Brassicaceae

Abstract

DISTRIBUTION: Not usually cultivated as animal feed. Japanese radishes & kale are produced as feed for livestock. When market prices are low or crops are damaged by hail, etc., it is sometimes fed to stock.

BOTANICAL DESCRIPTION: Turnips, radishes, cabbages, cauliflowers, and Brussel sprouts (Brassicaceae) are all vegetables which are produced for human consumption. They do not grow naturally in the wild. The tubers of some are utilised, (turnips, radishes, etc.) , while the leaves and flowers and fruit of others are consumed (cabbages, cauliflowers, etc.). Weeds like wild radish and wild mustard do grow wild.

TOXIC PRINCIPLE: Haemopoietic: • The toxic principle of the Brassicaceae is dimethyl disulphide produced from SMCO. • Dimethyl disulphide reacts with the thiol group of GSH which is then not available to prevent oxidative damage of the red blood cell. • With oxidative damage the haemoglobin is denatured and the protein precipitate as Heinz bodies. • The affected erythrocytes are removed by the RE-system or intravascular haemolysis ensues resulting in haemoglobinaemia and haemoglobinuria. Urogenital: Organic nitriles and glucosinolates are goitrogenic and teratogenic.

SYNDROMES: Heinz body anemia.

SYSTEMS AFFECTED: Haemopoietic and urogenital systems.

CLINICAL SIGNS: Acute: • Haemoglobinuria. Pale, anaemic mucous membranes • Icterus (jaundice) • Diarrhoea • Ruminal stasis Chronic: • Subclinical anaemia. • Ill-thrift. • Poor milk production, poor growth, emaciation. • Infertility.

NECROPSY: Macroscopical findings: Icterus. Anemia – pale mucous membranes, watery blood. Haemoglobinuria and dark pigmented kidneys. Git irritation.

TREATMENT: • Remove feed immediately • Blood transfusion in valuable or stud animals.

PREVENTION: • Brassica’s should be fed only in limited quantities • Feed with other good quality hay, concentrate, etc. • Can slowly increase the percentage of Brassica’s in the ration • Avoid frost damaged plants - may have a higher concentration of the toxic principle.