Macrorhabdus ornithogaster is a well-known cause of proventriculitis in birds. Although this organism was originally termed Megabacterium due to its large, rod-like appearance, the organism has since been classified as an anamorphic ascomycetous yeast. Clinical signs may be variable and include sudden death or chronic wasting. Diarrhea or enteritis has also been reported in birds colonized by Macrorhabdus; however, these birds can have concurrent enteric parasites, bacterial infections, or other diseases that could cause diarrhea.

Sparganosis is an infection of tissues by second stage larvae (spargana or plerocercoid) of pseudophyllidean tapeworms. Sparganosis due to pseudophyllidean cestodes such as Sparganum spp. (e.g. Sparganum proliferum) and Spirometra spp. (e.g. Spirometra mansonoides, Spirometra erinaceieuropaei) can occur in body cavities or in tissues of intermediate and paratenic hosts. Sparganum proliferum is phylogenetically identified as a new species in the order pseudophyllidea. The life cycle and the definitive host of Sparganum proliferum is unknown but believed to be similar to that of Spirometra spp. The definite hosts of Spirometra spp. are carnivores, and the eggs are shed in feces. The eggs embryonate in the environment, hatch in water and release coracidia. Coracidia are ingested by intermediate hosts, copepod crustaceans (Cyclops spp.), and develop into procercoids. Second intermediate hosts including fish, reptiles, and amphibians ingest infected copepods and acquire procercoid larvae. Procercoids develop into plerocercoids in the second intermediate hosts. Predators of the second intermediate hosts are infected by the plerocercoids. Plerocercoidosis/sparganosis develops after ingesting procercoids or plerocercoids with contaminated water or infected intermediate hosts. Humans and other mammals including apes, pigs, dogs, and cats can serve as paratenic or second intermediate hosts and develop sparganosis.

Two cases of mushroom toxicosis recently have been diagnosed at the TVDIL. The first case involved a 2 year-old mixed breed dog that died following a brief course of vomiting and bloody diarrhea. The second case involved a 12 week-old Labrador Retriever puppy with a history of vomiting with death occurring within 24 hours of the onset of clinical signs. The submitting veterinarian noted that the owners had seen the puppy eat a mushroom. Both dogs had submassive to massive hepatic necrosis which is very typical for mushroom poisoning.

Enterotoxemia, also known as overeating or pulpy kidney disease, is a condition caused by Clostridium perfringens type D. These bacteria are normally found in the soil and as part of the normal microflora in the gastrointestinal tract of healthy sheep and goats. Under specific conditions, these bacteria can rapidly reproduce in the animal’s intestine, producing large quantities of toxins. The epsilon toxin produced by C. perfringens Type D is the most significant toxin in producing the disease. Young animals are most susceptible. Sudden and high mortality rates may occasionally occur in lambs and kids. Although adult animals are also susceptible to enterotoxemia, they develop immunity due to frequent exposure to low doses of these toxins.

The importance of the veterinarian’s role in animal cruelty cases has recently been highlighted in the news media and numerous journals. In December, the AVMA endorsed a document called “Practical Guidance for the Effective Response by Veterinarians to Suspected Animal Cruelty, Abuse and Neglect” which is intended to aid veterinarians in establishing individual, practice-specific policies and procedures that best serve the needs of the animal, the client, the veterinarian and the community.

Kidney disease is a leading cause of illness and death in dogs and cats. Treatment of acute and chronic kidney disease is most effective when the disease is recognized early in its course and when treatment is instituted with knowledge of the underlying disease process. To aid in the diagnosis and treatment of kidney disease, the Athens Veterinary Diagnostic Laboratory is now offering renal diagnostic and treatment expertise through its newly established Renal Pathology Consultation Service.

Canine distemper virus (CDV) infects and causes disease in domestic dogs and many wild carnivores, including coyotes, ferrets, foxes, lions, mink, raccoons, and skunks. Although sustained vaccination of domestic dog populations has greatly reduced the incidence of canine distemper, the disease is still prevalent worldwide and now occurs in sporadic outbreaks. Young puppies between 3 and 6 months of age are more susceptible to infection and undergo more severe disease than adult dogs. However, non-vaccinated older dogs are also highly susceptible to infection and disease.

Many cedar waxwings were found dead in a yard in Thomas County, Georgia, in April, 2009. Five of these submitted to the Tifton Veterinary Diagnostic and Investigational Laboratory, where they were examined grossly and microscopically.

Veterinary pathologists are challenged daily with making a diagnosis on a variety of surgical biopsies. Many times clinicians will opt for surgical biopsy hoping for a definitive diagnosis that will give relevant information for therapy and prognosis. The pathologist becomes that one person from whom clinicians and owners wait for an answer. At times, however, the histological findings are inconclusive. Some examples of challenging diagnoses are discussed below.