Volatile components of the anal gland secretion of the striped polecat Ictonyx striatus

The volatile components of the anal gland secretion of an adult, male, Ictonyx striatus were separated and identified by dynamic solvent effect sampling, capillary gas-liquid chromatography, and mass spectrometry. The major component was 2-ethylthiacyclobutane. Nine other sulphur compounds, a ketone, and a hydrocarbon were also identified. Some of these occur in the anal gland secretions of other mustelids

Aggregation pheromones of the bont tick Amblyomma hebraeum : identification of candidates for bioassay

Volatiles emitted by male Amblyomma hebraeum while feeding on a rabbit were quantitatively sampled by the dynamic solvent effect and analysed by capillary gas-liquid chromatography and mass spectrometry. Changes in emissions of 2-methyl propanoic acid, benzaldehyde and 2-nitrophenol paralleled reported increases in the attractiveness of males to conspecific ticks after 4-5 days of feeding. These compounds are therefore candidates for the bioassay of pheromonal activity.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.lmchunu2014mn201

A gas-chromatographic headspace method for the determination of acetone in bovine milk, blood and urine

An automated headspace gas-chromatographic method has been developed for the determination of acetone in the milk, blood and urine of dairy cows. Five ml samples were saturated with 2g of sodium chloride and equilibrated for 30 min at 90°C in a Hewlett-Packard HP 19395A automatic headspace sampler. The headspace volatiles were transferred without splitting to a 25m x 0,3mm x 0,4µm Carbowax column in a Shimadzu GC 9A gas chromatograph, operating isothermally at 50°C. The coefficients of variation for the determination of acetone were 1,5-4,4% for urine, 10,0-24,9% for milk and 2,0-19,6% for blood. The detection limits were 0,0055mg/100ml for milk, 0,0072mg/100ml for blood and 0,0080mg/100ml for urine. The analysis time of 5min per sample provided an adequate rate of throughput for routine monitoring.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Cyclic fluctuations in acetone concentrations in the blood and milk of clinically healthy dairy cows

Milk samples were taken daily or twice weekly, and blood samples twice weekly, from six clinically healthy dairy cows. Acetone concentration was determined by a new headspace gas-chromatographic method that proved to be suitable in terms of practicality, sensitivity and precision. The concentration of acetone in milk was closely correlated with that in blood (r² = 0,967). There was no relationship between lacteal acetone concentration and either somatic cell count or bacterial infection. In both blood and milk there were fluctuations in acetone concentration that were synchronous between the six cows. The fluctuations were apparently cyclic, with a period of approximately 10 d. Such fluctuations have not previously been reported.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Aspects of the ecology of feral cats on Dassen Island, South Africa

Numbers of feral cats on Dassen Island (33°25'S/18°06'E) increased from 20–25 in May 1979 to 37–50 in June 1980. Kittens were born in eight months of the year with birth peaks in October-November and in January. Mean litter size was 2,7 and 80% of kittens born between August 1979 and January 1980 survived until June 1980. Kittens died from starvation and disease. In June 1980 51–56% of the cats were <1 year old. The number of cats is recovering rapidly from heavy culling. Depredation by cats is a potential threat to sea-bird colonies. The diet and feeding behaviour of the cats were studied in order to assess the importance of this threat. An ‘average’ cat's annual diet, assessed from scats, included: 134 European rabbits (Oryctolagus cuniculus), 37 jackass penguins (Spheniscus demersus), 25 Cape cormorants (Phalacrocorax capensis), 31 other birds and 24 house mice (Mus musculus). Each cat killed 105 rabbits and 13 birds each year, the balance of its diet being made up by carrion. Adverse effects of the presence of cats, compared to other factors, were not yet so serious as to necessitate artificial control of cat numbers

Possible use of shamming by a brown hyaena in an aggressive encounter with a pride of lions

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Volatile components from the anal glands of the Yellow Mongoose Cynictis penicillata

Twenty-two components of the odour of the anal-gland secretions of a male and a female yellow mongoose Cynictis penicillata were identified by dynamic solvent effect sampling, gas-liquid chromatography and mass spectrometry. The odour volatiles were considerably more diverse than those reported from the anal gland secretions of Herpestes auropunctatus and H. ichneumon