Abstract:
Calves are the foundation of the future dairy herd which signifies the importance of their proper rearing practices and needs to be performed at the herd and individual animal. This study was therefore conducted to assess calf husbandry practices in the urban dairy production system and to evaluate the effect of milk replacers on crossbred calf’s performance. The assessment was conducted in Dire Dawa city which was purposively selected based on its potential for dairy production. The data on farm characteristics and calf husbandry practices were collected by using semi-structured questionnaires from all available urban dairy farms owning at least one male calf and analyzed using simple descriptive statistics. Twelve Holstein crossbred male calves aged 3 days with an average initial body weight of 38.93±2.85 kg were purposively selected and randomly allotted to three dietary treatments. The treatment diets were designated as T1 (whole milk; control), T2 (commercial milk replacer), and T3 (locally formulated milk replacer) and fed to calves at a rate of 12%, 10% and 8% of body weight for first 30 days, 31-60, and 61-90 days, respectively. Data on feed intake, growth performance, and physiological, hematological, and serum biochemical parameters were measured for 90 days and analyzed by analysis of variance by using the GLM procedures of SAS, version 9.4. The result indicated that all dairy farms of the study area were reared under intensive management system, and they all (100 %) did not take calf birth weight, and kept their calves in shared pen calf housing type. The cow-calf separation was done at varying ages (soon after birth (≤ 6hrs) in majority of large and medium, and later than 24hrs in most small-scale sized farms). Most surveyed medium and large-sized farms offered three liters of first colostrum in the first 4hrs after birth and lasts for 3-4 days of postpartum. Non-saleable/waste milk was the main type of milk fed to male calves after colostrum feeding. Almost all dairy farmers of any herd size (92.53%) had no colostrum replacement products and they feed whole milk from other cows in replacement of colostrum, whereas 97.55 % of them managed surplus colostrum by feeding to other older calves. Calves fed on whole milk significantly (P<0.05) recorded the highest body weight change, body weight gain, and feed conversion efficiency. Calves fed on farm-formulated milk replacers (T3) significantly (P<0.05) exhibited the lowest values in total RBC count, Hb, MCV, and total
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cholesterol, and the highest values in blood urea. The results showed that farm-formulated milk replacer is 25,650.2 and 15,382.1 birrs less expensive than natural milk and commercial milk replacer, respectively. Generally, the study revealed that using farm-formulated milk replacers as a milk substitute for whole milk or commercial milk replacer had no adverse effect on the calf’s blood metabolites and health and would be economically advisable and profitable for dairy producers. Finally, it is permitted to fulfill the recommended objective of average growth or body weight higher than 90 kg at weaning and an average daily consumption of 2 kg DM/day of concentrate just before weaning. Efforts should be undertaken to educate dairy farmers about using waste milk without pasteurization for calves and general calf husbandry practices.