Factors related to the presentation of ascites and sudden death syndromes in broilers

Abstract

In recent years, mortality and forfeiture due to metabolic disorders have been determinant factors in economic losses to the poultry industry. This article reviews the factors related to the incidence of ascites and sudden death syndromes, as well as the strategies used to control them. While it has been possible to improve the yield of broilers through genetic selection, this has predisposed the birds to suffer from metabolic problems such as ascites and sudden death syndrome, due mainly to the high growth rates obtained. Pulmonary hypertension stands out as the common denominator of all the risk factors that lead to right ventricular hypertrophy, generalized vascular congestion, extravasation of plasma to thoracoabdominal cavity, or ascites. Among the associated factors it is necessary to highlight low temperatures and the altitude above sea level. It has been confirmed that at higher altitude the partial pressure of atmospheric oxygen decreases and under these conditions the pulmonary blood vessels of broilers contract, increasing pulmonary vascular resistance. Among nutritional strategies there are food restriction, supplementation with arginine, omega-3 fatty acids, and alkalinogenic diets, among others. Finally, the economic losses to the poultry industry caused by metabolic disturbances amount to half a billion dollars a year worldwide, due both to forfeiture in slaughter houses and to the mortality rate in farms.