ICAR AIEEA PG 2024 - Veterinary Science

In brucellosis (e.g., Brucella abortus in cattle): necrotic placentitis with morocco-leather appearance of cotyledons is hallmark (A); chronic infections frequently manifest as hygromas (bursitis, especially precarpal) and arthritis/synovitis (B); Brucella can penetrate intact conjunctival or alimentary mucous membranes in humans causing undulant fever (C). Statement (D) is incorrect because brucellar abortions typically occur in the last trimester (second half, between months 6 and 9) when high erythritol concentrations accumulate in the fetal placenta. Thus, (A), (B), and (C) only are true.

Concentric button ulcers (diphtheritic necrotic plaques over lymphoid follicles in the cecum and colon) are pathognomonic lesions classically seen in two porcine diseases: Classical Swine Fever (Hog Cholera, caused by Pestivirus) and Chronic Intestinal Salmonellosis (caused by Salmonella enterica serovar Typhimurium or Choleraesuis). Thus, (A) and (C) only is correct.

A euryxenous parasite is one that has a broad host range and can infect many diverse species of host animals. Trypanosoma evansi (the causative agent of Surra) infects camels, horses, cattle, buffaloes, dogs, elephants, and many wild mammals. In contrast, Eimeria tenella, Theileria annulata, and Babesia bigemina are stenoxenous (highly host-specific).