Effects of superphosphate, lime, and stocking rate on pasture and animal production on the Wairarapa Plains

Abstract

The effects of two stocking rates (15 and 22 ewes per ha), two rates of lime (0 and 6300 kg.ha⁻¹), and two rates of superphosphate (125 and 500 kg.ha⁻¹ annually) on incisor teeth wear were measured on the Wairarapa Plains near Masterton. Greater wear of teeth was incurred in ewes stocked at the higher rate, and most wear occurred during winter and spring when soil ingestion was greatest. Levels of vitamin B₁₂, selenium, copper, iron, and zinc in livers were determined on four treatments on completion of the trial. Vitamin B₁₂ levels in the liver were higher on unlimed pastures at the higher stocking rate.

Keywords:

• Superphosphate
• lime
• stocking rate
• tooth wear
• trace elements
• vitamin B₁₂
• selenium
• copper
• iron
• zinc