May 27, 2009
FROM THE DIAGNOSTIC LABORATORY
LABORATORY NEWS
The past few months have brought a flurry of activity to TVMDL. Although not directly involved in the novel H1N1 Influenza A outbreak, TVMDL has been busy, working with our industry partners as well as other State and Federal agencies, to provide support where needed. As part of the National Animal Health Laboratory Network, TVMDL is working closely with the National Veterinary Services Laboratories on the implementation of a swine surveillance program.
New Faces at TVMDL
Ms. Stacy Morris has joined the Directors office as the Executive Assistant to the Director. Stacy comes to us from the Texas AgriLife Extension Service where she worked at the V.G. Young Institute of County Government. Stacy has an extensive background in agriculture and earned her Bachelor’s and Master’s degrees from Texas A&M University.
Ms. Doris Tykal, previous Assistant to the Director at TVMDL, has accepted a new position within the TVMDL family. Doris will be the Human Resource Specialist for the TVMDL agency. Please join me in congratulating Doris on her new position. She will be missed in the Directors office.
Ms. Jean Dwyer has joined TVMDL as a Financial Analyst. Ms. Dwyer comes to us from a position with the Department of Homeland Security where she managed the DHS budgets at the Plum Island Animal Disease Center.
Construction and Renovation
Amarillo renovations and new BSL-3 laboratory: Design is well underway for renovating the sample receiving area and building a new BSL-3 laboratory in Amarillo. With several design meetings under our belt, we expect at construction on this facility to begin in late September/early October of 2009. These renovations will provide approximately 800 square feet of new BSL-3 space, a newly renovated sample receiving area and a new biosecure sample drop-off area for clients.
Gonzales: An architect has been selected and awarded the contract for construction of our new poultry facility in Gonzales, Texas. Dr. Sam Glas and his wife, Sally generously donated the land that this new facility will be located. Design on this facility is set to be completed by September 11, 2009 and construction is slated to begin in December 2009.
College Station: Renovations at College Station include the development of a new molecular suite. This new wing will allow for continued development of new diagnostic tools that will enable us to provide our clients with state-of-the art diagnostic capabilities.
New technology development: TVMDL is moving forward with purchasing a new laboratory information management (LIMS) system. This new system will allow for client information to be retrieved more quickly, for epidemiological data to be more easily accessible and complete, and for clients to have greater access to their accounts online. Additionally, clients will be able to electronically submit case forms online prior to their specimens arriving at TVMDL.
TVMDL has purchased new equipment that will allow a greater capacity for providing more specific, sensitive and accurate testing. The molecular section recently acquired a 16 capillary 3130xl DNA Analyzer. This equipment is the gold standard for high throughput genetic analysis. TVMDL will use this equipment for DNA fragment analysis applications such as viral and bacterial DNA sequencing as well as for molecular epidemiology. The availability of this sequencer will facilitate strain characterization and typing and at the same time, providing high quality data at a low cost per sample.
After the identification of H1N1 influenza 2009 in Canadian pigs, we adapted a PCR that can detect and subtype swine influenza H1N1, H2N2 and H3N2 viruses. This technology will facilitate the rapid identification of infected herds, which will allow a rapid response.
The serology section at TVMDL is in the process of installing a liquid handling robot system TECAN Freedom EVO. This equipment brings precision, reliable liquid handling and easy-to-use robotics. This system will facilitate high throughput serological testing in the laboratory.
We have installed and certified six new biosafety cabinets for virology, tissue culture serology and molecular diagnostics. This new equipment will ensure safely handling of samples under sterile conditions in order to provide high quality results.
New Look for the TVMDL Webpage
If you haven’t visited the TVMDL website lately, go to http://tvmdl.tamu.edu/. Numerous improvements have been made to the website. In addition to the new look, the website has been made more user-friendly. The home page now features a “spotlight” section which highlights important topics, ongoing disease outbreaks, and topics of interest to our clients. If you have any suggestions for improving our site, please email us by clicking on the TVMDL Support <mailto:support@tvmdl.tamu.edu> link at the bottom of the page.
DIAGNOSTIC UPDATES/INTERESTING CASES
Canine Schistosomiasis (Dr. Jim Trybus)
An adult male, mixed breed dog was presented to the regular veterinarian due to continued tenesmus and hematochezia. Upon examination multiple, variably sized growths were observed and palpated along the rectal mucosa. One of the larger lesions was biopsied and submitted to TVMDL for histological evaluation.
Histopathological examination of the rectal growth revealed expansion and effacement of the submucosa by granulomatous inflammation centered on schistosome ova with hemorrhage. The ova were round to ovoid and 75 to 100 microns in diameter with a folded to collapsed hyalinized wall typically surrounding a developing miracidium. The inflammatory response consisted of coalescing granulomas composed of epitheloid macrophages and multinucleated giant cells centered the parasitic ova admixed with moderate to large numbers of lymphocytes, plasma cells, and neutrophils supported by mild fibrosis. Low numbers of ova and mild inflammation extends into the mucosal lamina propria.
The findings were consistent with rectal schistosomiasis. Heterobilharzia Americana is the causative agent of canine schistosomiasis and occurs in the southern United Stated. Although humans are not capable of being definitive hosts, the parasite can cause a self-limiting irritation of the skin called “Swimmers itch.” The organism uses snails of the family Lymnaeidae as an intermediate host and raccoons, bobcats, nutrias, rabbits and wild and domestic canids can act as definitive hosts. Deposition of eggs in feces from an infected animal into a fresh water source results in hatching of the schistosome eggs and release of the miracidia, which penetrate the snail host. Cercaria develop and are released from the snail host and infect unsuspecting vertebrate hosts by direct penetration of the integument. In the definitive hosts, the parasites migrate to the liver, mature, and move to the mesenteric vessels. Ova are subsequently released and either passed in the feces or trapped most commonly in the wall of the intestine, liver or pancreas with the subsequent development of an inflammatory response and vague clinical signs.
As the eggs do not readily float, routine fecal flotation results are typically negative. Direct fecal smears and fecal sedimentation exams are needed to diagnose active infections. Treatment with Praziquantel or Fenbendazole at the approved dosages is effective. Prevention of infection can be achieved by keeping dogs out of stagnant water (ponds, creeks, and canals), especially water sources where other dogs are known to defecate.