Pharmacokinetic study of slaframine in lactating goats and transfer into milk

Slaframine is an alkaloidal mycotoxin produced by the fungus Rhizoctonia leguminicola. This mycotoxin is responsible for Blackpatch disease on clover and other legumes and Slobber disease in livestock. Slaframine causes salivation, lacrimation, urination, and defecation in intoxicated animals;The goal of this research was to do a preliminary pharmacokinetic study on slaframine in lactating goats and determine if slaframine was transferred into milk. Slaframine was produced to dose five lactating Saanen goats at a level of 0.05 mg/kg. The slaframine was delivered as an IV bolus dose. Blood, milk, and saliva samples were collected at timed intervals;All samples were analyzed by a newly developed HPLC procedure for slaframine. This procedure used fluorescamine derivatized slaframine to enhance detection 10-fold over previous GC technology. The slaframine derivative was found to be stable for several weeks. The mean recoveries of slaframine from plasma, milk, and saliva were 95%, 91%, and 82%, respectively;The pharmacokinetic study indicated a two compartment model. The half-life for the elimination phase derived for the sample-mean of all five goats was 1.28 hours. The volume of distribution indicated that slaframine was highly protein-bound in goat blood. The mean clearance value of slaframine was 2.6 ml/kg/h, indicating a rapid elimination of slaframine from the body;Due to the unpredictably long half-life of slaframine in the milk, sampling duration was insufficient in all but one goat to study the pharmacokinetics of slaframine in milk. This data would best describe the pharmacokinetic behavior as a two- or three- compartment model. As a two-compartment model, the elimination phase of slaframine in milk was 23 hours. To describe the data as a three-compartment model, (with or without a deep compartment) lower levels of slaframine would need to be detected in plasma. Higher levels of slaframine were seen in milk than in plasma, which correlates well with the pH partition theory. A milk/plasma ratio of 20:1 was obtained using experimental pH values;As a result of slaframine transfer into milk, a potential hazard exists for nursing goats and consumers of goat milk and its by-products. Further studies are necessary for making risk assessments for young animals with the occurrence of slaframine in milk

Improved Tissue-Based Analytical Test Methods for Orellanine, a Biomarker of Cortinarius Mushroom Intoxication.

Orellanine (OR) toxin is produced by mushrooms of the genus Cortinarius which grow in North America and in Europe. OR poisoning is characterized by severe oliguric acute renal failure, with a mortality rate of 10%-30%. Diagnosis of OR poisoning currently hinges on a history of ingestion of Cortinarius mushrooms and histopathology of renal biopsies. A key step in the diagnostic approach is analysis of tissues for OR. Currently, tissue-based analytical methods for OR are nonspecific and lack sensitivity. The objectives of this study were: (1) to develop definitive HPLC and LC-MS/MS tissue-based analytical methods for OR; and (2) to investigate toxicological effects of OR in mice. The HPLC limit of quantitation was 10 µg/g. For fortification levels of 15 µg/g to 50 µg/g OR in kidney, the relative standard deviation was between 1.3% and 9.8%, and accuracy was within 1.5% to 7.1%. A matrix-matched calibration curve was reproduced in this range with a correlation coefficient (r) of 0.97-0.99. The limit of detection was 20 ng/g for LC-MS/MS. In OR-injected mice, kidney OR concentrations were 97 ± 51 µg/g on Day 0 and 17 ± 1 µg/g on termination Day 3. Splenic and liver injuries were novel findings in this mouse model. The new tissue-based analytical tests will improve diagnosis of OR poisoning, while the mouse model has yielded new data advancing knowledge on OR-induced pathology. The new tissue-based analytical tests will improve diagnosis of OR poisoning, while the mouse model has yielded new data advancing knowledge on OR-induced pathology

Midazolam Efficacy Against Acute Hydrogen Sulfide-Induced Mortality and Neurotoxicity.

Hydrogen sulfide (H2S) is a colorless, highly neurotoxic gas. It is not only an occupational and environmental hazard but also of concern to the Department of Homeland Security for potential nefarious use. Acute high-dose H2S exposure causes death, while survivors may develop neurological sequelae. Currently, there is no suitable antidote for treatment of acute H2S-induced neurotoxicity. Midazolam (MDZ), an anti-convulsant drug recommended for treatment of nerve agent intoxications, could also be of value in treating acute H2S intoxication. In this study, we tested the hypothesis that MDZ is effective in preventing/treating acute H2S-induced neurotoxicity. This proof-of-concept study had two objectives: to determine whether MDZ prevents/reduces H2S-induced mortality and to test whether MDZ prevents H2S-induced neurological sequelae. MDZ (4 mg/kg) was administered IM in mice, 5 min pre-exposure to a high concentration of H2S at 1000 ppm or 12 min post-exposure to 1000 ppm H2S followed by 30 min of continuous exposure. A separate experiment tested whether MDZ pre-treatment prevented neurological sequelae. Endpoints monitored included assessment of clinical signs, mortality, behavioral changes, and brain histopathological changes. MDZ significantly reduced H2S-induced lethality, seizures, knockdown, and behavioral deficits (p < 0.01). MDZ also significantly prevented H2S-induced neurological sequelae, including weight loss, behavior deficits, neuroinflammation, and histopathologic lesions (p < 0.01). Overall, our findings show that MDZ is a promising drug for reducing H2S-induced acute mortality, neurotoxicity, and neurological sequelae

Plasma concentrations of sodium salicylate in nursery pigs treated orally

Objectives: To determine stability of acetylsalicylic acid (ASA) and sodium salicylate (SS) stock solutions, and to determine plasma concentrations of SS in swine after administration in drinking water. Materials and methods: Stock solutions of liquid ASA and SS products were placed in a nursery environment for 24 hours (Trial One). Salicylate concentrations were measured at 0, 8, 16, and 24 hours using high pressure liquid chromatography (HPLC). In Trial Two, SS was metered into the drinking water of four groups of pigs in a commercial nursery, at stock solution concentrations of 2268 mg per L (T1), 4913 mg per L (T2), 9827 mg per L (T3), and 19,654 mg per L (T4). Controls received nonmedicated water. Plasma salicylate concentrations in 10 pigs per group were measured at 0, 24, 60, and 72 hours. Results: Salicylate concentration ranges of stock solutions in Trial One were 4.04 to 4.61 g per L (ASA) and 8.19 to 9.34 g per L (SS). In Trial Two, mean plasma salicylate concentration ranges for treated groups over the 72-hour study were 0.17 to 0.41 mg per L (T1), 0.03 to 1.28 mg per L (T2), 0.44 to 1.41 mg per L (T3), and 0.62 to 7.22 mg per L (T4). Mean concentrations increased at 24 hours post study initiation, then decreased for all treated groups at 60 hours. Implications: Solubilities of ASA and SS products differ. Sodium salicylate administered via a water-medication system reaches measurable plasma concentrations in nursery pigs. Consistency of dosing may be variable

Evaluation and Observations of Total Sulfur Intake with Corn Co-Product Diets for Feedlot Cattle

Four complete feedlot rations between 41 & 48 Mcal/cwt Net Energy Gain (NEg) containing corn coproducts were analyzed to determine total percent sulfur on a dry matter basis (DMB). Ration sulfur level averaged 0.37% and ranged from 0.28-0.50%. Water sulfur content averaged 134 ppm and ranged from 98-205 ppm. The College of Veterinary Medicine spreadsheet to determine total sulfur intake calculated that the 650 pound steer consuming 20 pounds of a 44 Mcal/cwt NEg ration with 0.37% sulfur and water with 134 ppm sulfur was consuming 0.46% total sulfur intake. Twenty percent of the total sulfur comes from the water. Nine complete feedlot rations containing corn co-products were analyzed between 50 & 58 Mcal/cwt NEg to determine total percent sulfur on a DMB. Ration sulfur averaged 0.33% and ranged from 0.21-0.46%. Water sulfur content averaged 32 ppm and ranged from 5-83 ppm. The College of Veterinary Medicine spreadsheet to determine total sulfur intake calculated that the 800 pound steer consuming 24 pounds of a 55 Mcal/cwt NEg ration with 0.33% sulfur and 32 ppm sulfur water was consuming 0.35% total sulfur intake

Lick Tanks to Deliver Condensed Corn Distillers Solubles to Summer Grazing Beef Cows

This project was a preliminary investigation of the use of lick tanks to deliver condensed corn distillers soluble (CCDS) to summer grazing beef cows. During the first four paddock rotations, there was an increase in the amount of pasture dry matter consumed. As hot, dry weather persisted, forage quality and hence, pasture dry matter intake declined. This was accompanied by increased dry matter consumption of CCDS. Dry matter consumption of CCDS ranged from 2.66 pounds (14.8 pounds as-fed at the beginning of the project) to 8.11 pounds (30 pounds as-fed near the end of the project). Dietary intake of sulfur ranged from .43 to .62% of total diet dry matter. However, cattle health appeared to be unaffected by CCDS intake. Mold analyses for the CCDS are incomplete. Yeasts were consistently isolated from the assayed samples, but very few colonies of filamentous fungi (molds) were recovered. In fact, in most samples mold colonies were not detected. Mycotoxins were non-detectable for all mycotoxins analyzed, except fumonisins, which were present at low levels in all CCDS samples and likely came from the original grain. This data suggests that, if carefully managed, lick tanks may be used to deliver CCDS to summer grazing cows. However, the cows in this project had access to ample quantities of pasture and corn silage. A shortage of additional feedstuffs could alter the conclusions of this project

The occurrence and concentration of mycotoxins in U.S. distillers dried grains with solubles

To provide a scientific sound assessment of the prevalence and levels of mycotoxins in U.S. distillers' dried grains with solubles (DDGS), we measured mainly aflatoxins, deoxynivalenol, fumonisins, T-2 toxin, and zearalenone in 235 DDGS samples collected from 20 ethanol plants in the midwestern United States and 23 export shipping containers from 2006 to 2008 using stateof-the-art analytical methodologies. The results suggested that (1) none of the samples contained aflatoxins or deoxynivalenol levels higher than the U.S. Food and Drug Administration (FDA) guidelines for use in animal feed; (2) no more than 10% of the samples contained fumonisin levels higher than the recommendation for feeding equids and rabbits, and the rest of the samples contained fumonisins lower than FDA guidelines for use in animal feed; (3) none of the samples contained T-2 toxins higher than the detection limit, and no FDA guidance levels are available for T-2 toxins; (4) most samples contained zearalenone levels lower than the detection limit, and no FDA guidance levels are available for zearalenone; and (5) the containers used for export shipping of DDGS did not seem to contribute to mycotoxin production. This study was based on representative DDGS samples from the U.S. ethanol industry, and the data were collected using reference methods. This study provided a comprehensive and scientifically sound assessment of the occurrence and levels of mycotoxins in DDGS from the U.S. ethanol industry

Maternal alcohol ingestion reduces SP-A expression by pre-term fetal lung epithelia

In addition to neurodevelopmental effects, alcohol consumption at high levels during pregnancy is associated with immunomodulation and premature birth. Premature birth, in turn, is associated with increased susceptibility to various infectious agents such as Respiratory Syncytial Virus (RSV). The initial line of pulmonary innate defense includes the mucociliary apparatus, which expels microorganisms trapped within the airway secretions. Surfactant proteins A and D (SP-A and SP-D, respectively) are additional components of pulmonary innate immunity and have an important role in pulmonary defense against inhaled pathogens. The purpose of this study was to determine if chronic alcohol consumption during the third trimester of pregnancy alters the function of the mucociliary apparatus and expression of SP-A and SP-D of fetal lung epithelia. Sixteen, date-mated ewes were assigned to two different groups; an ethanol exposed group in which ewes received ethanol through surgically implanted intra-abomasal cannula during the third trimester of pregnancy, and a control group in which ewes received the equivalent amount of water instead of ethanol. Within these two groups, ewes were further randomly assigned to a full-term group in which the lambs were naturally delivered, and a pre-term group in which the lambs were delivered prematurely via an abdominal incision and uterotomy. Ethanol was administered 5 times a week as a 40% solution at 1gr/kg of body weight. The mean maternal serum alcohol concentration (SAC) measured 6 hr post administration was 16.3 +/− 4.36 mg/dL. Tracheas from 6 full-term lambs were collected to assess ciliary beat frequency (CBF). The lung tissue from all (24) lambs was collected for immunohistochemistry (IHC) analysis of SP-A and SP-D protein production and fluorogenic real-time quantitative polymerase chain reaction analysis (qPCR) of SP-A and SP-D mRNA levels. Exposure to ethanol during pregnancy significantly blocked stimulated increase in CBF though ethanol-mediated desensitization of cAMP-dependant protein kinase (PKA). In addition, pre-term born/ethanol-exposed lambs showed significantly decreased SP-A m-RNA expression when compared to the pre-term born/control group (p=0.004); no significant changes were seen with SP-D. The full-term/ethanol exposed lambs had no significant alterations in mRNA levels, but had significantly less detectable SP-A protein when compared to the full-term/control lambs (p=0.02). These findings suggest that chronic maternal ethanol consumption during the third trimester of pregnancy alters innate immune gene expression in fetal lung. These alterations may underlie increased susceptibility of pre-term infants, exposed to ethanol in utero, to RSV and other microbial agents

Pharmacokinetic study of slaframine in lactating goats and transfer into milk

Slaframine is an alkaloidal mycotoxin produced by the fungus Rhizoctonia leguminicola. This mycotoxin is responsible for "Blackpatch" disease on clover and other legumes and "Slobber" disease in livestock. Slaframine causes salivation, lacrimation, urination, and defecation in intoxicated animals;The goal of this research was to do a preliminary pharmacokinetic study on slaframine in lactating goats and determine if slaframine was transferred into milk. Slaframine was produced to dose five lactating Saanen goats at a level of 0.05 mg/kg. The slaframine was delivered as an IV bolus dose. Blood, milk, and saliva samples were collected at timed intervals;All samples were analyzed by a newly developed HPLC procedure for slaframine. This procedure used fluorescamine derivatized slaframine to enhance detection 10-fold over previous GC technology. The slaframine derivative was found to be stable for several weeks. The mean recoveries of slaframine from plasma, milk, and saliva were 95%, 91%, and 82%, respectively;The pharmacokinetic study indicated a two compartment model. The half-life for the elimination phase derived for the sample-mean of all five goats was 1.28 hours. The volume of distribution indicated that slaframine was highly protein-bound in goat blood. The mean clearance value of slaframine was 2.6 ml/kg/h, indicating a rapid elimination of slaframine from the body;Due to the unpredictably long half-life of slaframine in the milk, sampling duration was insufficient in all but one goat to study the pharmacokinetics of slaframine in milk. This data would best describe the pharmacokinetic behavior as a two- or three- compartment model. As a two-compartment model, the elimination phase of slaframine in milk was 23 hours. To describe the data as a three-compartment model, (with or without a deep compartment) lower levels of slaframine would need to be detected in plasma. Higher levels of slaframine were seen in milk than in plasma, which correlates well with the pH partition theory. A milk/plasma ratio of 20:1 was obtained using experimental pH values;As a result of slaframine transfer into milk, a potential hazard exists for nursing goats and consumers of goat milk and its by-products. Further studies are necessary for making risk assessments for young animals with the occurrence of slaframine in milk.</p

Determination of Serum Sodium Salicylate Concentrations in Swine Resulting from Administration through Water Medication Systems

Aspirin is widely used in food animal production for pain relief and fever reduction due to the current lack of antiviral drugs, the inexpensive cost, and the over-thecounter availability. However, there is no reported information on dosage or achievable plasma or serum concentrations when acetylsalicylic acid or sodium salicylate products are administered via water medicator dosing systems typically used in swine production facilities. Significant differences are reported in the solubility of aspirin and sodium salicylate in water. These differences potentially impact the amount of each product that can be provided to pigs via water medication systems. Additionally, dose data for the oral route of administration is based on the provision of a daily dose in a single oral gavage. This differs from the typical application in swine where a daily dose is consumed over a 24 hour period via the drinking water. Reported differences in solubility were confirmed in the first phase of this trial. The second phase selected the most soluble product (sodium salicylate) and administered four concentrations to commercial swine for 72 hours. Serum plasma levels were analyzed by HPLC from 10 randomly selected pigs in each group including controls at 0, 24, 60, and 72 hours post administration. Sodium salicylate reached peak serum levels 24 hours post administration and exhibited a dose dependent trend. This study provided information necessary to perform future challenge trials for dose determination.</p