentrate mixture (CM) on growth performance (body weight, body weight gain, feed intake, body stature), fecal score and some blood metabolites as rumen development indicators of newborn calves. Twenty five Holstein newborn ♂ calves of almost equal body weight (average 40.3 kg) were divided from the first day of age into five equal groups and reared in separate wooden pens (5.5 m x 3 m) till weaning. Colostrum was fed for the first 3 days after birth, then the calves were switched over to the experimental feeding regime till 12th weeks (wk) of age. The calves in the first group fed on WM plus CM and good quality berseem hay till weaning. The second group fed on WM for 2 weeks, then replaced with MR plus CM and berseem hay till weaning. The used MR (Quality Milk®, Holland) contained 22% CP. The third group was offered WM plus CS and berseem hay till weaning. The calf starter was formulated to contain 20% CP. The fourth group fed on MR starting from the 5th d of age plus CS and hay till weaning. The fifth group was offered WM of 2 weeks followed by MR plus CS and hay till weaning. Concentrate intake, body weight, fecal score, body stature and selected serum metabolites were determined. At 12th wk of age, the calves groups received CS along with WM plus MR attained higher body weight (95.2 kg) than the calf-group fed WM or MR with CM (84.0 and 86.4 kg). Throughout the whole study, the fecal score was ranged from 2 to 2.14 for all groups and incidence of diarrhea was low. Regarding to the body stature, the calves fed WM+MR+CS had the highest body length, height and body depth than other groups. At 12th wk of age, calves fed only WM or WM+MR along with CM and hay had the lowest β-hydroxybutyrate value (0.308 and 0.362 mmol/L, respectively). However, blood glucose levels were higher for calves fed WM or WM+MR with CM (78.6 and 72.6 mg/dL, respectively) than other groups. In conclusion, it seems that raising neonatal calves on WM+MR+CS is the most suitable raising system regarding the body weight gain as well as body stature values and rumen developing followed by MR+CS system.