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Simple Summary: In Texas beef markets, the expansion of ethanol production has increased the demand for and utilization of biofuel co-products, like dried distiller grains with solubles, introducing highly variable concentrations of nutrients, such as sulfur, known to impact cattle health. The risk of sulfur toxicity for Texas cattle was estimated using two mathematical nutrition models at two production stages across twelve geographic districts. The assessment identified cattle raised in the South Plains region of northwest Texas as the most susceptible to sulfur toxicity, with those in the finishing production stage being more sensitive. Results also highlighted feed ingredients and water wells by district that significantly contributed to the risk of sulfur toxicity. This research further helps better manage the risk of sulfur toxicity by providing tools translatable nationwide that properly balance beef diets and calculate anticipated sulfur exposure. The purpose of this probabilistic assessment was to estimate the risk of sulfur-induced polioencephalomalacia (S-PEM) for beef raised across Texas, from a dietary perspective. Ruminant nutritionists in Amarillo, TX, formulated two typical nutritional regimens based on cattle production stages, each containing six feed ingredients and well water. The Office of the Texas State Chemist (OTSC), National Research Council (NRC), and the published literature provided S data for feed ingredients. The Texas Water Development Board provided data for S content in Texas well water, categorized into twelve districts established by the Texas A&M AgriLife Research Extension Service. The S-PEM risk was estimated at five different eNDF levels ranging from 0% to 8% in 2% increments, using rumen degradable S (RDS) as an input value. Findings identified cattle raised in the South Plains district as the most susceptible population to S toxicity, with beef in the finishing production stage experiencing increased sensitivity. The most potential (MP) risk scenario suggested that the S-PEM risk could reach 28.5% for growers and 100% for finishers. Results further revealed that when S concentrations in well water exceeded 14.5 mg/L, water became the greatest contributor to RDS content for Texas beef, suggesting that high S content in well water is the most prominent concern for Texas beef. [ABSTRACT FROM AUTHOR]

The purpose of this probabilistic assessment was to estimate the risk of sulfur-induced polioencephalomalacia (S-PEM) for beef raised across Texas, from a dietary perspective. Ruminant nutritionists in Amarillo, TX, formulated two typical nutritional regimens based on cattle production stages, each containing six feed ingredients and well water. The Office of the Texas State Chemist (OTSC), National Research Council (NRC), and the published literature provided S data for feed ingredients. The Texas Water Development Board provided data for S content in Texas well water, categorized into twelve districts established by the Texas A&M AgriLife Research Extension Service. The S-PEM risk was estimated at five different eNDF levels ranging from 0% to 8% in 2% increments, using rumen degradable S (RDS) as an input value. Findings identified cattle raised in the South Plains district as the most susceptible population to S toxicity, with beef in the finishing production stage experiencing increased sensitivity. The most potential (MP) risk scenario suggested that the S-PEM risk could reach 28.5% for growers and 100% for finishers. Results further revealed that when S concentrations in well water exceeded 14.5 mg/L, water became the greatest contributor to RDS content for Texas beef, suggesting that high S content in well water is the most prominent concern for Texas beef.

The signature pathological feature of the pseudolaminar cerebrocortical necrosis found in polioencephalomalacia (PEM) of ruminants is the development of red (eosinophilic) neurons. These neurons are generally considered to be irredeemably injured but we have shown, for the first time, in ovine PEM cases, that most strongly express amyloid precursor protein (APP), which has a neuroprotective role in the brain. By contrast, neurons in unaffected cerebral cortices from control sheep were APP immunonegative. This finding suggests that, rather than being inevitably destined to die, some of these APP immunoreactive cortical neurons may survive and regain structural and functional integrity. [ABSTRACT FROM AUTHOR]

Objective: To assess the clinical efficacy and plasma concentrations of levetiracetam in a goat with seizures., Animal: A 5-month-old doeling., Clinical Presentation, Progression, and Procedures: The goat was referred because of progressive anorexia and lethargy over 3 days. Clinical signs consisted of weakness, obtundation, opisthotonos, anisocoria, and cortical blindness. Initial evaluation was most consistent with polioencephalomalacia., Treatment and Outcome: Neurologic improvement occurred within 4 hours of thiamine administration, with appetite returning over 12 hours. On day 3 of hospitalization, the goat suffered acute onset repetitive seizures that were incompletely responsive to standard interventions over 3 hours. Administration of IV levetiracetam (60 mg/kg) produced resolution of seizure activity within 20 minutes. Levetiracetam was continued twice daily IV, then PO after day 6. Plasma concentrations were above or within therapeutic ranges (5 to 45 μg/mL) as previously established for other species, following both IV and PO levetiracetam. Oral administration (60 mg/kg, PO, q 12 h) resulted in plasma levetiracetam concentrations of 48.1 μg/mL 2 hours after a dose and 23.4 μg/mL 2 hours prior to the next dose., Clinical Relevance: Levetiracetam is a newer anticonvulsant commonly used in humans and small animals due to its efficacy, cost, and wide safety margin. Its use has not previously been reported in domestic small ruminants. In this case, levetiracetam showed excellent clinical efficacy in the face of refractory seizures, with no apparent side effects. Plasma concentrations during oral administration were at the high end of the therapeutic range, indicating absorption in a nonmonogastric species. Further studies are warranted to determine optimal dosing in small ruminants.