Effect of Different Levels of Dried Delonix regia Seed Meal on the Performance, Hematology, Serum Biochemistry of Growing Grass Cutters

Livestock production in Nigeria is faced with a lot of problems, one of which is high feed cost. According to Ekenyem [1], feed cost represents about 70-80% of the total cost of production. The increase in the prices of conventional feedstuffs like soya meal, fishmeal and maize which are highly used in the production of animal feed, flour milling, oil industries as well as human consumption is as a result of the competition between humans and animals for grains and upward increase in human population. Profit cannot be maximized unless birds are we fed well formulated diets at reasonable cost to meet up with their nutritional requirement therefore there is need to look for cheaper alternative sources of feed ingredients to feed livestock. For instance, Delonix regia seed is a non-conventional feedstuff of the family Caesalpiniaceae, the tree is commonly known as “flamboyant” or “flame tree”. According to Andrea et al. [2], the tree is known to reach a height of approximately 12 metres and the flowers shows colours ranging from orange and red. Kumar et al. [3], reported the presence of alkaloids, flavonoids, phenols and cardiac glycosides during phytochemical screening of D. regia. According to Esonu et al. [4], proximate components of Delonix regia seeds revealed 20.50%, 4.23% and 6.84% for crude protein, ether extract and crude fibre respectively. Grass cutter (Thryonomys swinderianus) also known as cane rat is a wild hystericomorphic rodent widely distributed in the African sub region and exploited in most of areas as a source of animal protein [5,6]. The colour of the fur is brownish, coarse and thin. Omole et al. [7], also reported that the protein content in the meat is about 20% which compares favorably with other sources of animal protein, the mineral content of the meat contains major minerals such as calcium, phosphorus and iron which are needed for metabolic activities in the body, strong bone formation, regulation of hormonal activities and utilization of other minerals. Grass cutters can utilize high fibrous and cellulose fraction of a feed more than poultry [8,9]. Martin [10], also reported that the animals can adapt to harsh environment and can utilize natural resources and digest most form of edible green stuff ranging from coarse grasses to roughages and household scraps.


Introduction
Livestock production in Nigeria is faced with a lot of problems, one of which is high feed cost. According to Ekenyem [1], feed cost represents about 70-80% of the total cost of production. The increase in the prices of conventional feedstuffs like soya meal, fishmeal and maize which are highly used in the production of animal feed, flour milling, oil industries as well as human consumption is as a result of the competition between humans and animals for grains and upward increase in human population. Profit cannot be maximized unless birds are we fed well formulated diets at reasonable cost to meet up with their nutritional requirement therefore there is need to look for cheaper alternative sources of feed ingredients to feed livestock. For instance, Delonix regia seed is a non-conventional feedstuff of the family Caesalpiniaceae, the tree is commonly known as "flamboyant" or "flame tree". According to Andrea et al. [2], the tree is known to reach a height of approximately 12 metres and the flowers shows colours ranging from orange and red. Kumar et al. [3], reported the presence of alkaloids, flavonoids, phenols and cardiac glycosides during phytochemical screening of D. regia.
According to Esonu et al. [4], proximate components of Delonix regia seeds revealed 20.50%, 4.23% and 6.84% for crude protein, ether extract and crude fibre respectively. Grass cutter (Thryonomys swinderianus) also known as cane rat is a wild hystericomorphic rodent widely distributed in the African sub region and exploited in most of areas as a source of animal protein [5,6]. The colour of the fur is brownish, coarse and thin. Omole et al. [7], also reported that the protein content in the meat is about 20% which compares favorably with other sources of animal protein, the mineral content of the meat contains major minerals such as calcium, phosphorus and iron which are needed for metabolic activities in the body, strong bone formation, regulation of hormonal activities and utilization of other minerals. Grass cutters can utilize high fibrous and cellulose fraction of a feed more than poultry [8,9]. Martin [10], also reported that the animals can adapt to harsh environment and can utilize natural resources and digest most form of edible green stuff ranging from coarse grasses to roughages and household scraps.
instance Ishaya B Kaga [11]; Szendro et al. [12], reported a significant (P<0.05) difference in final live weight and feed conversion ratio of rabbits fed with D. regia meal. However, there is a dearth of information on the effect of D. regia meal on grass cutter's performance and blood profile when included in their diet. Therefore, this study was carried out to investigate the effect of partial replacement of dietary Soya meal with D. regia meal in grass cutter's diet.

Location of experiment
The experiment was carried out at the University of Abuja Teaching and Research Farm, Animal Science Section, Main Campus, along Airport Road, Gwagwalada, Abuja-Nigeria. Gwagwalada is the headquarters of the Gwagwalada Area Council; located between latitude 80 57I and 80 55IN and longitude 70 05I and 70 06IE. The temperature of Gwagwalada ranges from 28 ˚C -33 ˚C in the day time and 22 ˚C-25 ˚C in the night.

Collection and processing of test materials
Matured pods of Delonix regia were collected from a tree within the premises of the University of Abuja, the seeds were removed from the pods, first washed with running tap water and then with distilled water, shade dried without any contamination for 10 days and passed through a hammer mill to produce D. regia meal (DRM). The sample was later kept in an air tight container for further analysis.

Experimental animals and their management
Fifty (50), 7 weeks old weaner grass cutters of mixed breed and sex with a weight range of 630 and 635grams were randomly assigned to five treatments of twelve (10) grass cutters per group, each treatment was replicated three times with each replicate having nine grass cutters in a completely randomized design. The hutches were cleaned and disinfected before the arrival of the animals. The grass cutters were allowed one-week adjustment period during which they were fed with control diet and given prophylactic treatment of Promectin against endo and ecto-parasites before they were placed on experimental diets. The animals were individually housed in cages measuring 30cm×45cm×50cm (width × length × height) and equipped with feeding and watering troughs. The rabbits were fed twice daily at 7.30h and 14.30H while water was provided ad-libitum.

Preparation of experimental diets
The test material (DRM) were mixed with other ingredients to form five experimental diets at levels of 0, 5, 10, 15 and 20% as presented in Table 1.

Growth performance parameters
Daily feed intake (g) was calculated by difference between feed offered and the left over, feed conversion ratio was determined as feed intake divided by body weight gain, water consumption and mortality were recorded daily throughout the experimental period which lasted for 7 weeks.

Blood analysis
At the 7 th week of the experiment, blood samples were collected from the veins of four randomly selected rabbits per group. The blood samples were analyzed for some hematological and serum biochemical parameters; blood samples for hematology were collected into bottles containing Ethylene Diamine Tetra Acetate (EDTA). The hematological parameters such as Pack cell volume (PCV), Red blood cell (RBC), White blood cell (WBC), Haemoglobin concentration (Hb) and absolute counts of neutrophils, lymphocytes, monocytes and eosinophils were computed according to the method of Jain [13].
Blood samples that were meant for serum chemistry were collected into bottles free of any anticoagulant. It was centrifuged at 1500 r. p. m for 10 minutes and the serum was separated and analyzed. Albumin, globulin and serum total protein were determined by Biuret reactions [14], and cholesterol [15]. Activities serum of serum glutamic pyruvate transaminase (SGPT), serum glutamic pyruvate transaminase (SGOT) were determined colorimetrically [16]. Activities of total glucose and cholesterol levels were determined as described by [17].

Proximate analysis
The proximate components were determined by the AOAC [18]. Phytochemical screening was determined according to procedures outlined by Kumar et al. [3]. The mineral analysis was carried out using Atomic Absorption Spectrophotometer (AAS).

Statistical analysis
All data obtained from the study were subjected to analysis of variance (ANOVA) procedure of SAS [19], in a completely randomized design and significant means separated by Duncan multiple range test [20].  [4], as presented in Table 2.    Table 5.    1, 191.1, 193.4, 193.7 and 194.2 (mg/g) for treatments 1, 2, 3, 4 and 5 respectively while those of creatinine (mg/g) are 1.14,

Discussion
Crude protein level in the experimental diet falls within the range recommended by Kusi et al. [21], for growing grass cutters. The grass cutter final live weight ranges between 984.6g and 1501g, there was a significant difference (P<0.05) among the treatments in terms of the final live weight. The best performance was observed in grass cutters fed 8% DRM (T5) they had the lowest feed consumption and daily weight gain those fed 0% DRM (T1) had the lowest weight gain of 6.24 g/grass cutter/day. This is a clear indication that the protein level in the experimental diet can adequately support the growth of the animals and the report agrees with the findings of Ishaya Kaga [11]; Alagbe et al. [22], but contrary to the reports of Saulawa et al. [23]; Salisu et al. [24]; Banjo et al. [25], when brewer's dry grain was replaced in the diet of weaner grass cutters. No mortality was recorded was recorded among the treatment different treatment groups throughout the experimental period. This could be due to the medicinal nature of Delonix regia seeds. According to Amata & Nwagu [26], D. regia seeds have multiple biological activities, including antiviral, anti-ulcer and antibacterial properties attributed mainly to their antioxidant activity. Proximate and phytochemical analysis reveals the presence of some bioactive compounds and minerals which are also in accordance with the findings of Roy et al. [27]; Kumar et al. [3]. Zinc had the highest mineral content of 9.77mg/kg followed by manganese with 6.21mg/kg, calcium had the lowest value of 2.17mg/kg. According to Gupta et al. [28]; Prasad [29], and Andrea et al. [2], zinc have been reported to perform anti-inflammatory and antioxidant activities. Magnesium, calcium and phosphorus are also proper red blood cell formation [30].
Watts [31]; Gupta et al. [28], also reported that minerals are very important for proper enzymatic activities in the body and can be grouped into macro and micro minerals. Insufficient amount of minerals in the body can lead to deficiency. For instance, copper deficiency could lead to osteoporosis, calcium and phosphorus deficiency can affect the structure of the bone.
Phytochemical screening revealed the presence of tannins, phenols, saponin, flavonoids, alkaloids and oxalate confirming the findings of Parekh et al. [32]; Kavitha et al. [33], and Naveen Prasad [34], but contrary to the Oyediji et al. [35], who reported that tannin, oxalate and saponin contains 1.28, 2.57 and 2.89 respectively, this could be due to differences in the environmental conditions where the plant is found. According to Kennedy et al. [36], phytochemical parameters can be altered during period of extreme stress and weather conditions. High level of anti-nutrients (phytochemicals) can prevents the absorption of minerals which are necessary for body metabolism [37]. Anti-nutrients present in DRM did not have any adverse effect on the performance of the grass cutters.
The hematological parameters were not significantly influenced (P>0.05) with the inclusion of DRM in the diets, this could be attributed to nutritional adequacy and safety level of DRM. The values for all parameters fall within the normal range established for grass cutters by Okpara et al. [38]; Byanet et al. [39]. According to Iheukwumere & Herbert [40]; Kurtoglu et al. [41]; Afolabi et al. [42]; Nse Abasi et al. [43]; Etim et al. [44], hematological parameters are useful tools to determine stress due to nutrition, health and physiological state of animals. Bamishaiye et al. [45], posited that hematological parameters are related to blood and blood forming organs.
Red blood cell (RBC) is responsible in carrying oxygen and carbon dioxide in the body [46], it also contains a red pigment known as hemoglobin. Soetan et al. [47], reported that a reduction in RBC value implies a reduction in the level of oxygen that would be carried to the tissues as well as the level of carbon (IV) oxide returned in the lungs. The values of Hb, PCV, RBC, MCV, MCH and MCHC could be a clear indication that the animals were well nourished, and possibility that DRM was able to supply all the essential nutrients necessary for the proper functioning of the animal's body. According to Issac et al. [46]; Ugwuene [48]; pack cell volume (PCV) is involved in the transportation of absorbed nutrients. Hb and MCH are major indices for the diagnosis of anemia.
The WBC values slightly increased as the level of DRM increased though not at a significant level, high values of white blood cell count and its differentials is a sign of resistance to disease, WBC counts suggests a greater challenge to the immune system. According to Eheba et al. [49], a decrease in the WBC count reflects a fall in the production of defensive mechanism to combat infection. Animals with low WBC are exposed to high risk of disease infection, while those of high counts are capable of generating antibodies and have a high degree of resistance to diseases Soetan et al. [47]; Gotoh et al. [50]. Eosinophils and basophils are effector cells in allergy and host defense responses particularly against parasitic infections [51].
The total protein, albumin, globulin, urea, creatinine and alkaline phosphatase of the grass cutters used in this experiment were not affected (P>0.05) by DRM inclusion, this is a clear indication that the protein and minerals contained in the diet is enough to support the normal protein reserves across the treatments. The values obtained fall within the normal range reported by Okpara et al. [38], on hematology and plasma biochemistry of the wild adult grass cutters, the total protein did not follow any specific pattern, this agrees with the findings of Alagbe et al. [22], when dried shear butter leaf -neem meal mixture were fed to broilers but contrary to the reports of Obikaonu et al. [52]. High uric acid and creatinine are measure of amino acid degradation [41], blood proteins are usually affected by level of nutrition [53].
The non-significant (P<0.05) difference in the values obtained for Na+ and Cl-across the treatment group is a clear indication that the kidney was not damaged or negatively affected. SGPT and SGOT values did not show serious consistency, ALP values also reduced as the inclusion of DRM increased. According to Obikaonu et al. [52]; Iyayi [54], ALP, SGPT and SGOT values are usually affected when a test material fed to an animal contains some toxic substance which could damage some vital organs like the liver, intestine and kidney [55,56].

Conclusion
The results obtained from this study clearly demonstrated that DRM could be efficiently utilized and tolerated by grass cutters up to 8.0% inclusion level without any deleterious effect on performance and health status of the animals.