Main causes of mortality in growth farms of commercial pullets of the bovans white line

The rearing system of replacement pullets in Mexico is traditionally done on the floor due to its higher performance and resemblance to natural conditions to minimize stress compared to cage rearing.1 However, the type of housing as other management factors (vaccination, weighing, and beak trimming) that is done in the field during the growth phase are important factors to consider in the amount of casualties and that could affect the accumulated mortality during this phase. The health problems of the flock are divided into infectious and non-infectious.2 The causes of mortality due to infectious diseases are only one of a series of factors that can affect the performance of the flock. However, they are controlled based on prevention, strict hygiene programs in incubators, vaccination, the use of food additives and precautions in health.3 Mortality from non-infectious causes is reflected in the main causes of morbidity and mortality that are metabolic disorders or zootechnical management,4 however, the “good” interaction of management, plus health, nutrition and environment not always met, generating malfunctions in the metabolism, physiology and anatomy, all of the above may be associated with poor zootechnical management.5,6 It has an impact on production that is often not quantified in the poultry industry, mainly due to its low percentage and cause, compared with infectious diseases and their economic impact. Hence, the aim was to record the causes of macroscopic mortality in farms with replacement pullets of the Bovans White line from week 1 to 16. The results obtained will help producers to quantify the causes of higher incidence and rethink their strategies production in search of minimizing it.