(15) Effect of method of offering Water Spanish and Sweet potato vine to growing rabbits on feed intake, digestibility and feeding behavior

Doan Thi Gang**, Khuc Thi Hue**, Dinh Van Binh** and Nguyen Thi Mui*

* National Institute of Animal Husbandry, Hanoi
** Goat and Rabbit Research Centre, Son Tay, Hatay

Abstract

Thirty six weaned rabbits (New Zealand white breed) at 30 days of age, body weight ranging 0,7-1,0 kg/rabbit were used in an experiment to investigate the effect of method of offering Water Spanish and Sweet potato vine to growing rabbit on feed intake, digestibility and feeding behavior. The treatments were: (i) Water spinach hanging (WS), (ii) Water spinach hanging and Guinea grass (WSGG), (iii) Sweet potato vines hanging (SP), (iv) Sweet potato vines hanging and Guinea grass (SPGG), (v) Water spinach hanging + Sweet potato vines hanging (WSSP) and (vi) Water spinach hanging + Sweet potato vines hanging and guinea grass (WSSPGG). All rabbits were fed the same basal diet of molasses block at 5% of live weight containing 15% soybean meal + 25% cassava root meal + 20% rice bran + 5% minerals + 35% molasses. Water Spinach and sweet potato vines were hung by iron wire from the top and higher than floor of the cage about 5-7 cm. Higher dry matter intake was obtained in the treatments WSGG, SPGG, WSSPGG (149. 147 and 147 g DM/rabbit/day, respectively) than on the treatments without Guinea grass. There were no significant differences in average live weight gain (LWG) of growing rabbits in the treatments of WSGG, SPGG, and WSSPGG (26.4, 26.4, 27.2 g/day, respectively) and were higher than for WS, SP, WSSP (22, 21 and 23 g/day, respectively). Digestibility coefficients were higher for diets without guinea grass than with guinea grass (86.1, 84.5 and 84.9% vs 79.3, 71.3 and 77.1%, respectively for DM) and (84.7, 85.0 and 85.7% vs 75.6, 73.3 and 77.5% for protein). For feeding behavior, rabbits fed WS or SP as sole feed spent less time eating meals, more time drinking water and more time sleeping time compared to rabbits fed the mixed feeds of WSGG, SPGG, WSSPGG.. Time spent in caecotrophy was higher for rabbits on treatment WS and was higher at night compared to the day time. It is concluded that offering WS and SP roughage feeds by hanging in combination with Guinea grass is the best method for raising weaning rabbits.

Key words: Caecotrophy, feed intake, growth, guinea grass, rabbits, water spinach, sweet potato vines