Mary Lou Gerace

If your dog is a finicky eater, isn’t able to gain or maintain a consistent weight and/or has intermittent loose stools over a period of time, yet seems healthy in all other ways, you may want to consider a form of SIBO (Small Intestinal Bacterial Overgrowth) as the culprit!  While SIBO is generally a chronic disease needing dietary management and continued medication support, my veterinarian indicated that they are now treating more and more cases of “intermittent diarrhea” and/or “loose stools” as they do SIBO. 

What is SIBO and what does it do to upset the bacterial balance in your dog?  When a dog has a small intestinal bacterial overgrowth, there is a dramatic increase in the number of “BAD” bacteria in the small intestine.  This can interfere with normal absorption of nutrients. The result is chronic, intermittent diarrhea and/or loose stools. Weight loss can also occur. 

Below is a chart that differentiates small intestine and large intestine diarrhea/loose stools:

CLINICAL SIGNS                SMALL INTESTINE                        LARGE INTESTINE

Frequency of defecation >        Normal or slight increased                     Very frequent

Fecal Volume   >                      Large quantity of bulky or watery          Small quantities often

Urgency >                                Absent                                                 Usually present

Tenesmus >                              Absent                                                 Usually present

Mucous in Feces >                   Usually absent                                      Frequent

Blood in Feces >                     Dark black (melana)                             Red (fresh)

Weight Loss >                          May be present                                    Rare

Unfortunately, there is no “best test” to confirm your dog has a small intestinal bacterial overgrowth and whether it is a true case of SIBO or just a bacterial imbalance.  A true SIBO condition may develop due to a complication of many other intestinal diseases and those diseases need to be dealt with individually.  With the more common “gut bacteria imbalance”, as I understand it, the bad bacteria takes over and the good bacteria can’t keep up!  In order for “gut” health, there must be a good balance between the bacterium. 

Depending on the severity of the symptoms (lack of appetite, loose stools, length of time of condition) most veterinarians will first do “elimination testing”.  They may test for parasites, bacterial infections, and partial obstructions and may look for other causes of the diarrhea/loose stools. Blood may also be drawn and tested.  If nothing conclusive is found, a conservative treatment approach is generally attempted prior to invasive testing for other, more significant intestinal disease.

Conservative treatment generally consists of antibiotics.  Whether your dog has a true case of SIBO or just a “gut bacteria imbalance”, it can usually be controlled with a course of antibiotics, and the antibiotic therapy may be repeated occasionally should a relapse occur. Tylosin (Tylan) is one of antibiotic usually prescribed.  In addition, dietary management using a therapeutic diet low in carbohydrates and fats may be prescribed.  IF continued reoccurrences are seen, this may indicate there IS a more serious unidentified underlying cause that will require further testing.  It may also indicate that permanent function mucosal damage has occurred.  Sometimes antibiotics gradually reduced to the lowest dose that will control the loose stools are needed for extended periods.  In addition, many veterinarians are now prescribing a “probiotic”  to be administered along with the antibiotic.  ‘Fastrack’ Microbial Supplement is just one of many probiotics on the market today.  It is a feed additive that provides a continuous supply of two effective and complementary lactic acid-producing bacteria, yeast, enzymes and probiotic fructooligosaccharides (FOS) to encourage maintenance of proper digestion and gut health. 

My youngest dog just went through the “gut bacterial imbalance” scenario.  Over a period of time, he became very finicky when it came to his meals and soon his stools, while not frequent, were loose.  When the loose stools really took hold, I attempted to treat him with the usual rice/hamburger combination.  It was obvious after 48 hours that I needed to get him in to see his vet!  After ruling out parasites, etc, he was put on a 2-week course of Tylosin (Tylan), and Hill’s Prescription i/d canned dog food.  We also started him on the Fastrack Probiotic.  Within a few days I saw improvement and I am pleased to report that he has been off the Tylan  for 2 weeks and all is well!  He is back on his kibble (Pinnacle) and eating like a Golden Retriever should eat….with GUSTO!!  I have kept him on a maintenance dose of Fastrack and his stools are “normal”.

As always, the above information is based on my personal research.  Please consult your vet.  Medical reference:  Merck Veterinary Manual and Rutgers , H.C. 1998. Diagnosis and long-term management of bacterial overgrowth in the dog.  ACVIM-Proceedings of the 16th Annual Vet. Med. Forum. pp. 482-484.

Until next time…. "A man's soul can be judged by the way he treats his dog."
                                                                                                                - Charles Doran

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