Failure to protect goats following vaccination with soluble proteins of Sarcoptes scabiei: evidence for a role for IgE antibody in protection

Developing an anti-scabies vaccine is thought to be a feasible alternative to chemical control, since animals which have recovered from sarcoptic mange become resistant against mite reinfestation. The purpose of this study was to evaluate the protective value of immune responses developed in animals after immunisation with soluble mite proteins. Soluble proteins from Sarcoptes scabiei were extracted then subjected to ion exchange chromatography, and proteins from the column were eluted step-wise with 0%, 10%, 25% and 50% of 1 M solution of NaCl in a Tris buffer. Each protein fraction was concentrated and dialysed against PBS. To evaluate the immunogenicity of the fractions, 36 goats were allocated into six groups, group1 goats were unvaccinated, group 2 were vaccinated with intact soluble mite proteins, and groups 3-6 were vaccinated respectively with the fractionated proteins. Vaccinations were conducted four times with 1 mg protein/dose and 4-week intervals between vaccinations. One week after the last vaccination, all goats were challenged with approximately 2000 live mites on the auricles and infestations were allowed to progress for 6 weeks. The severity of lesions caused by the infestation was assessed throughout the study. The challenge caused mange or encrustation dermatitis in all animals and no differences in severity of lesions were observed between vaccinated and unvaccinated control goats. Vaccination with each fraction of the mite proteins invoked high levels of scabies-specific IgG in the serum of all animals but failed to induce specific IgE as determined by Elisa. In contrast, goats challenged experimentally with a primary or repeated mite challenge developed strong serum IgE and IgG antibody responses to Sarcoptes antigens. The latter animals were shown in a previous study to be resistant to reinfestation. The lack of immune protection in the vaccinated animals may be attributed to the absence of protective levels of IgE antibody, and the present findings indicate that allergens and IgE antibody is important in immunity to S. scabiei infection.     

Effect of vacuum treatment on smoke penetration into boiled skipjack loins for production of smoke-dried skipjack

ABSTRACT: The present work evaluates the effect of vacuum treatment on smoke penetration into boiled skipjack loins for the production of smoke-dried skipjack. Using a vacuum freeze-dryer, the boiled skipjack loins were vacuumed immediately after being boiled at a pressure of 400 Pa for 30 min in order to reduce the lipid and water contents. The vacuumed boiled meats were then smoked and dried at 90 ± 10°C for 3 h a day for 6 days in a metal kiln (internal diameter 24 cm × 24 cm × 70 cm height), using an electric heater (1.2 kW) to heat and generate smoke from cherry tree wood chips. Also, non-vacuumed boiled meats were smoked in the same manner as a control. The vacuum treatment reduced the lipid and water contents by as much as 0.6% and 2.7% on the wet weight basis, respectively. Histological observations showed many clearances among the muscle fibers of the vacuumed boiled meats. The content of phenols that had penetrated the vacuumed boiled meats during the smoke drying procedure was significantly larger ( P < 0.05) than that of the non-vacuumed boiled meats. Accordingly, the vacuum treatment accelerated the penetration of phenols into the boiled meats and enhanced the function of antioxidant substances, which improved the quality of the smoke-dried skipjack.     

Clinical report of a paralytic syndrome affecting stallions, mares and foals on a thoroughbred studfarm

An outbreak of ataxia and paralysis on a Thoroughbred studfarm is reported. The cause of the disease was attributed to equid herpesvirus (EHV1) infection which stemmed from a single 10-month abortion on the studfarm. Stallions, mares and foals were all affected but the most serious clinical signs occurred in the mares. there were 35 out of 39 mares, 2 out of 4 stallions and 5 out of 39 foals which exhibited signs of ataxia. Nine mares became recumbent and died or were euthanased. Treatment with betamethasone and antibiotics was given. The outbreak was contained to one area of the stud apart from secondary spread to 2 in-contact mares on different premises.     

‘Chambourcin’ grapevine (Vitis vinifera Vitis L.) berries display sustained post-veraison accumulation of oxalic acid

SUMMARY

A substantial accumulation of organic acids (OAs) occurs during pre-veraison grape berry development, which results in low pH conditions and contributes to the organoleptic properties of the fruit. The main OAs in most grape berries are tartaric acid (TA) and malic acid (MA). MA is accumulated via a primary metabolic shunt, whereas TA is accumulated via ascorbic acid (AA; vitamin C) metabolism. Oxalic acid (OX) is also derived from AA in competition with TA, and results from a cleavage between the second and third carbon atoms. Oxalic acid is subsequently biomineralised as calcium oxalate crystals in idioblast cells. We have examined the biosynthesis of TA, MA, and OX during grape berry development in four grapevine cultivars. We show that in the Vitis vinifera L. Vitis L. complex inter-specific hybrid, ‘Chambourcin’, there is a high capacity to accumulate OX during post-veraison fruit development. OX content increased from approx. 1 mg g^–1 to 3 mg g^–1 berry fresh weight between 14 and 16 weeks post-anthesis, resulting in OX levels that were similar to the MA levels in mature fruit. Whether OX accumulation occurs due to increased biomineralisation or biosynthesis, our results show that ‘Chambourcin’ grape berries represent the only documented case of post-veraison accumulation of OX.     

Quality improvement by vacuum treatment of boiled skipjack loins for the production of dried skipjack

ABSTRACT: This study attempted to reduce the lipid and water contents in boiled skipjack loins by vacuum treatment and the quality of vacuumed boiled meat was then evaluated during the chilled and frozen storage. The boiled meats were vacuumed at a pressure of 400 Pa for 30 min using a vacuum freeze dryer as an experimental convenience in order to degrease, cool and dehydrate rapidly. The vacuumed boiled meats were stored at 0.0 ± 0.2°C for 10 days and at −20 ± 0.5°C for 90 days. The unvacuumed boiled meats were cooled by air-cooling and stored as the control. Lipid content on a wet basis (w.b.) was reduced as much as 0.5% in the ventral part and 0.4% in the dorsal part of the boiled meats after vacuum treatment. Water content (w.b.) was reduced as much as 2.5% in the ventral part and 3.0% in the dorsal part. The thiobarbituric acid and volatile basic nitrogen values in vacuumed boiled meats were significantly lower ( P < 0.05) than that in unvacuumed boiled meats during storage. Inosine monophosphate (IMP) was only detected as a major nucleotide (about 70%) in boiled meats, and the decomposition of IMP in vacuumed boiled meats was smaller than that in unvacuumed boiled meats during storage. It was concluded that the quality of boiled skipjack loins could be improved by vacuum treatment as a preprocessing procedure in the production of dried skipjack such as katsuobushi .