ASAS Centennial Paper: Developments and future outlook for preharvest food safety

The last century of food animal agriculture is a remarkable triumph of scientific research. Knowledge derived through research has resulted in the development and use of new technologies that have increased the efficiency of food production and created a huge animal production and food manufacturing industry capable of feeding the US population while also providing significant quantities of high-quality food for export to other countries. Although the US food supply is among the safest in the world, the US Center for Disease Prevention and Control estimates that 76 million people get sick, more than 300,000 are hospitalized, and 5,000 die each year from foodborne illness. Consequently, preventing foodborne illness and death remains a major public health concern. Challenges to providing a safe, abundant, and nutritious food supply are complex because all aspects of food production, from farm to fork, must be considered. Given the national and international demand and expectations for food safety as well as the formidable challenges of producing and maintaining a safe food supply, food safety research and educational programs have taken on a new urgency. Remarkable progress has been made during the last century. Wisdom from a century of animal agriculture research now includes the realization that on-farm pathogens are intricately associated with animal health and well-being, the production of high-quality food, and profitability. In this review, some of the developments that have occurred over the last few decades are summarized, including types, sources, and concentrations of disease-causing pathogens encountered in food-producing animal environments and their association with food safety; current and future methods to control or reduce foodborne pathogens on the farm; and present and future preharvest food safety research directions. Future scientific breakthroughs will no doubt have a profound impact on animal agriculture and the production of high-quality food, but we will also be faced with moral, ethical, and societal dilemmas that must be reconciled. A strong, science-based approach that addresses all the complex issues involved in continuing to improve food safety and public health is necessary to prevent foodborne illnesses. Not only must research be conducted to solve complex food safety issues, but results of that research must also be communicated effectively to producers and consumers.     

Massive obstructive urolithiasis in a bull used for artificial insemination

A seven-year-old Jersey bull used for artificial insemination showed clinical signs of obstructive urolithiasis. This was confirmed by catheterisation and subsequent urethrotomy over the site of obstruction distal to the sigmoid flexure. Although urine flow was elicited after removal of the calculi, this was only temporary and the animal had to be killed 24 hours later. On post mortem examination about 2 kg of round, smooth, pearl-like calculi were found in the urinary bladder and the urethra of the sigmoid flexure was studded with similar calculi. It was concluded that urethrotomy at the sigmoid flexure or penectomy post scrotally would not have alleviated this condition.     

Cloning and expression of a cocaine-sensitive dopamine transporter complementary DNA

A rat dopamine (DA) transporter complementary DNA has been isolated with combined complementary DNA homology and expression approaches. The DA transporter is a 619-amino acid protein with 12 hydrophobic putative membrane-spanning domains and homology to the norepinephrine and gamma-aminobutyric acid transporters. The expressed complementary DNA confers transport of [3H]DA in Xenopus oocytes and in COS cells. Binding of the cocaine analog [3H]CFT ([3H]2 beta-carbomethoxy-3 beta-(4-fluorophenyl)tropane) to transfected COS cell membranes yields a pharmacological profile similar to that in striatal membranes.     

The effect of antibody and complement on the expression of herpesvirus of bovine malignant catarrhal fever in cultured rabbit lymphocytes

Using indirect immunofluorescence with a hyperimmune calf serum, a virus-induced antigen was demonstrated on the surface of lymphocytes expressing intracellular malignant catarrhal fever virus antigens. Antibody to the antigen was also detected in terminal sera of both cattle and rabbits. Antisera did not restrict virus expression in explanted lymph nodes unless they were supplemented with two to four units of lytic complement per ml culture. While human, bovine and guinea pig complements caused immune lysis of infected lymphocytes, rabbit complement was ineffective. The relevance of the findings in the pathogenesis of the lymphoid proliferation caused by MCFV is discussed.     

Amylase activity in triticale,X Triticosecale Wittmack

Summary Amylase activity in leaves and the seed exhibited variations among 12 cultivars of hexaploid triticales and was considerably higher than either octaploid triticale or hexaploid wheat. Amylase activity was influenced by the levels of nitrogen and the maturity stages of the kernel. The bran-free endosperm had much lower amylase activity than the whole meal. The measurement of dry matter, starch, total sugars and reducing sugars during the stages of kernal development indicated significant positive correlation between days after anthesis and amounts of starch and dry matter and negative correlation with total sugars, reducing sugars and amylase activity. However, a lower rate of starch accumulation and higher rate of amylase activity prior to kernel maturity was clearly evident.