Bioequivalence Study of Two Long-acting Oxytetracycline Formulations in Sheep

Two commercially available long-acting oxytetracycline hydrochloride formulations (Primamycin LA (Pfizer) and Terralent 20% LA (İ.E. Ulagay)) were administered by the intramuscular route to 20 clinically healthy sheep at a dose of 20 mg/kg. The study was performed in a two-period crossover design. Plasma samples were analysed by high-pressure liquid chromatography. The mean maximum concentrations (C _max) was 8.00 ± 2.05 μg/mland 8.61 ± 1.42 μg/ml, respectively. The mean area under the concentration time curve (AUC) values were 154.95 ± 50.37(μg h)/ml and 161.70 ± 47.02(μg h)/ml, respectively. The 90%confidence intervals for the ratio of C _max and AUC values for the test and reference product are with in the interval 70−143% for C _max and interval 80-−125% for AUC proposed by EMEA. It was concluded that Primamycin LA and Terralent 20% LA formulations are bioequivalent in their rate and extent of drug absorbtion. Ozdemir N. and Yıldırım, M., 2006. Bioequivalence study of two long-acting oxytetracycline formulations in sheep. Veterinary Research Communications, 30(8), 929–934     

Excitatory effect of GABAergic axo-axonic cells in cortical microcircuits

Axons in the cerebral cortex receive synaptic input at the axon initial segment almost exclusively from gamma-aminobutyric acid-releasing (GABAergic) axo-axonic cells (AACs). The axon has the lowest threshold for action potential generation in neurons; thus, AACs are considered to be strategically placed inhibitory neurons controlling neuronal output. However, we found that AACs can depolarize pyramidal cells and can initiate stereotyped series of synaptic events in rat and human cortical networks because of a depolarized reversal potential for axonal relative to perisomatic GABAergic inputs. Excitation and signal propagation initiated by AACs is supported by the absence of the potassium chloride cotransporter 2 in the axon.     

Predictors of poor anthropometric status among children under 2 years of age in rural Uganda

OBJECTIVE: To assess predictors of poor anthropometric status among infants and young children.DESIGN: Cross-sectional survey.SETTING: The rural subsistence agricultural district of Hoima, western Uganda.SUBJECTS: Seven hundred and twenty children aged 0-23 months with their mothers/carers.METHODS: Participants were recruited in September 2002, using a two-stage cluster sampling methodology. A structured questionnaire was administered to mothers in their home settings. Information on health, household socio-economic status, child feeding practices and anthropometric measurement was gathered. Conditional logistic regression analysis was applied taking into account the hierarchical relationships between potential determinants of poor anthropometric status.RESULTS: The mean Z-score for weight-for-height was -0.2 (95% confidence interval (CI) -0.1, -0.7), for height-for-age was -1.1 (95% CI -1.2, -0.9) and for weight-for-age was -0.7 (95% CI -0.8, -0.6). Wasting was independently associated only with a history of fever in the 2 weeks prior to the survey (odds ratio (OR)=4.4, 95% CI 1.5, 13), while underweight was associated with a history of fever (OR=2.4, 95% CI 1.3, 4.4) and cough (OR=3.0, 95% CI 1.3, 6.8). Stunting was positively associated with a wider range of factors, including: history of a fever episode (OR=1.7, 95% CI 1.0, 2.9), lack of a latrine in the household (OR=2.7, 95% CI 1.5, 4.9), failure to de-worm children 12 months or older (OR=1.7, 95% CI 1.1, 2.8), and being born to a non-formally educated mother compared with mothers educated above primary school (OR=2.1, 95% CI 1.1, 4.0).CONCLUSIONS: In analyses guided by the hierarchical interrelationships of potential determinants of malnutrition, wasting and underweight turned out to be independently predicted by morbidity (proximal) factors. Stunting, however, was predicted by socio-economic (distal), environmental and health-care (intermediate) factors in addition to morbidity. Strategies aimed at improving the growth of infants and young children in rural communities should address morbidity due to common childhood illness coupled with environmental and socio-economically oriented measures.     

Two cases of equine abortion caused by Rhodococcus equi

Rhodococcus equi was isolated from lung, liver, spleen, and stomach content of two aborted equine fetuses of 7 and 8 months gestation from two different farms. Lesions included diffuse pyogranulomatous pneumonia with numerous Gram-positive coccobacilli within the cytoplasm of macrophages, multinucleated Langhans giant cells and neutrophils, and enhanced extramedullary hematopoiesis with megakaryocytosis within the liver and spleen. Detection of R. equi was made by bacteriology and immunohistochemistry for R. equi and VapA, the virulence factor of R. equi. R. equi and VapA were identified within the lungs of both fetuses, and its distribution correlated with lesions. Fetal lesions were similar to those observed in foals. We speculate that the fetuses contracted infection from the placenta by normal breathing movements or by swallowing of the amniotic fluid contaminated with R. equi.     

Evaluation of respiratory function by barometric whole-body plethysmography in healthy dogs

The objective of the present study was to assess the validity of barometric whole-body plethysmography (BWBP), to establish reference values, and to standardise a bronchoprovocative test to investigate airway responsiveness using BWBP in healthy dogs. BWBP measurements were obtained from six healthy beagle dogs using different protocols: (1) during three consecutive periods (3.5min each) in two morning and two evening sessions; (2) before and after administration of two protocols of sedation; (3) before and after nebulisation of saline and increasing concentrations of carbachol and histamine both in conscious dogs and in dogs under both protocols of sedation. Enhanced pause (PENH) was used as index of bronchoconstriction. Basal BWBP measurements were also obtained in 22 healthy dogs of different breeds, age and weight. No significant influence of either time spent in the chamber or daytime was found for most respiratory variables but a significant dog effect was detected for most variables. A significant body weight effect was found on tidal volume and peak flow values (P<0.05). Response to carbachol was not reproducible and always associated with side effects. Nebulisation of histamine induced a significant increase in respiratory rate, peak expiratory flow, peak expiratory flow/peak inspiratory flow ratio and PENH (P<0.05). The response was reproduced in each dog at different concentrations of histamine. Sedation with acepromazine+buprenorphine had little influence on basal measurements and did not change the results of histamine challenge. It was concluded that BWBP is a safe, non invasive and reliable technique of investigation of lung function in dogs which provides new opportunities to characterise respiratory status, to evaluate airway hyperresponsiveness and to assess therapeutic interventions.     

Contribution to the Restoration of Mixed Forests in Central Vietnam

This article investigates options for reforestation in degraded forests in Central Vietnam within the context of sustainable forestry and presents a forest management plan for the forests around the community of Phong My. In the past, the area was damaged during the war between Vietnam and the United States and after that by overcutting. Forests have gradually been degraded and now they are replaced by plantations of fast-growing Acacia (Acacia mangium). After final harvests, the stand remnants are burnt and the burnt area is again regenerated via artificial regeneration of Acacia. Here, we propose several mixtures in which Acacia stands can be augmented with other tree species. A proposed system of afforestation and subsequent management is given here with the goal of encouraging mixed species, multiple cohort stands, and disincentivizing the method of slash-and-burn. The proposed afforestation patterns were also used to calculate the future number of seedlings required to enable the enlargement of quality forests at the expense of degraded ones.     

Co-expression of the Bcl-xL antiapoptotic protein enhances the induction of Th1-like immune responses in mice immunized with DNA vaccines encoding FMDV B and T cell epitopes

Foot-and-mouth disease (FMD) is one of the most devastating animal diseases, affecting all cloven-hoofed domestic and wild animal species. Previous studies from our group using DNA vaccines encoding FMD virus (FMDV) B and T cell epitopes targeted to antigen presenting cells, allowed demonstrating total protection from FMDV homologous challenge in those animals efficiently primed for both humoral and cellular specific responses (Borrego et al. Antivir Res 92:359-363, 2011). In this study, a new DNA vaccine prototype expected to induce stronger and cross-reactive immune responses against FMDV which was designed by making two main modifications: i) adding a new B-cell epitope from the O-serotype to the B and T-cell epitopes from the C-serotype and ii) using a dual promoter plasmid that allowed inserting a new cistron encoding the anti-apoptotic Bcl-xL gene under the control of the internal ribosomal entry site (IRES) of encephalomyocarditis virus aiming to increase and optimize the antigen presentation of the encoded FMDV epitopes after in vivo immunization. In vitro studies showed that Bcl-xL significantly prolonged the survival of DNA transfected cells (p?<?0.001). Accordingly, vaccination of Swiss out-bred mice with the dual promoter plasmid increased the total IgG responses induced against each of the FMDV epitopes however no significant differences observed between groups. The humoral immune response was polarized through IgG2a in all vaccination groups (p?<?0.05); except peptide T_3A; in correspondence with the Th1-like response observed, a clear bias towards the induction of specific IFN-γ secreting CD4⁺ and CD8⁺ T cell responses was also observed, being significantly higher (p?<?0.05) in the group of mice immunized with the plasmid co-expressing Bcl-xL and the FMDV B and T cell epitopes.     

Relationship of Echocardiographic Measurements and Velocity at Maximum Heart Rate Measured During Prerace Training Period in Thoroughbred Horses

The objective of this study was to investigate in Thoroughbreds, the relation between the development of the heart at prerace period and the velocity at maximum heart rate (VHRmax) between the 24th and 28th month before starting to race. Twenty-one Thoroughbreds (11 female, 10 male) were used in this study. The echocardiographic data were obtained from the short-axis view in guided M-mode, at 4-month intervals until the 24th month after birth. The VHRmax was measured monthly from the 24th to the 28th month by E-Trakka. Linear regression analyses were performed between echocardiographic parameters and VHRmax values at 24 and 28 months after birth. The results indicated that left ventricular internal diameter in diastole at 12 months (LVIDD₁₂) tended to be negatively correlated with VHRmax measured at the 24th month (P = .098). However, ejection fraction (EF₁₂) (P = .061) and fractional shortening (FS₁₂) (P = .056) values tended to be positively correlated with VHRmax measured at the 24th month (VHRmax₂₄). There was a tendency toward negative correlation between interventricular septal thickening percentage (IVST%) measured 1 month after birth and VHRmax measured at the 28th month (VHRmax₂₈) (P = .079). In contrast, there were positive correlations between mean wall thickness of 4 months (MWT₄), relative wall thickness of 4 months (RWT₄), and VHRmax₂₈ (P < .05). EF₁₆ and FS₁₆ tended to be correlated with VHRmax₂₈. Furthermore, EF and FS parameters measured in 20 months after birth (EF₂₀ and FS₂₀) were correlated with VHRmax₂₈ (P < .05). There was a tendency toward a positive correlation between the left ventricular muscle mass of horses at 24 months of age (LVM₂₄) and VHRmax₂₈ (P = .097). In addition, mean wall thickness of 24 (MWT₂₄) months and relative wall thickness of 24 months (RWT₂₄) were significantly correlated with VHRmax₂₈ (P < .05). In this study, we observed a relationship between some echocardiographic parameters measured during developmental period and VHRmax measured during prerace training period. Because VHRmax is related to athletic potential, echocardiographic parameters measured at early ages may be used as selection criteria.     

Accuracy and reliability of mastitis detection with electrical conductivity and milk colour measurement in automatic milking

Abstract

Detection of mastitis and reliability of alarms were evaluated in eight herds with automatic milking. Herds were visited once to gather milk samples and the farmers followed up alarms for 15 to 30 days. Sensitivity of detecting quarters with SCC over the threshold value of 200,000 or 1,000,000 cells/ml was 18.0 to 42.9% in Group A, based on electrical conductivity (EC) and 5.5 to13.0% in Group B, based on EC and milk colour. Specificity was over 97.0%. In Group A, 6/17 of the EC alarms were false positives. None of the seven EC alarms in Group B was false positive. On the day that the farmer observed clinical mastitis, more than half of the quarters received alarms, but only milk from some quarters was automatically diverted. In total 58.4% (Group A) and 26.8% (Group B) of cows had alarms based on EC, and 84.1% (<20% true positives) and 12.0% (60–90% true positives) had alarms based on milk yield or milk colour during the follow-up period. The number of alarms was halved in Group A when a running average was applied to the algorithm of EC. The proportion of true positives simultaneously increased from 30% to 60%. In Group B, the number of alarms was almost doubled with algorithm manipulation, but the proportion of true positives declined from >80% to >70%.     

Physical and land-cover variables influence ant functional groups and species diversity along elevational gradients

Of particular importance in shaping species assemblages is the spatial heterogeneity of the environment. The aim of our study was to investigate the influence of spatial heterogeneity and environmental complexity on the distribution of ant functional groups and species diversity along altitudinal gradients in a temperate ecosystem (Pyrenees Mountains). During three summers, we sampled 20 sites distributed across two Pyrenean valleys ranging in altitude from 1,009 to 2,339 m by using pitfall traps and hand collection. The environment around each sampling points was characterized by using both physical and land-cover variables. We then used a self-organizing map algorithm (SOM, neural network) to detect and characterize the relationship between the spatial distribution of ant functional groups, species diversity, and the variables measured. The use of SOM allowed us to reduce the apparent complexity of the environment to five clusters that highlighted two main gradients: an altitudinal gradient and a gradient of environmental closure. The composition of ant functional groups and species diversity changed along both of these gradients and was differently affected by environmental variables. The SOM also allowed us to validate the contours of most ant functional groups by highlighting the response of these groups to the environmental and land-cover variables.