TVMDL maintains two laboratories dedicated to poultry diagnostics, one in Center, Texas and the other in Gonzales, Texas. Veterinarians, with assistance from TVMDL, service the Texas animal health industry by certifying poultry are healthy. With the help of TVMDL, veterinarians can ensure the best and safest sample collection technique when collecting samples from a live-bird. […]

TVMDL maintains two laboratories dedicated to poultry diagnostics, located in Center, Texas and Gonzales, Texas. With the help of TVMDL, veterinarians can learn the best method to safely take a blood sample from poultry; the sample TVMDL uses to test for diseases like Avian Influenza, Salmonella or Mycoplasma. Veterinarians service the Texas animal health industry […]

The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) Analytical Chemistry Section has the ability to offer toxicology and drug testing services to livestock producers and practitioners. The lab offers a variety of tests to aid in diagnosing many conditions of both toxic and nutritional origin. Our highly trained and qualified personnel use state-of-the-art analytical techniques […]

Fumonisin B1 is the most prevalent of several fumonisin mycotoxins (B1, B2, B3) produced by Fusarium molds in corn. Corn contamination can occur at very high levels when permissive environmental conditions coincide with vulnerable points in corn kernel production. Equine Leukoencephalomalacia (ELEM) Horses and other equids, as well as rabbits, are the most fumonisin-sensitive species. […]

Prior to diagnostic testing, it’s important to determine what factors would lead to the most comprehensive assessment of an animal’s condition. Each case must be evaluated individually in order to establish the most practical diagnostic testing route.  Collection Guidelines What is an ideal serum sample? Since most serologic testing utilizes serum, blood should be collected […]

The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) performs numerous tests using serum. Proper collection, preparation, and packaging for transportation is imperative to obtaining a quality serum sample. Serum samples that arrive at TVMDL which are hemolyzed and/or lipemic may not be acceptable for testing. Accurate results start with an ideal sample. Ideal Sample Clear […]

Hundreds of samples arrive daily at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for testing. Testing accuracy often depends on submission of the proper specimen for the assay, particularly for molecular diagnostics.  To ensure the appropriate sample is submitted for molecular diagnostics at TVMDL, please consult the website for specific details associated with the […]

Hundreds of samples arrive daily at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for testing. Testing accuracy often depends on the submission of the proper specimen for the assay, particularly for molecular diagnostics. With the proper sample, we can perform the assay and provide the most timely and accurate results without delay.  While results […]

Click to Skip: Autolysis | Cautery Artifact | Freezing Artifact | Crush Artifact | Sponge Artifact Pathologic artifacts are any structures or features that are not normally present in the living animal. Some are minor, easy to distinguish from normal or diseased tissue, and/or do not interfere with the pathologists’ ability to provide an accurate […]

Seven dead, 16-week-old bobwhite quail were presented to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Gonzales for necropsy. The history provided noted increased mortality of about 15 birds per day, with no clinical symptoms.  The birds were in flight pens with no vegetation.  Additionally, all birds had varying degrees of feather loss around […]

The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Gonzales received a phone call concerning a decrease in production and poor performance of a backyard flock of chickens used as an egg source for the family. Further discussions with the caller revealed the chickens had access to an old building with peeling paint that the chickens […]

Dermatology cases are one of the most common types of cases seen by general practitioners. A crucial diagnostic tool in these cases is the skin biopsy. They are indicated in cases that do not respond to normal therapy, pustular, or ulcerative disease, and suspected neoplasia.  Before Taking a Skin Biopsy Prior treatment should also be […]

Click to Skip: Bone Marrow Aspirate Procedure | Bone Marrow Core Biopsy Procedure Bone marrow testing is used to diagnose and monitor bone marrow diseases and CBC abnormalities. Full evaluation of bone marrow requires a CBC the day of the bone marrow collection, bone marrow aspiration, and a bone marrow core biopsy.  Indications for bone […]

The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) offers digital cytology to account-holding clients. Digital cytology provides rapid evaluation of photos taken with microscope cameras or smart phones. This service provides an official report and cytologic interpretation, typically within one hour of submission (during business hours). To enhance this service, submission of glass slides for […]

The collection of feather samples should be undertaken by a competent individual within a secure, contamination-free facility. Ideally, the collector should wear gloves when handling feathers. Collection Supplies Collecting the Sample Before collection, make sure all scissors intended for collection are clean. It is recommended the collector use an alcohol wipe to clean scissors before […]

The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) has been providing drug testing services for livestock shows across the country for more than 30 years. The agency tests in excess of 3,500 samples for more than 90 shows across the United States annually. TVMDL’s drug testing laboratory is an ISO 17025 accredited lab with state-of-the-art […]

 In addition to managing two of the state’s poultry health programs, TVMDL helps keep Texas’ birds healthy through dedicated high-volume testing at the Center and Gonzales locations. In the five-year period between March 2019 and February 2024, TVMDL’s poultry laboratories performed over 1 million serologic tests for avian influenza, Mycoplasma, and Salmonella. While most of those tests […]

Nematodes of the genus Baylisascaris are recognized as causes of avian cerebral nematodiasis. Baylisascaris columnaris, the ascarid of skunks and Baylisascaris procyonis, the ascarid of raccoons, have been documented as the species responsible for this disease. The disease occurs after consumption of the ascarid eggs in contaminated feed or picked up from the ground of contaminated premises. The bird […]

A flock of approximately 10,000 Coturnix quail, aged 5.5 months, were experiencing mild diarrhea and various vague neurological symptoms resulting in a spike in mortality over the previous few days. Four dead 5.5-month-old Coturnix quail were presented for necropsy at TVMDL’s Gonzales laboratory. The quail were euthanized on the farm prior to submission. Birds weighed […]

 A female Gray Barred chicken was presented to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Gonzales. The chicken was approximately 2 years old and weighed 1.41 kilograms.  Following necropsy evaluation, it was noted that within the coelomic cavity there were numerous 1-4 mm in diameter white nodules on the serosal surface of the […]

The non-stick coating polytetrafluoroethylene (TeflonTM) on cookware, light bulbs, and ovens releases fluorinated gases upon overheating. This is particularly important with pet birds, but can be observed in poultry with polytetrafluoroethylene-coated heat lamp bulbs. These gases are highly toxic to the epithelium of the deep airways and endothelium of the blood capillaries.   Birds exposed to […]

Twelve 11 and 12-week-old broiler breeder pullets from two farms were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Center, Texas for a diagnostic evaluation. The birds were submitted with a clinical history of having bumps on the face. Upon clinical examination, the birds exhibited nodular protuberances, approximately 1 cm in length, […]

Bordetellosis is a highly contagious upper respiratory tract disease of poultry caused by Bordetella avium, a gram-negative motile aerobic rod-shaped bacterium. B. avium is primarily a disease of turkeys, although the organism has been shown to infect chickens and other avian species. Initially, it causes a clear nasal exudate and foamy exudate in the medial canthus of the […]

A four-year-old Pacific eider (sea duck) was reported to have a history of open-mouth breathing. It had been treated for suspected aspergillosis prior to death and was submitted to Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for necropsy. At necropsy, the clinical suspicion of aspergillosis was confirmed. All air sacs were coated by green, velvety, […]

Depluming mites (Knemidocoptes gallinae, Neocnemidocoptes gallinae) are found worldwide and are related to the scaly leg mite (Knemidocoptes mutans). Depluming mites prefer feathered portions of the body while scaly-leg mites infest the non-feathered regions. Both mites spend their entire lives on the bird and do not survive long in the environment. The depluming mite burrows into […]

An unidentified microfilaria was found on a blood smear obtained from a 16-year old, female, captive penguin who was being treated for respiratory aspergillosis. The attending veterinarian submitted whole blood and a fresh blood smear to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for parasite identification.  Multiple microfilariae were seen on the submitted blood […]

Fowl Pox was diagnosed in three Houdan chickens submitted for diagnostic workup to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Center, Texas. Upon examination, the birds had either one or both eyes severely swollen, due to a large accumulation of caseous exudate, and moderate numbers of dark brown, 3 mm diameter, raised nodules […]

Ochroconosis is a sporadic fungal encephalitis that has been reported in young chickens, turkey poults, quail chicks, and wild birds. It is caused by a dematiaceous, thermophilic fungus, Ochroconis gallopava (Dactylaris gallopava). O. gallopava is a ubiquitous fungus found in hot spring environments, soil, wood, and decaying vegetation. In birds, ochroconosis has been associated with contaminated litter and egg […]

Twenty turkey vultures were found dead near the vicinity of a horse that was euthanized. One of the turkey vultures was submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for necropsy. Postmortem decomposition hindered a thorough diagnostic necropsy. Portions of all major organs were collected, and liver was submitted to TVMDL’s drug testing […]

Ten live 20-day-old, meat type chickens were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory’s (TVMDL) Center laboratory with a clinical history of leg problems and swollen tendons. At necropsy examination the birds exhibited outwardly deviated legs, moderately swollen hocks with an accumulation of a tannish, turbid exudate, and swollen gastrocnemius tendons. Serology for […]

Mycoplasma synoviae (MS) infection was diagnosed in a flock of 113-day-old, brown feathered, meat type, chickens. Ten live birds were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Center, TX with a clinical history of respiratory problems and increased mortality. At the necropsy examination, the birds had tracheas with reddened mucosa and excess […]

A dead one-year-old female Red Sex-Link chicken was presented to the Texas A&M Veterinary Medical Diagnostic Laboratory in Gonzales, Texas for necropsy examination. Clinical history noted that it was found dead with no previous clinical illness noticed. The bird was fed an organic layer feed, vegetables, and fruit. History also noted the bird had no […]

Rickets was diagnosed in a live, 3-month-old, backyard type, female chicken. The bird was submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Center, Texas, for testing. The bird was depressed and showing respiratory distress. The findings at the necropsy examination included moderate emaciation, fragile bones with increased width of the bone growing […]

The causative agent of histomoniasis is a protozoan parasite Histomonas meleagridis. Numerous gallinaceous birds are affected by this parasite including turkeys, chickens, chukar partridges, peafowl, pheasants, and ruffed grouse.  H. meleagridis is commonly transmitted in embryonated eggs of the common cecal worm, Heterakis gallinarum. Chickens and other gallinaceous birds harbor this worm, which acts as a reservoir. In turn, […]

Six 16-week-old male chickens from a flock of 500 birds were presented for necropsy at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Gonzales. History noted one-week of swollen sinuses with minimal abnormal respiratory sounds and negligible mortality.  The incidence was relatively low. Upon necropsy examination, each of the six birds had one of […]

“Hardware disease” in backyard chickens and other birds is caused by the ingestion of metal objects present in their environment. These objects range from sharp objects that ultimately penetrate the gizzard to objects that may contain zinc or lead leading to zinc or lead toxicosis or some other heavy metal toxicosis. Two case histories are […]

Severe coccidiosis was diagnosed in a 22-week-old, broiler breeder flock. Three dead birds were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Center for examination. The birds were submitted with a clinical history of sudden increase in mortality. At necropsy, the birds had moderately dilated and flaccid jejunum and ileum, with their […]

 Fowl pox is caused by a DNA virus (fowl pox virus).  Many species of birds have their own specific pox virus. Infection can occur in two different forms: dry and wet. Dry pox occurs through mechanical transmission of the virus to injured or lacerated skin and can occur at any age. Biting insects, such as […]

Recently, the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Center diagnosed gangrenous dermatitis (GD) in three flocks of broilers 44 to 50 days of age. All the submissions had a common clinical history of sudden increased mortality, prostration, and change in color of the skin. At necropsy examination, the birds had purple discoloration of […]

Twelve dead adult Chukar partridges were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Gonzales for necropsy. History noted an increase in spontaneous deaths over a few days’ period with minimal or no clinical signs observed. Upon necropsy examination, the birds had enlarged, pale, orange-colored livers and enlarged, dark spleens. The lungs […]

Mycoplasmosis, caused by Mycoplasma gallisepticum and/or M. synoviae, is a group of bacterial diseases that are common maladies of backyard chicken flocks. Mycoplasma gallisepticum (MG) is the most common upper respiratory infection of backyard chicken flocks. The characteristic signs of naturally occurring infections are watery eyes, tracheal rales, nasal discharge, and coughing (Figure 1). Feed consumption is reduced, […]

Salt toxicity was diagnosed in a 17-day-old, meat type chicken flock. Twelve birds were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Center. Clinical history noted increased mortality starting at 2-weeks-old. At necropsy examination, all the birds had an edematous brain with poorly defined cerebellar folia and cerebrum lobes, thin blood, and […]

A 6-month-old Harris’s hawk was necropsied at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in College Station and was diagnosed with herpesvirus infection as the cause of death. This hawk was used as an abatement bird and had been previously diagnosed with and treated for oral trichomoniasis. The patient passed away and was submitted […]

Three dead and eight live 17-week-old bobwhite quail were presented to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Gonzales for necropsy with a history of ongoing weight loss and an increase in mortality.  One live bird died prior to examination.  The remaining live birds were mildly depressed. Upon necropsy examination, birds ranged in […]

A 5-month-old female chicken with a history of dyspnea was presented to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Gonzales for necropsy. Duration of illness was approximately one week. This bird was the only one that had died out of a flock of four. Upon examination, the bird weighed 692 grams and had […]

The Texas A&M Veterinary Medical Diagnostic Laboratory’s (TVMDL) Center laboratory discovered salmonellosis in a flock of 75 racing pigeons. At the time of specimen submission, 25 birds had already died. Sick birds were showing regurgitation, greenish feces, and sudden death following onset of clinical signs. At necropsy examination, two birds had enlarged and mottled livers […]

Five live 30-week-old laying chickens were presented to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Gonzales for necropsy. Birds were weak, lethargic, and depressed. The flock had a history of severe production drop starting approximately four weeks following housing in the laying facility at 22 weeks of age. Clinical signs included coughing, droopiness, […]

Recently, one dead, female, Cream Legbar chicken was presented to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Gonzales for necropsy. The bird had excellent feathering, was in good post-mortem condition, and weighed 1.06 kilograms. Upon gross examination, mild breast muscle atrophy was present.The liver was enlarged approximately five times normal size and contained […]

Staphylococcosis and fowl pox were diagnosed at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) poultry lab in Center, TX, in a flock of 17-week-old, meat type, breeder, chickens. Three dead birds were submitted for laboratory examination. Grossly, all the birds had moderately swollen gastrocnemius tendons and hocks, as well as moderate to large numbers […]

One live male guinea fowl was presented to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for necropsy. History noted the bird was bright and alert, but moved very little, appeared cold and very thin – only weighing 514 grams. Upon evaluation, marked breast muscle atrophy was present.  The bird appeared pale and the blood […]

Histomoniasis, a protozoal disease of birds also known as “Blackhead”, was diagnosed in a flock of Bobwhite quail. Three dead females and one dead male, 8-month-old, Bobwhite quail were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) with a clinical history of increased mortality. History indicated the flock exhibited enteritis and had been […]

A flock of approximately 3000 Chukar partridges, aged five months and older, were experiencing a decrease in performance and a slight increase in mortality.  The birds continued to eat but many lost weight and eventually died.  No overt respiratory or digestive clinical signs were observed. Six live, 5-month-old Chukar partridges were presented to the Texas […]

Chlamydophilia psittaci is a bacterium that can be transmitted from pet birds to humans. In humans, the resulting infection is referred to as psittacosis and is also known as parrot disease, parrot fever, avian chlamydiosis, and ornithosis in avian species. This zoonotic disease can affect people after exposure to aerosolized organisms shed from the digestive or […]

Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) received several bobwhite quail (Colinus virginianus) for necropsy. The majority of submitted quail have come from various hunting preserves all across Texas. These facilities are reporting high mortalities, with some finding 200-400 birds dead each day. At necropsy, these quail have all been diagnosed with ulcerative enteritis. Ulcerative […]

Inclusion body hepatitis (IBH) was diagnosed in a flock of 12-day- old, meat type chickens. Six live and 4 dead birds were submitted to the TVMDL-Center Lab with a history of increased mortality, swollen kidneys, and whitish spots livers. At the necropsy examination livers were pale, mottled with a reticular pattern and with subcapsular hemorrhages; […]

A wildlife rehabilitation center submitted a biopsy from a hawk. The veterinarian examining the hawk noted a proliferative lesion on the non-feathered skin of the left talon. There are several infectious disease differentials for lesions on the talons of birds ranging from pododermatitis (bumblefoot), often caused by an underlying bacterial infection to various viral, fungal, […]

Necrotic enteritis associated with coccidiosis was diagnosed in 25-day-old broilers. Six live broilers with a history of increased mortality with birds dying with their legs straight out were submitted for laboratory examination. At necropsy, the mucosa of the jejunum and ileum had a “cloth towel” appearance with loose, small mucosal flakes. Moderate numbers of coccidia […]

A 12-month-old black and white female laying chicken from a small backyard flock was received for necropsy.  The owner had elected euthanasia of this bird following a clinical exam revealing acute abnormal respiration including open mouth breathing.  Another bird in the flock had similar clinical symptoms and had died.  Following euthanasia and refrigeration, the bird […]