Assertion (A) is true: Sweeney (or slipped shoulder / loose shoulder) in horses and cattle is a condition where neurogenic atrophy of the shoulder muscles causes the shoulder joint to pop outwards (lateral subluxation / abduction of scapula away from the thoracic wall during weight bearing).
Reason (R) is false: Sweeney is caused specifically by trauma, compression, or stretching of the Suprascapular nerve as it crosses the cranial border of the scapular neck, causing denervation atrophy of the supraspinatus and infraspinatus muscles. Radial nerve paralysis causes dropped elbow, inability to extend carpus and digits, and knuckling, NOT sweeney.

In domestic animal anatomy, the femoral canal (canalis femoralis) is a fascial space situated on the medial aspect of the thigh bounded by the sartorius and gracilis muscles. Its primary contents include the femoral artery (A), femoral vein (B), the saphenous nerve (C, branch of femoral nerve), and deep inguinal lymph nodes/vessels (D). Hence, all four structures (A, B, C, and D) are contained within the femoral canal.

Option analysis:

• Incorrect because saphenous nerve is also an established content.
• Incorrect because deep inguinal lymph node is located in the femoral ring/canal.
• ((A), (B), (C) and (D)): Correct. All four are anatomical contents of the femoral canal.
• Incomplete.

In the pelvic limb of domestic ungulates, as the external iliac passes through the vascular lacuna to continue as the femoral artery, the proximal branch given off is the pudendoepigastric trunk (A) (or deep femoral origin), followed closely by the deep femoral artery (D), then more distally the anterior/cranial femoral artery (B), and finally near the middle/lower third of the thigh, the saphenous artery (C) arises before the femoral continues as the popliteal artery. Thus, the sequence from proximal to distal is (A), (D), (B), (C).

Option analysis:

• Incorrect order.
• Correct. (A), (D), (B), (C) represents the true proximodistal branching order.
• Inverts deep femoral and anterior femoral.
• Places saphenous too early.

In urogenital embryological development:

• Epoophoron: Vestigial remnant in females derived from cranial mesonephric (Wolffian) tubules (I).
• Paraoophoron: Vestigial remnant in females derived from caudal mesonephric tubules (II).
• Gartner's duct: Vestigial remnant of the main longitudinal mesonephric (Wolffian) duct in the female broad ligament and vagina (IV).
• Uterus masculinus (prostatic utricle): Remnant of the fused caudal ends of the paramesonephric (Mullerian) ducts in the male (III).