Veterinary Parasitology- ICAR JRF/SRF 2024

• Comparative Helminth Egg Dimensions in Swine:
• Strongyloides ransomi: Embryonated thin-shelled small eggs measuring approximately $45\text{--}55 \times 25\text{--}35\ \mu\text{m}$ (smallest).
• Ascaris suum: Oval, thick-shelled with a rough, mammillated albuminous coat measuring approximately $50\text{--}70 \times 40\text{--}50\ \mu\text{m}$.
• Macracanthorhynchus hirudinaceus: Thorny-headed worm egg with three protective embryonic layers measuring approximately $90\text{--}100 \times 50\text{--}56\ \mu\text{m}$.
• Fasciolopsis buski: Giant intestinal fluke operculated unembryonated eggs measuring approximately $130\text{--}140 \times 80\text{--}85\ \mu\text{m}$ (largest).
• Ascending Sequence: Sorting from smallest to largest yields (D) < (A) < (C) < (B) (Option 4).

Correct option: (4) (D), (A), (C), (B)

• Severity Classification in Haemonchosis: Because adult female Haemonchus contortus worms are exceedingly prolific (producing $5,000\text{--}10,000$ eggs per female per day), fecal egg counts (FEC) in sheep rise rapidly.
• Standard Diagnostic Tiers (Eggs Per Gram, EPG):
• Mild infection: $\lt 1,000$ EPG
• Moderate infection: $1,000\text{--}5,000$ EPG
• Severe / Heavy clinical haemonchosis: $\gt 8,000$ EPG (often exceeding $10,000\text{--}50,000$ EPG in acute outbreaks associated with severe anaemia, hypoproteinaemia, submandibular oedema, and sudden mortality).
• Clinical Application: Worm burdens exceeding 8,000 EPG correlate directly with severe haematocrit drops ($\lt 15\%$) and require immediate emergency anthelmintic intervention.

Correct option: (3) >8000

• International Standard Diagnostic Test: According to the World Organisation for Animal Health (WOAH, formerly OIE) Terrestrial Manual, the Complement Fixation Test (CFT) is the prescribed, gold-standard serological test for international trade health certification of Dourine (Trypanosoma equiperdum) in equines.
• Diagnostic Principles & Challenges:
• Dourine is a non-vector-borne, sexually transmitted trypanosomosis in horses and donkeys.
• Because parasitaemia is extremely low and transient, direct microscopic agent identification has very poor sensitivity.
• CFT displays high sensitivity for detecting chronic, subclinical carrier stallions and mares, although cross-reactions with Trypanosoma evansi can occur in endemic areas.

Correct option: (1) Complement fixation test