Tests for the depolymerization of polyacrylamides as a potential source of acrylamide in heated foods

This study was conducted to test the possibility that polyacrylamides used in agriculture may contribute to acrylamide formation in heated foods by thermal depolymerization. Two samples of polyacrylamide with low molecular weights of 1.5 and 10 kDa were used to test for in-chain and end-chain depolymerization. They were added as aqueous solutions to filter paper for heating in a drying/dry environment and added to a cooking oil for heating in a fatty environment. The heating conditions were 175 degrees C for 15 and 30 min, respectively. Both regimens were tested in the absence and presence of the redox-active metal ions Fe(III) and Cu(II), and all tests were conducted without the exclusion of atmospheric oxygen. There was no evidence of any significant depolymerization of polyacrylamide to free acrylamide monomer, <0.04%. In fact, residual levels of acrylamide present already in the low molecular weight polymers were seen to fall by 50-80% on heating. Consequently, it is concluded that even if polyacrylamides were to contaminate agricultural crops and foods derived therefrom (which itself is an unproven suggestion), there is no evidence that the polymers would depolymerize on heating of the food to form acrylamide in any significant amount.     

Pathological and Bacteriological Studies of Hydrosalpinx in Buffaloes

The objectives of the present study were to investigate the bacteria accompanying hydrosalpinx of the buffalo cow and investigate the correlation between bacterial infection of the uterus and hydrosalpinx. Buffalo cows’ reproductive tracts were collected from Mosul abattoir. A total 385 uterine samples were examined of which 25 were having hydrosalpinx. Swabs for bacteriology, fluid for cytology and biopsies for histopathology were collected from the hydrosalpinx and the uterus from each samples included in this study. Results of this study indicated high prevalence of hydrosalpinx (6.5%) including unilateral (n = 19; 76%) and bilateral (n = 6; 24%) hydrosalpinx. Although 16 samples (64%) of the hydrosalpinx samples had no bacterial growth, the most prevalent bacteria recovered from hydrosalpinx were Corynebacterium hemolyticum and Actinomyces bovis, 42.8% and 28.6%, respectively. The most prevalent bacteria in the uterus were Archanobacterium pyogenes (18.5%), Staphylococcus aureus (14.8%), and Listeria monocytogenes (11.0%). Higher rates of leukocytes infiltration (p < 0.01) were observed in the uterine discharge than hydrosalpinx. A significant (p < 0.01) increase in lymphocytes was found in uterine discharge. Microscopic examination of the hydrosalpinx showed mucosal atrophy and dilatation of oviductal lumen without any signs of inflammation. It could be concluded that there is no correlation between bacteria isolated from uterus and hydrosalpinx. No association was found between bacteriological cultures and hydrosalpinx. Inflammation of the uterine tissue could be extended to utero‐tubal junction producing local inflammation resulting in fibrosis and tubal obstruction. The obstruction in the lumen of the oviducts resulted in accumulation of fluid.     

The effect of a staphylococcal cell wall factor on the early inflammatory response to staphylococcal infection of the lactating bovine udder

The effect on the early inflammatory response in the bovine mammary gland of a factor extracted from the cell wall of Staphylococcus aureus was studied. The insoluble factor was extracted from a 3h-culture, and was mixed with S. aureus from an overnight culture (OF) for experimental infection of a lactating quarter. Other quarters were infected with a 3h or an overnight culture (O). Five cows were used in the experiment. The O-quarters showed more severe clinical signs than seen in the 3h-and OF-quarters. Antitrypsin levels and NAGase concentrations were much reduced in the 3h-and OF-quarters. While the cell wall factor profoundly reduced the early inflammatory response, the effect on the final outcome of the infection was not determined.     

A survey of cattle producers in the Boophilus microplus endemic area of Queensland to determine attitudes to the control of and vaccination against tick fever

SUMMARY: A survey by mail was used to determine the views of beef producers in the Boophilus microplus endemic area of Queensland on the control of and vaccination against tick fever. Data from 448 questionnaires were analysed, representing 2.7% of beef producers in the survey area. Producers considered buffalo fly ( Haematobia irritans exigua ) infestation as the most important problem whereas tick fever ranked sixth overall. Private veterinarians were regarded as the most important source of information on vaccines for cattle followed by a weekly rural newspaper. From the survey we estimate that about 33% of producers used the tick fever vaccine produced by the Tick Fever Research Centre of Queensland Department of Primary Industries but there were significant (P < 0.05) variations between regions and herds. Large herds (≥ 400 head) in south-east Queensland were the most likely to be vaccinated against tick fever. Of the producers who did not use the vaccine, over 70% replied that there was no need to vaccinate because of the low risk of the disease in their herds. In 52% of unvaccinated herds the treatment of animals with acaricide was considered the most important means of tick fever control and 61% of these herds comprised Bos indicus x Bos taurus or Bos indicus cattle.     

一例犬细小病毒病的诊断与治疗

犬细小病毒病是由犬细小病毒引起的以出血性肠炎或非化脓性心肌炎为主要特征的一类疾病.根据发病情况、临床特征、剖检变化、实验室诊断等情况,对一例犬细小病毒病临床病例进行了诊断并采取了相应的治疗措施,取得了较好的效果.