Introduction

Haematological parameters are those parameters that are related to the blood and blood-forming organs¹. The haematological and lipid serum examination is among the methods which may contribute to the detection of some changes in health status, which may not be apparent during physical examination but which affect the fitness of the animals ².

Tiger nuts (Cyperus esculentus), an unexploited and under-utilized food is a grass like plant of the family Cyperaceae (sedge family) and is widely distributed in many north temperature locations within South Europe as its probable origin³. Tiger nuts are cultivated in many countries of West Africa and a lot of people eat the tiger-nut without knowing the health benefits. They have been cultivated both as a livestock food and for human consumption of the tubers, eaten raw or baked. Tiger nuts tuber has been shown to have several effects in the body. It is believed that they help to prevent heart attacks, thrombosis and cancer especially of the colon⁴,⁵, relieve indigestion especially when accompanied by halitosis, beneficial to diabetics and those seeking to reduce cholesterol or lose weight, hasten the inception of menstruation ⁶. Along with a high-energy content (starch, fats, sugars and proteins), they are rich in minerals such as phosphorous and potassium and in vitamins E, C, soluble glucose and oleic acid. Typically, 100g Tiger nuts contain 386 kcal (1635 kj) as 7% proteins, 26% fats (oils), 31% starch, 21% glucose. They contain 26% fibre of which 14% is non-soluble and 12% soluble ⁷, ⁸. They have excellent nutritional qualities with a fat composition similar to olives and a rich mineral content, especially phosphorus and potassium. The oil obtained from Cyperus esculentus is golden brown in colour and has a rich, nutty taste. The oil of the tuber was found to contain 18% saturated (palmitic acid and stearic acid) and 82% unsaturated (oleic acid and linoleic acid) fatty acids ⁸. However, information and knowledge on the effect of the tuber oil meal-based diet on the haematological parameters of rats is still very scanty in literature and remains incomplete. The present study was therefore carried out to assess the effect of tiger nut oil meal-based diet on the haematological parameters of rats.

Materials and method

Collection and preparation of seed sample:

Oil Extraction

Purification of the extracted oil

Feed Formulation:

The purified tiger nut oil and soybean oil were used as a source of fat in the formulation of animal feed. The diet for each group was formulated by mixing known quantities of sources of each food class (Table 1). The food items were mixed together and manually made into pellets to feed albino rats.

Figure 1

Table 1: composition of diets

Animal Management:

Collection and Treatment of Blood Samples:

Statistical analysis

All data were analyzed statistically using Analysis of Variance (ANOVA) test ¹². Significant difference between the treatment means was determined at 5% confidence limit using Duncan's Multiple Range Test ¹³.

Result

Table 2 shows the proximate analysis of the formulated diets (test and control) on which the rats were maintained. There was no significant difference (p>0.05) in the various components of the diets.

Figure 2

Table 2: Proximate composition of compounded

The haematological parameter of rats fed with soybean oil and Tiger nut tuber oil based diets are shown in Table 3. There was no significant difference in all the Haematological parameters in the serum of Tiger nut oil based diet fed rats as compared to that of the soybean oil.

Figure 3

Table 3: Comparism of the Hematological Indices In Control And Tiger nut oil Fed Rats.

Discussions

Nutritional status of an individual is dependent on dietary intake and effectiveness of metabolic processes. These can be determined by either or combinations of clinical, anthropometric, biochemical or dietary methods. The first worthy statement about the study is that none of the animals specimen died either naturally or due to feed ingestion The values obtained from proximate analysis of the formulated diets (Table 2) compared favourably with each other, indicating that the rats in both groups were placed on the same amount of nutrients quantitatively and therefore whatever differences that are noticed might be due to the differences in the quality of the nutrients in these diets or their bioavailability when consumed.

The absence of significant difference as shown in Table 3 among treatment groups for the hematological parameters added to the absence of mortality suggested tiger nut tuber oil is not toxic. It has been reported that the measurement of anaemia gives an indication of the severity of the disease ¹⁴. Packed cell volume is the volume by percentage of red cells in whole blood. The non significant reductions in the haematological parameters contents of the blood of rats reared on the oil based meal of tiger nut and soybean based meal is an indication that the oxygen carrying capacity of the animals’ blood is not reduced. The major function of the red blood cells is to transport haemoglobin, which in turn carries oxygen from the lungs to the tissues ¹⁵. The Hb concentrations and haematocrit are values revealing the degree of anemia while the MCHC is a useful index of the average Hb concentration of the red cells ¹⁶. Generally, low readings for RBC, Hb and hematocrit can indicate anaemia. Leucocytes are known to increase sharply when infection occurs, as one of the first line of defense of the body ¹⁷ .The increase in total while blood cell count, neutrophils, lymphocytes and monocytes counts following tiger nut oil feeding for 6-weeks confirms the anti-infection properties of tiger nut. According to Robins (1974), in a toxic environment, RBC count significantly decreased while WBC increased but such is not experienced in this study. The hemoglobin and packed cell volume of the rats were within acceptable range suggesting adequate iron status. This could be associated with the iron content of tiger nut oil which is a good source of non-heme iron ¹⁹. Non-heme iron from plant sources has been reported not to be as readily available to the body as heme iron from animal sources which are well absorbed ²⁰. A non-significant difference in platelet number of control and test serves as an absence of marker disease such as microangiopathy and macroangiopathy ²¹. Thus, confirming Tigernut trader (2005) that tiger nut tuber oil may not contribute to the risk for cardiovascular diseases.

Conclusion

In conclusion, the various dietary treatments did not significantly affect the serum components meaning that the oil might be toxicological free. These findings, in effect show that this plant oil if adequately processed could substitute for expensive animal sources which are out of the reach of the poor. This confirms that the test diets are adequate for maintaining healthy nutrition status in weanling rats. Further work needs to be conducted on the effect of tiger nut oil on some selected organs in rats.