Faecal and urinary losses of nitrogen in cobalt-deficient small East African goats

Abstract

Cohalt deficiency was induced in 3 rumen-fiSlulated small East African goats by feeding them on Chlor is gayana hay (containing 0.02 mg Co/kg dry matter) and a small amount of concentrate supplement for 23 weeks. To 3 contral goats, an oral cobalt chloride drench was administered 3 times a week to provide 0.3 g Co/goat a week. During the 22nd week, faecal and urinary losses of nitrogen were significantly higher (P<0.01) in
cobalt-deficient goats than in cobalt-supplemented goats. The concentration of free ammonia in rumen was higher (1'<0.01) in cobalt-supplemented goats than in cobalt-deficient goats.
A reduction in rumen fermentation of dietary nitrogen,and increased faecal and urinary nitrogen losses probably contribute to slow growth rate and loss of body condition in cobalt-deficient ruminants.