Application of proton-transfer-reaction mass spectrometry to the assessment of odorant removal in a biological air cleaner for pig production

There is an urgent need to develop odor reduction technologies for animal production facilities, and this requires a reliable measurement technique for estimating the removal of odorants. The purpose of the present experiment was to investigate the application of proton-transfer-reaction mass spectrometry (PTR-MS) for continuous measurements at a biofilter from SKOV A/S installed at a pig production facility. PTR-MS was able to handle the harsh conditions with high humidity and dust load in a biofilter and provide reliable data for the removal of odorants, including the highly odorous sulfur compounds. The biofilter removed 80-99% of carboxylic acids, aldehydes, ketones, phenols, and indoles and ca. 75% of hydrogen sulfide. However, only ~0-15% of methanethiol and dimethyl sulfide was removed. In conclusion, PTR-MS is a promising tool that can be used to improve the development of biological air cleaning and other odor reduction technologies toward significant odorants.     

Proteolytic activity in byproducts from cod species caught at three different fishing grounds

Proteolytic activity in byproducts from cod species caught at three different fishing grounds has been characterized and compared. The overall highest activity in the byproduct fractions was found in viscera at pH 3 (35 degrees C). Cut off and liver fractions also show maximum activity at pH 3, 35 and 50 degrees C, respectively. Proteolytic activity in viscera and cut off fractions are more affected by fishing ground than by species. Proteolytic activity at pH 3 in viscera is higher in samples from the south coast of Ireland, while viscera samples from the Icelandic Sea have the highest activity at pH 7. For cut off, the activity is higher in samples from the south coast of Ireland than the other two fishing grounds.     

Seasonal aspects of sciarid emergence in arable land (Diptera: Sciaridae)

In April-October 1990-95 soil sciarids emerging in two Danish barley fields were recorded by means of emergence traps. In 1990-92 the fields were conventionally tilled, in the autumn of 1992 one of the fields was abandoned as annual set-aside (1993) and in 1994-95 most of the field was recropped. In the cropped and uncropped fields 480-527 ind. m⁻² and 369-433 ind. m⁻² emerged, respectively. Ten sciarid species were recorded, eight of which are well-known farmland inhabitants. Apparently, abandonment affected Scatopsciara atomaria negatively, whereas Corynoptera perpusilla was encouraged. The predominant species were probably bivoltine or trivoltine. In Lycoriella castanescens, Scatopsciara atomaria, Corynoptera perpusilla and Bradysia trivittata the female proportion increased significantly during the season. It is assumed that the primary sex ratio of the species is spanandrous. The seasonal change in sex ratio might arise from the unusual modes of reproduction demonstrated in Sciaridae. In Lycoriella castanescens, Bradysia trivittata and Corynoptera perpusilla a significant seasonal increase in wing length was recorded, whereas the wing length of Scatopsciara atomaria and Bradysia rufescens decreased significantly during the season. This suggests a seasonality in the production of large, potentially migrant females. In arable fields sciarid life history traits such as sex ratio, adult biometry and fecundity might be facultative.     

Effect of Fish Silage on Yield and Chemical Composition of Italian Ryegrass (Lolium multiflorum Lam.)

Seed production of spinach (Spinacea oleracea L.) is positively affected by increasing the amounts of nitrogen (N); however, regulations restrict the application rate of N in Danish agriculture. The aim of our study was to test different N application strategies in spinach seed production and their effects on N concentration, seed yield, seed weight and germination. A total amount of 100–150 kg N ha^?1 was broadcast or placed at sowing or applied as a split application at sowing and pre-elongation at the Danish Institute of Agricultural Sciences, location Flakkebjerg. Seed yields were positively affected by the high N applications, but no difference was observed between 150 kg N ha^?1 broadcast at sowing, and 40 kg N ha^?1 broadcast at sowing with an additional late application at a rate based on soil mineral N analysis. No consistent pattern was observed between N management strategy and seed weight or N management strategy and germination. A high N concentration in the plants at the start of growth showed negative effects on final seed yield, whereas later in the season there was a significantly positive correlation between N concentration in the plants and seed yield. A soil mineral analysis can be used as a tool to adjust the N application rate when a split application strategy is chosen.     

Hatchery Production of Scallop Larvae (Pecten maximus) – Survival in Different Rearing Systems

Scallop farms in Norway rely exclusively on hatchery production of spat. Larval rearing is one of the most difficult parts of the production, and several experiments have been performed during the last years to improve the larval systems. This paper describes results from commercial and experimental trials obtained between 1996 and 2001. Four different rearing systems were compared: untreated batch cultures, chloramphenicol-treated batch cultures, flow-through cultures with filtered water and flow-through cultures with water from a biofilter. The chloramphenicol-treated batch cultures had overall significantly higher survival rates than the untreated and flow-through cultures. There were no significant differences in survival between untreated and flow-through cultures. The average survival rates for the untreated, treated and flow-through cultures were 6.8, 23.0 and 8.6%, respectively. No significant seasonal differences were found for the untreated and treated larval groups, whereas for larvae reared in flow-through systems survival was significantly higher in the winter than the spring. Overall best results were obtained during winter in years with high salinity water in the fjord.     

Prevalence of Cryptosporidium parvum infection in southwestern Ontario and its association with diarrhea in neonatal dairy calves

Cryptosporidium parvum infection was detected in 203 (40.6%) of 500 Ontario dairy calves aged 7 to 21 d, on a convenience sample of 51 farms with a history of calf diarrhea. Within-farm prevalence ranged from 0% to 70%, and both shedding and intensity of shedding were significantly associated with diarrhea. This parasite appears to be common in Ontario dairy calves and important as a cause of dairy calf scours in the province.     

A mycobacterial coinfection in a dog suspected on blood smear

A 4‐year‐old neutered female crossbred Shepherd was referred for a history of 10 days of anorexia, polyuria, polydipsia, polyadenomegaly, and diarrhea. On physical examination, the dog appeared quiet, responsive, and apyretic, with generalized and severe lymphadenomegaly. Hematologic abnormalities included neutrophilic leukocytosis with left shift, and lymphopenia. Blood smears revealed intracytoplasmic bacilli negatively stained with May–Grünwald–Giemsa in neutrophils and monocytes. Lymph node smears revealed pyogranulomatous adenitis with calcified deposits and many negative‐staining rod structures, both within the cytoplasm of neutrophils and macrophages, and free in the background. An acid‐fast stain (Ziehl–Neelsen) confirmed the diagnosis of mycobacterial infection. The dog was euthanized for public health and ethical reasons, and the postmortem examination revealed severe and generalized granulomatous and necrotizing lymphadenitis, panniculitis, and hepatitis, and infiltration of epithelioid macrophages in the lungs, colon, and spleen. Numerous acid‐fast bacilli, consistent with mycobacterial infection, were observed both in the cytoplasm of epithelioid macrophages and giant cells, and free in the background. Mycobacterium bovis was first confirmed by conventional PCR of organ extracts. Mycobacterium avium was detected in a culture of the same organs. Further PCR amplifications and sequencing revealed a coinfection with 2 different species of mycobacterium, one belonging to the Mycobacterium avium complex and the other to the Mycobacterium tuberculosis complex.     

Genotype by environment interactions and combining ability for strawberry families grown in diverse environments

Ten seedlings from 36 crosses representing eastern and western North American short day and remontant genotypes were evaluated in 2011 and 2012 in California, Michigan, New Hampshire and Oregon, for phenology, flower related traits, plant characteristics, fruit characteristics and fruit chemistry traits. There was significant variability among genotypes, locations and evaluation year for most of the characteristics; however, few genotype × location and genotype × year interactions were detected. General combining ability variance components were significant for all traits and greater than SCA variance components for peduncle length, total flowering weeks, flowering cycles, truss size, growing degree days for harvest data, remontancy, achene position, ease of capping, fruit weight, percent soluble solids, titratable acidity and soluble solids/titratable acidity. ‘Sarian’ was identified as the best contributing parent for remontancy. Narrow-sense heritability estimates were moderate to high (0.33–0.78) for total flowering weeks, flowering cycle, truss size, remontancy, number of runners, fruit weight, pH, and titratable acidity. Having a better understanding of these attributes will provide breeders guidance on the most effective breeding strategies for incorporating superior traits from this germplasm into their programs.