Cynodon dactylon

Abstract

DISTRIBUTION: It grows in all types of soil, especially sandy soil and fertile soil. It is found in disturbed places such as road reserves, gardens and cultivated lands.

BOTANICAL DESCRIPTION: General: A short, mat-forming perennial grass, which spreads by means of slender stolons and rhizomes. It is a pioneer that will grow on bare soil and begin to rebuild the soil in disturbed places. Leaves: The leaves point upwards. Flowers: The inflorescence consists of 4 - 7 digitately arranged racemes and the spikelets are flat and without awns. September - May.

TOXIC PRINCIPLE: • One possiblity is that ergot-infected seedheads (Claviceps cynodontis) could be responsible for the kweek tremors. • Another possibility is that an endophyte may produce tremorgenic mycotoxins.

SYNDROMES: Kweek tremors, ABPE (Acute Bovine Pulmonary Oedema and Emphysema).

SYSTEMS AFFECTED: Central nervous and respiratory systems.

CLINICAL SIGNS: Kweek tremors have been observed in calves and sheep that have been grazing in pastures of predominantly Cynodon dactylon. Latent period of 1-2 days. Stimulation and exertion (exercise) often precipitate signs. All stages of nervous derangement seen from: • Hypersensitivity • Mild involuntary trembling to spastic tremors of individual muscle groups • Nodding of head, shaking of limbs or trunk • Ataxia, - stiff-legged gait, - side-ways progression, - falling and inability to get up to complete prostration (recumbency) Some cases show hypersensitivity and paddling movements like heartwater. Adopt position of sternal recumbency. • Except for outspoken cases, animals remain alert and retain their appetites. • When withdrawn from infected pastures recover rapidly over a few days. • Usually a non-fatal syndrome.

NECROPSY: • Nothing specific • For ABPE return to ABPE file

TREATMENT: • Symptomatic • Remove from infected pasture and allow recovery.