Evaluation of weight loss in canine cancer bearing patients undergoing radiation therapy

Critical weight loss, as defined by ≥5% decrease in body weight, has been associated with increased morbidity and mortality in human patients with cancers of the head and neck. Weight loss has anecdotally been reported to occur frequently in veterinary patients undergoing radiation therapy and is hypothesized to be more severe in patients with cancers of the head and neck, along with those hospitalized during radiation therapy. The primary objective of this retrospective study was to evaluate the occurrence of critical weight loss in canine cancer bearing patients undergoing either definitive or palliative radiation protocols and to determine if weight changes were associated with radiation toxicity, tumour location or patient hospitalization status. Data from 47 dogs who underwent definitive and 43 dogs who underwent palliative radiation protocols at the University of Tennessee were included for analysis. Dogs were categorized based on tumour location (head/neck or other), hospitalization status (boarded or non‐boarded) and radiation toxicity score. Weight recorded at the start of treatment, midway through treatment and at the final treatment was used for analysis. No significant differences were found in regard to weight change over time, location or hospitalization status when evaluated for both protocols. Overall, 5/90 dogs (5.5%) lost 5% or more of their body weight during therapy, and 7/90 dogs (7.7%) gained 5% or more of their body weight. The results of the current study suggest that critical weight loss occurs in a small percentage of canine patients undergoing radiation therapy, contrary to what is often anecdotally reported.     

Population dynamics and biological control of European grapevine moth (Lobesia botrana: Lepidoptera: Tortricidae) in Albania using different strains of Bacillus thuringiensis

This work describes the results of an experiment conducted in a vineyard in Durres, Albania from 2004 to 2006, to study the efficacy of two strains of Bacillus thuringiensis Berliner, vars kurstaki and aizawai, against the moth Lobesia botrana Denis & Schiffermüleler (Lepidoptera: Tortricidae), a major pest of grapevines. The experimental results revealed that the two strains were significantly more effective than the control, with var. aizawai being more effective than var. kurstaki. Bacillus thuringiensis (Bt) provided better protection of the bunches from the second generation compared to the third one showing the short persistence of action of the active ingredient. The high degree of efficacy supported a role for Bt in grapevine moth management. Our study also provided insights into the population dynamics of the European grapevine moth under Albanian climatic conditions. Despite the necessity for the pheromone traps to indicate the start of the flight period, the experiments confirmed the lack of a correlation between the population dynamics and the level of damage by the pest. Pheromone trapping can offer very useful indications regarding the start of the flight period of each generation and its duration but not on the severity and incidence of the pest.     

Influence of dipping practices on the seroprevalence of babesiosis and anaplasmosis in the foot-and-mouth disease buffer zone adjoining the Kruger National Park in South Africa

A serological survey of bovine babesiosis and anaplasmosis was conducted in the foot-and-mouth disease buffer zone surrounding the Kruger National Park in South Africa between 2001 and 2003 to determine whether the withdrawal of government-subsidized dipping in certain regions had affected the seroprevalence of these tick-borne diseases. Seroprevalence of Anaplasma marginale and Babesia bovis increased during the study period. This increase was greater in Limpopo Province where farmers had to supply their own acaricide than in Mpumalanga Province where dipping materials were provided by the local Veterinary Services. The number of animals testing positive for B. bigemina decreased in both provinces during the study period, which was attributed to possible vector displacement rather than more effective tick control measures. Responses to a questionnaire on ticks and tick-borne diseases revealed local knowledge on the subject to be highly variable and sometimes incorrect.     

植物育种模拟的原理和应用

传统植物育种很大程度上依赖于表型选择和育种家的经验，分子生物学积累的大量遗传数据使得在基因水平上进行目标性状的选择成为可能，但是由于缺乏必要的工具，大量的遗传信息尚未在育种中得以有效利用。模拟方法可以利用各类遗传信息，在育种家进行田间试验之前，对杂交组合的表现、后代选择效果以及整个育种过程进行模拟，提出最佳的亲本选配、杂交和后代选择策略，从而提高常规育种的预见性和效率。本文介绍育种模拟的一些基本原理，包括遗传模型的构建、杂交类型和选择方法的定义等，概述育种模拟工具QuLine的基本功能及其在育种方法的比较、利用已知基因信息的亲本选配和设计育种等方面的应用。模拟方法通过定义复杂的遗传模型和育种方法实现对育种过程的模拟，在更真实的情形下比较不同育种方法的优劣、预测不同亲本杂交后代的表现，从而为育种家有效利用大量的分子信息和遗传数据提供了手段。     

Soil microbial diversity of four German long-term field experiments

Abstract

The understanding of agro-ecosystems is the key to estimating the influence of long-term agricultural production methods on the environment. The present study aimed to improve the knowledge of functional and structural soil microbial diversity influenced by differentiated fertilization at four German long-term field experiments. Soil microbial biomass, β-glucosidase, protease, alkaline phosphatase, DMSO-reduction and TTC-dehydrogenase were evaluated in soils from three different fertilizer treatments (control, farmyard manure, mineral fertilizer) at four sites (Lauterbach, Bad Lauchstädt, Halle, Thyrow). Profiles of 29 identified phospholipid fatty acids were used for the evaluation of structural diversity. The results obtained showed that fertilization applied over several decades or even more than a century has led to distinct alterations of the soil ecosystem. There was a clear separation of the sites by microbial biomass and metabolic activities into dependence of soil properties and fertilization treatments. In contrast to the control, microbial biomass and enzyme activities of the FYM soils increased more strongly than in the NPK plots. The results of PLFA analyses indicate that the community of the autochthonous microflora has differently changed among sites and fertilizer application. Principle component analyses revealed that bacteria especially Gram-positive bacteria and eukaryotes were responsible for these differences.     

Field trial of six serological tests for bovine brucellosis

Serum agglutination (SAT), complement fixation (CFT), indirect ELISA (iELISA), competitive ELISA (cELISA), Rose Bengal (RBT) and EDTA-modified agglutination (EDTA) tests were used in parallel on serological samples from 19,935 cattle in 301 herds. The study herds were selected according to putative exposure to Brucellaabortus with cases defined by bacteriological culture or test agreement. No single test identified all infected cattle and, at diagnostic thresholds, relative sensitivity was highest in the iELISA (67.9%) or RBT (78.1%), using bacteriological culture or test agreement, respectively, to define cases. As screening tests, the relative sensitivity of the SAT was highest (75.9% by culture or 84.9% by test agreement), with an optimal threshold of 31 IU. The relative specificity of the diagnostic tests ranged from 99.6% (SAT 31IU) to 100% (iELISA, RBT and CFT). The trial confirmed the value of the SAT as a screening test and the value of parallel testing.     

Primary isolation of Mycobacterium bovis from bovine tissues: conditions for maximising the number of positive cultures

In studies of Mycobacterium bovis infection in animals a definitive diagnosis requires the isolation of the organism. However, the optimum conditions for the primary isolation of M. bovis have not been determined. The aim of this study was to determine for primary isolation of M. bovis, (a) the incubation time required to achieve maximum sensitivity (i.e., the number of positive samples identified), (b) the effect of decontaminants on bacterial growth rates, and (c) the influence of media and the number of slopes of media on the number of positive samples detected. Two agar-based media, modified Middlebrook 7H11 (7H11) and tuberculosis blood agar (B83), and an egg-based medium, Stonebrink's (SB) were compared. Three decontaminants, 2% (w/v) sodium hydroxide (NaOH), 0.75% (w/v) and 0.075% (w/v) cetylpyridinium chloride (CPC, also called hexadecylpyridinium chloride, HPC) and 0.5% (w/v) benzalkonium chloride (BC) were evaluated against treatment with sterile distilled water. The inoculated media slopes were incubated for up to 15 weeks. Colonies first appeared after 2 weeks on all media types and 75% of positive slopes were identified by 8 weeks. An incubation time of 15 weeks was required to identify all positive samples. The slowest growth was associated with inocula that contained the fewest viable bacilli. The time to the appearance of colonies was influenced by medium type: the median time to detection of colonies was 28 days on 7H11 and B83, and 36 days on SB. However, SB returned the greatest number of positive samples. Decontamination procedures increased the minimum incubation time required to detect positive cultures, probably due to the toxic effect of the decontaminants. Increasing the number of inoculated slopes resulted in an increased number of positive samples and a decreased time to the detection of colonies. Overall, the detection of M. bovis was significantly influenced by the choice of media, the decontaminant and the duration of incubation of cultures.     

Cross-sectional survey of owner knowledge and husbandry practices, tack and health issues affecting working horses in Lesotho

Reasons for performing study: To establish baseline parameters of equine health, owner knowledge and husbandry practices and tack against which benefits to local horses arising from an equine charity's training programme in Lesotho could be measured. Objectives: To describe and investigate associations between owner knowledge and equine husbandry practices, horse health and tack‐related parameters prior to the start of the training programme. Methods: A cross‐sectional survey was undertaken in the catchment area of students attending the first training course. Owners from randomly selected villages were interviewed about horse care using a standardised, structured questionnaire, administered face to face in local language. Horses were clinically examined and tack assessed according to standardised protocols. Results: Clinical examinations were performed on 312 horses and 287 owners were interviewed. Owners had variable knowledge of equine husbandry and limited understanding of appropriate primary and preventive healthcare. Equine health problems identified included ecto‐ and endoparasite infestation, mouth lesions, overgrown and unbalanced feet and tack‐associated wounds. The majority of tack was in poor condition, dirty and ill‐fitting. With the exception of below‐average body condition score, no associations were found between key adverse horse‐related clinical findings and owners reporting their horse as being ‘unhealthy’. Conclusions: Working horses in Lesotho have a range of physical problems, many of which could be ameliorated through targeted owner education. With limited access to veterinary advice and scarce resources, improved availability of affordable local equine trade skills is key to improving equine health. Potential relevance: Findings could be used to inform and direct training programmes to maximise benefits to equine health and to serve as a baseline against which to monitor effects of educational and other interventions.