SU1001900A1 - Method of culturing horned cattle underskin gadfly stage larvae - Google Patents

Description

The invention relates to the 'area' of veterinary parasitology and can be used to test insecticides, obtain ymmuprepa- * j tov and diagnosticums.

A known method of cultivating larvae of subcutaneous gadfly in wet sand [1].

With this method, adult jq gadflies are grown without a nutrient medium.

A known method of culturing stage III larvae of Hypoderma lineatum in a nutrient medium [2], in which the larvae are removed from the nodules, placed in a narrow glass vessel containing 1/4 of the serum of animal rations. Blood serum is changed daily. Larvae survive for 10 days.

The disadvantages of this method are that the larvae, being in a vertical position, abut mouth holes in the bottom of the vessel, which * 6 complicates their nutrition. The lack of circulation of the nutrient medium and an insignificant amount necessitate the frequent replacement of it. The use of animal blood serum is very expensive, in addition, the latter is not sufficiently absorbed by the larvae.

The purpose of the invention is to obtain highly concentrated products of the vital activity of larvae in a nutrient medium.

The goal is achieved by the fact that the larvae of gadflies of the III stage of development are placed in a separate cell, covered with hydrophilic material on top and placed in a nutrient medium consisting of 3/4 parts of Ringer-Lock fluid, 1/4 of inactivated serum of cattle and antibiotics. Larvae are collected in April-May on carcasses and animal skins. Only gray-brown larvae are selected, so that during cultivation they could not go to the next stage of development.

During the cultivation of the larvae, conditions are created that are close to the animal’s body, for which they are placed in a cage with cells for each larva, they are covered with foam rubber on top, which prevents drying of the unloaded parts of the larvae. Antibiotics are added to the culture medium. A nutrient medium is circulated daily, which is changed after 7-10 days.

Example. Larvae of the III stage Hypoderma bovis and N. lineatum of gray-brown color are collected on animal skins and carcasses, washed with saline and placed in a cage for cultivation. Cage 5 is a quadrangular glass jar measuring 15'15 * 20 cm. Inside the jar, on a stand 12 cm from the bottom, a Plexiglas plate 14 × 13 cm in size is installed, which contains 48 cells. The cells are sawn from the bottom side so that there is free communication with the internal cavity of the can and that the larvae do not fall out (width 15 2 mm). On the upper side, the Plexiglas plate is coated with 8 mm thick foam rubber. Opposite each hole in the foam, a hole is made that at the base is equal to the diameter of the moon-20 ki (15 mm), and tapers to the apex conically and reaches 5 mm at the exit. A hole with a diameter of 15 mm is made in the center of the Plexiglas plate to insert the mixer shaft. Outside, the jar is covered with a lid, in the middle of which there is a square hole measuring 5 · 5 mm, sealed with a nylon mesh. It is necessary for free access jq air.

A nutrient medium is poured into the cage (4 parts of Ringer-Locke fluid, one part of inactivated blood serum taken from healthy cattle and 25 thousand units of ³ streptomycin and penicillin per 100 ml of medium) until the plexiglass plate is hidden .

A cage with larvae was placed in a thermostat at 31 ° C and a relative humidity of 40%. Periodically daily for 7 days, remove the jar from the thermostat, remove the lid and foam, insert the flexible shaft of the mixer into the hole and mix the nutrient medium for 5 min at 700 rpm. At the same time monitor the state of the larvae. The dead are thrown out, in their place are placed new ones, which are taken from the spare cage. After 50 days, the nutrient medium is changed. Used nutrient media and part of the larvae are used for the manufacture of an immunologic preparation. After 14-18, even 28 days, the remainder of the mask is transferred to the ground, where it is buried to a depth of 3-5 cm. There they pupate, and after 16-24 days adult gadflies appear. The proposed method for cultivating larvae of hypodermic gadfly cattle allows simultaneously with the cultivation of adult gadfly individuals to obtain vital products (nutrient medium) for the preparation of an immunopreparation. The application of the method allows the cultivation of larvae under conditions close to the animal’s body, which reduces the amount used by three times serum of cattle, increases the life expectancy of larvae from 10 to 28 days.

Claims (3)

Claim 1. A method of culturing stage III larvae of subcutaneous cattle gadfly, including collecting larvae, cultivating them in a nutrient medium from cattle blood serum, characterized in that, in order to increase the yield of larvae, improve product quality! and increase labor productivity, the larva is placed in a separate cell, covered with a hydrophilic material on top and placed in a nutrient medium consisting of 3/4 parts of Ringer-Lock fluid, 1/4 of inactivated serum of cattle and antibiotics, 2. The method of pop. 1, characterized in that the nutrient medium is changed after 7-10 days. 3. The method of pop. 1, characterized in that daily produce a circulation of the nutrient medium ..