AMPHISTOMES

                                          Introduction

• Amphistomes, commonly referred to as 'stomach' or 'rumen' flukes because of the localization of these flukes in the stomach of ruminants.

                                             Gross

• small size, pinkish color when fresh, pomegranate seed like
• Body is thick, conical,elongate with blunt ends.
• Ventral sucker is situated at the posterior end, large and strongly developed.
• Intestinal caeca coiled (3-4 coils) and terminate at about the level of middle of ventral sucker.
• Testes lobed and tandem.
• Genital sinus enclosing genital opening. The cuticle is spineless. The vitelline glands are lateral and are strongly developed.

                                           Location

• present in rumen, reticulum and sometime bile duct of liver also.

Host	Cattle, buffalo, sheep and goat
Location	Adults in Rumen and reticulum,Immature flukes in Duodenum
Intermediate host	Indoplanorbis,Gyraulus,Lymnaea and Bulinus

                                                                 life cycle

• Eggs are composite, distinct operculum
• Metacercaria is dark in colour and remains viable for 3 months
• Infection of definitive host is by the ingestion of metacercaria along with the grass herbage.
• The ingested metacercaria gets excysted in the small intestine and gets attached to the mucosa of duodenum as immature flukes.
• After 6-8 weeks the immature flukes starts migrating through various parts of intestine.
• I part of development Intestine – migrate -- Rumen/Reticulum.

                                                         Pathogenesis

• The immature flukes are highly responsible for causing the pathogenesis by their presence in the small intestine.
• The immature flukes attach very strongly and get embedded in the mucosa of the intestine and they are commonly called as plug feeder.
• These immature flukes eats away pieces of mucosa through the sucker and pinch them off resulting in necrosis and severe hemorrhage in heavy infections the deeply placed immature flukes may reach the muscular coat of the intestine causing hemorrhagic duodenitis
• The adult flukes are normally non-pathogenic and are seen attached to the rumen feeding only on the seminal papillae resulting in loss of ruminal papillae.
• Due to the presence of the immature flukes in the intestine, extensive catarrhal hemorrhage occurs in the duodenum and jejunum with degeneration of intestinal glands. There will be anaemia, hypoproteinaemia,oedema and emaciation.

                                            Clinical signs and symptomes

• Infected animals are weak emaciated showing proper foetid foul smelling diarrhea along with immature flukes present in faces.
• Death may occur within 15-20 days after the onset of clinical symptom.
• Incase of immature amphistomosis the rate may go up to 80-90 %
• Affected animals feel thirsty and drink water frequently, the animal also shows in bottle jaw ( intermandibular swelling)which is characteristic of flukes infection.
• The immature amphistomes is  called  in Hindi as “gillor”, “pitto”
• PM lesions mucous membrane looks pale, subcutaneous fat is replaced by a gelatinous material, hydrothorax, hydro pericardium, and hemorrhagic deodenitis.
• The immature flukes are seen attached to duodenal mucosa in clusters which appear pink is colour.

                                                     
                                              Diagnosis

• By clinical signs and symptomes- as mentioned above
• By faecal examination- idetification of eggs
• Presence of snail Intermediate host near to infected animals.
• sometimes Immature flukes also passed in diahorrheal feaces of infected animals
• by Postmortem examination -finding of flukes in the rumen, reticulum and bileduct of liver.

                                                         Egg characteristics

• Conical to oval shape, white to transparent, embryonic mass distinct and have operculum on both anterior and posterior ends.

Amphistome eggs