Leptospira interrogans serovar hardjo is not a major cause of bovine abortion in Victoria

The aim of this study was to determine whether evidence could be obtained of foetal infection with Leptospira interrogans serovar hardjo in aborted foetuses collected from dairy farms. Material from 197 abortions occurring over a wide area of Victoria was collected over 3 years. None of 195 foetal kidney cultures or 7 cultures from membranes was positive for leptospiral organisms. Immunogold silver staining for leptospires was performed on sections of kidneys, lungs or heart from 156 foetuses, with negative results. Evidence of transient leptospiral infection in 11 of 123 foetuses was obtained by foetal heart blood serology. Two isolates of L. interrogans serovar hardjo were obtained from the urine of milking cows. These strains were examined by restriction endonuclease analysis and both were shown to be of the genotype Hardjobovis, as have been all Australian isolates studied so far. It appears that foetal infection with serovar hardjo is not associated with any substantial proportion of bovine abortions in Victoria, in contrast to the situation in Northern Ireland. The apparent absence from Victoria of the pathogenic genotype Hardjoprajitno is a possible explanation.     

Isolation of Mycoplasma synoviae from infectious synovitis of chickens

This report describes the first isolations of Mycoplasma synoviae from the synovial sheaths and joints of commercial chickens affected with synovitis in Australia. Over 4 years 3 separate outbreaks were investigated in which up to 20% of birds exhibited clinical signs of poor growth and "hot foot" syndrome (swollen inflamed footpads). Once an outbreak occurred, chronic infection of the farm usually ensued. Grossly the hocks and footpads were swollen by a purulent exudate and associated inflammatory changes with histological features of a severe acute synovitis. Seroconversion of the flocks occurred at the time of the development of lesions. M. synoviae specific antibodies were demonstrated by ELISA in the joint fluid of affected birds. It is concluded that the cases described are similar to avian infectious synovitis syndrome caused by M. synoviae previously described overseas.     

Paraneoplastic pemphigus in a dog with splenic sarcoma

Paraneoplastic pemphigus (PNP) is an autoimmune blistering skin disease of humans that consists of characteristic skin lesions associated with concurrent neoplasia. In this study we provide histologic and serologic evidence to support a diagnosis of PNP in a dog with splenic sarcoma. Skin lesions consisted of widespread erosions involving haired skin, mucocutaneous junctions, and oral mucosa. Microscopic examination of skin and mucosae revealed lesions consistent with both pemphigus vulgaris and erythema multiforme. Immunoprecipitation confirmed that circulating IgG autoantibodies from this patient recognized five distinct antigens, presumed to represent epidermal plakins. Clinical, histopathologic, and immunologic findings in this patient were similar to those observed in human patients with PNP. The splenic neoplasia in this dog was diagnosed as a phenotypically variable spindle cell sarcoma. To date, only one other dog has been reported with PNP. This is the second reported case of canine PNP and the first patient in whom skin lesions were identified in association with splenic neoplasia.     

Correlation between pregnancy diagnosis by membrane slip and embryonic mortality.

In a study involving 7,477 pregnant cows (5,426 Holstein-Friesians and 2,051 Guernseys), each pregnancy was diagnosed by rectal palpation, using the membrane slip technique. Each cow was examined twice, first by a veterinary student, then by a clinician. Of the cows diagnosed pregnant, 7,058 (94.4%) calved. The embryonic death rate in cows examined during the first 50 days of gestation was significantly (P less than 0.001) greater than that associated with examinations after 50 days of gestation. A significant difference was found between herds in different years (P less than 0.05). There was no conclusive indication that embryonic loss at the time of or shortly after early examination was iatrogenic abortion resulting from the membrane slip technique.     

Measurement of acrylamide and its precursors in potato, wheat, and rye model systems

The relationship between acrylamide and its precursors, namely, free asparagine and reducing sugars, was studied in cakes made from potato flake, wholemeal wheat, and wholemeal rye, cooked at 180 degrees C, from 5 to 60 min. Between 5 and 20 min, major losses of asparagine, water, and total reducing sugars were accompanied by large increases in acrylamide, which maximized in all three products between 25 and 30 min, followed by a slow linear reduction. Acrylamide formation did not occur to a large degree until the moisture contents of the cakes fell below 5%. Linear relationships were observed for acrylamide formation with the residual levels of asparagine and reducing sugars for all three food materials.     

Formation of 2-alkyl-(2H)-thiapyrans and 2-alkylthiophenes in cooked beef and lamb

2-Alkyl-(2H)-thiapyrans and 2-alkylthiophenes have been identified in the volatiles of cooked beef and lamb. The quantities of both groups of compounds were higher in the meat of animals fed lipid supplements high in n-3 polyunsaturated fatty acids. 2-Alkyl-(2H)-thiapyrans were formed when (E,E)-2,4-dienals (C(6)-C(11)) and hydrogen sulfide were heated at 140 degrees C for 30 min. This confirmed their proposed route of formation in cooked meat from lipid-derived aldehydes and hydrogen sulfide; the latter was produced from the degradation of cysteine, via the Maillard reaction. The mass spectra and NMR spectra of these thiapyrans are reported for the first time. Although 2-alkyl-(2H)-thiapyrans were found to have only low odor potency, the reactions by which they are formed may have important implications for meat flavor. These reactions may remove potent aroma compounds and their intermediates from meat, thus modifying the overall aroma profile.