Perirenal Hemorrhage Syndrome of Turkeys: Introduction
(Hypertensive angiopathy, Sudden death syndrome of turkeys) |  |
| Perirenal hemorrhage syndrome (PHS) is a noninfectious cardiovascular disease usually affecting rapidly growing male turkeys 8-15 wk old characterized by sudden death, perirenal hemorrhage, and hypertrophic cardiomyopathy. Mortality is usually 0.5-2% but can be higher; there is no morbidity. Healthy, rapidly growing flocks are more likely to be affected. |
| The pathogenesis is unknown, but PHS is apparently unrelated to pulmonary function or hypertension. Inadequate or inappropriate cardiac response to exercise, resulting in hypotension, vasodilation, arrhythmias, and sudden death, appears most likely. Acute congestive heart failure secondary to cardiac hypertrophy has also been suggested as a potential cause. Renal hemorrhage may occur due to severe passive congestion. |
| Gross lesions include good to excellent body condition, food in crop and stomach, enlarged dark red to purple spleen, variable retroperitoneal hemorrhage around one or both kidneys, generalized congestion, and pulmonary edema occasionally accompanied by hemorrhage. Cardiac hypertrophy involving the left ventricle and intraventricular septum may also be seen. Microscopic changes are consistent with gross findings; proliferative arterial and arteriolar lesions and ruptured renal
veins also are often present. PHS has several characteristics in common with aortic rupture (
Dissecting Aneurysm: Introduction) and flip-over in broilers (
Flip-over Disease: Introduction). |
| Diagnosis is based on history, typical gross lesions, and absence of infectious agents. Extensive PHS lesions may resemble aortic rupture. |
| There is no specific treatment. Factors that decrease growth rate and activity also tend to decrease PHS. Reserpine (0.5 ppm feed) decreases PHS, but aspirin (0.005%) or increased calcium has no effect. Reserpine is not listed in the Feed Additive Compendium as approved for use in feed for turkeys. Increased room temperature and various lighting programs have also reduced PHS. Activities that increase cardiovascular stress (eg, moving birds, tilling litter, noise) should be
minimized, especially between 7 and 15 wk of age. Lower ambient temperatures (55°F [13°C]), intermittent lighting, and leaving toes unclipped increase mortality from PHS. |
| PHS may occur in healthy commercial male turkey flocks regardless of management practices used to prevent its occurrence. |