Brisket disease

From Cow
High-altitude grazing associated with brisket disease in cattle
The liver of a calf which died from Brisket disease, with characteristic nutmeg liver (reticulated pattern) due to congestive heart failure[1]

Brisket disease (Altitude sickness; Bovine high-mountain disease; BHMD) is a relatively common hypoxic disease of high-altitude cattle worldwide[2].

This disease is caused by pulmonary arterial hypertension, circulatory edema and congestive heart failure as a result of low-pressures associated with low-oxygen high-altitude grazing (altitude sickness) above 5,000 feet[3].

The hypoxia of high-altitude grazing results in pulmonary hypertension and subsequent right ventricular (RV) hypertrophy[4]. Cardiac failure is an eventual outcome in cattle unadjusted to high altitudes. The disease in cattle is exacerbated by pregnancy, pre-existing pulmonary and cardiovascular diseases as well as consumption of certain weeds such as Oxytropis and Astragalus (locoweeds).

Clinical signs

In some cases, sudden death is the first sign of disease.

General symptoms of altitude sickness in cattle include anorexia, dyspnea, cyanosis, bounding jugular pulse and subacute edema of the brisket, neck and submandibular region[5].

Postmortem examination usually reveals pleural effusion, pulmonary atelectasis, hydropericardium, right ventricular hypertrophy and ascites. The liver becomes swollen with a 'nutmeg' appearance to the cut surface due to vascular fibrosis. The lungs may have varying degrees of atelectasis and interstitial emphysema.

Diagnosis

Diagnosis is based on presenting clinical signs and post-mortem findings.

A differential diagnosis would include traumatic reticulitis[6], parasites and cardiomyopathy.

Treatment

In acutely affected cattle, movement to low-altitude pastures, especially calves and pregnant cows as well as avoiding access to weeds which exacerbate the disease are essential to survival.

Supportive medication such as diuretics may assist recovery. Thoracocentesis will relieve intrathoracic effusion. Relieving cardiac tamponade due to pericardial effusion may be considered by use of pericardiocentesis.

Conditioned cattle, which are more resistant to high-altitude grazing is essential in long-term management of this disease[7].

References

  1. University of Wyoming
  2. Rhodes J (2005) Comparative physiology of hypoxic pulmonary hypertension: historical clues from brisket disease. J Appl Physiol 98(3):1092-1100
  3. Holt TN & Callan RJ (2007) Pulmonary arterial pressure testing for high mountain disease in cattle. Vet Clin North Am Food Anim Pract 23(3):575-596
  4. Malherbe CR et al (2012) Right ventricular hypertrophy with heart failure in Holstein heifers at elevation of 1,600 meters. J Vet Diagn Invest '24(5):867-877
  5. Anand IS & Wu T (2004) Syndromes of subacute mountain sickness. High Alt Med Biol 5(2):156-170
  6. Braun U et al (2007) Clinical findings in 28 cattle with traumatic pericarditis. Vet Rec 161(16):558-563
  7. Williams JL et al (2012) Genotype by environment interaction for growth due to altitude in United States Angus cattle. J Anim Sci 90(7):2152-2158