Abstract:
This trial was conducted in two phases during the period of February 2002 – June 2003. In phase 1 of the study the growth potential of calves fed either commercial Surromel Calf® (CSM) or experimental Surromel Calf (ESM) without calf starter was evaluated. In phase 2 of the study calves were fed either experimental Surromel Calf (ESM) or full milk with starter. High production cost and the availability of new technology prompted Clover SA to investigate other processes of manufacturing Surromel Calf®. The implementation of a new manufacturing process however, also necessitates evaluation of the end product. Twenty four Holstein heifer calves were used in a completely randomized block design. Calves were liquid fed only. For the first two weeks the milk replacer was allocated at 10% of body weight (2l fed twice daily), from week 3 to week 6 at 12.5% of body weight (2.5l fed twice daily) and during week 7 and week 8 calves received the milk replacer at 15% of body weight (3l milk fed twice daily). Water was available ad lib except for 30 minutes before and after milk replacer feedings. Body weight and skeletal development (body length, shoulder height, shoulder width and chest diameter) were measured weekly. The fecal consistency was subjectively scored daily. Mean average daily gains were 170g/day and 176g/day for calves receiving either ESM or CSM respectively. No differences were observed between treatments (P>0.05) for any change in body stature measurements over the 56 day trial period. If a price-competitive milk replacer could guarantee similar growth results as full milk, then milk producers would have confidence in using these replacers instead of full milk. In phase 2 of the trial calves were fed either 2l of full milk (FMS) or experimental Surromel Calf (EMSS) twice daily from birth up to 56 days. Calves had ad lib access to a commercial calf starter. Starter consumption was negligible for the first three weeks. Starter intake was 0.30kg/d and 0.34kg/d respectively at 35 days of age and 1.11kg/d and 1.10kg/d for FMS and EMSS calves respectively at 56 days (P>0.05). The average daily gain (ADG) were 370g/day and was unaffected by treatment (P>0.05). No differences were observed between treatments (P>0.05) for any change in body stature measurements. Growth standards for dairy calves with body weight less than 100kg have been included for the first time in the NRC Dairy 2001. Many producers are reluctant to use these recommendations since these have not been validated under South African conditions. The growth prediction was only compared with the growth of calves in Phase 2. The results showed that the NRC growth predictions are in agreement from week 3 onwards with the current study‘s growth results.
