Neospora Caninum is a different topic that most dog owners and breeders are completely unfamiliar with being that it is not a widely known diagnosis in our companions. What is it? It is a parasite detected by a serologic blood test for dogs that eat raw beef diets and who are experiencing various symptoms. Clinical signs in puppies six months of age or younger typically are a hindrear weakness, patellar restrictions, paralysis, muscle atrophy. In adult dogs, they range from ventricular tachycardia, seizures, hepatitis, dermatitis, to neurological symptoms such as ataxia and weakening hindquarters.
This protozoan parasite can be serious, and if left undetected, can cause injury to the heart as well as permanent paralysis. Additionally, Myocardial Infarction (MI) resulting in ventricular arrhythmia occurs in some infected dogs as well as Dyspnea or shortness of breath, vomiting, and diarrhea in those with the polysystemic disease (of or relating to more than one system.) Other issues, e.g., Retinitis or inflammation of the retina, and optic neuritis also can arise in some dogs. Also, common are ulcers, pneumonia, peritonitis, and hepatitis.
For those interested, The NCBI or National Center for Biotechnology Information has a case study involving a 7-week old Irish Wolfhound puppy who was diagnosed with Neospora Caninum infection. Read it here: "Treatment of canine pediatric Neospora caninum myositis following immunohistochemical identification of tachyzoites in muscle biopsies."
Fundamentally, the protozoan parasite is found in domestic animals called intermediate hosts such as cattle, sheep, goats, dogs but also wild animals such as deer, rabbits, coyotes, wolves and foxes. In bovines, it causes abortions. Transmission occurs from the intermediate host such as from cattle when the dog eats infected tissue. In turn, dogs are considered definitive hosts by shedding the parasitic cysts in their feces but also by transplacental infection by an infected bitch to her puppies. The cysts have what is described as impervious shells allowing for the cysts survival after the feces is gone and can be ingested again by another dog or a grazing animal, hence, toxoplasmosis.
Parenthetically, the Companion Animal Parasite Council (CAPC) reports that:
"Free-roaming dogs, dogs residing in the presence of cattle, and breeds such as Basset Hounds, Boxers, German Shorthaired Pointers, Golden Retrievers, Greyhounds, and Labrador Retrievers are more commonly seropositive."
Insofar as treatment, many Board Certified Neurologists recommend treating Neospora with either one or a combination of these protocols: 1- Clindamycin (4-week minimum) or 2- Trimethoprim sulfadiazine and pyrimethamine or 3- Clindamycin and Trimethoprim sulfadiazine.
Ballyhara Irish Wolfhounds have been naturally-reared for over 20 years, and approximately seven years past, I had a wolfhound diagnosed with Ventricular Premature Contractions. My Board Certified Cardiologist immediately performed two tests. The first was a Cardiac Troponins test for Myocardial Infarction (MI) and the second, a Neosporosis Caninum serologic test looking for the presence of the protozoan parasite. Interestingly, the serologic test results came back at a 1:100; titers with levels greater than 100 indicating probable exposure. After researching the recommended drug protocols, we proceeded with a Clindamycin treatment for an extended period (at least four weeks.) After which we retested, and his titer level came back below 100. This wolfhound never demonstrated any indications of paralysis or weakening.
I was and remain unwilling to use either #2 or #3 combinations of the above-described protocols as there are many concerning adverse effects of the sulfa drug. Still, depending on the titer result, if a very high titer or a dog presenting symptoms were involved then a typical recommendation would be to use the #3 protocol, especially if the dog had a rising titer. Notably, costs for the serologic examination will depend on what area of the country one lives. Texas A&M is the gold standard testing facility for Neospora and my costs, including shipping were $165.00, per test.
Approximately three years past, I had another Wolfhound diagnosed with Ventricular Premature Contractions and whom we also tested for Canine Neospora serum antibodies. Her titer results were higher at 1:400, and as a result, we followed the standard Clindamycin protocol. After four weeks, we retested again and saw a decrease in the titer level.
As recent as one year past, we tested a Veteran Wolfhound for Neospora after I brought him to a Neurologist for consultation on a cervical spine injury with subsequent ataxia radiating down the spine. His serum antibody titer was 1:400. Disturbed, we randomly tested two other veteran Wolfhounds at home, and they both were negative. This time, we did not treat the supposedly affected hound with Clindamycin, and after four weeks, we retested him, and his test results came back at 1:200, lower than the first.
The conclusion of my Specialist was manifold:
1. the first sample indicated previous exposure OR false positive and NOT a true active infection.
2. Danny did not need Clindamycin or TMP-SMZ
3. His neurologic signs are NOT from Neospora, but it may have been in the food that he ate at some point in the past.
I should note here that the NCBI article I prefaced earlier states that
"Definitive diagnosis of neosporosis requires identification of organisms in a muscle or CNS biopsy, using immunohistochemical (IHC) staining."
Essentially, a biopsy of a muscle from the patient is the best procedure to diagnose but also requires a special stain kit. Keep in mind that a muscle biopsy requires anesthesia, and the stain kit is an additional expense usually around $400 in addition to the normal biopsy fee. All told, the costs can add up.
In conclusion, I previously and successfully used the clindamycin protocol to treat Neospora. Still, it remains a mystery how one wolfhound in our pack was seropositive, and others were seronegative. On occasion, there are false positives or dormant infections that a titer may detect, as well as individuals may have different immune responses to the same organism. Although I am not a scientist, I have pondered what may be a possible explanation being that dogs who are naturally-reared and who consume raw beef will naturally have higher titers for the parasite due to exposure but not an infection. I base my hypothesis on the argument that W. Jean Dodds, DVM, and Diana Laverdure present in their book, "Canine Nutrigenomics, The New Science Of Feeding Your Dog For Optimum Health." They state that laboratories have developed their normal ranges based on dogs fed cereal grain foods, but the normal ranges for many of these tests simply do not apply for healthy dogs fed raw diets, and the interpretation of laboratory results for these dogs should take these differences into account. The authors explain that dogs fed raw diets exhibit naturally higher levels, e.g., BUN levels. So, perhaps the serologic test for Neospora is similar?
It is a vexing issue, and although there are cases available, I have found contradictory data on how best to prevent it. Let us set aside the typical reactionary response "Don't feed raw meat" and my sarcastic retort "My goodness, how did dogs ever develop and prosper over thousands of years without the aid of 20th-century dog food and its manufacturing operations based on corporate bottom line?" There seems to be an unfounded solution repeated by many that freezing the meat for 24-hours, before defrosting and feeding, will kill the parasitic cysts. On the contrary, I ascertained that beef meat must be frozen for at least two to three weeks to kill most parasites and incidentally, this also is recommended in the book mentioned above where Dodds states to freeze meats for at least three weeks to kill most parasites. One other solution that I am investigating is Food Grade Diatomaceous Earth which has long been touted as a natural dewormer. Though different, I will keep you updated on what I find.
There you have it -- if and when I have more information I will report it. Hopefully, for that person surfing the Internet in search of information on this topic, you will have found this somewhat helpful...