Introduction:

Diseases in fattening pigs and reproductive sows, in industrial breeding, are similar in all countries and zones due to uniform base provided by genetics, equipments end feed given to them. Several microorganisms join this base and convert to pathogen ones according to anatomy and physiology, the same as the microbiane charge caused by pigs density and the increase of pathogenia of these microorganisms, aggravated with multiple passes between pigs.

The use of additives in feed, vaccine application and shortness of breeding period have reduced mortality produced in the 70s and 80s. That is why, nowadays it has been necessary to find those processes which have a low mortality, but high morbidity, which influence over productivity and economics of pig farms, up to making the farm unviable due to the increase of production costs, joined to the reduction of market prices, as a consequence of world-wide trading.

Essentially we emphasize 5 processes:

1.Initial body weight of the 1 day piglet, and reproductive strategy.

2.Presence of fungus, mycotoxins and Clostridium in feed.

3.Bad quality of fats in feed.

4.Dermatitis-porcine nephropathy and secondary diseases.

5.Nutritional needs of new animal strains