Effect of fat inclusion in diets for rabbits on the efficiency of digestible energy and protein utilization


  • C. Fernández Universidad Politécnica de Madrid
  • M.J. Fraga Universidad Politécnica de Madrid




Two hundred ten Californian x New Zealand White rabbits (117 males, 93 females) were usad to study the influence of diet, slaughter weight (2.0, 2.25, and 2.5 kg), and sex on the efflciency of dietary digestible energy (DE) and protein (DCP) utilization determined by using the comparativa slaughter technique. Seven diets were formulated to have the sama ADF level (24%), diet C had no added fat, diets T, O, and S contained 3% of added beef tallow, oleins, and soybean oil, respectively. Diets TWS, OWS, and SWS contained the same level and types of fat than diets T, O, and S but included also a 18% of toasted whole soybeans to increase dietary ether extract (EE) by 3%. Neither fat addition nor slaughter weight influenced DE efficiency, but when the dietary EE level and the weight at slaughter were increased, DCP efficiency increased (P<0.001) and decreased (P<0.05), respectively. Females had a greater DE and a lower DCP efficiencies (P<0.01) than mares. Diets containing soybean oil showed a higher DE efficiency than those containing oleins.


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