Antibodies: an alternative for antibiotics?

In 1967, the success of vaccination programs, combined with the seemingly unstoppable triumph of antibiotics, prompted the US Surgeon General to declare that "it was time to close the books on infectious diseases." We now know that the prediction was overly optimistic and that the fight against infectious diseases is here to stay. During the last 20 yr, infectious diseases have indeed made a staggering comeback for a variety of reasons, including resistance against existing antibiotics. As a consequence, several alternatives to antibiotics are currently being considered or reconsidered. Passive immunization (i.e., the administration of more or less pathogen-specific antibodies to the patient) prior to or after exposure to the disease-causing agent is one of those alternative strategies that was almost entirely abandoned with the introduction of chemical antibiotics but that is now gaining interest again. This review will discuss the early successes and limitations of passive immunization, formerly referred to as "serum therapy," the current use of antibody administration for prophylaxis or treatment of infectious diseases in agriculture, and, finally, recent developments in the field of antibody engineering and "molecular farming" of antibodies in various expression systems. Especially the potential of producing therapeutic antibodies in crops that are routine dietary components of farm animals, such as corn and soy beans, seems to hold promise for future application in the fight against infectious diseases.

Economic sustainability of small ruminants production in semi-arid areas of Lebanon.

Small ruminant production in the near east region is facing serious constraint of feed availability. A study was conducted in marginal areas of Lebanon, using a cost-benefit analysis technique (CBA), to assess the feasibility of four small ruminant production systems ranging from semi-nomadic to settled. When the owned labor cost was included as an opportunity cost in the economic analysis, CBA revealed negative returns in all four systems. Only the settled system was profitable according to the financial analysis excluding labor cost. Moreover, feed expenses if coupled with grazing costs represented a major constraint to profitability. To remedy to the feed deficit problem, the potential of using agro-industrial by-products as feed block supplements was investigated. Simulated feed block diets, using the most available by-products, provided a better nutritive value per unit cost than hand-fed diets used in the systems studied. Preliminary analysis showed that the use of feed block diets could improve the economic sustainability of small ruminant production systems.