Larvae of bactrim pills and G. nigricornis, migrating in summer and autumn along the skin of the cheeks, cause striped depilation and dermatitis. Wrinkles and ulcers appear on the lips. The death of the animal is possible due to progressive exhaustion, which often happens in the spring. They depend on the period of the disease. In the first period, a large number of larvae are found in the oral cavity.
The mucous membrane is inflamed, ulcerated. In the second period of the disease, the larvae are found in the stomach and duodenum. The mucous and muscular membranes are inflamed and ulcerated. Pathological changes are usually noticeable in places of accumulation of larvae. On the mucous membrane of the stomach, duodenum and rectum, from several tens to several hundred gadfly larvae are found, nested.
In such areas, crater-shaped ulcers with a depth and width of up to 4–5 mm are clearly distinguishable, into which gadfly larvae are immersed with their front end. With the accumulation of a large number of larvae, the mucous membrane resembles a sieve. In addition, it is edematous, hyperemic, dotted with small hemorrhages. The submucosa was also changed. It is hyperplastic with connective tissue elements, is in a state of interstitial myositis and sclerosis. Numerous ulcerations in the same places sometimes lead to keratinizing stomach cancer.
Set on the basis of a complex of studies. History is of great importance. Gastrophiles are oftenare found in horses that have been on pastures for a long time without skin care. By detecting eggs or shells of gastrofilus eggs on the skin of horses, it is possible to predict the intensity of infection of the animal by gadfly larvae. Visually, the larvae are found on the root of the tongue and on the walls of the pharynx (the Bayer wedge is used). In winter and early spring, animals are given carbon disulfide at a dose of 6 - 8 ml or chlorophos at a dose of 25 mg / kg, which causes the excretion of a certain number of gadfly larvae along with fecal masses.
The diagnosis of gastrophiles can be made by an allergic test. As an allergen, a sterile aqueous extract is taken from the bodies of gadfly larvae of the most common species. The study is carried out similarly to the technique of ophthalmomalleinization. This ophthalmic test gives a positive result in horses with more than 100 gadfly larvae in the digestive tract (V.I. Potemkin, 1943). The correctness of the reaction readings reaches 85%. The method of post-mortem diagnosis matters. When opening the corpses of dead animals, the degree of invasion and the species composition of the larvae are revealed.
The autopsy data make it possible to judge the possible invasion by gadfly larvae of other horses of this farm. It is possible to predict the infection of horses with larvae of trimethoprim gadflies in the summer-autumn period by finding their eggs on the hairline. Gadfly larvae can be detected visually when examining the oral cavity and pharynx. Gastrophilus larvae are highly resistant to many drugs. Before the use of organophosphorus compounds, there were no agents capable of killing larvae through the digestive tract or cuticle.
The resistance of larvae increases with age, which should be taken into account when delarvating horses. It is advisable to expel the larvae from the host organism before they harm the animal, i.e. in autumn or early winter, when the larvae are more sensitive to larvicides. Inside, animals are given chlorophos at a dose of 30 mg/kg in the form of a 5% aqueous solution. This drug can be given with a small amount of feed.
The larvae of the first stage, located in the mucous membrane of the cheeks and gums, are destroyed during the summer of gadflies by abundant irrigation of the oral cavity with a 2% aqueous solution of chlorophos, or a 1% aqueous emulsion of bactrim, or a 1.5% aqueous emulsion of lysol. Such irrigation of the oral cavity is carried out every 10 - 15 days, before the transfer of horses to winter stall maintenance. When larvae are found in the pharynx and on the root of the horse's tongue, the mucous membranes are irrigated with a 1% aqueous solution of chlorophos.
Against larvae parasitizing on the rectal mucosa, a 1% aqueous solution of trimethoprim is also used in a dose of 300-400 ml in the form of enemas or an oily solution of HCCH containing 0.2% of the gamma isomer is used, which is used to lubricate the larvae. When introduced into the stomach through a tube, the death of 100% of the larvae of gastric botflies in horses was observed from trolen at a dose of 90 mg/kg, from ruelen and amidophos at a dose of 48 mg/kg of animal weight.
It is also possible to irrigate grain forage or hay with a 5% solution of chlorophos at the rate of 1 kg of feed per animal. Efficacy of moxidectin 2% gel for gastrophilia in horses. Moxidectin is a drug against endoparasites in horses, in particular Gastrophilus larvae. Moxidectin in the form of a 2% gel at a dose of 0.4 mg/kg for oral administration to horses (equest) belongs to anthelmintics, a group of macrocyclic lactones.
Due to the chemical structure of moxidectin, it dissolves well in fats, this property leads to a prolongation of its action by deposition in adipose tissue. In this it differs from other drugs in this group, such as abamectin, ivermectin and doramectin. The drug has 90% efficacy of mexedactin gel against G. intestinalis larvae and 100% efficacy against G. nosales.
In the days of the mass summer, horse gadflies are kept indoors and graze only at night. G. intestinalis eggs are scraped off the hair shafts with a sharp knife blade, thin glass, or fine sandpaper once a week during the gadfly season. The larvae hatched from the eggs are destroyed by irrigation of the horse's coat with a 1% aqueous solution of chlorophos or trichlormetaphos-3 every seven days.
During the summer period, gadflies make a planned change of bactrim: every 30 days, horses are transferred to new pastures, 10–12 km away from the boundaries of the abandoned pasture. The horses are returned to their previous pastures after two months.
Copyright © 2023 bactrim online