Attraction and antennal response of the common wasp,Vespula vulgaris (L.), to selected synthetic chemicals in New Zealand beech forests

BACKGROUND: The common wasp, Vespula vulgaris (L.), and the German wasp, Vespula germanica (F.), are significant problems in New Zealand beech forests (Nothofagus spp.), adversely affecting native birds and invertebrate biodiversity. This work was undertaken to develop synthetic attractants for these species to enable more efficient monitoring and management. RESULTS: Seven known wasp attractants (acetic acid, butyl butyrate, isobutanol, heptyl butyrate, octyl butyrate and 2,4‐hexadienyl butyrate) were field tested, and only heptyl butyrate and octyl butyrate attracted significantly higher numbers of wasps than a non‐baited trap. Accordingly, a series of straight‐chain esters from methyl to decyl butyrate were prepared and field tested for attraction of social wasps. Peak biological activity occurred with hexyl butyrate, heptyl butyrate, octyl butyrate and nonyl butyrate. Polyethylene bags emitting approximately 18.4–22.6 mg day^?1 of heptyl butyrate were more attractive than polyethylene bags emitting approximately 14.7–16.8 mg day^?1 of heptyl butyrate in the field. Electroantennogram (EAG) studies indicated that queens and workers of V. vulgaris had olfactory receptor neurons responding to various aliphatic butyrates. CONCLUSION: These results are the first to be reported on the EAG response and the attraction of social wasps to synthetic chemicals in New Zealand beech forests and will enable monitoring of social wasp activity in beech forests. Copyright © 2009 Society of Chemical Industry     

Population sizes and frequency of Malassezia pachydermatis at skin and mucosal sites on healthy dogs

Skin and mucosal carriage of Malassezia pachydermatis was studied in 20 healthy pet dogs of various breeds and in 20 kennelled beagles. Using swabs, anal carriage was detected in 10 pet dogs and 11 beagles and the nose, mouth, prepuce and vulva were shown to be infrequently colonised. M pachydermatis was isolated from the external ear canal of 11 beagles and two pet dogs; both the population sizes and frequency of isolation were significantly (P<0·05) greater in the beagles. The yeast was infrequently isolated from the axilla and groin in low numbers using contact plates and detergent scrub samples but was often cultured from the lower lip and the dorsal interdigital spaces; isolation frequencies and population sizes in the two groups of dogs were not significantly different. These results demonstrate that the anus, external ear canal and lip and interdigital skin of healthy dogs are frequently colonised by M pachydermatis.     

Clostridial myocarditis in lambs

Five outbreaks of myocarditis were investigated in young sheep. They occurred during late winter and spring when there was lush growth of pasture following a prolonged period of drought. Clinically the disease was characterised by sudden death and pathological findings were dominated by acute multifocal locally extensive necrotising and haemorrhagic myocarditis. A fluorescent antibody technique was used to demonstrate the presence of Clostridium chauvoei in paraffin embedded sections of myocardium from 4 of the outbreaks.     

Bovine viral diarrhea in a newborn calf

Bovine viral diarrhea virus was believed to be the cause of ill-thrift since birth, resulting in death of a Holstein calf. Bovine viral diarrhea virus was isolated from Peyer's patches and mesenteric lymph nodes, but serum neutralizing antibodies were not detected. The lymphoid depletion and myeloid suppression seen in this case may be a factor in the immune system dysfunction described for bovine viral diarrhea. Typical ulcerative lesions within the alimentary tract were not observed.     

Keratomas in horses: seven cases (1975-1986)

The diagnosis of keratoma in 7 horses and their treatment and outcome were evaluated. Horses were 2 to 20 years old, of various breeds, and were intact or castrated males. All were lame, and 6 horses had had previous injuries of the affected hoof that had not responded to prior treatments. Only 1 hoof was affected in each horse. Keratomas were beneath the hoof wall (6 horses) or sole (1 horse). Radiographically, a circular or semicircular defect with a discrete margin was present in the distal portion of the third phalanx in 3 horses. Grossly, keratomas were firm solitary masses (1.5 to 5 cm diameter); gray, tan, or yellow; and oval or conical. Keratomas were excised from beneath the hoof wall by removing a section of hoof wall (5 horses) or by undermining the wall beginning at its junction with the sole (1 horse). A keratoma beneath the sole in 1 horse was excised by excavating the sole to the level of the palmar surface of the third phalanx. Keratoma was verified microscopically by the presence of characteristic rings of squamous epithelial cells with abundant keratin. Purulent exudate and inflammatory infiltrate often were present concurrently, reflecting an associated localized infection. Aftercare included daily application of an antiseptic iodine solution and foot bandages, and shoeing with a treatment plate several weeks after surgery. Hoof and sole defects healed completely between 6 months and 1 year. By 1 year after surgery, 6 horses were sound, and keratoma had not recurred.     

Canine congenital portosystemic encephalopathy

The case records of 21 dogs with congenital portosystemic encephalopathy are reviewed. The disorder was most common in Australian cattledogs (blue heelers; 8 cases), Old English sheepdogs (3 cases) and Maltese terriers (3 cases). Extra-hepatic shunts occurred in small breeds, with the exception of 1 cattledog, while intra-hepatic shunts occurred in the medium to large breeds. The most common clinical pathology abnormalities were abnormal ammonia tolerance, mild to moderate increases in plasma alanine aminotransferase or alkaline phosphatase concentrations, decreased total serum protein concentrations, increased fasting ammonia concentrations and ammonium biurate crystalluria. Radiological examination revealed that all the dogs had a small liver. The kidneys were enlarged in 5 of 10 dogs in which kidney size could be estimated. Surgical ligation of an extra-hepatic shunt was successful in 2 of 4 dogs in which it was attempted. Medical management resulted in alleviation of clinical signs in 5 of 8 dogs. The period of successful treatment ranged from a few months to over a year.     

Effects of Temperature on the Uptake and Depuration of 2-Methylisoborneol (MIB) in Channel Catfish Ictalurus punctatus

The microbial metabolite 2-methylisoborneol (MIB) imparts a muddy off-flavor to channel catfish Ictalurus punctatus . Uptake and depuration of MIB from fish are important considerations in the design and implementation of systems to remove off-flavors from fish prior to processing. The kinetics of MIB uptake by channel catfish were determined by placing fish in 6.5, 14.0, 25.0, and 34.0 C water containing approximately 1.0 μg/L chemically-synthesized MIB. Fish were sacrificed following 0, 2, 4, 8, and 24 h exposure to MIB. Fillet tissue samples were subjected to gas chromatographic and fat content analysis. The model for MIB uptake was:
MIB in fillet tissue (μg/kg) =−0.61 ± 4.2 [log( h ± 1)] ± 0.0076( T ) ( h ) ± 0.089( T ),
where h is the duration of exposure to MIB in hours and T is the water temperature in degrees C. The model accounted for 74% of the total variation observed in the tissue MIB concentrations and indicated that the fillet fat content was not strongly correlated with MIB uptake. To investigate the depuration of off-flavors, exposure to MIB was halted. Tissue samples were obtained 4, 8, 24, 48, and 72 h from fish held at 6.5, 14.0, 25.0, and 34.0 C. These data yielded the model:
MIB in fillet tissue (μg/kg) = 3.6 ± 0.176( T ) – 2.06 [log( h ± 1)] – 0.00296( T ) ( h ) ± 0.197 (% fat),
where h is the duration of exposure to MIB in hours, T is the water temperature in degrees C, and % fat is the % fat in the fillet tissue. The model accounted for 67% of the total observed variation in tissue MIB concentrations. Reducing the fat content of fish and optimizing water temperatures may augment MIB removal from fish tissues prior to processing.     

Double blind, placebo-controlled, crossover study of evening primrose oil in the treatment of canine atopy.

Thirty-five dogs with non-seasonal atopic dermatitis were used in a double-blind, placebo-controlled crossover study of the effects of evening primrose (Oenothera biennis) oil. There was a significant treatment effect (P less than 0.05) on erythema. An analysis of the changes in plasma phospholipid levels of essential fatty acids revealed a significant (P less than 0.05) rise in linoleic acid concentration above that in the placebo group. Arachidonic acid levels in the treated group increased significantly (P less than 0.005) in the first phase and also in the second phase (P less than 0.05). In the second phase the levels of arachidonic acid in the active and placebo groups differed significantly (P less than 0.05) and there was a significant treatment effect (P less than 0.05).