Veterinary Entomology

• Correct Matching Analysis:
• Cerebral cysticercosis / Gid: Caused by (II) Coenurus cerebralis (larva of Taenia multiceps) in the brain and spinal cord of sheep, producing circling movement (gid/staggers).
• Hepatic cysticercosis: Caused by (I) Cysticercus tenuicollis (larva of Taenia hydatigena), whose migrating oncospheres burrow through liver parenchyma producing hepatitis cysticercosa before attaching to the omentum and mesentery.
• Measly pork: Caused by (III) Cysticercus cellulosae (larva of Taenia solium) developing in striated skeletal and cardiac muscles of pigs.
• Measly beef: Caused by (IV) Cysticercus bovis (larva of Taenia saginata) residing in masseters, heart, and diaphragm of cattle.
• Summary: Matching yields (A)-(II), (B)-(I), (C)-(III), (D)-(IV) (Option 3).

Correct option: (3) (A) - (II), (B) - (I), (C) - (ill), (D) - (IV).

• Diagnostic Morphology: Members of the genus Trichostrongylus are minute, hair-like nematodes distinguished by a rudimentary (vestigial) buccal capsule lacking teeth or leaf-crowns, and a relatively short cylindrical oesophagus.
• Morphological Contrasts:
• Strongylus spp.: Possess an exceptionally large, sub-globular buccal cavity armed with external/internal leaf crowns and prominent basal teeth.
• Strongyloides spp.: Possess a long, cylindrical rhabditiform or filariform oesophagus occupying up to one-third of the total body length.
• Trichuris spp.: Possess a slender whip-like anterior portion enclosing an elongate stichosome oesophagus surrounded by a column of single stichocytes.

Correct option: (1) Trichostrongylus spp.

• Antimicrobial Constituents of Bovine Milk:
• Lactoferrin: Iron-binding glycoprotein that exerts bacteriostatic effects by sequestering free ferric ions ($Fe^{3+}$) required for bacterial growth.
• Lactoperoxidase: Combines with thiocyanate and $H_2O_2$ to generate antibacterial hypothiocyanite ($OSCN^-$).
• Secretory IgA (sIgA): Major mucosal immunoglobulin that neutralizes pathogens and blocks epithelial adherence.
• Somatic Leucocytes: Neutrophils, macrophages, and lymphocytes that phagocytose and destroy invading bacteria in the mammary gland.
• nalysis:
• All four components contribute to milk defense. Hence, Option 1 ((A), (B), (C) and (D)) is correct.

• Bacteria Shed Internally in Milk:
• Contamination of milk can arise from environmental exterior sources or directly from the interior of infected mammary tissue:
• Brucella abortus (B): Localizes chronically in supramammary lymph nodes and secretory parenchyma, shedding directly into milk.
• Salmonella Dublin (C): Systemic bacteremia leads to mammary colonization and direct internal excretion.
• Escherichia coli (A): Causes acute coliform mastitis within the glandular lumen.
• Streptococcus uberis / Staphylococcus (D): Established intramammary gland infections shed massive bacterial numbers.
• nalysis:
• All listed bacteria can originate from the interior of the udder. Hence, Option 3 is correct.