Fowl adenovirus: history, emergence, biology and development of a vaccine against hydropericardium syndrome

The poultry industry has emerged as one of the largest and fastest growing public sectors in the developed and developing countries. Unfortunately, this industry is under a major threat from diseases that are viral (Newcastle disease, infectious bursal disease, influenza, hydropericardium syndrome), bacterial (colibacillosis, pasteurellosis, salmonellosis, mycoplasmosis), parasitic (coccidiosis, histoplasmosis) or nutritional (dyschondroplasia, osteoporosis). Among these diseases, hydropericardium syndrome (HPS) is one of the important emerging diseases occurring in the specific areas of the world where broilers (chickens) are reared under intensive conditions. HPS was first observed in 1987 at Angara Goth, an area near Karachi, Pakistan, where broilers are raised. Since then, HPS has been reported in many countries of the world. From these reported cases, an adenovirus that was either isolated from or visualized electron microscopically in the liver of affected broilers has been implicated in the syndrome. The syndrome has been reproduced by inoculation of isolated fowl adenovirus (FAdV) strains, and hence, the syndrome is also called infectious hydropericardium syndrome. To our knowledge, HPS has not been observed in humans, so it is not considered a zoonotic disease, but it is of economic importance and causes huge losses to the poultry industry. Efforts have been made to develop conventional vaccines against this disease, which were formulated from infected liver homogenate. Formalin-inactivated liver organ vaccines have failed to protect the poultry industry. Hence, there is a dire need to develop a suitable vaccine to combat this disease. Currently, recombinant vaccine candidates are being developed by using molecular biology and biotechnological approaches for the prevention and control of infectious diseases, including HPS. Therefore, it is suggested that the immunogenicity of these recombinant proteins should be evaluated for their use as subunit vaccines.

Effect of wheat flour, Bengal gram flour and corn flour on lipid metabolism in rats

Male albino rats were fed on respective diets of wheat flour, Bengal gram flour and corn flour for 8 weeks at the 59% level. It was observed that the increase in weight after wheat flour and Bengal gram flour feeding was 6.8 and 12.0% respectively and that the decrease after corn flour feeding was 5.2% as compared to the control animals on sucrose diet. Serum cholesterol and liver cholesterol levels were significantly (p less than 0.01) decreased after wheat flour, Bengal gram flour and corn flour feeding.

Influence of garlic on serum cholesterol, serum triglycerides, serum total lipids and serum glucose in human subjects

Human subjects were used for a garlic experiment. The subjects were given a fat-rich diet for 7 days and on the 8th day the fasting blood was analyzed for serum cholesterol, serum triglycerides, serum total lipids and serum glucose. The human subjects were then given a fat-rich diet with 40 g of garlic for 7 days and on the 15th day the fasting blood was analyzed for the above investigations. On a fat-rich diet the serum cholesterol, serum triglycerides and serum total lipids were significantly increased as compared to normally fed diet. When 40 g of garlic was substituted in fat-rich diet for 7 days, the garlic significantly reduced the serum cholesterol and serum triglycerides.

Effect of triglycerides on the production of lipids and lipase by Mucor hiemalis

The effect of triglycerides on the growth of Mucor hiemalis and the production of lipase and mycelial lipids was studied. Addition of 1% triglycerides to the fermentation medium was best for the mycelial as well as the broth lipase production. The added triglycerides seemed to be utilized through the formation of free fatty acids, and towards the end of the growth phase most of the triglycerides and their hydrolysis products were utilized. The mycelial lipase activity was maximum (66 U/g dry mycelium) at the end of the growth phase, while the maximal broth lipase activity (204 U/100 mL) was achieved after the cell lysis had started. The lipids produced per gram mycelia were high initially (260 mg/g dry weight at 48 h), reducing gradually later. With increase in growth the maximum mycelial lipids per 100 mL of culture medium was obtained after 96 h (176 mg/100 mL). The various fractions detected in the mycelial lipid extracts were sterol esters, triglycerides, free fatty acids, diglycerides, sterols, monoglycerides, phosphatidyl ethanolamine, phosphatidyl choline, and small amounts of an unknown polar lipid at all the stages of fermentation studied. Proportion between total neutral and total polar lipids remained nearly constant throughout fermentation.

Lipase Induction in Mucor hiemalis

The influence on lipase induction in Mucor hiemalis of different types of triglycerides containing mainly oleic acid (olive oil), erucic acid (mustard oil), or saturated fatty acids of 8 to 16 carbons (coconut oil) was studied. The fungus was grown in shake flasks in a fermentation medium containing peptone, minerals, and glucose or one of the oils as the carbon source. Maximum lipase was produced when the initial pH of the fermentation medium was kept at 4.0. Addition of Ca 2+ to the medium did not increase lipase production. The optimum pH for activity of both the mycelial and extracellular lipases was found to be 7.0. The fungus produced a significant amount of lipase in the presence of glucose, but the lipase activity increased markedly when olive oil was added to the medium at the beginning of the fermentation. Addition of olive oil at a later stage did not induce as much enzyme. Studies with washed mycelia showed that a greater amount of lipase was released when olive oil was present than when glucose was present. Among the various types of triglycerides used as the carbon source, olive oil was found to be most effective in inducing the lipase. Olive oil and mustard oil fatty acids inhibited the lipase more than those of coconut oil. The lipase induced by a particular type of triglyceride did not seem to be specific for the same triglyceride, nor was it inhibited specifically by it. Irrespective of the triglyceride used in the fermentation medium, the lipase produced was most active against coconut oil triglyceride, and this specificity, as shown by lipase activities in an n -heptane system, was not found to be due to a better emulsification of this oil. The lipase of M. hiemalis can be considered to be both constitutive and inducible.