TRAINING PERIOD AND SHORT TIME EFFECTS OF MACHINE MILKING ON MILK YIELD AND MILK COMPOSITION IN TUNISIAN MAGHREBI CAMELS (Camelus dromedarius)

Six healthy Maghrebi dairy camels at mid lactation were used in 2 trials to assess the camel training period for machine milking, and the short time effects of machine milking vs. hand milking on some milk production parameters and physicochemical characteristics in milk. Before the study, dams were reared in oasis intensive system and hand-milked twice. In trial 1 which lasted for 2 weeks, camels were trained for machine milking. In trial 2, camels were monitored during 2 successive weeks; on the first week they were hand-milked and on the second week, they were machine milked. Trial 1. Over days of training, the animals became less hostile and the total time between entering and exiting did not exceed 15 min. The lag time, after oxytocin injection, did not change and averaged 29.6 +/- 3.0 s. Nevertheless, milking time increased with the change of the milk production and averaged 7.5 +/- 0.4 min and 9.4 +/- 0.6 min, during the first and the second week, respectively. On the 2(nd) day of machine milking, daily milk yield decreased slightly (-6%) compared to the day (-2) before the start of machine milking. This production increased to 7.48 +/- 0.521 on day 13 of training. On the second week of the training period, no difference was observed between the daily milk yields. During training camels for machine milking, total milk solids, protein and ash contents did not vary. Milk fat was the most affected component, it decreased from 36.8 +/- 2.4 g/l 2 days before the start of machine milking until 28.7 +/- 1.8 g/l in day 10 of training period and returned to its initial value on day 13. Trial 2: Daily milk yield was 38% higher in machine than hand milking system. Milk secretion rate differed between the 2 milking systems. In the morning (8:00) as well in the afternoon (16:00), lag time was half shorter in machine milking (36.0 +/- 6.9 s) than in hand milking (58.0 +/- 4.0 s). However, milking time was longer in machine than in hand milking and ranged from 4.2 to 4.8 min and 2.6 to 3.2 min, respectively. Physical parameters of milk had higher values in machine than in hand milking system. However, in the morning, milk density was comparable between the 2 milking systems.