Introduction
Gastrointestinal (GI) issues in pets can manifest as a variety of symptoms, including vomiting, diarrhoea, weight loss, and abdominal pain. Gastroscopy and colonoscopy are two types of endoscopic procedures that allow veterinarians to view the inside of the stomach, intestines, and colon, helping diagnose and treat a variety of gastrointestinal conditions.
Though both procedures are used to examine different parts of the GI tract, they each play a unique role in diagnosing digestive disorders. Let’s dive into their history, differences, and when each is typically used in veterinary medicine.
A Brief History of GI Tract Endoscopy in Veterinary Medicine
🔬 Early Gastrointestinal Examinations (Pre-1900s): Before endoscopic procedures, veterinarians had to rely on radiographs (X-rays), exploratory surgery, and clinical signs to diagnose GI disorders. In the early years, diagnosing stomach, small intestine, or colon issues involved invasive techniques that could be risky for both the pet and the veterinary team.
📈 The Emergence of Endoscopy (1950s-1970s): The use of fibre-optic technology in humans revolutionized gastrointestinal endoscopy in the mid-20th century. By the 1960s, veterinary professionals began to adopt these technologies to examine animals’ digestive systems, initially using rigid scopes for procedures like gastroscopy and colonoscopy.
🚀 Advancements in Flexible Endoscopy (1990s-Present): With the development of flexible endoscopes, veterinarians could examine the entire gastrointestinal tract with much less invasiveness and discomfort for the animal. Video endoscopes allow for clearer imaging, while advancements in biopsy tools enable veterinarians to take tissue samples for laboratory testing.
What is Gastroscopy?
Purpose:
🔍 Gastroscopy is an endoscopic procedure that allows veterinarians to examine the stomach and the first part of the small intestine. It is especially useful in diagnosing conditions such as gastritis, ulcers, tumours, foreign body ingestion, and inflammatory bowel disease (IBD).
Procedure:
1️⃣ The pet is placed under general anaesthesia for safety and comfort.
2️⃣ A flexible endoscope (gastroscope) is inserted through the mouth, down the oesophagus, and into the stomach.
3️⃣ The camera at the tip of the scope provides real-time images, allowing the veterinarian to examine the stomach lining and other GI structures.
4️⃣ If necessary, biopsies or foreign body retrieval can be performed during the procedure.
Common Uses:
✔️ Diagnosing gastric ulcers or inflammation (gastritis)
✔️ Foreign body ingestion – Removal of objects such as toys, bones, or clothing.
✔️ Investigating chronic vomiting or unexplained weight loss
✔️ Identifying tumours or masses in the stomach
✔️ Biopsy collection for conditions like inflammatory bowel disease (IBD)
Limitations:
❌ Cannot reach the intestines beyond the stomach – For deeper GI issues, a colonoscopy or additional imaging may be necessary.
❌ Not effective for lower GI tract issues – It focuses exclusively on the upper GI tract.
What is Colonoscopy?
Purpose:
🔍 A colonoscopy allows veterinarians to examine the colon (large intestine) and rectum, which is essential for diagnosing conditions such as colitis, constipation, tumours, polyps, and inflammatory bowel disease (IBD) in the lower GI tract.
Procedure:
1️⃣ The pet is placed under general anaesthesia to ensure they remain still.
2️⃣ A flexible colonoscope is inserted through the rectum and advanced into the colon.
3️⃣ The camera provides real-time visuals of the colon walls, rectum, and terminal ileum (the last section of the small intestine).
4️⃣ Biopsy samples or foreign objects may be removed, and in some cases, polyps or tumours may be treated with special tools.
Common Uses:
✔️ Diagnosing colitis (inflammation of the colon)
✔️ Identifying tumours or growths in the colon or rectum
✔️ Chronic diarrhoea or constipation that is difficult to treat with standard therapies
✔️ Polyps or masses in the colon
✔️ Inflammatory bowel disease (IBD) – Confirming and monitoring conditions that affect the lower GI tract.
Limitations:
❌ Does not examine the upper GI tract – It cannot visualise the stomach or small intestine.
❌ Requires a clean colon – For the procedure to be effective, the colon must be emptied, which involves a pre-procedure fasting and laxative regimen.
| Feature | Gastroscopy 🩺 | Colonoscopy 🌿 |
| Examines | Stomach and Small Intestine | Colon & Rectum |
| Common Uses | Vomiting, ulcers, foreign bodies, tumours | Chronic diarrhoea, constipation, IBD, Polyps, tumours |
| Procedure Type | Insertion through the mouth | Insertion through the rectum |
| Procedure Complexity | Less invasive | More invasive, requires colon prep |
| Anaesthesia needed? | Yes | Yes |
| Biopsy Collection? | Yes for stomach conditions | Yes for colon/rectum conditions |
| Foreign Body Removal | Yes from the stomach | Not typically for foreign bodies |
| Post-Procedure Care | Minimal rest required | More invasive, and requires colon prep |
Which Procedure is Best for My Pet?
The choice between gastroscopy and colonoscopy depends on your pet’s symptoms and suspected condition:
✔️ If your pet has chronic vomiting, suspected foreign body ingestion, or gastric ulcers → Gastroscopy is the best option.
✔️ If your pet is experiencing chronic diarrhoea, constipation, or has suspected colon tumours or polyps → Colonoscopy is recommended.
✔️ If you’re unsure, your veterinarian may recommend both procedures to get a complete picture of your pet’s gastrointestinal health.
What to Expect After the Procedure
🏡 Same-Day Discharge: Most pets are able to go home on the same day as the procedure.
🍲 Post-Procedure Diet: Your pet may be given a bland diet for a day or two and should avoid eating anything that could irritate the stomach.
💊 Medications: Anti-inflammatory or pain medications may be prescribed based on findings from the procedure.
🩺 Follow-up appointments: If biopsies were taken, your vet will review the results and discuss treatment options within a week.
Final Thoughts
Gastroscopy and colonoscopy are crucial tools for diagnosing a wide range of gastrointestinal diseases in pets. They provide minimally invasive access to the digestive system, allowing veterinarians to visualise, diagnose, and sometimes treat conditions without the need for exploratory surgery.
If your pet is experiencing digestive issues, chronic vomiting, diarrhoea, or weight loss, talk to your veterinarian about whether gastroscopy or colonoscopy is the next step in diagnosing your pet’s condition.