"Look Beyond Chemicals": An alternative Approach to Control Fly Nuisance in Poultry Farms

Fly problem is an important concern internationally wherever poultry farming is an important economic activity. House flies are the most persistent and common pest, although other species such as blow flies and little house flies are present. Housefly is a major domestic, medical, and veterinary pest that causes irritation, spoils food, and acts as a vector for many pathogenic organisms. These flies act as a vector to various disease causing organisms and thus possess a great threat to human and confined poultry health. Musca spp. can prosper in wide range of environmental conditions with high reproductive rate and can breed throughout the year. Fly control is still an important public health measure in the 21st century.

The house fly control is largely based upon the use of chemical insecticides such as organ chlorines, organophosphates, pyrethroids. However, use of chemical insecticide is not only detrimental to environment and have undesirable effects on non-target organisms, but its long term use also leads to development of resistance among insects (Thomas and Jespersen, 1994). Injudicious use of these insecticides on large scale particularly in proximity to human food may prove to be toxic to man (Bhatia et al., 2006). In search of environment friendly and effective insecticides, essential oils from plants could be a good approach (Kant and Bhatt, 1994). Presently, bioinsecticides, especially those derived from plant origin, have been increasingly evaluated in controlling insects. Flavonoids, Alkaloids, Saponins, Sesquiterpenes, Limonoids, Phenols, Stilbenes and Coumarins of plant origin have been reported to possess toxic, growth regulating and anti-feedant effects against a host of insect pests (Sunita and Lalijee, 2008). Therefore, considering the detrimental effects of chemical fly repellents and insecticides on the environment and human health the present study was undertaken to evaluate acaricide efficacy of herbal Fly repellent product (Keetguard liquid). The product comprises of oil of herbs viz. Eucalypta globulus, Cedrus deodara, Pinus longifolia & many others in a fixed concentration.

 A efficacy evaluation trial of product Keetguard was  conducted in a farm near village Yewat, Dist. Pune having huge fly population. The environmental temperature and relative humidity at farm premises was recorded during the period of experiment between 26.6-30.8^oC and humidity between 45-67 per cent. At this farm, three layer sheds caged with 10 thousand layer birds placed wide apart (100 feet) from each other with sufficient quantity of fresh manure underneath and having approximately identical fly population were selected for the present study. The repellent were applied to the area under (dropping area) and around the sheds by using power spray so that the spray reaches to the side mesh and entrances and tested against Musca spp. on the droppings, mesh, grills, grass and other objects and places where these flies were flying freely in the area as shown in figure 1.

Figure 1.Thick layer of droppings accumulated under the shed which is an ideal breeding place for flies and Spraying of the repellent in area around the shed.

The three selected sheds were marked as three different groups for the study

Group I: Shed treated with Keetguard liquid @ 1:20

Group II:  Shed treated with Keetguard liquid @ 1:40

Group III:  Control group (Shed treated with plain water)

Selection of fly base/bait for : A day before starting actual experiment, a pilot trial was conducted to select a best fly base (viz. paper sheets, white gonies, grass sticks etc.) or bait (viz. coloured sugar, egg albumin baits, syrup-soap baits etc), its position (viz. vertical/horizontal/ hanging/ fixed etc.) and location (viz. under/ sides of the shed) around the shed to assess maximum fly population per unit area at three different timings at an interval of 3 hrs throughout a day. Finally, syrup-based baits were preferred and applied on 8 the plain papers / fly sheets. These fly sheets were hanged at the side mesh of each shed so as to get the maximum access to flies in the premises and those escaping – newly emerged imagoes. The method was adopted on the basis of preference by the flies.

 Preparation of test solution (Keetguard liquid) for spray:

The stock herbal preparation which is sticky, brownish-orange coloured liquid presented in 250 ml plastic bottle was first poured in a plastic jar containing 1 lit of clean water and mixed thoroughly with a clean wooden stick to ensure proper and complete mixing of the drug. Then such stock solution was used to prepare working / spray solution of desired concentration i.e. 1:20 and 1: 40 respectively.

Total 6 baited fly sheets (three on either side) were hanged around the shed and kept undisturbed for one hour to settle on the flies as shown in figure 2. The snap shots of all six fly sheets, hanged around each shed, and were taken after 1 hour of its application. Fresh fly sheets were applied and the procedure was repeated 1 hour before every observation. The observations were recorded upto 1 week after the treatment. The numbers of flies present on each sheet on day first of application were counted on the 15’’ screen of LCD monitor.

Figure 2.Fly sheets to assess the fly population per unit area before and after treatment.

Fly Repellent efficacy against adult Fly population: The results for the effect of compound on the population of flies after First application on day 1and upto 1 week was recorded. % reduction in fly population on day 1 was recorded to be 88.21 % in group I and 86.93 % in group II in contrast to only 6% reduction in untreated control group III. The repellency of Keetguard Liquid at both the concentrations were significantly higher high on the day of application particularly during first 4-6 hrs. At 5th day and at the week end (7th day) after application, the level of fly population was maintained at significantly lower level. This may be the result of the larvicidal effect of the formulation which was sprayed on the manure (on droppings of the birds) under the sheds. The larvae came in contact with the formulation might have failed either to moult or pupate. The batch of flies expected to be emerged during this phase failed to develop. Thus it finally resulted in lowering the fly population. However, the population of flies increased significantly (P>0.01) in Group III.

The larvicidal action of Keetguard Liquid : The larval population of the Musca spp. in the droppings was 21.50+1.57 and 24.33+2.16 before application of the test compound which was significantly (P<0.01) reduced to 2.0+0.37 and 8.33+0.92 at 24 hrs after treatment indicating 90.69 per cent and 65.76 per cent reduction in the population of larvae in the group-I and group-II respectively. However, in the control group, there is 15.7 % increase in the larval count after 24 hrs from 21.00+1.65 to 24.30+1.45. These results indicate that Keetguard Liquid has got larvicidal action at both concentrations but the effect is more pronounced in Group I at the concentration of 1:20.

From the study conducted it was concluded that the compound Keetguard liquid has got potential fly repellent and larvicidal activity. Better fly control can be achieved with 3 consecutive applications weekly. As a consequence of factors such as, strict environmental legislation, increased resistance of pest to synthetic pesticides, growing residue awareness among consumers, mounting industrial research and development cost of chemical insecticides, there has been shift towards the interest for the use of natural insecticides. The development of natural or biological ectoparasiticidal & fly repellant product such as Keetguard Liquid will help to decrease the negative effects of synthetic chemicals & it is a suitable natural option for organic system of farming.