📝 STANDARD DESCRIPTION:
Important Lymph Nodes (palpable / clinical):
1. Subiliac LN (= Prefemoral LN):
- Largest external LN of hindlimb.
- Located in front of thigh, in the fold of flank.
- EASILY PALPABLE in cattle.
- Drains: skin of thigh, abdominal wall, flank.
2. Popliteal LN:
- Behind stifle (in popliteal fossa).
- Drains: distal hindlimb (foot, leg).
- Palpable in dogs and large animals.
3. Superficial Inguinal LN:
- In groin region.
- In males: scrotal LN (drain scrotum & testis).
- In females: supramammary (mammary) LN (drain udder) — Very important in mastitis and udder cancer!
4. Deep Inguinal / Iliac LN: along iliac arteries; drain pelvic viscera & deep hindlimb.
5. Sacral / Internal Iliac LN: pelvic floor; drain rectum, vagina, bladder.
📚 DETAILED DESCRIPTION:
LYMPH NODES OF HINDLIMB & PELVIS
These nodes are routine examination points in clinical practice and at meat inspection.
1. SUBILIAC LYMPH NODE (Prefemoral / Lymphocentrum subiliacum):
• Position: Lies in the fold of the flank, just cranial to the thigh, embedded in fat.
• Easily palpated through the skin in cattle (the animal need not be restrained).
• Drainage area: Skin of thigh, abdominal wall, flank, and prepuce.
• Common site of enlargement in lymphoma (BLV in cattle), skin infections, and dermatitis.
• Always palpated during routine veterinary examination of cattle.
2. POPLITEAL LYMPH NODE (Lymphocentrum popliteum):
• Position: Caudal to stifle, embedded between biceps femoris and semitendinosus.
• Drainage: Distal hindlimb (leg, hock, foot).
• Palpable in dogs and cats; in cattle deeper.
• Enlarged in foot rot, distal limb infections.
3. SUPERFICIAL INGUINAL LYMPH NODES:
• In MALES: the scrotal lymph nodes — drain the scrotum and testis.
• In FEMALES: the supramammary (mammary) lymph nodes — lie above the back of the udder. Critical in:
– Mastitis (always check size & tenderness).
– Mammary tumours (cattle/dog) — first site of metastasis.
4. DEEP INGUINAL / ILIAC LYMPH NODES:
Lie along the iliac vessels inside the pelvic cavity. Drain the deep tissues of pelvis + hindlimb. Examined per-rectum in cattle/horse.
5. SACRAL / INTERNAL ILIAC LYMPH NODES:
On the pelvic floor near the rectum. Drain the rectum, vagina, uterus, urinary bladder.
6. ISCHIAL LYMPH NODE: On the lateral surface of the sacrosciatic ligament.
UG CLINICAL TIP — palpable LNs in cattle examination:
From front to back: parotid → submandibular → prescapular (superficial cervical) → SUBILIAC → SUPRAMAMMARY → POPLITEAL. Always check these in routine cattle exams (especially for tuberculosis, lymphoma, dermatitis).
// COMPARATIVE ANALYSIS
| CATTLE |
Subiliac and supramammary LNs are routinely examined. Persistent enlargement → lymphosarcoma (BLV). |
| DOG |
Popliteal & superficial inguinal LN are palpable in standard physical exam — enlargement = lymphoma. |
CLINICAL RELEVANCE
Mastitis: Always palpate the supramammary (mammary) lymph nodes — enlargement & pain confirm udder infection.
Bovine Lymphosarcoma (BLV): Generalized LN enlargement — subiliac and supramammary often the first noticed.
Foot Rot: Popliteal LN enlarged on the affected limb side.
