Từ điển thú y vần O | O Oak Poisoning Both the acorns and the leaves of the oak Quercus spp. may be dangerous when eaten by stock but the leaves are usually harmless unless eaten in large quantities. It is when there is a scarcity of food in pastures towards the end of very dry summers that symptoms of poisoning occur. The animals most affected are young store cattle. In a Northumberland outbreak however in a herd of 40 Galloways 6 cows died and 4 aborted. A taste for oak buds was acquired early in the year when trees were felled and keep was scarce. Felling went on until September when symptoms fever and scouring with blood-stained faeces were first shown after one cow had aborted and died. Horses have been poisoned through eating either oak leaves or acorns. It is well known that both pigs and sheep can eat acorns in small quantities without ill-effects. Signs Ruminants that have eaten many acorns become dull cease feeding lie groaning and appear to be in considerable pain. At first there is severe constipation accompanied by straining and colicky pains cessation of rumination weakness of the pulse and a temperature below normal. Later small amounts of inky-black faeces are passed and a blood-stained diarrhoea sets in. Great prostration is seen and the animals die in from 3 to 7 days when large amounts have been eaten. In chronic cases there is always great loss of flesh and death does not take place till weeks or months after the beginning of the symptoms. Horses may not show signs of pain. The poisoned animal becomes weak and dull has a subnormal temperature may discharge food and saliva from its nostrils show head-pressing have mouth ulcers have reddish-brown urine ataxia and convulsions. Autopsy findings include a uraemic smell from the carcase oedema and haemorrhages and kidney lesions. Treatment Cattle should be given long hay. The animals should be made comfortable with plenty of bedding provided. During convalescence the animals require liberal feeding to make up the loss of .
