Avian tuberculosis of zoonotic importance at a zoo on the Bogotá Andean plateau (Sabana), Colombia

Given that exposure to captive wild animals at circuses or zoos can be a source of zoonotic infection, a case and control study was carried out with a collection of exotic fowl at a zoo in Bogotá, Colombia. The presence of Mycobacterium avium-II was directly related to the death of birds kept in the original enclosure, and of 50% of a group of sentinel birds. Failure to detect the organism in a control group of birds outside the enclosure indicated that the infection was limited to the original enclosed area. We demonstrated that M. gordonae-IV was disseminated in all organs from 1 bird with macroscopic granulomatous lesion, a finding which has not been reported previously. We emphasize the importance of establishing handling norms to reduce the risk of zoonotic transmission.     

Genetic analysis of the response of linseed (Linum usitatissimum L.) somatic tissue to in vitro cultivation

The response of linseed somatic tissue to in vitro cultivation can be improved if the gene action involved is known. Nine homozygous lines, seven F₁ and fifty F₂ plants were cultivated in MS basal medium with 0.1 mg/l BAP. Callogenesis and regeneration analyses were done using a random model in order to separate environmental and genotypic effects at 10, 20 and 30 days after culture initiation. Genetic variability for callogenesis and regeneration was observed, that could be used in a breeding program. The appropriate period for the evaluation of callogenesis was at 20 days after culture initiation. For regeneration, this moment would depend on the selection criterion adopted. To select genotypes on the basis of earliness in shooting at 10 days would be preferable, while for ability of producing shoots, 30days would be more suitable. For both characters the analyses of genetic action indicated that, non-additive effects were involved in the culture response, however the expression of callogenesis and regeneration ability had different genetic basis. This revised version was published online in August 2006 with corrections to the Cover Date.     

Water use efficiency and crop coefficients of dry season oilseed crops

Eastern India receives higher average annual rainfall (1000–2000 mm) but 80% of it occurs within the June–September (rainy season), whereas the winter season (November–March) is dry. Due to a shortage of soil moisture, most rainfed areas of the region remain fallow during the winter season and cultivation (mainly rice) is confined to the rainy season only (June–September). To explore the possibility of double cropping in the rainfed rice areas, three oilseed crops, viz., linseed (Linum usitatissimum L.), safflower (Carthamous tinctorious L.), mustard (Brassica juncea L.), were grown in a representative rainfed area of eastern India, i.e. Dhenkanal, Orissa, during the dry/winter season by applying irrigation water at phonological stages. Study revealed that with three supplemental irrigations, the highest WUE was achieved by safflower followed by linseed with the mean values being 3.04 and 2.59 kg ha⁻¹ mm⁻¹, respectively. Whereas, with one irrigation, the highest water use efficiency (WUE) was achieved for safflower (1.23 kg ha⁻¹ mm⁻¹) followed by linseed (0.93 kg ha⁻¹ mm⁻¹). Of the three crops studied, safflower withdrew maximum water followed by mustard and crops were shown to use 90–105 mm more water than linseed. With three irrigations, average maximum rooting depths were 1.66, 1.17 and 0.67 m for safflower, mustard and linseed, respectively, which were 13.5, 10.6 and 11.4% higher than for single irrigated crops because of more wet sub soils and decrease of soil strength. The crop growth parameters like leaf area, dry biomass were also recorded with different levels of irrigation. The research work amply revealed the potential of growing these low water requiring oilseed crops in rice fallow during dry/winter season utilizing limited irrigation from harvested rainwater of rainy season. Crop coefficients (K_c) of three winter season oilseed crops were derived using field water balance approach. Study showed that LAI was significantly correlated with K_c values with the R² values of 0.91, 0.89 and 0.94 in linseed, safflower and mustard, respectively. When LAI exceeded 3.0, the K_c value was 1 in safflower and mustard whereas in linseed corresponding LAI was 2.5. Study revealed that the K_c values for the development and mid season stage were slightly higher to that obtained by the procedure proposed by FAO, which might be due to local advection.     

Rugged LC-MS/MS survey analysis for acrylamide in foods

The described liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the detection of acrylamide in food entails aqueous room temperature extraction, SPE cleanup, and analysis by LC-MS/MS. The method is applicable to a wide variety of foods. [(13)C(3)]acrylamide is the internal standard. The limit of quantitation is 10 ppb (microg/kg). Data were obtained in duplicate from >450 products representing >35 different food types. The variability in analyte levels in certain food types suggests that it may be possible to reduce acrylamide levels in those foods.     

Effects of harvester behavior on population growth rate affects sustainability of ginseng trade

When long-term, intense levels of harvest nearly extirpated Chinese ginseng (Panax ginseng C. Meyer) in the early 18th century, commercial harvest of American ginseng (P. quinquefolius L.) began and large quantities of the roots were exported to East Asia. Annual export figures have fallen over the past 200 years, but demand for wild American ginseng has not abated. Persistent harvest of long-lived, slow-maturing species can have negative impacts on population growth rates, yet those closest to wild resources are often in a position to be the best stewards of that resource. This study explored the consequences of different harvester behaviors on the population dynamics of American ginseng. Drawing on known behaviors, we developed three harvester ‘types’ and ran demographic simulations on wild ginseng populations, partitioning the sources of differences in population growth rates using a life table response experiment (LTRE). The simulations showed that ignoring size class limits and harvest season onset dates dramatically affected population growth rates. Existing laws in many states are not adequate to protect wild ginseng populations. A stewardship-oriented harvester, who delays harvest onset by two weeks, self-limits harvest intensity and plants ginseng seeds at the time of harvest can reverse declining population growth rates.     

Dynamics of humic fractions and microbial activity under no-tillage or reduced tillage,as compared with native pasture (Pampa Argentina)

Humic fractions, arginine ammonification and soil respiration were monitored in spring, summer and autumn 1999 in natural pasture soil and in no-tillage or reduced-tillage soil under maize. The Typic Argiudoll soils, typical of the Argentine rolling pampa, can be structurally unstable, particularly when conventionally tilled, a form of soil management affecting the humification process. The no-tillage soil had a lower content of fulvic acids than the reduced-tillage soil in spring and summer, probably because the humification process was favored by residue management in no-tillage soil, with a significant increase in the most stable fraction. Both arginine ammonification and CO₂ were significantly correlated with the humic acids and humin contents. No significant correlation was found with fulvic acids,probably due to the lability and high variability of this fraction. A high correlation was found between arginine ammonification and CO₂. The highest index values were generally observed in natural pasture soil, whereas no-tillage soils showed a higher index value than reduced-tillage soils throughout, confirming the hypothesis that humification is more intense in the presence of organic residues.     

Characterization of epididymal and testicular histologic lesions and use of immunohistochemistry and PCR on formalin-fixed tissues to detect Brucella canis in male dogs

In male dogs, Brucella canis frequently causes epididymitis, ultimately resulting in testicular atrophy and infertility. Although B. canis predominantly affects the epididymis, the misleading term “orchitis” is still commonly used by clinicians. Of additional concern, diagnosis in dogs remains challenging because of variable sensitivity and specificity of serologic assays and fluctuations in bacteremia levels in infected dogs, reducing the sensitivity of blood culture. We describe here the histologic lesions in the scrotal contents of 8 dogs suspected of being infected with B. canis and clinically diagnosed with orchitis. We explored the possibility of using immunohistochemistry (IHC) and real-time PCR (rtPCR) in formalin-fixed, paraffin-embedded (FFPE) tissues to detect the presence of B. canis. Epididymitis of variable chronicity was identified in all 8 dogs, with only 3 also exhibiting orchitis. Using rtPCR, the presence of B. canis was identified in 4 of 8 dogs, with 3 of these 4 dogs also positive by IHC. These results suggest that rtPCR and IHC are promising techniques that can be used in FFPE tissues to detect B. canis when other detection techniques are unavailable. Additionally, accurate recognition of epididymitis rather than orchitis in suspect cases could aid in accurate diagnosis.     

ULTRASONOGRAPHIC APPEARANCE AND ETIOLOGY OF CORRUGATED SMALL INTESTINE

An ultrasound pattern of corrugated, and sometimes thickened, bowel wall has been associated with pancreatitis and small intestinal lymphangiectasia. In a retrospective study, records of dogs and cats with an ultrasound diagnosis of corrugated bowel were examined for age, breed, gender, presenting complaint, abdominal radiographic results, and final diagnosis. Eighteen dogs and six cats had an ultrasound diagnosis of corrugated bowel. The final diagnosis was pancreatitis (12 of 24), peritonitis (4 of 24), enteritis (2 of 24), pancreatic neoplasia (2 of 24), diffuse abdominal neoplasia (1 of 24), lymphocytic-plasmacytic enteritis (1 of 24), thrombosis/infarction (1 of 24), and protein-losing enteropathy and acute renal failure (1 of 24). The presence of bowel wall corrugation, although a nonspecific finding, should alert one-to the possibility of pancreatitis, enteritis, peritonitis, neoplasia, or bowel wall ischemia.