OXALATE ACCUMULATION IN FODDER CROPS AND IMPACT ON GRAZING ANIMALS – A REVIEW
MEENAKSHI GOYAL*
Department of Plant Breeding and Genetics,
Punjab Agricultural University, Ludhiana
*(e-mail : meenakshigoyal@pau.edu)
(Received : 13 November 2018; Accepted : 10 December 2018)
SUMMARY
Oxalate content in some forage crops causes poisoning in ruminants under certain conditions. Many external and internal factors like plant species/variety, plant parts, seasonal variation, nitrogen fertilization and clipping interval etc. have a large effect on oxalate accumulation in forage plants and
thus influence metabolism of grazing animals. In the present paper, an overall view of oxalate accumulation under the influence of these various factors in forage crops has been summarized. Different nitrogen sources vis-à-vis N doses alter the oxalate accumulation to different levels. Nitrate application resulted in higher contents of soluble and total oxalates than ammonium application. With increased harvesting interval, oxalate content showed a decreasing trend in some plants but reverse trend was reported in others. Ruminants tend to be more tolerant of oxalate than non-ruminants. A dose of 0.12 g oxalic acid/kg live weight/d resulted in mild degree of hypocalcaemia in sheep but prolonged grazing on some tropical grasses could result in severe hypocalcaemia in sheep and cattle. However, more research is required for a better understanding of the interactions between oxalate in different
species and grazing animals.
Key words: Clipping interval, Growing environment, Fertilization, Forages, Oxalate