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Serum elimination profiles of methyllycaconitine and deltaline in cattle following oral administration of larkspur (Delphinium barbeyi)
2009
Green, Benedict T. | Welch, Kevin D. | Gardner, Dale R. | Stegelmeier, Bryan L. | Davis, T Zane | Cook, Daniel | Lee, Stephen T. | Pfister, James A. | Panter, Kip E.
Objective--To describe the simple elimination kinetics of methyllycaconitine (MLA) and deltaline and evaluate the heart rate response in cattle following oral administration of larkspur. Animals--5 healthy Angus steers that were habituated to metabolism crates. Procedures--Tall larkspur (Delphinium barbeyi) in the early flowering stage was collected, dried, and ground. Each steer received a single dose of larkspur that was equivalent to 10.4 mg of MLA/kg and 11.0 mg of deltaline/kg via oral administration. Steers were housed in metabolism crates during a 96-hour period following larkspur administration; heart rate was monitored continuously, and blood samples were collected periodically for analysis of serum MLA and deltaline concentrations as well as assessment of pharmacokinetic parameters. Results--No overt clinical signs of poisoning developed in any steer during the experiment. Mean ± SE heart rate reached a maximum of 79.0 ± 5.0 beats/min at 17 hours after larkspur administration. Serum MLA concentration was correlated directly with heart rate. Mean times to maximal serum concentration of MLA and deltaline were 8.8 ± 1.2 hours and 5.0 ± 0.6 hours, respectively. Mean elimination half-life values for MLA and deltaline were 20.5 ± 4.1 hours and 8.2 ± 0.6 hours, respectively. Conclusions and Clinical Relevance--Following larkspur administration in 5 healthy steers, maximum serum concentrations of MLA and deltaline were detected within 10 hours, and changes in serum MLA concentration and heart rate were correlated. Results indicated that cattle that have consumed larkspur will eliminate 99% of MLA and deltaline from serum within 144 hours.
Show more [+] Less [-]Effects of larkspur (Delphinium barbeyi) on heart rate and electrically evoked electromyographic response of the external anal sphincter in cattle
2009
Green, Benedict T. | Pfister, James A. | Cook, Daniel | Welch, Kevin D. | Stegelmeier, Bryan L. | Lee, Stephen T. | Gardner, Dale R. | Knoppel, Edward L. | Panter, Kip E.
Objective--To determine whether larkspur-derived N-(methylsuccinimido) anthranoyllycoctonine (MSAL)-type alkaloids alter heart rate and electrically evoked electromyographic (eEMG) response of the external anal sphincter (EAS) in cattle and whether these effects can be reversed by acetylcholinesterase inhibitors. Animals--12 beef heifers and 4 cows. Procedures--3 or 4 heifers were used in 1 or 2 of 7 dose-response experiments; heart rate and EAS eEMG response were assessed before and 24 hours after oral treatment with larkspur (doses equivalent to 0.5 to 15 mg of MSAL-type alkaloids/kg). In 3 subsequent experiments, 3 heifers (1 of which was replaced with another heifer in the control experiment) each received 10 mg of MSAL-type alkaloids/kg and were injected IV with physostigmine (0.04 mg/kg), neostigmine (0.04 mg/kg), or saline (0.9% NaCl) solution 24 hours later, prior to assessment. Additionally, EAS eEMG response was measured in 4 cows before and after epidural administration of 2% lidocaine hydrochloride. Results--Larkspur-treated heifers developed dose-related increases in heart rate and decreases in EAS eEMG response. Twenty-four hours after administration of MSAL-type alkaloids, neostigmine decreased heart rate but did not affect eEMG response, whereas physostigmine did not affect heart rate but caused a 2-fold increase in eEMG response. In cows, epidural anesthesia did not alter eEMG response, suggesting that transdermal stimulation of the EAS pudendal innervation did not occur. Conclusions and Clinical Relevance--In cattle, cardiac effects and muscle weakness or loss of EAS eEMG response induced by larkspur-derived MSAL-type alkaloids were reversed by neostigmine or physostigmine, respectively. Treatment with anticholinesterase inhibitors may alter the clinical effects of larkspur poisoning in cattle.
Show more [+] Less [-]Evaluation of economic effects and the health and performance of the general cattle population after exposure to cattle persistently infected with bovine viral diarrhea virus in a starter feedlot
2009
To evaluate economic effects and health and performance of the general cattle population after exposure to cattle persistently infected (PI) with bovine viral diarrhea virus (BVDV) in a feedlot. 21,743 high-risk calves from the southeastern United States. PI status was determined by use of an antigen-capture ELISA (ACE) and confirmed by use of a second ACE, reverse transcriptase-PCR assay of sera, immunohistochemical analysis, and virus isolation from sera. Groups with various amounts of exposure to BVDV PI cattle were used. After being placed in the feedlot, identified PI cattle were removed from 1 section, but PI cattle remained in another section of the feedlot. Exposure groups for cattle lots arriving without PI animals were determined by spatial association to cattle lots, with PI animals remaining or removed from the lot. 15,348 cattle maintained their exposure group. Performance outcomes improved slightly among the 5 exposure groups as the risk for exposure to BVDV PI cattle decreased. Health outcomes had an association with exposure risk that depended on the exposure group. Comparing cattle lots with direct exposure with those without direct exposure revealed significant improvements in all performance outcomes and in first relapse percentage and mortality percentage in the health outcomes. Economic analysis revealed that fatalities accounted for losses of $5.26/animal and performance losses were $88.26/animal. This study provided evidence that exposure of the general population of feedlot cattle to BVDV PI animals resulted in substantial costs attributable to negative effects on performance and increased fatalities.
Show more [+] Less [-]Existence of antibodies against bovine enterovirus in humans and various animals in Korea
2009
Park, J.H., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Kim, S.M., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Bang, M.W., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Lee, K.N., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Ko, Y.J., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Lee, H.S., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea | Shim, H.S., Gyeonggido Veterinary Service, Suwon, Republic of Korea | Cho, I.S., National Veterinary Research and Quarantine Service, Anyang, Republic of Korea
Bovine enteroviruses (BEVs) were separated into two groups, BEV-1 and BEV-2. BEVs, found in cattle worldwide, usually cause asymptomatic infections and are excreted in the feces of infected animals. Antibodies against BEV have been found in different species including human, cattle, sheep, goats, dogs, horses and monkeys in the world. This study aimed to investigate prevalence of the neutralizing antibodies for BEVs in human and animals in Korea. Antibodies against BEV-1 in humans, cattle, pigs, goats, horses and dogs were shown to be 46.8%, 48.3%, 70.6%, 11.5% and 6.3% respectively. Also, antibodies against BEV-2 were shown to be 98.7%, 68.1%, 89.2%, 59.4%, 9.4% and 96.9% respectively. We found that the neutralizing antibodies against these viruses are common in Korea. The prevalences of antibodies against BEV-1 were lower than those against BEV-2 in humans and in all animals except horses. These results showed that the BEV is considered endemic in cattle in many regions in Korea.
Show more [+] Less [-]Evaluation of the control of pathogen load by an anti-Salmonella bacterium in a herd of cattle with persistent Salmonella infection
2009
Patton, Toni G. | Sharma, Vijay K. | Carlson, Steve A.
To determine whether an anti-Salmonella bacterium is involved in control of pathogen load in persistently infected cattle herds. 24 Holstein calves experimentally infected and 39 Holstein cows naturally infected with Salmonella spp. An Escherichia coli (designated as P8E5) that possessed anti-Salmonella activity was isolated from Salmonella-negative bovine feces obtained from a herd with endemic Salmonella infection. In vitro analysis involved enumerating Salmonella enterica serovar Typhimurium coincubated with E coli P8E5. In vivo analysis involved coadministration of Salmonella spp and E coli P8E5 or an E coli control strain to neonatal Holstein calves. Fecal samples were collected on multiple days after inoculation, and quantitative PCR assay was performed by use of Salmonella-specific primers. E coli P8E5 reduced viability of Salmonella spp in vitro. Shedding of Salmonella organisms was diminished in calves administered E coli P8E5, whereas the control strain of E coli had no effect on shedding of Salmonella organisms. In this study, an E coli strain was identified that possessed bacteriocin-like activity and was able to decrease viability of Salmonella organisms in vitro and in vivo. Therefore, it is possible that this organism could be representative of native microbiota that dampen Salmonella spp in persistently infected cattle herds.
Show more [+] Less [-]Evaluation of immunohistochemical detection of prion protein in rectoanal mucosa-associated lymphoid tissue for diagnosis of scrapie in sheep
2009
Dennis, Michelle M. | Thomsen, Bruce V. | Marshall, Katherine L. | Hall, S Mark | Wagner, Bruce A. | Salman, Mo D. | Norden, Dianne K. | Gaiser, Charles | Sutton, Diane L.
To determine the suitability and estimate the sensitivity of an immunohistochemical (IHC) test for disease-associated prion protein (PrP(Sc)) in biopsy specimens of rectoanal mucosa-associated lymphoid tissue (RAMALT) for diagnosis of scrapie in sheep. 762 sheep at high risk for having scrapie and indemnified by the National Scrapie Eradication Program. The IHC test for PrP(Sc) was applied to 2 RAMALT and 2 third-eyelid biopsy specimens and a postmortem RAMALT specimen from each sheep. Results were compared with those of a reference test in which results for tissues from obex and retropharyngeal lymph nodes, tonsil, or both were considered in parallel. The reference test identified 139 sheep as having scrapie. Biopsy-related complications occurred in 3 sheep. Sensitivity of the IHC test in RAMALT ranged from 85.3% to 89.4%, depending on the anatomic location from which RAMALT was obtained. Results for the test applied to 1 RAMALT specimen were similar to results interpreted in parallel for 2 third-eyelid specimens (sensitivity, 87.0%). The proportion of inconclusive test results attributable to insufficient lymphoid follicles in biopsy specimens was lower when considering results for 2 RAMALT specimens in parallel (10.1%) than when considering results for 2 third-eyelid specimens in parallel (23.7%). Specimens of RAMALT that were inappropriately collected from an area caudal to the rectoanal interface yielded a high proportion of inconclusive results (33.3% to 50.0%). The IHC test for PrP(Sc) in RAMALT was an effective means of detecting subclinical scrapie in live, high-risk sheep.
Show more [+] Less [-]Structural implications of the EL(K/Q)(L/C)LD(A/G)DD sequence in the C-terminal cytoplasmic tail for proper targeting of anion exchanger 1 to the plasma membrane
2009
Adachi, H., Hokkaido Univ., Sapporo (Japan) | Ito, D. | Kurooka, T. | Otsuka, Y. | Arashiki, N. | Sato, K. | Inaba, M.
While the C-terminal cytoplasmic tail of anion exchanger 1 (AE1, band 3) has been reported to possess important physiological roles, including one for proper membrane trafficking, its precise characteristics remain unclear. To clarify the overall structural consequences of the conserved sequence EL(K/Q)(L/C)LD(A/G)DD, containing the core binding sequence LDADD for carbonic anhydrase II, in the C-terminal region, we analyzed the membrane expression and turnover of bovine AE1 with a series of truncation and substitution mutations in HEK293 cells. Immunofluorescence microscopy and cell-surface biotinylation demonstrated that truncation mutants missing 18 C-terminal residues targeted the plasma membrane, but the one lacking the conserved region, by truncation of 28 amino acid residues, was retained inside the cells. Substitutions of Ala for Glusup(901), Leusup(902), Leusup(905), and Aspsup(906) in the sequence E901L(K/Q)(L/C)LDADD909 of bovine AE1 or those in the corresponding murine sequence also caused intracellular retention, though these mutants had half-lives comparable to that for wild-type AE1. These data demonstrate that the conserved amino acid residues Glusup(1), Leusup(2), Leusup(5), and Aspsup(6) in the EL(K/Q)(L/C)LD(A/G)DD region have essential structural consequences in stable expression of AE1 at the plasma membrane regardless of the ability in binding to carbonic anhydrase II of this region.
Show more [+] Less [-]Radioecological investigation of food of animal origin in Belgrade environment
2009
Gordana, V., Belgrade Univ. (Serbia) | Svetlana, G. | Branislava, M. | Milan, O. | Branko, P.
The activity concentrations of sup(40)K, sup(238)U, sup(232)Th and sup(137)Cs were measured using gamma spectrometric method in different food chain samples from Serb Belgrade environment during the periods May-June 2007 and May-June 2008 year. Relatively high activities of sup(40)K and sup(137)Cs were detected in the soil. These results indicate that sup(137)Cs is present in Belgrade environment even 20 years after nuclear accident in Chernobyl. However, in the samples of feedstuffs, animal products and bio indicators (meat of wild animals and fish), activity concentrations of primordial radionuclides and sup(137)Cs were low and below the detection limits. Results of these trials have shown that investigated animal products from the natural environment around Belgrade, are radioactivity safe.
Show more [+] Less [-]In vitro propagation of rabies virus in mouse dorsal root ganglia cells
2009
Hara, Y.(Hokkaido Univ., Sapporo (Japan)) | Sunden, Y. | Ochiai, K. | Umemura, T.
Rabies virus (RV) is highly neurotropic and migrates to the neuronal soma by retrograde axonal transport from nerve terminals, after which it is taken by anterograde axonal transport to be finally released into the central nervous system (CNS) from which it disseminates, resulting in lethal encephalitis. Dorsal root ganglia (DRG) are crucial in the initial events of the infection by RV since they can act as a gate for the viral entrance into the CNS. In the present study, we examined cell tropism of RV and the roles of neuronal cytoskeletal components in the production of viral nucleoprotein (N protein) using cultured nerve cells and non-neuronal cells from DRG of newborn mice. Our in vitro study demonstrated a low propagation rate of RV in nerve cells, susceptibility of non-neuronal cells to RV, and independence of cytoplasmic synthesis of viral N protein from the neuronal cytoskeleton. The present study also suggests that Schwann cells should be considered as another possible candidate supporting RV propagation.
Show more [+] Less [-]Адаптационно-компенсаторные возможности личиночных форм цестод
2009
Dubina, I.N., Vitebsk State Academy of Veterinary Medicine (Belarus)
Determination of adaptation and compensation abilities of larval forms of cestodes (cysticercus and echinococci) was realized by means of evaluation of biochemical composition of their internal environment. There was realized the following estimation of biochemical composition of internal environment: Cysticercus tenuycollis from sheep - 34, Cysticercus tenuycollis from swine - 17, Echinococcus granulosus L. from swine - 23. Estimation of biochemical composition of custodies larvaceous forms was realized on the basis of the standard veterinary methods. Research results revealed that osmotic volumetric concentration of internal environment of custodies larval forms was lower than of osmolarity of blood serum. The average value of osmolarity of blood serum for both sheep and swine was 296,63 mmol/l. Research results showed presence of large quantity of specific lipo- and glycoproteins in custodies larva forms. Cysticercotic liquid administrated into suspended matter of microorganism Micrococcus lysadeicticus and leads to lyzing up to 5% of microbal bodies. It was possible to testify the presence of lyzing activity in liquid of larval forms of cestodes. The research results showed that the analyzed larval forms of cestodes had a lot of different and strong defense mechanisms. Adaptation and compensation abilities of larval forms of cestodes had nonspecific character and contained the following: physical mechanisms; humoral immunocompetent factors; and biochemical adaptation
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