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Enterotoxaemia is a disease with a high associated mortality rate, affecting beef and veal calves worldwide, caused by C. perfringens alpha toxin and perfringolysin. A longitudinal study was conducted to determine the dynamics of antibodies against these toxins in 528 calves on 4 beef and 15 veal farms. The second study aimed to determine the effect of solid feed intake on the production of antibodies against alpha toxin and perfringolysin. The control group only received milk replacer, whereas in the test group solid feed was provided. Maternal antibodies for alpha toxin were present in 45% of the veal calves and 66% of the beef calves. In beef calves a fluent transition from maternal to active immunity was observed for alpha toxin, whereas almost no veal calves developed active immunity. Perfringolysin antibodies significantly declined both in veal and beef calves. In the second study all calves were seropositive for alpha toxin throughout the experiment and solid feed intake did not alter the dynamics of alpha and perfringolysin antibodies. In conclusion, the present study showed that veal calves on a traditional milk replacer diet had significantly lower alpha toxin antibodies compared to beef calves in the risk period for enterotoxaemia, whereas no differences were noticed for perfringolysin.  相似文献   
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Unhealthy processed food products are increasingly dominating over healthy foods, making food and nutrition environments unhealthier. Development and implementation of strong government healthy food policies is currently being circumvented in many countries by powerful food industry lobbying. In order to increase accountability of both governments and the private sector for their actions, and improve the healthiness of food environments, INFORMAS (the International Network for Food and Obesity/non-communicable diseases (NCDs) Research, Monitoring and Action Support) has recently been founded to systematically and comprehensively monitor food environments and policies in countries of varying size and income. This will enable INFORMAS to rank both governments and private sector companies globally according to their actions on food environments. Identification of those countries which have the healthiest food and nutrition policies and using them as international benchmarks against which national progress towards best practice can be assessed, should support reductions in global obesity and diet-related NCDs.  相似文献   
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