Chapter 1

Chapter 1

INTRODUCTION

Bangladesh is an agricultural country and its economic backbone is mainly based on agriculture. Agriculture plays a vital role in national economy, contributing about 16.33% of Gross Domestic Products (GDP) (Bangladesh Economic Review, 2014). Livestock being one of the major components of agriculture (crop, livestock, fisheries and forestry). The current contribution of livestock sub-sector to overall GDP is about 1.78% (Bangladesh Economic Review, 2014). The export earnings from leather and leather goods is 3.21% of the total export, 20% of the population is directly and 50% is partly dependent on this sector (Bangladesh Economic Review, 2014). Goat was the first ruminant livestock that was domesticated around 8000-11000BC (Luikart et al., 2006; Tapio et al., 2006). Among the domestic animals valuable to men in the tropics, the goat is perhaps the most important species. The largest number of goats is observed in Asia, followed by Africa, representing about 59.7% and 33.8%, summing up to 93.5% out of the total number of the world, respectively (FAOSTAT, 2012). Bangladesh possesses 25.611 million heads of goat (Bangladesh Economic Review, 2014).

The goats are mostly reared for meat purpose. Goats are very important group of livestock in Bangladesh. It is known to all that the main product of goat is meat and wool (Amin, 1994). Goats available in Bangladesh are of indigenous type having small body size and producing hairy and course wool of varied colors. In our country, the goat is primarily raised for meat and no attention is given for wool production. Goat is much more resistant to rain and other environmental hazard than other livestock animal. In rural areas of Bangladesh, most of the families rear goat or goat for their economic consideration. The meat of goat and goat has high demand in market and the milk of them is easily digestible. Their dung is used as Agro fertilizer; hides, skin and wool is considered as a source of earning foreign currency. Among the problems existing in Bangladesh hampering the livestock development, parasitic diseases occupy prime position in Bangladesh. Asian development bank estimated (1984) that the losses of animal production due to parasitic diseases were 50% in Bangladesh.

Bangladesh leathers have good inherent quality because of warmer climatic condition and food habits. Leathers made from hides and skins of animals maintained in warmer climates are superior to those of animals raised in colder climates, but such advantages are overshadowed by various defects (FAO, 2004). Surprising leather defects due to skin disease, postmortem defects or curing defects and industrial processing defects cut about 55.2% value of leathers resulting in annual economic loss of approximately Taka 818 core (US$ 220.95 million). Among such economic looses, US$ 24.1 million was due to Black Bengal goats skin defects in Bangladesh (FAO, 2004).

Today, societal and scientific concerns regarding exclusive dependency on chemicals have emphasized the need for the development and introduction of cheap and environment-friendly pesticide alternatives. In a recent study conducted by animal scientists from the University of the Philippines at Los Baos (UPLB), eight medicinal plants were tested for their efficacy in controlling ectoparasites in poultry and selected ruminants namely: carabao, goat, sheep, cattle, and dog. The selected botanicals were: leaves of kakawate (Gliricidia sepium), akapulko (Cassia alata), neem (Azadirachta indica), calabash (Crescentia cujete), alagaw (Premna odorata), tobacco (Nicotiana tabacum), stems of makabuhay (Tinospora rumphii), leaves of kutchai (Allium tuberosum), and roots of tubli (Derris philippinensis). The plant parts were prepared either as a 100% crude powder and applied topically to the whole body of the animal or as a decoction or crude water extract in various concentrations. The decoction used oil or water as a carrier and it was applied on the test animals as a spray, dip, sponge bath, or as a "pour-on" application.

Most of the farmers in Bangladesh cannot afford to buy modern medicine for the treatment of the livestock because of high price of the drug and poor economic condition of the farmers. So, if we can develop the traditional system of medicine in Bangladesh it will be highly beneficial for the farmers and for the overall improvement of the livestock. Recently much interest in the field of medicinal plants has been grown throughout the world. Many countries have already come to realize the medicinal plants as a potential means of therapeutic agent and also their availability and cost effectiveness.

In Bangladesh many drugs are being used for long time to combat parasitic infection in livestock. A large number of anthelmintics are now available in the market. The indiscriminate use of anthelmintics made the parasites to be resistant against the drug, which have been reported by experts throughout the world including Bangladesh (Hannan, et al., 2001). So, we should have to back the traditional uses of medicines.

Ectoparasites are distributed all over the world but occur mainly in tropical and sub-tropical countries including Bangladesh. Ectoparasites result in a considerable amount of blood loss, disturbances in feeding, retarded growth and decreased production. The damages caused by ticks are irritation, inflammation, exudation of lymph which coagulates to form crusts. Ectoparasites like ticks play an important role as vector of deadly pathogens to animals and man. Mites cause dermatitis, alopecia and sometimes animals are infected secondarily by bacteria causing toxemia, septicemia and ultimately dead of the animals. Among the ectoparasiticides, Ivermectin, a new patent drug, this is effective against both endo and ecto parasites and skin lesions of animals available in Bangladesh. Ivermectin stimulates the release of GABA from nerve ending and enhance binding of GABA to special receptors at nerve junctions.

Various types of herbal extracts showed the larvicidal and acaricidal effects (Chungsamarnyart,et al. 1991). In fact, the preliminary study on the traditional system of Veterinary Medicine by Food and Agriculture Organization (FAO, 1980), revealed that indigenous system for the treatment of animal diseases is popular in man in Asian countries including Bangladesh. There are several indigenous medicinal plants (neem oil, Tobacco) have anthelmintics action (Nath, 1983, Mostofa, 1983 and Hossain, 1994) and used against both ecto and endo parasites in Bangladesh, (Mostofa, 1983, Safique 1983, Mannan, 1997). Neem has been used historically to rid the body of several forms of ectoparasites and pests and the action is rapid. Hormone mimicking activities of neem extracts causes interference with the parasitic life cycle inhibiting their ability to feed as well as prevent the hatching of eggs (Kumar and Navaratnam, 2013). Neem plant contents have been reported to be an effective bioinsecticide (Chary, 2011) and found useful in the control of many insect species of medical and veterinary importance. Research work in this field is tilled now limited in our country.

At present there are no available effective drugs without toxicities. Although ivermectin is safe and effective against both ecto and endo parasites of animals but it is expensive. In contrast, the alternative cheapest and available source of drug is herbal therapy. Experimental investigations, therefore, is imperative to assess the therapeutic value of indigenous herbal plants and oil. From this point of view, this research work has been designed to investigate the comparative efficacy of indigenous medicinal plants (tobacco and neem oil) and ivermectin against ectoparasites (ticks) of goats with their adverse effects, if any. Therefore, the research work was undertaken with the following objectives:

i. To investigate the efficacy of indigenous medicinal plant (Neem oil, Tobacco and their combined) and Ivermectin against ectoparasites (ticks) in goats.

ii. To study the adverse effects of indigenous medicinal plant (Neem oil, Tobacco and their combined) and Ivermectin against ectoparasites (ticks) in goats.

iii. To study the effects of indigenous medicinal plant (Neem oil, Tobacco and their combined) and Ivermectin on some hematological parameters against ectoparasites (ticks) in goats.

Chapter 2

Review of Literature

The main purpose of this chapter is to get up-to-date information regarding the research works addressed here. Important information related to the present study was represented below. The contributions made by numerous research workers are compiled and the publications are documented in the references.

2.1 Effects of Tobacco against ectoparasitesTobacco leaves contain more than 3.5% nicotine. They are widely distributed throughout the world, mainly cultivates in Indonesia, Japan, China, India, Pakistan, Afghanistan and Bangladesh. It originates in Argentina. Maximum tobacco cultivate in America and their tobacco is best quality. Its main component is nicotine (Nicotina tabacum) an alkaloid which is soluble in water and has an antiparasitic activity. Once it was used as a drug to treat the ulcer and headaches. Leaves and stems are used as a strong narcotics. Its extracted nicotine is used as insecticides. Nicotine acts as an active anthelmintics.

Fajimi et al. (2012) Studied on the anti-louse activity of aqueous tobacco extract in heavily parasitized West African dwarf goats. The goats were allotted into three treatment groups of six animals each, viz: ivermectin treatment (subcutaneous injection of 0.5mg/kg bodyweight ivermectin); tobacco extract treatment (topical application of undiluted tobacco juice) and the untreated control. The assessment of depth of infestation and cure was based on the geometric mean of the louse counts. The geometric mean louse count decreased from 1690.71 to 2.62 (99.84% efficacy) by day 14 in ivermectin treatment; while it decreased from 1627.39 to 0 (100% efficacy) in the tobacco extract treatment. The geometric mean louse counts continued to increase in the untreated control group. There were increases in live weight gains in the ivermectin and tobacco treated groups against the corresponding loss in weight recorded in the untreated control. At 78 days post-challenge employing two louse-infested goats, significant louse count could not be registered in the tobacco-treated goats.Aktar (2007) carried out an experiment to study the comparative efficacy of ivermectin neem and tobacco. Thirty sheep of both sexes and aged upto 3 to 5 years infested with ticks and lice were randomly divided into 6 equal groups. Group A kept as infested control group. In group B, the efficacy of Invemectin (200 (g/kg, body weight) is 100% against ticks and lice after 7 days of treatment. In group C and D, the efficacy of neem at 1% concentration is 56.25% and 63.71% against ticks and lice respectively but at 2% concentration the efficacy is 64% and 71.73% against ticks and lice respectively. In group E and F, the efficacy of tobacco at 1% concentration is 60% and 65% against ticks and lice respectively but at 2% concentration the efficacy against ticks and lice are 68.96% and 74.46% respectively. Both neem and tobacco at 2% concentration shows higher efficacy than at 1% concentration against ticks and lice. Tobacco shows higher efficacy than neem in both 1% and 2% concentration against ticks and lice. TEC and Hb and PCV level increased at 21st (p