Effects of hypervitaminosis A on liver in newborn lambs by oral supplementation
Subject Areas : clinical veterinary scienceS. Azimpour, 1 , علیرضا Shaghayegh, 2 , , B Gholamhoseini 3
1 - Department of Clinical Science,Veterinary Faculty, Babol Branch, Islamic Azad
2 - Department of Clinical Science, Veterinary Faculty, Karaj branch, Islamic Azad
University, Karaj, Iran.
3 - Department of pathobiology, Veterinary Faculty, Karaj branch, Islamic Azad University,
Karaj, Iran
Keywords: liver, lamb, weight loss, Histopathology, Hypervitaminosis A, oral,
Abstract :
Clinical signs of hypervitaminosis A are associated with the skeletal and skin lesions and adverse effects on the central nervous system. The present study was carried out to determine the effects of oral administration of high dose of vitamin A in newborn lambs. For this purpose 9 mixed male lambs aged 5-days old, with average weight of 4.3 kg were selected. Lambs were divided into two groups of experiment (n=6) and control (n=3). On the frst day of experiment, liver biopsy were taken by a small midline surgery from all lambs. In the following days, experiment group was fed milk containing 30000 Iu/kg of vitamin A daily. This regime was continued until the end of the third month. Blood sampling was taken weekly. The lambs were weighed at the end of the experiment. All lambs were slaughtered at the end of the third month. Liver samples of the slaughtered animals were taken for histopathological investigation and vitamin A analysis. Vitamin A level, ALP and SGOT activities in serum and vitamin A concentration in liver tissue were increased in the experiment group compared to control group (P<0.05). Priportal Hepatitis in light microscopic investigation was seen in experiment group. Weight gain was lower in experimental group compared to control group (P<0.05). The results showed that daily oral administrations of vitamin A approximately 900 times greater than the daily requirement manifests with lower weight gain presumably as a result of hepatic damage.