Effect on weanling rabbits of the addition of polyethylene glycol, phytase, methionine and choline chloride to diets containing black locust

Forty New Zealand White weanling rabbits were fed diets containing 50% alfalfa (control), 25% alfalfa and 25% black locust leaf meal (BLM) (BLM control), BLM + 1% polyethylene glycol (PEG), BLM + 1% phytase, and BLM + 0.3% L-methionine and 0.3% choline chloride. The digestibilities of dry matter (DM), crude protein (CP}, ADF, NDF, ash, calcium and phosphorous were significantly higher for the 50% alfalfa control than for the BLM treatments (respective p values < .01, .01, .01, .01, .01, .01, .01). The average daily gain was higher for the control (p < .01) and feedfgain was lower (p < .Ol) than for the BLM treatments. The lower utilization of nutrients in the BLM diets is probably due te the presence of condensed tannins. The addition of PEG increased CP (p < .01) and ADF (p < .03) digestibilities compared te the BLM control. The addition of Lmethionine and choline chloride increased ADF digestibility (p < .02) compared te the BLM control. It was concluded that PEG is partially effective in alleviating the reduced nutrient availability due te tannins.