Nitrate toxicity occurs when animals consume food or water that contains high levels of nitrates. In the rumen, nitrates are converted into a smaller compound called nitrites, which are then absorbed into the bloodstream. Ruminants are particularly susceptible because of their consistent grazing habits.  Alexis Thompson, DVM, Ph.D., DACVPM, is the resident director at the […]

Each test description in the online test catalog lists the proper sample submission, including collection container and shipping instructions. Follow the chart below and submit the sample in the correct tube.  Serum Plasma or Whole Blood Zinc Trace Material

When horses ingest the cantharidin toxin through hay or alfalfa contaminated with “blister” beetles, the outcome is often fatal. Toxicosis occurs rapidly; as little as four grams of dried beetles may contain fatal levels of cantharidin. Cantharidin is extremely toxic and fast-acting, quickly affecting a horse’s ability to function. All blister beetles carry cantharidin and […]

Photosensitization is a serious skin condition in horses and cattle caused by a hazardous combination of certain plants and ultraviolet (UV) light. Certain plants contain photodynamic agents, which then cause a reaction in the animal’s body that leads to ultra-sensitive skin. This condition is specific to lightly or non-pigmented animals or areas of an animal […]

The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) offers digital toxicology to account-holding clients. Digital toxicology provides evaluation of photos taken with smart phones, or other digital cameras, and an official report identifying items photographed (where possible) including an attachment with labeled photos for later reference – an advantage over shipping items to the laboratory […]

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. […]

Recently, seventeen cows died within twenty-four hours after consuming new hay. All of the cows died within 100 yards of the hay. A sample of the hay, along with tissue samples and ocular fluid from one of the cows were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for testing. Toxic levels of […]

The Texas A&M Veterinary Medical Diagnostic Laboratory’s (TVMDL) analytical chemistry section performed zinc testing on a small set of paired samples. Prior to testing, blood was collected from four clinically healthy animals and divided into two tubes with EDTA. One tube was a standard microtainer tube with a rubber o-ring buried in the groove of […]

Approximately 200 head of cattle were grazing on improved native Bermuda grass pastures in the Colorado River bottom. Vegetation also included a large number of oak trees, and a low number of nightshade, cocklebur, and coffee senna plants. Two 400 to 500 lb. calves were found down and unable to rise. Both calves died within […]

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 […]

Beetles found in a new batch of alfalfa hay were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for identification. TVMDL’s toxicology section can identify toxic and non-toxic beetles using microscopic examination. The beetles submitted were identified as Tiger beetles (Cicindelidae sp.) (Figure 1). Tiger beetles are characterized by having large, carnivorous mouth parts […]

The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) was contacted by a client who was concerned a group of horses had potentially consumed gopher bait containing an anticoagulant (diphacinone) as the toxic agent. Providing treatment for large animals with the antidote for anticoagulant intoxication can be challenging, therefore the suggestion was made to submit samples […]

In January, an animal owner in northwestern Washington State contacted the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) regarding possible blister beetles on their property. Specifically, the animal owner was interested in measuring the amount of cantharidin in a sampling of the beetles. Cantharidin is a very potent blistering agent, causing colic, heart arrhythmias and […]

A 7-year-old pastured mare suffered an acute onset of hemolytic anemia and hematuria. The blood drawn for analysis was hemolyzed and dark. The mare died about three hours after intravenous fluid therapy was begun. Whole blood, serum and a blood smear were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for evaluation. Clinical […]

A 3-year-old, male Quarter horse became ataxic and kept falling over, eventually being unable to rise. The horse ultimately had to be euthanized. The onset and severity of clinical signs occurred over a two-hour period. Serum was submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for an Equine Encephalitis Panel and corn and […]

Polioencephalomalacia “polio” is a syndrome of ruminant animals affecting the central nervous system. Seizures are the most notable sign, progressing quickly to the death of the affected animal without treatment. The underlying cause of the syndrome is a disturbance in thiamine (Vitamin B1) metabolism. Since ruminant animals can assemble B vitamins in their rumens, affected […]

In late March, the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) diagnosed senna toxicosis in two separate goat herds, from west and central Texas. In the first case, a 2-month-old goat kid was found suddenly dead along with one other goat kid. A third surviving kid was reported to be clinically ill. Histologically, the heart […]

TVMDL received a full set of fresh and fixed tissue samples and stomach content from a four-year-old Belgian Tervuren for testing. The dog appeared normal in the morning, running and playing in the yard. The owner found the dog deceased two hours later. It was noted that the dog liked to eat corn as it […]

The Texas A&M Veterinary Medical Diagnostic Laboratory received stomach content, fresh kidney, and serum from a two-month old mixed breed puppy for testing. The owner found the puppy deceased in the yard with foam coming from its mouth. Malicious poisoning was suspected as a neighbor previously threatened to poison the owner’s puppies. Given the uncertainty […]

Blue-green algae (cyanobacteria) barely take a break in warm winters. The most frequently observed blue-green algae that cause blooms in the greater Brazos Valley area are Microcystis sp., Oscillatoria sp., and Anabaena sp. These species all tend to produce microcystins, which are hepatotoxic to all species. In a recent case, clinical history noted a group of dogs playing in a pond thick with Microcystis colonies […]

Four dogs were brought to a veterinary clinic when one had been seizing for several hours and the other three had begun to tremble. All four dogs had reportedly been running loose in a rural area. Vomiting was induced in the worst of the tremblers, and all three of them responded to overnight pentobarbital/fluid therapy […]

Drought conditions can create two deadly dangers for a herd: water deprivation and water (salt) intoxication. Poor water quality will worsen these conditions. Water DeprivationHigh temperatures combined with a lack of fresh water or green forage can lead to dehydration and death. During a drought, a poorly managed herd may lack access to enough fresh […]

A male kitten was rescued by animal control and taken to a veterinary clinic for labored breathing, dehydration and severe jaundice. The kitten was euthanized and found to have petechial hemorrhaging and yellow fluid in the abdomen during the necropsy. Three days later, a tuna can with what appeared to be a suspect bright green […]

A nine month old, spayed female, domestic cat became neurologic and was unresponsive to supportive treatment. Upon death, the head and three sections of liver were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for histopathologic evaluation and toxicology testing. Following a negative rabies test, a portion of fixed brain was examined and […]

A two-month-old, 150-pound, Brahman-cross heifer calf was observed with neurologic signs following application of what was believed to be a permethrin-based insecticide. The calf died following symptomatic treatment. Fresh and fixed tissue samples were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for testing. A portion of fresh brain was extracted and analyzed […]

A cattle owner in eastern Texas noticed several of the 50 weaned calves in his coastal pasture had diarrhea and didn’t seem to want to eat. The pasture had been sprayed with monosodium methyl arsenate (MSMA) to kill weeds about 10 days prior and was fertilized at 300 lbs per acre three days before the […]

Approximately 40 head of Hereford cows were grazing on 12 sections of land with oil production activity present. In one particular section, four to five cows were found dead within 12-24 hours. Another cow was observed by the owner to be shaking and trembling, had fallen and gotten up, fell a second time and became […]

Since the onset of winter, the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) has seen quite a few cases of intoxication in cattle that have consumed the coffee senna (Senna occidentalis) plant. Most of the cases involved adult cattle that were found dead by the owners. The diagnosis was made by finding evidence of the plant in the […]

A herd of 14, six-month-old crossbred cattle was turned out into a new pasture. Within five days, five head died suddenly. An old barn with various abandoned and discarded metal and equipment was noted to be in the pasture. Chemical poisoning of an unknown origin was suspected. A 500-pound steer was submitted to the Texas […]

During the winter, the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) typically sees submissions in newborn calves described as “weak”, “dummy”, “maladjusted”, and “poor doer”. Most commonly, these animals are born alive but lack normal vigor and die within the first week of life. Postmortem exam and ancillary diagnostic testing has shown vitamin and trace […]

Fifteen crossbred calves were placed in a pasture with a burn-pile. The day after they were provided with Johnson grass hay, one calf was found dead. Two days later, three calves were walking abnormally and had diarrhea. Feces from those calves was submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for testing. Fecal […]

A herd of steers, weighing approximately 700 lbs. and roughly 8 months old, was moved onto a ryegrass/native pasture. After about a month, four steers were found dead while 17 steers exhibited peeling and crusting noses with thickening of ear and eye margins. The animals did not exhibit any clinical signs of illness and were […]