Surreal digital illustration of a horse silhouette filled with swirling patterns of medical data, representing SAA levels.

Decoding Colic: Is Serum Amyloid A the Key to Post-Operative Success in Horses?

Nico Varela in Health & Wellness November 2025 • 4 min read.

"Unraveling the complexities of post-operative complications in colic horses through serum amyloid A (SAA) analysis."

Colic surgery is a major intervention for horses, but the recovery period can be fraught with complications, including surgical site infections, colitis, and other issues. Identifying these complications early is crucial for improving outcomes, but traditional methods aren't always reliable.

One promising area of research involves acute phase proteins, which are released by the body in response to inflammation. Serum amyloid A (SAA) is a major acute phase protein in horses, and it's been investigated as a potential marker for various inflammatory conditions. Could SAA levels help us better predict and manage post-operative complications in colic horses?

A new study dives deep into this question, analyzing SAA concentrations in horses undergoing colic surgery and exploring its relationship with post-operative complications and infection. Let's break down the key findings and what they could mean for equine care.

SAA Levels After Colic Surgery: What the Research Reveals

Surreal digital illustration of a horse silhouette filled with swirling patterns of medical data, representing SAA levels.

The study, published in Veterinary Surgery, tracked 51 horses undergoing colic surgery. Researchers collected blood samples to measure SAA and fibrinogen concentrations, as well as neutrophil counts, at various points: pre-surgery, and on days 1, 2, 4-6, and at discharge.

The results showed that SAA levels generally increased significantly after surgery in all horses, indicating a strong inflammatory response. However, the key question was whether SAA levels could distinguish between horses with and without complications.

SAA and Post-Operative Colic: Elevated SAA levels on days 2 and 4-6 were associated with post-operative colic.
SAA and Diarrhea: Similar to PO colic, elevated SAA levels on days 2 and 4-6 were also associated with diarrhea.
SAA and IV Catheter Complications: Day 2 SAA levels showed an association with intravenous catheter complications.
SAA and Surgical Site Infections (SSI): Discharge SAA concentration was associated with SSI.
Fibrinogen's Role: Fibrinogen concentrations at days 4-6 and at discharge were associated with PO colic, diarrhea, IVC complications, and PO reflux.

Interestingly, the study didn't find a significant difference in SAA levels between horses with infections and those with non-infectious complications. This suggests that the overall inflammatory response to colic surgery might mask the specific signal of infection, at least in the early post-operative period.

What This Means for Horse Owners and Vets

While SAA might not be a perfect predictor of infection in the early post-operative period, it can still offer valuable insights. The study highlights the significant inflammatory response associated with colic surgery itself. Moreover, measuring SAA at discharge may help identify horses at higher risk of developing surgical site infections later on. Further research is needed to refine how SAA is used in conjunction with other diagnostic tools to optimize post-operative care for colic horses.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1111/vsu.13133, Alternate LINK

Title: Serum Amyloid A Concentration In Postoperative Colic Horses And Its Association With Postoperative Complications

Subject: General Veterinary

Journal: Veterinary Surgery

Publisher: Wiley

Authors: Maia R. Aitken, Darko Stefanovski, Louise L. Southwood

Published: 2018-11-29

Everything You Need To Know

What is Serum Amyloid A (SAA) and how is it relevant to horses recovering from colic surgery?

Serum Amyloid A (SAA) is a major acute phase protein that horses release in response to inflammation. Research suggests that tracking SAA concentrations post-colic surgery can help vets identify horses at higher risk of post-operative complications and surgical site infections.

According to the study, what specific post-operative complications in horses are associated with elevated Serum Amyloid A (SAA) levels?

Research indicates that elevated Serum Amyloid A (SAA) levels on post-operative days 2 and 4-6 were associated with post-operative colic and diarrhea. Additionally, SAA levels on day 2 were linked to intravenous catheter complications, while Serum Amyloid A (SAA) concentration at discharge was associated with surgical site infections (SSI).

Besides Serum Amyloid A (SAA), what role does fibrinogen play in predicting post-operative complications after colic surgery in horses?

Fibrinogen concentrations measured on days 4-6 and at discharge showed associations with post-operative colic, diarrhea, intravenous catheter complications, and post-operative reflux. This suggests that monitoring fibrinogen alongside Serum Amyloid A (SAA) could provide a more comprehensive picture of a horse's post-operative condition.

Why did the study not find a significant difference in Serum Amyloid A (SAA) levels between horses with infections and those with non-infectious complications after colic surgery?

The research did not find a significant difference in Serum Amyloid A (SAA) levels between horses with infections and those with non-infectious complications. This suggests that the general inflammatory response to colic surgery itself could overshadow the specific signals indicating an infection, particularly in the early post-operative stages. The study indicates measuring Serum Amyloid A (SAA) at discharge may help identify horses at higher risk of developing surgical site infections later on.

What are the limitations of using Serum Amyloid A (SAA) alone to assess post-operative complications in horses, and what further research could be beneficial?

While Serum Amyloid A (SAA) levels provide valuable insights into post-operative inflammation and potential complications like surgical site infections (SSI), it's important to note that the study didn't focus on long-term outcomes or explore specific interventions based on SAA levels. Further research could investigate how targeted treatments based on Serum Amyloid A (SAA) levels impact recovery times, long-term health, and overall survival rates in horses following colic surgery. Additional studies may also explore the use of Serum Amyloid A (SAA) in combination with other diagnostic markers to improve the accuracy of complication prediction.