DDT and sodium transport in the eel electroplaque

DDT inhibits the ATPase activity of the intact eel electroplaque. At a concentration of 10^?5M, DDT inhibited 46% of the total ATPase activity, and 10^?4M DDT inhibited 62% of the total ATPase activity and 62% of the ouabain-sensitive ATPase activity. The latter concentration of DDT reduced the rate of Na efflux from intact electroplaques and slowed the rate of recovery of the membrane potential following a large depolarization produced by carbamylcholine application. Repetitive direct stimulation of the innervated membrane at 10 Hz during the application of 10^?4M DDT produced a significant irreversible depolarization. Ouabain, 10^?4M, produced similar effects. The possible role of the inhibition of active NaK transport in producing the symptoms of DDT poisoning is discussed.     

Identification of lactoferrin and glutamate receptor‐interacting protein 1 in bovine cervical mucus: A putative marker for oestrous detection

Accurate detection of oestrus is important for artificial insemination. The aim of this study was to identify oestrous‐specific bovine cervical mucus proteins that could be used to determine the optimal time for artificial insemination. Non‐oestrous and controlled internal drug release (CIDR)‐induced oestrous‐stage mucus proteins were purified and subjected to surface‐enhanced laser desorption/ionization time‐of‐flight mass spectrometry, sodium dodecyl sulphate polyacrylamide gel electrophoresis and MALDI‐TOF/TOF. Among differentially expressed proteins, lactoferrin (LF) and glutamate receptor‐interacting protein 1 (GRIP1) showed a twofold increase during the CIDR‐induced oestrous stage compared to the levels in non‐oestrous stage in bovine cervical mucus. The RT‐PCR, Western blotting and immunohistochemistry results showed that LF and GRIP1 expression was significantly increased during the oestrous stage in the uterus. This study demonstrated that bovine LF and GRIP1 exist during the oestrous stage, but not during the non‐oestrous stage, suggesting that cervical mucus LF and GRIP1 are useful oestrous detection markers in cattle.     

Over representation of Burmese cats with diabetes mellitus

Objective To determine if Burmese cats in Queensland have an increased risk of diabetes mellitus.
Design A retrospective study of diabetic and nondiabetic cats that had blood submitted to a veterinary clinical laboratory over a 22 month study period.
Sample population 4402 cats
Procedure Cats were considered diabetic if blood glucose concentration was > 11 mmol/L and fructosamine was > 406 μmol/L or hydroxybutyrate was >1 mmol/L. Cats were grouped into Burmese and non-Burmese. Adjusted odds ratios of diabetes were calculated for breed, gender and age group amongst cats with blood glucose > 11 mmol/L.
Results Burmese cats comprised 20% of 45 diabetic cats of known breed, which was higher (P < 0.001) than among the normoglycemic reference population of 2203 cats (7% Burmese). There were more females among the diabetic Burmese (62%), but this did not differ (P > 0.05) from the Burmese reference population (45% females). In contrast, males seemed to predominate among diabetic non-Burmese (63%), although this also did not differ (P > 0.05) from the reference population (55%) or from diabetic Burmese (38% males). The majority (90%) of diabetic cats were older than 6 years, irrespective of breed (median age 12 years, interquartile range 10 to 13 years). This was higher (χ²= 8.13, P < 0.005) than among the normoglycaemic reference population, where 69% were older than 6 years.
Conclusions Burmese cats were significantly over represented among cats with diabetes mellitus. Irrespective of breed, the risk of diabetes in the study population increased with age.     

The Importance of Spatial Scale for Conservation and Assessment of Anuran Populations in Coastal Wetlands of the Western Great Lakes,USA

Distributions of pond-breeding amphibians may be influenced by habitat factors at different spatial scales. We used anuran calling surveys to investigate the association between 5 anuran species and habitat variables measured within 100, 500, 1000, and 3000 m of sampling points at 63 coastal wetlands along the US shores of Lake Michigan and Lake Huron. Stepwise logistic regression was used to create predictive models for each species at each spatial scale. Our results confirm the view that habitat variables at multiple scales influence frog distributions, but the strength of predictive models was significantly affected by the spatial scale at which habitat variables were derived. Remotely sensed habitat variables within a 3000 m radius were among the most effective predictors of occurrence for American toad (Bufo americanus), eastern gray treefrog (Hyla versicolor), spring peeper (Pseudacris crucifer), and green frog (Rana clamitans melanota). The western chorus frog (Pseudacris triseriata) was predicted most effectively by variables derived within a 500 m radius. For the most part, these anurans exhibited species-specific responses to habitat variables; however the suite of landscape-scale variables associated with urban land use appeared in all species’ regression models. Associations with landscape-scale variables coupled with well-documented habitat needs at local breeding sites suggest that conservation and assessment of frogs and toads in coastal wetlands should consider the influence of habitat variables at multiple spatial scales.     

Pain-related cerebral potentials in response to acute painful electrical stimulation in sheep

Objective To examine associations between late event-related cerebral potential amplitudes and behavioural responses to noxious electrical stimulation as an indicator of acute pain in sheep.
Design Analysis of variance for the effects of stimulus intensity on the behaviour and event-related cerebral potential variables.
Procedure Ninety-six brief constant current electrical pulse trains were presented to the front left leg of eight sheep at four intensities (2.5 to 10 mA) in a randomised order. An event-related cerebral potential and a graded flinch response were recorded for each stimulus and the 24 event-related cerebral potentials at each intensity were averaged to produce a mean waveform. Various components of this waveform were analysed and changes in these measures and the sheep's flinch response, as stimulus intensity increased, were determined.
Results Both the flinch response and some event-related cerebral potential components, that is, peak amplitudes 114 {N1}, 187 {P1}, 318 {P2} and 230 {Pm} ms after stimulus onset, were significantly affected as stimulus intensity increased.
Conclusion These corresponding behavioural and event-related cerebral potential changes indicate the usefulness of using changes in the event-related cerebral potential to measure acute pain in sheep.     

Ectomycorrhizal fungi and exogenous auxins influence root and mycorrhiza formation of Scots pine hypocotyl cuttings in vitro

We studied the ability of the ectomycorrhizal (ECM) fungi, Pisolithus tinctorius (Pers.) Coker and Couch and Paxillus involutus (Batsch) Fr. (Strain H), to produce indole-3-acetic acid (IAA) and to affect the formation and growth of roots on Scots pine (Pinus sylvestris L.) hypocotyl cuttings in vitro. Effects of indole-3-butyric acid (IBA) and the auxin transport inhibitor, 2,3,5-triiodobenzoic acid (TIBA), on rooting and the cutting-fungus interaction were also studied. Both fungi produced IAA in the absence of exogenous tryptophan, but the mycelium and culture filtrate of Pisolithus tinctorius contained higher concentrations of free and conjugated IAA than the mycelium and culture filtrate of Paxillus involutus. Inoculation with either fungus or short-term application of culture filtrate of either fungus to the base of hypocotyl cuttings enhanced root formation. Inoculation with either fungus was even more effective in enhancing root formation than treatment of the hypocotyl bases with IBA. Fungal IAA production was not directly correlated with root formation, because rooting was enhanced more by Paxillus involutus than by Pisolithus tinctorius. This suggests that, in addition to IAA, other fungal components play an important role in root formation. Treatment with 5 microM TIBA increased the rooting percentage of non-inoculated cuttings, as well as of cuttings inoculated with Pisolithus tinctorius, perhaps as a result of accumulation of IAA at the cutting base. However, the marked reduction in growth of Pisolithus tinctorius in the presence of TIBA suggests that the effects of TIBA on rooting are complicated and not solely related to IAA metabolism. The high IAA-producer, Pisolithus tinctorius, formed mycorrhizas, and the IBA treatment increased mycorrhizal frequency in this species, whereas TIBA decreased it. Paxillus involutus did not form mycorrhizas, indicating that a low concentration of IAA together with other fungal components were sufficient to stimulate formation and growth of the roots, but not the formation of ECM symbiosis.     

Efficacy and pharmacokinetics of enrofloxacin and flunixin meglumine for treatment of cows with experimentally induced Escherichia coli mastitis

The efficacy of flunixin alone and together with enrofloxacin in treatment of experimental Escherichia coli mastitis was compared using six cows. The cross-over study design was used. Pharmacokinetics of flunixin and enrofloxacin were also studied in these diseased cows. The response of each cow was similar after the first and second challenge and the individual reaction seemed to explain the severity of clinical signs. The most important predictive factor for outcome of E. coli mastitis was a heavy drop in milk yield. Treatment with enrofloxacin and flunixin enhanced elimination of bacteria, but the difference from those receiving flunixin alone was not significant. Two cows, which had received no antimicrobial treatment (Group 1), were killed on day 4 postchallenge. One cow was killed after the first and the other after the second challenge. Cows receiving combination therapy produced 0.9 L more milk per day during the study period than cows which had only received flunixin (P < 0.05). Based on our findings, antimicrobial treatment might be beneficial in the treatment of high-yielding cows in early lactation. The absorption of enrofloxacin was delayed after subcutaneous administration, the mean apparent elimination half-life being about 23 h, whereas after i.v. administration elimination t(1/2) was only 1.5 h. The majority of the antimicrobial activity in milk originated from the active metabolite, ciprofloxacin, which could be measured throughout the 120-h follow-up period after the last subcutaneous administration. No differences were present in the pharmacokinetic parameters of flunixin between treatment groups: mean elimination half-life was 5.7-6.2 h, volume of distribution 0.43-0.49 L/kg and clearance 0.13-0.14 L h/kg. No flunixin or merely traces were detected in milk: one of the three cows had a concentration of 0.019 mg/L 8 h after administration.     

Comparison of two injectable anesthetic regimes in feral cats at a large-volume spay clinic

Same‐day mass sterilization of feral cats requires rapid onset, short‐duration anesthesia. The purpose of this study was to compare our current anesthetic protocol, Telazol–ketamine–xylazine (TKX) with medetomidine–ketamine–buprenorphine (MKB). Feral female cats received either IM TKX (n = 68; 0.25 mL cat^?1; tiletamine 12.5 mg, zolazepam 12.5 mg, K 20 mg, and X 5 mg per 0.25 mL) or MKB (n = 17; M 40 µg kg^?1, K 15 mg kg^?1, and B 10 µg kg^?1). Intervals measured included time from injection to recumbency, time to surgery, duration of surgery, and time from reversal of anesthesia (TKX: yohimbine 0.50 mg cat^?1 IV; MKB: atipamezole 0.50 mg cat^?1 IM) to sternal recumbency. Following instrumentation (Vet/Ox 4403 and Vet/BP Plus 6500), physiological measurements were recorded at 5‐minute intervals, and included rectal temperature, heart rate (HR), respiratory rate (RR), SpO₂ (lingual or rectal probes), and indirect mean arterial blood pressure (MAP) (oscillometric method). Nonparametric means were compared using Mann–Whitney U‐tests. Parametric means were compared using a two‐factorial anova with Bonferroni's t‐tests. The alpha‐priori significance level was p < 0.05. Values were mean ± SD. Body weight (TKX: 2.9 ± 0.5 kg, MKB: 2.7 ± 0.7 kg), time to recumbency (TKX: 4 ± 1 minutes, MKB: 3 ± 1 minutes), time to surgery (TKX: 28 ± 7 minutes, MKB: 28 ± 5 minutes), and duration of surgery (TKX: 11 ± 7 minutes, MKB: 8 ± 5 minutes) did not differ between groups. In contrast, MKB cats required less time from reversal to sternal recumbency (TKX: 68 ± 41 minutes, MKB: 7 ± 2 minutes) and were recumbent for shorter duration (TKX: 114 ± 39 minutes, MKB: 53 ± 6 minutes). Temperature decreased during the study in both groups, but overall temperature was higher in MKB cats (38.0 ± 0.95 °C) than in TKX cats (37.5 ± 0.95 °C). RR, HR, and SpO₂ did not change during the study in either group. However, overall HR and RR were higher in TKX cats (RR: 18 ± 8 breaths minute^?1, HR: 153 ± 30 beats minute^?1) compared to MKB cats (RR: 15 ± 7 breaths minute^?1, HR: 128 ± 19 beats minute^?1). In contrast, overall SpO₂ was lower in the TKX group (90 ± 6%) compared to the MKB group (94 ± 4%). MAP was also lower in the TKX group (112 ± 29 mm Hg) compared to that in the MKB group (122 ± 20 mm Hg). However, MAP increased in the TKX group during surgery compared to pre‐surgical values, but did not change in the MKB group. The results of this study suggested that MKB might be more suitable as an anesthetic for the purpose of mass sterilization of feral female cats.