Replacement of animal origin feed by plant origin feed in the diet of broiler chickens

摘要

The main goal of this study was to test diets that were specially formulated for the fattening of broiler chickens and in which feed of animal origin (meat-and-bone meal) was utterly replaced by feed of plant origin (Proenergol - treated rape expellers). The results obtained in this study proved that this type of diet was suitable for the fattening of broiler chickens. At the end of the fattening period (on the 42nd day) the average liveweight of chickens in the control group was practically identical to that of the experimental group; i.e. 2.13 kg and 2.10 kg for pullets and 2.34 kg and 2.31 kg for cockerels. On the 14th day, the average weight of both pullets (P less than or equal to 0.05) and cockerels (P less than or equal to 0.01) in the experimental group was higher than that in the control group. On the 35th day of the fattening period, the average weight of cockerels in the experimental group was found to be higher than that in the control group (P less than or equal to 0.05). Furthermore, diets free of animal origin feed affected neither carcass weight nor carcass yield. According to the evaluation of the weight and yield of abdominal fat, neither diet showed any significant effect on the content of fat in carcass. On the 42nd day of the fattening period, haematological and biochemical analyses of blood plasma of chickens were performed. These analyses revealed that the average values of plasma protein in chickens of the control group (34.56 g/l for pullets and 33.92 g/l for cockerels) were significantly lower (P less than or equal to 0.01) than those in the experimental group (37.34 g/l for pullets and 36.44 g/l for cockerels). Similarly, plasma phosphorus was 2.44 mmol/l in pullets and 2.15 mmol/l in cockerels of the control group compared with 3.12 mol/l and 2.54 mmol/l in pullets and cockerels of the experimental group. On the contrary, the average plasma concentrations of magnesium were significantly higher (P less than or equal to 0.05) in both pullets. (0.83 mmol/l) and cockerels (0.81 mmol/l) of the control group in comparison with those in the experimental group (0.77 mmol/l for pullets and 0.72 mmol/l for cockerels).