Zingiber officinale, a Phytogenic Feed Additive on Haematological and Serum Biochemical Indices of Yankasa Rams

Aims: The study was carried out to evaluate Zingiber officinale supplementation on haematology and serum biochemical properties of Yankasa rams. Methodology: Four complete experimental diets were formulated with graded levels of ginger at 0, 2.5, 5 and 7.5 g/kg inclusion levels. The four experimental diets were fed to twenty (20) intact male animals. A completely randomized experimental design (CRD) was used in the experiment with number of animals representing replication and graded levels of ginger representing treatments. Results: Results indicated no significant difference (P˃0.05) between treatment means on biochemical and haematological parameters (p˃0.05). Conclusion: It was concluded that ginger supplementation up to 7 g/kg did not have significant effect on the haematological and biochemical indices of Yankasa rams. Original Research Article Ibrahim et al.; JALSI, 5(3): 1-8, 2016; Article no.JALSI.26550 2


INTRODUCTION
Herbs and spices such as ginger have been reported to enhance activities of digestive enzymes and nutrient absorption in livestock animals [1]. Studies on phytogenic additives, antibiotics and organic acids have suggested similar effect on the gut function [1]. These include reduced bacterial colony counts, fewer fermentation products, greater nutrient digestion reflecting an overall improved gut equilibrium [2]. In addition some of the herbs and spices and their derivatives have been reported to promote intestinal mucus production. This effect led to improved production performance following inclusion in animal diet [2]. The biological properties, antimicrobial and antioxidant properties of essential oils of different aromatic plants have been known for long. Due to increased utilization and application of these products, a systematic study on these plant extracts has become very important [3].
The goal of the potential use of these sources is to modify rumen fermentation and increase the efficiency of the symbiosis between ruminant and rumen microorganisms in order to improve animal's performance without negative impact on the environment [4].
Hematological studies are of ecological and physiological importance in helping to understand the relationship between blood characteristics and the environment [5] and in the selection of animals that are genetically resistant to certain diseases and environmental conditions. Hematological parameters are good indicators of physiological status of animals [6] and those parameters that are related to the blood and blood forming organs. As reported by [7], animals with good blood composition are likely to show good performance. The examination of blood gives the opportunity to investigate the presence of several metabolites and other constituents in the body of animals and it plays a vital role in the physiological, nutritional and pathological status of an animal [8]. According to [9], examining blood for its constituents can provide important information for the diagnosis and prognosis of diseases in animals. Blood constituent's changes in relation to the physiological conditions of health. These changes are valuable in assessing response of animals to various physiological situations [3]. According to [10], change in hematological parameters is often used to determine various status of the body and determine stresses due to environmental, nutritional and pathological factors.
However, many supplements are used in animal feeds usually without recourse to health and physiological implications to the animals. Because ingestion of some of these dietary components have measurable effects on blood composition [11,12] and may have long term effects on animal's performance [13]; measuring these implications through haematology and blood chemistry becomes highly relevant [14]. This is because blood conveys different feed components to different parts of the body that could influence normal body function and affects health, growth, maintenance and reproduction of the animals [15]. While other studies deal with moderating the effects of environment, feeds, genetic, and other biological factors on sheep performance, the present study investigated the haematology and blood chemistry of Yankasa rams fed supplemented ginger levels in guinea savannah region of Nigeria.

Experimental Location
The experiment was conducted at the National Animal Production Research Institute (N.A.P.R.I.), Ahmadu Bello University (ABU), Shika, Zaria, Nigeria. Shika is geographically located at latitude 11°12'N and longitude 7°33'E at an altitude of 640 meters above sea level [16]. It is about 20 km along the Zaria -Sokoto road in Kaduna State, Northern Nigeria. It has three distinct climatic seasons which include the cold dry season (November-February), the hot dry season (March-May) and the wet season (June-October). The total annual rainfall ranges from 617 to 1365 mm with a 50-year average of 1041 mm [17]. Most of the rains fall between July and September. Zaria falls within guinea savanna vegetation zone. The mean maximum temperature varies from 26°C to 35°C depending on the season, while the mean relative humidity during harmattan (winter) period is 21% [17].

Experimental Animals and Their Management
Twenty apparently healthy intact male Yankasa rams of between 12-18 months of age were used for the experiment. The animals were procured from the Small Ruminant Research Programme unit of N.A.P.R.I. The animals were quarantined and put on adaptation to their new housing for two weeks. They were orally dewormed with albendazole (2.5% solution) to treat against gastrointestinal parasites. They were also treated with Oxytetracycline long acting broad-spectrum antibiotic based on the manufacturer's recommendation.

Sanitation and Health Management
Feces and urine were removed daily from the feeding pens to ensure adequate hygiene, less ammonia accumulation, optimal cleanliness of the experimental pens and ensure minimum discomfort and stress of the experimental animals. This practice was maintained for the entire period of the study.

Experimental Feed Preparation
Four complete experimental diets were formulated (Table 1) with graded levels of ginger at 0, 2.5, 5 and 7.5 g/kg inclusion levels. The four experimental diets were used for the trial. The diets were designated as diets 1, 2, 3 and 4 in the experiments. The formulation was done at the Feeds and Feeding Unit of the N.A.P.R.I. The ginger was sourced from local market and ground with peels before inclusion.

Experimental Design and Feeding Procedure
A completely randomized experimental design (CRD) was used in the experiment with number of animals representing replication and graded levels of ginger representing treatments. Five animals were allocated to each treatment and their pens were disinfected prior to the commencement of the experiment. The initial weights of the animals were balanced according to treatments. Each group was assigned to one of the experimental diets and fed in for 84 days. The experimental diet was fed according to the body weights (3% body weight) of the animals. The basal diet (Digitaria grass) was offered adlibitum three (3) hours after feeding the concentrate. Clean drinking water was also offered ad-libitum.

Data Collection
The data were collected in three phases, as follows.

Feeding trial
Body weight of each ram was taken at the beginning of the experiment (day 0). Subsequently, the rams were weighed weekly for body weight changes. Feed intake was measured and recorded daily by subtracting the left over from the quantity of feed offered to the animals the previous day. Feed conversion ratio was determined using feed intake and body weight gain. Nutrient intake was obtained from feed intake and chemical composition of the feed material. Feed and nutrient intake as % body weight was obtained from live weight and feed intake of the experimental animals.

Haematological assay
At the end of the feeding trial, 10 ml respective blood samples were collected from each of the animals for haematology, serum chemistry and electrolyte evaluation. Each blood sample was collected via the jugular vein into an ethylenediamine tetra acetic acid (EDTA) coated bottle which serve as anti-coagulant and a plain tube. Each sample was allowed to stand at room temperature and then covered, centrifuged, the serum decanted and deep-frozen for serum biochemistry. Labeled samples (5 ml each) of the whole blood were taken to the ABU Teaching Hospital Zaria, Chemical pathology and haematology laboratory for analysis as follows:

Haematological indices
Packed cell volume (PCV) and haemoglobin concentration were determined by the microhematocrit and cyanmethaemaglobin methods respectively as described by [16]. Erythrocyte count was determined by the haematocytometry method as described by [18].

Serum chemistry
The plasma total protein was measured using biuret reaction while albumin was measured by colorimetric estimation using Sigma® diagnostic kit according to the method described by [21]. Globulin was obtained by calculating the difference of total protein and albumin. The serum enzymes, Aspartate aminotransferase (AST), Alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were determined using a photoelectric calorimeter as described by [22]. Blood urea, nitrogen and creatine levels were also evaluated as described by [21].

Serum electrolytes
Serum sodium, calcium and potassium were determined using flame spectrophotometry as described by [22].

Statistical Analysis
The data generated from the experiment were subjected to analysis of variance (ANOVA) at 5% level of significance using completely randomized design using Statview Statistical Package [23]. Least significant difference (LSD) was used to separate the means.

Phytochemical Constituents and Intake
Phytochemical analysis of the ginger indicated a higher oxalate content followed by flavonoid, phenols, alkaloids and saponins in that order. Tannins were the lowest constituents in the sample material ( Table 2). Intake of the phytochemicals was higher for animals fed diets containing higher ginger levels and lower for the control diet. Dry matter intake (DMI) and average daily gain (ADG) of the animals decreased slightly with increased intake (Figs. 1 and 2). The values for alkaloids, saponins and tannins in ginger are similar to the values respectively reported by [24]. However, the value for flavonoid obtained in the present study is higher than those obtained by [24]. Although animals fed higher ginger supplementation have a reduced DMI, ADG was not significantly affected due to beneficial effects of some phyto-chemicals taken along with other nutrients. Beneficial effect of low to moderate concentrations of tannins to improve the digestive utilization of feed due to reduction of protein degradation in the rumen and a subsequent increase in amino acid flow to small intestine have been reported [25]. Saponins have also been found to enhance protection of protein from degradation in the rumen and increase bioavailability of protein post-rumination.

Haematological Parameters
MCHC (g/dl) is significantly higher for treatment 3 compared to treatment 4 (P˂0.01). There were no significant differences between treatments 2, 3 and 4 in terms of MCHC (g/dl) (P=0.05). All other parameters (PCV, Hb, WBC, RBC, MCV and MCH) showed no significant difference (P=0.05) between all the animals fed ginger (treatments 2, 3 and 4) irrespective of the inclusion levels.
The PCV values of 28.33-32.67% obtained in the present study were within the values 22.00-37.00% reported by [26] for normal healthy sheep. They are also close to 29.9-33.6% reported by [27] for clinically healthy sheep. The haemoglobin values 10.77-11.87% obtained in the present study are comparable to the normal reference values 8-16% as reported by [28]; so also the values of 23-48 fl and 31-38 g/dl for MCV and MCHC respectively. These suggest that even at the highest level of supplementation, ginger inclusion was not detrimental to the health of the animals. In addition, The PCV and Hb values are an indication that the animals were not anemic. For RBC, the range values of 12.03-12.90% obtained in the present study was above the range values of 2.40-4.20% reported by [26]. The values for WBC were above the normal range reported for healthy sheep by [25] suggesting the possible response of the animals to the effect of phyto-chemicals contained in the test ingredient. It has been reported that WBC in animals possesses phagocytic functions and are used as an indicator of stress and immune response to certain conditions [29]. The higher WBC reported in the present study further indicated that the animals seem to possess protective mechanism, providing a rapid and potent defense against infectious agents. This could be attributed to intake of some phytochemicals like flavonoids by the animals which functions in immune system by improving the activities of lymphocytes, macrophages, cells and increase phagocytosis as observed by [30].

Blood Chemistry
The blood chemistry parameters studied (   reported by [32]. K is important for regulation of acid-base balance in the body. The values of K obtained from this study were within the range 5.13-5.60 mmol/l reported by [33]. The same observation was also made for Ca as obtained by [34]. The effect of dietary treatments was not significant (p˃0.05) on the total blood protein levels of the animals. The creatine and albumin were slightly higher to the normal reference values reported by [35]. The creatine level could be attributed to the growing stage of the animals because it increases with increase in age as observed by [36]. Bicarbonate, AST and Chlorine are within the normal ranges. Though the ALP is slightly higher; high ALP may indicate a liver problem and alkaloid toxicity. However, high levels of ALP can be normal in growing animals due to growth of bones [37]. The ALP being high is an indication of high protein intake. The AST value was not high enough to impede liver function of the animals. ALT also falls within the reference range [37].

CONCLUSION
It was concluded that ginger supplementation up to 7.5 g/kg did not have significant effect on haematology and blood chemistry of Yankasa rams. Future research should be conducted with varying inclusion levels on haematology and biochemical indices of the animals.