NEMATOCIDAL ACTIVITY OF METHANOLIC EXTRACTS OF LEAF, STEM BARK AND ROOT OF AZADIRACHTA INDICA A. JUSS. (NEEM) AGAINST HAEMONCHUS CONTORTUS(RUDOLPHI 1803) COBB 1898
abstract
Azadirachta indica root, stembark, and leaf methanolic extracts were tested in vitro against Haemonchus contortus larvae for their antihelminthic activity. Carbohydrates, cardiac glycoside, saponins, flavonoids, tannins, and alkaloids were all found in the extracts of all the plant parts, as well as triterpenes in the stembark and root and steroids in the leaf. Alkaloids and tannins had the lowest quantitative percentages, followed by flavonoids with a high percentage of flavonoids (20.21, 27.50, 20.95), followed by 5.25, 5.48, 5.48, 4.95, 4.93, 4.15, and 0.75, 0.68, 0.67, respectively. H.contortus eggs were cultured in culture plates kept in an incubator at 27°C. The 7-9 day old sterile faecal cultures were where the infectious third stage larvae (L3) were found. The harvested larvae were concentrated for 15 minutes at 1000 rpm. 120 L3 larvae in 0.1 ml of a microtitre plate wells were added, along with concentrations of the extracts (leaf, stembark, and root) at 0.1 mg/ml, 1.0 mg/ml, 10.0 mg/ml, and 100 mg/ml, a negative control (water), and a positive control (levamisole), with six replications. After the treatments were added, it was examined under a microscope once every six hours for 48 hours, and the number of fatalities was noted. The leaf’s lethal concentration (LC50/EC) is 12.30 mg/l, the stem bark’s is 12.58 mg/l, and the root extract’s is 15.84 mg/l. The concentration and duration of exposure both increased the parasites’ mortality rates. During the highest exposure period (48 hours) and at the highest Mortalities were higher at concentrations of 100 mgml-l than at exposure times as short as 6 hours and as low as 0.1 mgml-1. The data revealed incredibly significant differences (p=0.001) between the plant parts, exposure time, extract concentration, exposure time and concentration, and between the plant parts and concentration. Despite the fact that parasite mortality increased over time, there were no differences that were statistically significant between the plant parts and the exposure time (p=0.92) or between the plant parts, exposure time, and concentration (p=0.99). While mortality rates in the positive control wells were high and rose as exposure time increased, no deaths were noted in the negative control wells. The study finds that the recorded fatalities were because of how the extracts affect parasites. To ascertain the effects of either natural or experimental haemonchosis in ruminants, it is advised to validate the efficacy of the plant’s extracts.
Introduction
Neem and Dogonyaro are both Hausa names for Azadirachta indica, an evergreen tree in the Meliaceae family of mahogany. It grows in tropical and semi-tropical areas and is indigenous to India, Pakistan, and Burma (Balakrishnan et al., 2007).
It is the most adaptable, diverse tree in the tropics, reaching a height of about 25 meters, with a semi-straight to straight trunk, a girth of 3 meters, and spreading branches forming a broad crown (Kumar and Gupta,2002).
More than any other tree species, it has useful non-wood products (leaves, bark, flowers, fruits, seeds, gum, oil, and neem cake). These non-wood products are known to have biological properties such as spermicidal, insecticidal, larvicidal, nematocidal, anti-inflammatory, anti-pyorrhoeic, anti-scabic, and cardiac (Brahmachari,2004). Neem’s expanded uses and activities have
created a green treasure (Khanna, 1992,Suri and Mehrotra 1994).
The tree is able to adapt to a variety of climatic, topographic, and edaphic factors. It does well in shallow soils that are dry, stony, and even hard calcareous soils or clay pan (Koul et al.,1990,Schmutterer, 1990).
Neem trees need lots of sunlight and little water (Anonymous,2006, Sateesh,1998). The tree naturally grows in regions with rainfall between 450 and 1200 mm. But it has been implemented with success even in regions with rainfall as low as 150 to 250 mm. It can grow at elevations of up to 1500 m. (Chari, 1996, Jattan et al., 1995, Tewari, 1992).