Protocose as a Potential –Replacer for Rearing Calves

Abstract

The aim of this research was to investigate the possibility of using protocose, a by-product of starch and glucose industry, as a milk replacer for rearing suckling calves. After the extraction of glucose and starch from sorghum, protocose and other substances are produced as by-products. Protocose is very rich in crude protein (22.9%) and energy (16.3 MJ/kg), hence offering the possibility of introducing it as a cheap milk replacer. Sixty five male and female calves ranging between 2-3 weeks of age were chosen from the dairy herd of the Arab Company for Agricultural Production and Processing (ACAPP). They were divided into four groups and maintained for the entire rearing period until weaning at three months of age as follows: G1 was fed on whole fresh milk. G~ was fed on skim-milk G3 was fed on protocose G4 was fed on protocose + minerals The feeding regime adopted was as follows: In the first group, four litres (10% of body weight) of whole milk were offered, divided into equal morning and evening meals. The quantity was decreased gradually until weaning. In the second group skim-milk replaced whole milk gradually at the rate of 25, 50, 75 and 100%. This pattern was also followed in the protocose group (third group) where protocose replaced whole milk. In the fourth group, whole milk was replaced by mineralized protocose at the levels of 25 and 50% only. Statistical analysis showed that there were significant differences (P<0.0l) in the weekly weight gains between the four groups in the first, second, third, fourth, sixth and eighth weeks of the experiment, while there were no significant differences between the groups in the fifth, the seventh and the ninth weeks. The analysis of the data also indicated that the highest overall mean of daily weight gain was secured by group I (whole milk) followed by group II (skim-milk). Group IV (mineralized protocose) ranked third recording 89% and 95% of the daily gain of GI and GII, respectively. The poorest performance was that of GIII (protocose only) which attained 75% and 79% of the daily gains of GI and GII, respectively. The calves offered the protocose and protocose with minerals were also observed for the occurrence of any health problems. It was observed that there was no deleterious effect on the health of calves when protocose was fed at the level of 25 and 50%, however, increasing the percentage of protocose to 75 and 100% resulted in poor growth, scours, unthriftiness, rough coat, nasal discharge and lacrimation. No mortalities in the two groups were observed till the end of the feeding trial. This work was probably the first to investigate the possibility of using protocose derived from sorghum as a milk replacer for calves. Further research on the utilization of this cheap by-product for feeding suckling calves is needed. This will have a direct economic impact on the cost of rearing calves and will save substantial amounts of fresh milk for human consumption.