Neonatal morbidity and mortality of 31 calves derived from somatic cloning.

Abstract

BACKGROUND: The neonatal period is associated with high morbidity and mortality in cloned calves. OBJECTIVE: To describe morbidity and mortality in cloned calves from birth to 2 years of age. ANIMALS: Thirty-one somatic cell-derived Holstein calves delivered at a veterinary teaching hospital. METHODS: Medical files were retrospectively analyzed. RESULTS: Four calves were stillborn. Five calves born alive had physical congenital defects. Twenty-three calves had an enlarged umbilical cord. Laboratory abnormalities included acidemia, respiratory acidosis, hyperlactatemia, anemia, stress leukogram, decreased total protein, albumin and globulins, and increased creatinine. Twenty-five calves survived the 1st hour of life. Among them, 11 stood without assistance within 6 hours of birth, 10 calves took longer than 6 hours to stand, and 4 never stood. Twenty-two calves suffered from anorexia. Twelve calves had complications arising from umbilical cord infections. Three calves developed idiopathic hyperthermia (>40°C). Eight calves suffered from gastrointestinal problems, including ruminal distension, abomasal ulcers, neonatal enteritis, intussusception, and abomasal displacement. Mortality between birth and 3 weeks of age was 32% (10/31). Causes of death and reasons for euthanasia included stillbirths, respiratory failure, and limb deformities. Mortality between 3 weeks and 2 years of age was 19% (4/21), with deaths in this group attributed to generalized peritonitis and complications arising from umbilical infections. Overall, mortality rate within 2 years of age was 14/31 (45%). CONCLUSION AND CLINICAL IMPORTANCE: Respiratory problems, limb deformities, and umbilical infections were the most common causes of morbidity and mortality in these cloned calves.