Analysis of fenbendazole residues in bovine milk by ELISA

Fenbendazole residues in bovine milk were analyzed by ELISAs using two monoclonal antibodies. One monoclonal antibody (MAb 587) bound the major benzimidazole anthelmintic drugs, including fenbendazole, oxfendazole, and fenbendazole sulfone. The other (MAb 591) was more specific for fenbendazole, with 13% cross-reactivity with the sulfone and no significant binding to the sulfoxide metabolite. The limit of detection of the ELISA method in the milk matrix was 7 ppb for MAb 587 and 3 ppb for MAb 591. Fenbendazole was administered in feed, drench, and paste form to three groups of dairy cattle. Milk was collected immediately before dosing and then every 12 h for 5 days. The ELISA indicated that residue levels varied widely among individual cows in each group. Fenbendazole levels peaked at approximately 12-24 h and declined rapidly thereafter. Metabolites were detected at much higher levels than the parent compound, peaked at approximately 24-36 h, and declined gradually. Residue levels were undetectable by 72 h. The ELISA data correlated well with the total residues determined by chromatographic analysis, but the use of the two separate ELISAs did not afford an advantage over ELISA with the single, broadly reactive MAb 587. The ELISA method could be used to flag high-residue samples in on-site monitoring of fenbendazole in milk and is a potential tool for studying drug pharmacokinetics.     

The apparent in vivo neuromuscular effects of the δ-endotoxin of Bacillus thuringiensis var. israelensis in mice and insects of four orders

Alkaline-dissolved crystal δ-endotoxin from Bacillus thuringiensis var. israelensis (serovar H 14) was injected into mice and seven species of insects representing the orders Lepidoptera, Orthoptera, Coleoptera, Hemiptera, and Diptera. High in vivo toxicity, at 1 to 5 ppm (μg toxin/g body wet wt), was observed with mice and some insects, including some that are not sensitive to the toxin when administered orally. Neuromuscular effects were observed when the toxin was injected directly into the body cavity of the test animals. Biochemical studies suggested that different protein fragments within the crystal δ-endotoxin may be responsible for the majority of the mosquito larvacidal activity and the neurotoxic symptoms observed in larvae of Trichoplusia ni.     

Asexual Propagation of Grapevine Transmits Pierce’s Disease Pathogen (Xylella fastidiosa) to Rooted Cuttings

An objective of this study was to investigate rooting success of grape cuttings propagated from vines symptomatic of Pierce’s disease. Additional objectives were to assess if rooted cuttings could survive and produce viable plants, and determine if Xylella fastidiosa (causal agent of Pierce’s disease) could be found in rooted cuttings. In Jan. 2008, cuttings were taken from symptomatic and asymptomatic ‘Merlot’ and ‘Cabernet Sauvignon’ grapevines growing in the Hill Country and Gulf Coast regions of Texas. Six weeks after cuttings were propagated, each cutting was uprooted and evaluated for rooting and infection parameters. Cuttings were then planted in containers and held in the greenhouse to evaluate survivability. To confirm the presence of X. fastidiosa, propagated cuttings were tested by real-time polymerase chain reaction. Data indicate several rooted cuttings tested positive for X. fastidiosa and appeared viable and healthy. Therefore, vines infected with X. fastidiosa have the ability to produce asexually propagated cuttings, and potentially contaminate non-infected vineyards.     

Agent-specific responses in the cingulate cortex during economic exchanges

Interactions with other responsive agents lie at the core of all social exchange. During a social exchange with a partner, one fundamental variable that must be computed correctly is who gets credit for a shared outcome; this assignment is crucial for deciding on an optimal level of cooperation that avoids simple exploitation. We carried out an iterated, two-person economic exchange and made simultaneous hemodynamic measurements from each player's brain. These joint measurements revealed agent-specific responses in the social domain ("me" and "not me") arranged in a systematic spatial pattern along the cingulate cortex. This systematic response pattern did not depend on metrical aspects of the exchange, and it disappeared completely in the absence of a responding partner.     

Compressive myelopathy due to intervertebral disk extrusion in a llama (Lama glama).

A 12-year-old intact female llama was euthanized following acute onset of spastic tetraparesis and recumbency with inability to rise. Postmortem examination revealed caudal cervical spinal cord compression due to a mass within the ventral spinal canal arising from the C6-C7 intervertebral disk space and attached to an irregularly thickened annulus fibrosis. On histopathologic examination, the mass was composed of amorphous acellular basophilic to amphophilic material admixed with irregularly arranged collagen bundles. The amorphous material was metachromatic and contained multiple small foci of markedly vacuolated round cells, characteristic of origin from the nucleus pulposus. Severe necrosis of all white matter tracts with astrocytic reaction was present in the overlying spinal cord segment. Ascending and descending Wallerian degeneration and dissecting interstitial astrogliosis were present within white matter tracts above and below the lesion, respectively. The diagnosis was compressive myelopathy due to chronic extrusion of the nucleus pulposus of the C6-C7 intervertebral disk. To the authors' knowledge, this is the first report of intervertebral disk disease in a camelid.     

Influence of water level,hunting pressure and habitat type on crocodile abundance in the fly river drainage,Papua New Guinea

Between October 1978 and July 1980, day and night crocodile surveys were conducted at low, normal and high water levels over 2703 km of river and lakeshore in the Western and Southern Highlands provinces of Papua New Guinea. The 1353 crocodiles seen ranged between 0·18 and 2·23 animals per km.Night counts recorded 12·9 times as many crocodiles as day counts over the same area. This may indicate more nocturnal activity than occurs in other crocodilians. Unhunted areas had a greater proportion of large crocodiles than did hunted regions. As the water level rose, the ‘visible juveniles’ category decreased as a result of migration into newly flooded adjacent swamplands. The upstream range of New Guinea crocodiles on the Strickland River extended only to the Burnett River junction.There was an increase in flight distance with increasing body size and this rate of increase was over twice as large for hunted populations as for unhunted ones.     

Sward Height and a Capacitance Probe for Estimating Herbage Mass

Estimation of herbage mass is essential in pasture research and in making practical grazing management decisions. Sward height and a capacitance probe were evaluated as non-destructive measures of herbage mass at seven dates from April 16 to July 30 on continuously grazed predominantly Kentucky bluegrass ( Poa pratensis L.) pasture. Paddocks were 1 ha in size and were stocked at 3, 4 or 5 steers ha⁻¹ (average initial weight 312 kg). Four to six, sampling points were located randomly in each paddock at each date. Sward height was measured with a ruler, the vegetation in a 0.2 nr area visually designated "high" or "low" according to legume percentage, ten readings using a single capacitance probe were made and the herbage clipped. Paired data with clipped dry weight as dependent variable and height and/or the average corrected probe reading as covariates were analyzed statistically. The relationship between clipped dry weight and nondestructive measures of herbage mass was found to be linear. There was a small effect of sampling date in Spring on the relationship between destructive and non-destructive measures of herbage mass, but each of the measures, including herbage mass predicted from probe and height measurements, resulted in the same inferences being made about differences between treatments. Neither stocking rate nor small differences in percentage legume affected the relationship. Thus, sward height and capacitance probe show promise as nondestructive measures of pasture herbage mass.     

The rupture and repair of cooperation in borderline personality disorder

To sustain or repair cooperation during a social exchange, adaptive creatures must understand social gestures and the consequences when shared expectations about fair exchange are violated by accident or intent. We recruited 55 individuals afflicted with borderline personality disorder (BPD) to play a multiround economic exchange game with healthy partners. Behaviorally, individuals with BPD showed a profound incapacity to maintain cooperation, and were impaired in their ability to repair broken cooperation on the basis of a quantitative measure of coaxing. Neurally, activity in the anterior insula, a region known to respond to norm violations across affective, interoceptive, economic, and social dimensions, strongly differentiated healthy participants from individuals with BPD. Healthy subjects showed a strong linear relation between anterior insula response and both magnitude of monetary offer received from their partner (input) and the amount of money repaid to their partner (output). In stark contrast, activity in the anterior insula of BPD participants was related only to the magnitude of repayment sent back to their partner (output), not to the magnitude of offers received (input). These neural and behavioral data suggest that norms used in perception of social gestures are pathologically perturbed or missing altogether among individuals with BPD. This game-theoretic approach to psychopathology may open doors to new ways of characterizing and studying a range of mental illnesses.     

Molecular genetic and expression analysis of alpha-tocopherol transfer protein mRNA in German shepherd dogs with degenerative myelopathy

Degenerative Myelopathy (DM) is a progressive neurological disorder of the spinal cord preferentially occurring in German shepherd dogs. The pathogenesis of the disease is unknown. However, there are indications that vitamin E deficiency may be involved in the pathogenesis of DM. Therefore, we analyzed the expression and the nucleotide sequence of the canine alpha-tocopherol transfer protein (alpha Ttp) of German shepherd dogs with DM in order to determine whether a deficiency or a defect of the alpha Ttp could be a primary factor in the pathogenesis of DM, as found in human patients with Ataxia with vitamin E deficiency (AVED). The cDNA of the coding region of the canine alpha Ttp-mRNA was generated from total liver RNA using RT-PCR and 5' RACE technique. We determined the sequence of 707 out of 834 base pairs or 84.8% of the canine alpha Ttp coding region. Sequence comparison of canine alpha Ttp between affected and control dogs revealed no differences in either nucleotide or predicted amino acid sequence. Using Northern blot analysis alpha Ttp-mRNA expression was solely found in the liver of the dogs, rats and humans, while various other organs showed no alpha Ttp-mRNA expression. No significant differences in expression levels of canine alpha Ttp mRNA were found between DM and control dogs. Our data suggest that the canine alpha Ttp gene is unlikely to be involved in the pathogenesis of DM in German shepherd dogs.