Novel, cyclic heat dissipation method for the correction of natural temperature gradients in sap flow measurements. Part 1. Theory and application

Natural temperature gradient (NTG) can be a significant problem in thermal sap flow measurements, particularly in dry environments with sparse vegetation. To resolve this problem, we propose a novel correction method called cyclic heat dissipation (CHD) in its thermal dissipation probe (TDP) application. The CHD method is based on cyclic, switching ON/OFF power schema measurements and a three-exponential model, extrapolating measured signal to steady state thermal equilibrium. The extrapolated signal OFF represents NTG, whereas the extrapolated signal ON represents standard TDP signal, biased by NTG. Therefore, subtraction of the OFF signal from the ON signal allows defining the unbiased TDP signal, finally processed according to standard Granier calibration. The in vivo Kalahari measurements were carried out in three steps on four different tree species, first as NTG, then as standard TDP and finally in CHD mode, each step for ～1-2 days. Afterwards, each tree was separated from its stem following modified Roberts' (1977) procedure, and CHD verification was applied. The typical NTG varying from ～0.5 °C during night-time to -1 °C during day-time, after CHD correction, resulted in significant reduction of sap flux densities (J(p)) as compared with the standard TDP, particularly distinct for low J(p). The verification of the CHD method indicated ～20% agreement with the reference method, largely dependent on the sapwood area estimate. The proposed CHD method offers the following advantages: (i) in contrast to any other NTG correction method, it removes NTG bias from the measured signal by using in situ, extrapolated to thermal equilibrium signal; (ii) it does not need any specific calibration making use of the standard Granier calibration; (iii) it provides a physical background to the proposed NTG correction; (iv) it allows for power savings; (v) it is not tied to TDP, and so can be adapted to other thermal methods. In its current state, the CHD data processing is not yet fully automated.     

Host and environmental reservoirs of infection for bovine digital dermatitis treponemes

Bovine digital dermatitis (BDD) is a global infectious disease causing lameness of cattle and is responsible for substantial animal welfare issues and economic losses. The causative agents are considered to be spirochetal bacteria belonging to the genus Treponema, which have consistently been identified in BDD lesions worldwide. One potential means of controlling infection is the disruption of transmission; however, the infection reservoirs and transmission routes of BDD treponemes have yet to be elucidated. To address these issues, we surveyed for evidence of BDD treponeme presence in the dairy farm environment, in bovine tissues and in bovine gastrointestinal (GI) tract contents. A total of 368 samples were tested using PCR assays specific for each of three currently recognised, isolated phylotypes of BDD treponemes. All environmental samples, together with insects and GI tract content samples were negative for BDD treponeme DNA from the three phylotypes. However, we identified BDD treponemes in two non-pedal bovine regions: the oral cavity (14.3% of cattle tested) and the rectum (14.8% of cattle tested). Whilst only single phylotypes were detected in the oral cavity, two of the rectal tissues yielded DNA from more than one phylotype, with one sample yielding all three BDD treponeme phylotypes. Whilst it might be considered that direct skin to skin contact may be a major transmission route of BDD treponemes, further studies are required to characterise and determine the potential contribution of oral and rectal carriage to BDD transmission.     

Effects of Ω-3 (n-3) Fatty Acid Supplementation on Insulin Sensitivity in Horses

The objective of this study was to examine the effects of dietary ω-3 fatty acid supplementation on insulin sensitivity (SI) in horses. Twenty-one mares were blocked by age, body weight (BW), and body condition score (BCS) and randomly assigned to one of three dietary treatments. Treatments consisted of (1) 38 g of n-3 fatty acids via fish and algae supplement and diet (MARINE), (2) 38 g of n-3 fatty acids via a flaxseed meal from the supplement and diet (FLAX), and (3) control (CON) no supplemental fatty acid. Treatments were supplemented for 90 days. Frequent sampling intravenous glucose tolerance tests were performed on days 0, 30, 60, and 90. Blood samples were analyzed for glucose and insulin. The minimal model was applied for the glucose and insulin curves using MinMod Millennium. SI increased 39% (P < .007) across all treatment groups. Acute insulin response to glucose decreased 22% (P < .006) between days 30 and 60 and increased (P = .040) again at day 90. Disposition index (combined SI and β pancreatic response) increased (P = .03) by 53% in the MARINE- and 48% in the FLAX-supplemented horses and did not change with time in the CON group. In insulin-resistant mares, MARINE- and FLAX-treated horses had an increase in SI (P = .09). It would be interesting to test this supplement in a larger group of insulin-resistant horses. If proven effective, supplementation with ω-3 fatty acids would help to reduce problems associated with insulin resistance in horses.     

A Case of Bronchioloalveolar Carcinoma in a Mare

A case of pulmonary carcinoma in a 23-year-old Quarterhorse mare is described. On physical examination, depression, poor body condition, tachypnea, bilateral serosanguineous nasal discharge and a wide area of reduced breath sounds in association with the right hemithorax were detected. Laboratory evaluation showed leukocytosis with neutrophilia and lymphopenia, hyperfibrinogenemia, hyperprotidemia, hypoalbuminemia, increased beta 2 and gamma globulin fractions, hypoxemia, and normocapnia. Radiography and thoracic ultrasonography revealed a large rounded mass extending from the 9th to the 14th right intercostal space, where neither bronchial nor vascular structures were detectable. Endoscopy showed a large amount of serosanguineous fluid within the tracheal lumen and a mass of reddish soft tissue completely obliterating the right caudal lobar bronchus. Histopathology of the endobronchial mass and of the transthoracic ultrasound-guided biopsy samples was consistent with a primary pulmonary epithelial tumor. Due to worsening of the clinical condition, the mare was euthanized. Postmortem examination confirmed the presence of a large 30-cm mass located in the right caudal pulmonary lobe, characterized by epithelial cells arranged in papillary projections and alveolar structures, findings consistent with bronchioloalveolar carcinoma.     

Biological indicators for evaluating soil quality improvement in a soil degraded by erosion processes

Journal of Soils and Sediments - Erosion is one of the main soil degradation problems. It diminishes soil biological activity and therefore its quality. The aim of the study was to evaluate if the...     

Pesticide contamination of the upper Elbe River and an adjacent floodplain area

Journal of Soils and Sediments - Pesticide contamination of river waters is a global problem, and therefore, authorities regularly monitor the water quality status. Especially, flood events might...     

Qualitative and quantitative evaluation of coprological and serological techniques for the diagnosis of fasciolosis in cattle

The objectives of this study were (1) to evaluate available coprological and serological tests for detection of Fasciola hepatica infection in field conditions, (2) to investigate if the season when samples were collected affects the interpretation of the test results, and (3) to evaluate if the test results are associated with the level of infection. During weekly visits to an abattoir, the whole liver, a rectal faecal sample and a blood sample were collected from 100 cows in two seasons each ("spring"=February-May 2006 and "autumn"=October-December 2006). A sedimentation-flotation technique on 4g (SF 4g) or 10g (SF 10g) of faeces, a copro-antigen ELISA and two indirect serum F. hepatica ELISAs (excretory-secretory (ES) and Pourquier ELISA) were performed and the test results were compared with the presence of infection and worm counts at liver necropsy. Over both seasons the sensitivity (Se) and specificity (Sp) were for the SF 4g 43% and 100%, for the SF 10g 64% and 93%, for the copro-antigen ELISA 94% and 93%, for the ES ELISA 87% and 90% and for the Pourquier ELISA 88% and 84%. Significant between-season differences (P<0.05) were observed in the sensitivities of the two serological ELISAs: whereas the Pourquier ELISA had a higher sensitivity in spring than in autumn, the opposite was true for the ES ELISA. There were no significant between-season differences in the specificity for any of the tests. The test results of the SF 4g, copro-antigen ELISA and ES ELISA were associated with the level of infection of the animal. Given a positive test result of the SF 4g it is at least 11 times more likely that the animal is carrying a heavy infection (>10 flukes) than that is free of infection or lightly infected (< or = 10 flukes). Weak ( approximately 0.3) and moderate ( approximately 0.6) correlations were observed within infected animals of level of infection with ES and copro-antigen ELISA results, respectively.     

Antibody response to an anti-rabies vaccine in a dog population under field conditions in Bolivia

Rabies remains an important public health issue in Bolivia, South America. Public concern and fears are most focussed on dogs as the source of rabies. The objective of the present study was to assess immunity of an inactivated suckling mouse brain vaccine against canine rabies used for the official vaccination campaigns under field conditions in an endemic area of rabies in Bolivia. A total of 236 vaccinated and 44 unvaccinated dogs in Santa Cruz de la Sierra, selected using stratified random sampling, were investigated in order to obtain owned dog characteristics and antibody titres against rabies in April 2007. The proportion of vaccinated dogs with an antibody titre exceeded the protection threshold value of 0.5 EU/ml was 58% [95% confidence intervals (CI): 52-65], indicating that vaccination is likely to elicit an antibody response (odds ratio 6.3, 95% CI: 1.2-11.5). The range of geometric mean of antibody titre for vaccinated dogs (0.89 EU/ml; 95% CI: 0.75-1.04) was considered to meet the minimal acceptable level indicating an adequate immune response to the vaccine. However, the titre level was not satisfactory in comparison with the results from other field investigations with inactivated tissue culture vaccines. It is recommended for public health authorities to (1) consider modernizing their vaccine manufacturing method because the level of immunity induced by the current vaccine is comparably low, (2) conduct frequent vaccination campaigns to maintain high levels of vaccination coverage, and (3) actively manage the domestic dog population in the study area, which is largely responsible for rabies maintenance.     

The effects of starter microbiota and the early life feeding of medium chain triglycerides on the gastric transcriptome profile of 2-or 3-week-old cesarean delivered piglets

Background: The stomach is an underestimated key interface between the ingesta and the digestive system, affecting the digestion and playing an important role in several endocrine functions. The quality of starter microbiota and the early life feeding of medium chain triglycerides may affect porcine gastric maturation. Two trials(T1, T2) were carried out on 12 and 24 cesarean-delivered piglets(birth, d0), divided over two microbiota treatments, but slaughtered and sampled at two or three weeks of age, respectively. All piglets were fed orally: sow serum(T1) or pasteurized sow colostrum(T2) on d0; simple starter microbiota(Lactobacillus amylovorus, Clostridium glycolicum and Parabacteroides spp.)(d1-d3); complex microbiota inoculum(sow diluted feces, CA) or a placebo(simple association, SA)(d3-d4) and milk replacer ad libitum(d0-d4). The The T1 piglets and half of the T2 piglets were then fed a moist diet(CTRL); the remaining half of the T2 piglets were fed the CTRL diet fortified with medium chain triglycerides and 7% coconut oil(MCT). Total m RNA from the oxyntic mucosa was analyzed using Affymetrix?Porcine Gene array strips. Exploratory functional analysis of the resulting values was carried out using Gene Set Enrichment Analysis.Results: Complex microbiota upregulated 11 gene sets in piglets of each age group vs. SA. Of these sets, 6 were upregulated at both ages, including the set of gene markers of oxyntic mucosa. In comparison with the piglets receiving SA, the CA enriched the genes in the sets related to interferon response when the CTRL diet was given while the same sets were impoverished by CA with the MCT diet.Conclusions: Early colonization with a complex starter microbiota promoted the functional maturation of the oxyntic mucosa in an age-dependent manner. The dietary fatty acid source may have affected the recruitment and the maturation of the immune cells, particularly when the piglets were early associated with a simplified starter microbiota.