3. Effect of offering leaves or stems of water spinach on patterns of eating, consumption of caecotrophes and excretion of faeces by growing rabbits
Authors: Pok Samkol, Preston T R and Leng
R A 2006.
Livestock Research for Rural Development. Volume 18, Article #78. Retrieved July 8, 2006, from
Summary: Three experiments were conducted at the Center for Livestock and Agriculture Development (CelAgrid) located in Pras Theat village, Rolous commune, Kandal Stroeung district, Kandal province, Cambodia .
Experiment 1: Observations of time spent eating and defecating of rabbits fed either stems or leaves of water spinach. Four crossbred (Local x New Zealand White) rabbits with average live weight of 1625 ± 119 g were allocated to two treatments (WST: Stems of water spinach and WSL: Leaves of water spinach). The diets were fed ad libitum (about 120% of recorded intakes). The rabbits were housed in individual cages constructed from wood and wire mesh. The foliage was separated into stems and leaves and the proportions recorded. The feeds were offered in a trough, three times per day in the morning at 7:00 am, at 12:00 and at 4:00 pm. Feed intake was recorded from weights of fresh materials offered minus residue taken the next morning.
Experiment 2: Quantities of feed DM ingested, caecotrophes produced and faeces excreted by rabbits fed water spinach stems or leaves. Four crossbred (Local x New Zealand White) rabbits with average live weight of 1813 ± 136 g were used as in Experiment 1. Plastic collars were out around the necks to prevent the rabbits consuming the caecotrophes. Feed intake and production of caecotrophes and faeces were recorded every hour. Caecotrophes were not fed back to the rabbits. Samples of feed offered and refused and of caecotrophes and faeces were taken for analysis of DM.
Experiment 3: Composition of stomach contents in rabbits fed leaves or stems of water spinach. Twenty four crossbred (Local x New Zealand White) rabbits with average live weight of 1811 ± 301 g were designed in Experiment 1. Feed intake was recorded from 7.00 am until the time of slaughter, which began at 12:00 am with 2 animals being slaughtered every 4 hours. Samples of feed offered and refused, of caecotrophes and faeces and of stomach contents, were taken for analysis of DM, N, ash and crude fiber.
Abstract: Two experiments were done with crossbred rabbits (Local x New Zealand White) (range of live weight from 1600 to 1800 g), fed either stems or leaves of water spinach as sole diets. In the first study, observations were made of time spent eating, times spent consuming caecotrophes and voiding faeces. In the second experiment the effect on feed intake of depriving the rabbits of having access to the caecotrophes was monitored. The third experiment examined the composition of stomach contents of 2 rabbits on each diet slaughtered at 4 hour intervals over a 24 hour period. The rabbits consumed feed throughout the 24 hours. However, the consumption of caecotrophes was mainly during the day while faeces were voided only at night time. There were no differences between the two diets in the diurnal pattern of eating, consuming caecotrophes or voiding of faeces. However, total DM intake was higher when leaves were fed compared with feeding only the stems. The composition of the stomach contents, which included the caecotrophes, mirrored those of the diet with higher protein and lower crude fiber contents when the diet was water spinach leaves compared with stems. There were marked diurnal trends in the composition of the stomach contents during the 24 hours for the rabbits fed water spinach stems, with maximum values at midnight for DM and crude protein and minimum values for crude fiber. These trends were less marked on the diet of water spinach leaves
It was concluded that feeding water spinach leaves rather than stems resulted in a lower production of caecotrophes. It is suggested that the lower level of caecotrophs consumed on the leaves only diet may have reduced overall supply of protein and B vitamins (from caecal microbes). .Lower levels of caecal-produced nutrients of microbial origin could explain the poorer growth performance of rabbits observed in earlier trials when high offer levels of the water spinach led to increased selection of leaves at the expense of the stems.