Nutritive value of Stylosanthes guianensis and Lablab purpureus as sole feed for growing rabbits

The objective of this study was to evaluate the nutritive value of Stylosanthes guianensis and Lablab purpureus as sole feed for growing rabbit. Thirty-six cross-bred growing rabbits of mean weight 515 ± 2.3g were used for the study. The animals were randomly allotted to 3 different treatments. The animals in T1 were fed S. guanensis only, while animals in T2 and T3 were fed solely on L. purpureus and sunflower leaf (control), respectively. Feed intake and weight gain were measured on daily and weekly basis respectively. The results showed that rabbits fed S. guanensis and L. purpureus compared favourably with those fed sunflower leaf in terms of feed intake, weight gain and feed conversion ratio. The results also revealed that the nutrients digestibility (dry matter, crude protein and crude fibre) were also better in rabbit fed S. guanensis and L. purpureus. The dressing percent, lung weight, heart and kidney weight were not affected by the dietary treatment.


INTRODUCTION
Rabbit is a micro-livestock that requires small space for production.It has short generation interval (Cheeke, 1984).The meat is tasty and contains high protein content with low cholesterol level and it could be started on small or large-scale (Omole et al., 2005).One of the major factors affecting livestock production in Nigeria is availability of quality feed at affordable price.Rabbits could utilize forages unlike poultry (Asuquo, 1997); they are pseudo-ruminant.Rabbit can be maintained on green leaves alone without the supplementation of concentrate, but for the best growth to be achieved by rabbits, forage has to be supplemented with concentrate feed.Alfalfa has been used as sole or in combination with other ingredients with high daily weight gain up to 35 g.Cheeke et al. (1983) evaluated the performance of rabbits on Alfalfa and some tropical legumes such as Desmodium distortum, Cassiatora and Clitonia termate, and the results were impressive.
Stylosanthes is a forage legume that is grown for fresh *Corresponding author.E-mail: omoleboye@yahoo.com.
feed, hay and commercial leaf meal production.It hasbeen used as plant protein source for pigs, ducks and chicken in China (Guptan and Singh, 1983).Lablab purpureus is leguminous plant that has been used to feed sheep, cattle and goat (Babayemi et al., 2006).Sunflower leaf is one of the common feed for rabbit in Nigeria.The objective of this study was to determine the effect of feeding growing rabbit solely on Stylosanthes guianensis and L. purpureus on growth, feed conversion ratio, carcass analysis and nutrient digestibility.

Experimental design
The experiment was conducted at the Rabbitary Unit of the Institute of Agricultural Research and Training, Moor Plantation, Ibadan which is located in the rain forest belt of South-Western Nigeria.The rabbits were reared in a wooden cage of 12 compartments.Each compartment had a dimension of 0.5 x 0.5 x 0.5 m 3 .The legs of the cage were placed inside a container containing used engine oil in order to prevent soldier ants' infestation.Thirty-six cross-bred growing rabbit of mean initial weight of 518.2 g were used for the trial.Completely randomized design was Means with different superscripts along the same row are significantly different (p<0.05).
used for the trial.The trial consisted of 3 treatments (T1 -T3) and each treatment was replicated 4 times with 3 rabbits per replicate.Rabbits in T1 were fed solely on S. guanensis while in T2 and T3, the rabbits were fed leaves of L. purpureus and sunflower, respectively.

Analyses
The initial weight of the rabbits was taken at the beginning of the feeding trial and subsequently at interval of one week with a weighing balance.Feed intake was taken on daily basis by deducting the leftover feed from feed given.Feed conversion ratio was also calculated.
The digestibility trial was carried out at the end of 12 weeks.Four rabbits were randomly selected from each treatment and housed individually.Feacal and urine were collected on daily basis, weighed and stored inside refrigerator.Seven days were used for the collection.At the end of seven days, the feacal was bulked for each animal for proximate analysis and the urine was bulked for nitrogen analysis.
For carcass analysis, four rabbits were randomly selected from each treatment.The rabbits were starved overnight before slaughtering.The fur was removed by scalding.The dressing percent was calculated as the ratio of dressed weight to live weight.Organs like kidneys, lung, liver and heart were removed and weighed individually.
Chemical composition of the S. guanensis, L. purpureus and sunflower and the feacal and urine sample were carried out according to A.O. A.C. (1990).All data were subjected to statistical analysis of variance and Duncan Multiple Range Test was used to separate the means (SAS, 1998).

RESULTS AND DISCUSSION
The results of chemical composition revealed that the crude protein of S. guanensis, L. purpureus and sunflower was high while their crude fibre also was high (Table 1).S. guanensis had low dry matter compared to L. purpureus and sunflower thus indicating that S. guanensis is more succulent than L. purpureus and sunflower.There were significant differences in the mean monthly feed intake of the rabbits (P<0.05).Rabbit fed S. guanensis gained more weight than those fed L. purpureus and sunflower (P<0.05).No significant difference was observed in L. purpureus and sunflower (P<0.05)(Table 2).There were significant differences in the mean monthly weight of the rabbit fed test diets (P<0.05).The highest weight gain was recorded in rabbits fed S. guanensis (P<0.05).The weight gain was relatively the same in rabbit fed L. purpureus and sunflower (P>0.05).
In Nigeria sunflower leaf is commonly used to feed rabbit and with the result obtained in this trial, the mean feed intake and weight gain, rabbit could be fed with either S. guanensis or L. purpureus.The mean daily weight gain observed in this trial was lower than 20 g/day reported by Lukefahr and Cheeke (1991) and this could be due to quality of the formulated feed used.It must be noted that rabbit in this study was fed solely on the forages.The highest weight gain reported in S. guanensis could be due to high protein content coupled with low fibre content compared to L. purpureus and sunflower.
The efficiency of feed utilization was better in rabbit fed S. guanensis than those fed L. purpureus and sunflower (P<0.05),thus buttressing the fact that S. guanensis and L. purpureus could be used to feed rabbit instead of sun-  (Babayemi et al., 2006;Odunsi et al., 2006) The nutrients (crude protein, crude fibre, ether extract) digestibility were better in rabbits fed S. guanensis compared to those fed L. purpureus and sunflower (Table 3).The better nutrients digestibility observed in rabbits fed S. guanensis could be as a result of high feed intake, low crude fibre content of S. guanensis compared to others and succulent nature of S. guanensis compared to L. purpureus and sunflower.It has been reported that crude fibre content, dry matter feed intake and crude protein of the diet have effect on nutrients digestibility (Arthur, 1975;Schiere, 1999).The results of carcass analysis (Table 4) revealed that the dressing percent, liver weight, dung weight and heart weight were not significantly affected by the dietary treatments.The dressing percent reported in this study was relatively similar to that of Awosanya and Akinyode (2000) and Orumuyi et al., 2006 In conclusion, S. guanensis and L. purpureus compared favourably in term of feed intake, weight, feed conversion ratio, nutrients digestibility and carcass analysis to widely common rabbit feed, sunflower leaf.The two leguminous plants are hereby recommended for farmer to cultivate for feeding rabbit.

Table 2 .
Summary of performance of growing rabbits fed S. guanensis, L. purpureus and sunflower.

Table 3 .
Digestibility of nutrients by rabbits fed S. guanensis, L. purpureus and sunflower leaves.

Table 4 .
Carcass analysis of rabbits fed S. guanensis, L. purpureus and sunflower.No mortality was recorded during the course of of the feeding trial as observed in Table2.Moreover, Lablab purpureus have been used to feed broiler chicken cattle, sheep and goat with proven good results which did not has any adverse effect on the health status of the animal